Production of liquid hydrocarbons from a combination of carbon dioxide and hydrogen or a hydrogen source

Abstract

Disclosed are routes for producing liquid hydrocarbon products containing gasoline and / or diesel boiling range hydrocarbons, and optionally renewable products containing non-petroleum derived carbon. In a typical process, a gaseous feed mixture containing a combination of CO 2 and H 2 and / or CH 4 (or other hydrocarbon sources of H 2 ) is converted by a reforming and / or reverse water gas shift (RWGS) reaction optionally used in combination with Fischer-Tropsch (FT) synthesis and / or cracking. Preferred gaseous feed mixtures are biogas or mixtures of CO 2 and H 2 that are not easily upgraded in conventional processes. The catalysts described herein have high activity to catalyze the reforming (including dry reforming) of CH 4 and other light hydrocarbons (e.g., those produced by FT synthesis and recycled to the process as light fractions) and simultaneously catalyze the RWGS reaction. These attributes provide flexibility with respect to compositions that can be efficiently converted. Optionally, the use of an electrically heated reforming reactor in the first reforming stage or initial reforming stage or RWGS stage can improve the economics of small-scale operation.

Description

Technical Field

[0001] (Cross - reference to Related Applications) This application claims priority to U.S. Provisional Application No. 63 / 344,599, filed May 22, 2022, the entire disclosure of which is incorporated herein by reference.

[0002] (Technical Field) Aspects of the present invention relate to processes and related catalysts for producing liquid hydrocarbons comprising naphtha - boiling - range hydrocarbons, jet - fuel - boiling - range hydrocarbons, and / or diesel - boiling - range hydrocarbons from a gaseous feed mixture comprising carbon dioxide (CO 2 ). In this process, one or more reactions of reforming (including CO 2 and / or steam reforming), reverse water - gas shift (RWGS), and Fischer - Tropsch (FT) synthesis are utilized and optionally used in combination with wax cracking and / or isomerization.

Background Art

[0003] The ongoing search for alternatives to crude oil as a conventional carbon source for hydrocarbon products is driven by various factors. These include the depletion of oil reserves, the expected increase in energy demand, and the growing concern about greenhouse gas (GHG) emissions from non - renewable carbon (here referring to fossil carbon) sources. From the perspective of replacing the carbon content with non - petroleum - derived carbon, the most industrially important and interesting hydrocarbon products include transportation fuels, heating fuels, and precursors for specialty chemicals. Liquid hydrocarbons, i.e., hydrocarbons that are liquid at room temperature, are representative examples of these hydrocarbon products.

[0004] Carbon dioxide (CO 2 ) is a major cause of greenhouse gas emissions and is contained in the gases produced by combustion in engines, power generation, and commercial and residential heating. Generally, in many small - scale and large - scale processes, CO 2In some cases where waste gas containing it is generated, CO 2 can be obtained as a component of a gas mixture containing hydrogen (H 2 ) and / or methane (CH 4 ). In situ, CO 2 may or may not be a combustion product. Examples of such mixtures include industrial exhaust gases obtained by the production of H 4 by the reforming of CH 2 . In this case, CO 2 is used as a reactant (in the case of dry reforming) and / or is produced by the water gas shift reaction. In addition, although the source of natural gas is mainly methane, a significant amount of CO 2 can also be contained. Other gaseous feed mixtures of CO 2 and CH 4 include those in which the latter component is a renewable resource, for example, in certain cases (i) biogas obtained from the anaerobic bacterial digestion of bio-waste or wastewater treatment, (ii) gaseous products of biomass conversion (e.g., gasification, pyrolysis, or hydrothermal decomposition of biomass, such as in the case of supercritical water gasification of biomass), (iii) landfill gas, or (iv) gaseous products of the electrochemical reduction of carbon dioxide, etc.

[0005] Due to its abundant presence in natural gas reserves and oil-related gases, methane has become the focus of various synthetic routes. Currently, natural gas is the least utilized fossil resource. Especially when "burned" natural gas and other resources are too isolated or insufficient in quantity and it is not economical to transport them to large-scale treatment facilities, they are often burned in large quantities. In addition, due to hydraulic fracturing technology, the price of natural gas has decreased in the United States, and the supply of this resource has increased globally. Furthermore, methane is one of the most common products that can be generated from renewable resources, especially bio-waste, biomass, and other resources obtained from the treatment of the above-mentioned resources. Therefore, the conversion of methane, especially non-fossil carbon containing sources such as biogas (e.g., CO 2The conversion of methane derived from (including carbon from biomass) "renewable carbon" is a very interesting area for development on an industrial scale with good economic viability.

[0006] The main commercial processes for converting methane to fuel involve a first conversion step to produce syngas and a subsequent downstream Fischer-Tropsch (FT) conversion step. For the first conversion step upstream of FT, known processes for producing syngas from methane include partial oxidation reforming based on the highly exothermic oxidation of methane with oxygen, and autothermal reforming (ATR) based on a combination of the highly exothermic oxidation of methane with oxygen, steam, the highly endothermic reforming of methane, and the weakly endothermic water-gas shift, which produces a process with a net enthalpy close to zero. On the other hand, in the steam methane reforming (SMR) process, since steam is used as the oxidant, not only is an energy investment required for the production of steam itself, but also the reaction involving methane and water is highly endothermic, so the thermodynamics are very different. The SMR reaction proceeds as follows.

[0007] CH 4 +H 2 O → CO + 3H 2 Recently, the use of carbon dioxide as an oxidant for methane has also been proposed, and the desired syngas is produced by the following reaction of the most oxidized form of carbon and the most reduced form of carbon.

[0008] CH 4 + CO 2 → 2CO + 2H 2

[0009] This reaction is called the "dry reforming" of methane and is very endothermic, so the thermodynamics of the dry reforming of methane are not as favorable as those of ATR or SMR. However, the stoichiometric consumption of 1 mole of carbon dioxide per mole of methane can reduce the overall carbon footprint of liquid fuel production and potentially achieve a more "green" consumption of methane. The CO 2 consumption rate per mole of this feedstock is for higher hydrocarbons (e.g., C 2 ~C6 increases when reforming paraffin), which may be desirable, for example, when the purpose is hydrogen production (e.g., for refinery processes). In any case, the thermodynamic barrier remains a major challenge, related to the fact that CO 2 is completely oxidized and very stable, so a significant amount of energy is required to activate it as an oxidant. Considering this, many catalyst systems have been studied to overcome the activation energy barrier of dry reforming of methane, and these are summarized, for example, in the review by Lavoie (Frontiers in Chemistry (Nov. 2014), Vol. 2 (81): 1-17), and heterogeneous catalyst systems are considered the most popular as a catalytic approach to carry out this reaction.

[0010] Nickel-based catalysts have shown effectiveness in lowering the activation energy of the above dry reforming reaction, but it has also been reported by Lavoie that these catalysts have a high carbon deposition rate (coking). The undesirable conversion of methane to elemental carbon occurs at the reaction temperature usually required for dry reforming of methane, due to methane cracking (CH 4 →C + 2H 2 ) or the Boudouard reaction (2CO → C + CO 2 ). Recently, other types of catalysts, including those containing noble metals on a ceria-containing support, are described in U.S. Patent No. 10,738,247, U.S. Patent No. 10,906,808, U.S. Patent Application Publication No. 2020 / 0087144, and U.S. Patent Application Publication No. 2020 / 0087576, which have been assigned to Gas Technology Institute (Des Plaines, Illinois). Such catalysts have been demonstrated to exhibit high activity and stability (low coking rate) in reforming based on CO 2 alone or a combination of CO 2 and steam. In addition, since these catalysts show high resistance to sulfur-containing contaminants (e.g., H 2 S), the economics of the process can be further improved in terms of usually reducing the cost associated with pre-treatment of the feedstock.

[0011] In the second step involving FT conversion, for syngas containing a mixture of hydrogen and carbon monoxide (CO), successive cleavage of C-O bonds and formation of C-C bonds by incorporation of hydrogen are carried out. By this mechanism, by varying the FT reaction conditions (temperature and feed CO:H 2 ratio) and catalyst characteristics, hydrocarbons with a controllable molecular weight distribution to some extent, particularly linear alkanes, are produced. Such characteristics include pore size and other characteristics of the carrier material. The choice of catalyst can also affect the yield of FT products in other respects. For example, iron-based FT catalysts tend to produce more oxygen compounds, while ruthenium as the active metal tends to produce only paraffins. The reaction pathway of FT synthesis follows a statistical kinetics model, and the carbon number of hydrocarbons follows an Anderson-Schultz-Flory distribution. Hydrocarbons with low and high carbon numbers always constitute part of the FT product slate, but the conversion level can be appropriately adjusted to be favorable for the production of hydrocarbons with the desired molecular weight. Overall, state-of-the-art technology can benefit from processes that efficiently convert industrially available gas mixtures containing other advantageous reactants such as CO 2 and H 2 and / or CH 4 into products containing liquid hydrocarbons characterized as hydrocarbons in, for example, the naphtha boiling range, jet fuel boiling range, or diesel boiling range.

Summary of the Invention

[0012] Aspects of the present invention relate to the discovery of a process that can effectively utilize the carbon content of CO 2 , recognized as an undesirable air pollutant contributing to climate change, in the production of valuable hydrocarbons including liquid hydrocarbons useful as transportation fuels. In this way, CO 2 can advantageously serve to replace hydrocarbon fuels refined from petroleum and other fossil-derived resources. Technologies for concentrating CO 2 from air via a direct air capture route and the like are available, but the present invention is directed to air-extracted CO 2provides a viable option for producing hydrocarbons, which can be implemented on an industrial scale. This is, for example, in contrast to CO that is relatively expensive and limited in volume. 2 In contrast to sequestration.

[0013] In this regard, the present invention relates to C 4 + a novel route for producing hydrocarbons (e.g., hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range, including or consisting of separated and optionally recovered fractions thereof), i.e., a route in which some or all of its carbon content (e.g., at least about 70%), whether expressed on a weight% or mole% basis, is not derived from petroleum, such as when this carbon content is renewable. Advantageously, regardless of whether the carbon content is renewable carbon, at least a portion (e.g., at least about 20%, at least about 30%, or at least about 40%) of the total carbon content of the representative liquid hydrocarbon products described herein (or the C 4 + hydrocarbons contained in these products, or specific boiling range fractions separated from and optionally recovered from these products) is initially present in, for example, a gaseous feed mixture and optionally extracted from air (e.g., by direct air capture) CO 2 can be obtained from. When the renewable carbon content is derived from CO 2 such CO 2 can be obtained, for example, from biogas (i.e., such CO 2 was originally contained in biogas), or from a gas resulting from the decomposition, combustion, or gasification of biomass. For non-renewable carbon content derived from CO 2 such CO 2 can be obtained, for example, as a combustion product of fossil fuels. In any of these cases, and generally, CO 2CO, regardless of whether it is obtained from (i) air, (ii) biomass (e.g., generating biogas), and / or (iii) industrial waste gases such as combustion products, is used to provide at least a portion of the carbon content 2 does not remain or is not emitted into the atmosphere, but C 4 + can be advantageously utilized in the production of hydrocarbons.

[0014] Optionally, renewable CO 2 CO containing 2 in combination with having a carbon content derived from CO to the extent described above, representative liquid hydrocarbon products described herein (C contained in these products 4 + hydrocarbons, and fractions within a specific boiling range separated from these products and optionally recovered) may have a hydrogen content that is at least partially derived from the following. (a) "Electrolytic hydrogen" herein refers to hydrogen produced by electrolysis optionally using renewable electricity such as sunlight, wind power, nuclear power, and hydropower. (b) "Fossil hydrogen by carbon capture and storage (CCS)" herein refers to hydrogen produced by combining coal gasification or natural gas reforming with carbon capture and storage. (c) "Biogasification hydrogen" herein refers to hydrogen produced by biomass gasification. (d) "Methane pyrolysis hydrogen" herein refers to hydrogen produced by methane pyrolysis. For example, processes described herein that utilize electrolytic hydrogen, fossil hydrogen with CCS, biogasification hydrogen, or methane pyrolysis hydrogen in a fresh feedstock containing H 2 can be used to produce these products described herein that contain such C 4 + hydrocarbons and fractions within such a specific boiling range. Thus, at least a portion of the total hydrogen content of these products can be obtained from electrolytic hydrogen, fossil hydrogen by CCS, biogasification hydrogen, or methane pyrolysis hydrogen.

[0015] Accordingly, representative embodiments of the present invention relate to C 4 + hydrocarbon fractions, such as liquid fractions separated and optionally recovered in the processes described herein, 4 + relating to C 4 + hydrocarbon fractions. Such C 4 + hydrocarbon fractions can include hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range. For example, a particular C 4 + hydrocarbon fraction can contain substantially all (e.g., greater than about 95 wt%) of any one of hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, or hydrocarbons in the diesel boiling range, or can be composed of, or essentially composed of, hydrocarbons within such boiling ranges. According to certain embodiments, (i) at least about 20%, at least about 50%, at least about 80%, or at least about 95% of the total carbon content of such liquid hydrocarbon products or C 2 and / or biogas CO 2 and / or CO in the gas resulting from the decomposition, combustion, or gasification of biomass 2 can be obtained from CO in the atmosphere 4 + and / or (ii) at least about 20%, at least about 50%, at least about 80%, or at least about 95% of the total hydrogen content of such liquid hydrocarbon products or C 4 + hydrocarbon products can be from electrolytic hydrogen, fossil hydrogen by CCS, biogasified hydrogen, or methane pyrolysis hydrogen. Importantly, the liquid hydrocarbon products produced by the processes described herein, as well as the C 2 CO in the atmosphere (e.g., obtained from direct air capture) and / or biogas CO 2and / or carbon content that is at least partially, and perhaps substantially completely, derived from CO in the gas resulting from the decomposition, combustion, or gasification of biomass, and / or (ii) hydrogen content that is at least partially, and perhaps substantially completely, derived from electrolytic hydrogen (e.g., obtained from electricity derived from solar and / or wind power), fossil hydrogen by CCS, biogasification hydrogen, or methane pyrolysis hydrogen. Thus, these products and fractions can be related to the processes described herein, in which CO in the atmosphere 2 and / or biogas CO in the gas resulting from the decomposition, combustion, or gasification of biomass, and / or (ii) hydrogen content that is at least partially, and perhaps substantially completely, derived from electrolytic hydrogen (e.g., obtained from electricity derived from solar and / or wind power), fossil hydrogen by CCS, biogasification hydrogen, or methane pyrolysis hydrogen. Thus, these products and fractions can be related to the processes described herein, in which CO in the atmosphere 2 and / or biogas CO in the gas resulting from the decomposition, combustion, or gasification of biomass 2 and / or CO 2 is present as an input to such processes in fresh feed CO 2 and / or CH 4 containing feedstocks (e.g., such feedstocks contain, substantially contain, consist of, or are essentially composed of CO in the atmosphere 2 and / or biogas CO in the gas resulting from the decomposition, combustion, or gasification of biomass 2 and / or CO 2 ), and / or electrolytic hydrogen, fossil hydrogen by CCS, biogasification hydrogen, or methane pyrolysis hydrogen is present as an input to such processes in fresh feed H 2 containing feedstocks (e.g., such feedstocks contain, substantially contain, consist of, or are essentially composed of electrolytic hydrogen, fossil hydrogen with CCS, biogasification hydrogen, or methane pyrolysis hydrogen). Any C 4 + hydrocarbon fraction, particularly any recovered C 4 + hydrocarbon fraction can be an output of such processes.

[0016] A further aspect of the invention is to combine a general CO 2 source, particularly a gas mixture of CO 2 with an H 2 source and / or an H 2 source (i.e., CH 4, C 2 H 6 , C 3 H 8 and / or H 2 O, etc.) in combination, and is related to the discovery that it can be efficiently used as a raw material in the production of liquid hydrocarbon products. Importantly, the entire raw material, and thus all of these components, are C 4 + hydrocarbons for use in one or more reactions of reforming (including CO 2 and / or steam reforming), reverse water gas shift (RWGS), and Fischer-Tropsch (FT) synthesis, and can be used in combination with wax cracking and / or isomerization as required. CH 4 (as a hydrogen source) and CO 2 In the case of a gaseous feed mixture containing both, for example, biogas or a gaseous feed mixture containing biogas, these components react in the reforming stage according to the above dry reforming reaction to produce a synthesis gas intermediate containing H 2 and CO, i.e., an H 2 mixture can be produced. This intermediate can be converted to liquid hydrocarbon products at least in part by FT synthesis and optionally by a combination of FT synthesis and wax cracking. The latter reaction can be used to adjust the carbon number distribution of the hydrocarbons obtained from FT synthesis alone, and in particular, the wax fraction (e.g., usually containing C 20 + hydrocarbons) contained in the FT synthesis effluent (in the absence of cracking) can be converted to normal or branched C 4 ~C 19 hydrocarbons (e.g., the liquid hydrocarbons present in the recovered C 4 + hydrocarbon fraction) that contribute to the yield of liquid hydrocarbons from the process.

[0017] H 2 and CO 2 In the case of a gaseous feed mixture containing both, for example, H produced by steam methane reforming 2Atmospheric CO in gaseous feed mixtures that are or contain industrial off-gases, such as tail gas (or equivalent off-gases) from pressure swing absorption (PSA) units used to purify 2 and / or biogas CO 2 and / or CO 2 In the combination of a gaseous feed mixture that is or contains a mixture of hydrogen from electrolysis, fossil hydrogen with CCS, biogasification, or methane pyrolysis, H 2 and CO 2 may be reacted according to the RWGS reaction to produce a synthesis gas intermediate for conversion to liquid hydrocarbon products, as described above, at least in part via FT synthesis, and optionally via a combination of FT synthesis and wax cracking. As is known in the art, H produced by stream methane reforming may be converted to liquid hydrocarbon products, as described above. 2 The PSA tail gas used to purify H 2 and CH from both steam reforming and RWGS reactions. 4 It is a by-product obtained from the manufacture of H 2 and CO 2 CH 4 If present, CH 4 and CO 2 may react according to the dry reforming reaction described above, thereby producing H in the synthesis gas intermediate. 2 and the CO yield increases, and CO is obtained from the combination of both RWGS and dry reforming.

[0018] Thus, another aspect of the present invention is that the catalysts described herein are 4 and / or C. 2 H 6 , and / or C. 3 H 8 These properties of such catalysts are therefore relevant to the discovery that they have high activity for catalyzing the reforming (including dry reforming) of other hydrogen sources such as sulphur dioxide, and are similarly effective in catalyzing the RWGS reaction under the same conditions. Thus, these properties of such catalysts, as described herein, are particularly useful for the synthesis of CO 2 and H 2and / or H 2 a source (i.e., CH 4 , C 2 H 6 , C 3 H 8 and / or H 2 such as O, a hydrogen source) of a gaseous feed mixture, and all of these components can be advantageously utilized as reactants in these reactions. Such gas mixtures may otherwise be difficult to monetize and can be combusted conventionally to obtain heat. According to some embodiments, for example, those involving the treatment of relatively small-scale gas mixtures, the use of an electrically heated reformer reactor in a first or initial stage (e.g., a reforming stage or an RWGS stage) to carry out one or both of these reactions results in further improved processing efficiency and apparatus compactness and can reduce costs. Small-scale operations can include, for example, the treatment of gaseous feed mixtures obtained from low-volume biogas production facilities or stranded gas reserves. The electrically heated reformer reactor can include one or more resistance heating elements or induction heating elements, which heat the reformer reactor from the inside and / or outside, thereby effectively controlling the local and overall heat input to the reforming / RWGS catalyst bed as described herein. Representative electrically heated reformer reactors provide accurate (e.g., axial and / or radial) and highly responsive bed temperature control, examples of which are described in co-pending U.S. Application No. 17 / 402,865, published as U.S. Application Publication No. 2022 / 0134298, which is hereby incorporated by reference in its entirety.

[0019] Certain embodiments of the present invention relate to a process for producing liquid hydrocarbon products (e.g., hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range), as well as those within the process (e.g., those present in process streams such as the FT synthesis effluent or the polishing effluent described herein) or outside the process (e.g., the recovered C 4 +Relates to a process for producing liquid hydrocarbon products obtained from such processes that include a hydrocarbon fraction). These include liquid hydrocarbon products in which at least a portion (e.g., at least about 70% on a weight or molar basis) of the carbon content of the hydrocarbons contained in these products is renewable carbon. Representative processes are carried out on a gaseous feed mixture in a first stage for performing a reforming and / or RWGS reaction, i.e., a reforming stage, an RWGS stage, or a reforming / RWGS stage. This is followed by a second stage, i.e., a Fischer-Tropsch (FT) synthesis stage, which continues and converts a syngas intermediate produced in the first stage and containing both H 2 and CO (i.e., H 2 / CO mixture). In particular, this intermediate is converted to C 4 + hydrocarbons contained in the liquid hydrocarbon product. The conversion step is carried out at least in part via FT synthesis, and optionally, this step includes a combination of both FT synthesis and wax cracking, and optionally further includes a combination with isomerization. The wax cracking reaction helps to reduce the molecular weight of the hydrocarbons obtained only from FT synthesis (in the absence of wax cracking). Preferably, the combination of the wax cracking and isomerization reactions contributes to dewaxing the FT synthesis effluent and / or the polishing effluent that contains a wax fraction containing normal C 20 + hydrocarbons or contains it otherwise (in the absence of wax cracking and isomerization). That is, wax cracking in combination with FT synthesis, preferably wax cracking and isomerization in combination with FT synthesis, can contribute to effectively reducing or removing the amount of normal C 20 + hydrocarbons contained in the FT synthesis effluent and / or the polishing effluent when a polishing reactor is used in the FT synthesis stage. This, as described above, is the wax fraction (e.g., normal C 20 +(containing hydrocarbons) to the yield of liquid hydrocarbons from the process (e.g., the recovered C described herein 4 ~C 19 in the hydrocarbon fraction) of such hydrocarbons present, either normal or branched C 4 + is achieved by converting to hydrocarbons.

[0020] Wax cracking may be carried out, optionally in combination with isomerization, after FT synthesis, for example in a separate downstream wax cracking reactor, or, when using a mixture of an FT catalyst and a cracking catalyst in the FT reactor, or when using a bifunctional FT / cracking catalyst having both an FT functional component and a cracking functional component, etc., it may be carried out simultaneously with FT synthesis. In either case of an independent wax cracking reactor or an FT reactor in which at least part of the wax cracking is carried out, the effluent obtained from sequential or simultaneous wax cracking in the FT synthesis stage may be referred to as the FT synthesis effluent. According to a more specific embodiment, the FT synthesis stage may include (i) an FT reactor for carrying out wax cracking simultaneously with FT synthesis, optionally in combination with isomerization (e.g., using a catalyst mixture or a bifunctional catalyst), and (ii) a polishing reactor downstream of the FT reactor for carrying out further wax cracking, optionally in combination with further isomerization. The polishing reactor may include one or more polishing catalysts (e.g., at least one such polishing catalyst has the same composition and / or the same form as the cracking catalyst included in the FT reactor, but does not contain an FT catalyst, or otherwise has the same composition as the cracking functional component of the bifunctional catalyst included in the FT reactor, e.g., has the same composition as this bifunctional catalyst but does not contain the FT functional component), as a result, the FT reactor may provide an FT synthesis effluent, and the polishing reactor may provide a polishing effluent.

[0021] According to a specific embodiment, in the first stage, mainly (i) H 2 and CO 2 or (ii) a hydrogen source and CO 2and a catalyst as described herein (e.g., reforming / RWGS catalyst) to produce a synthesis gas intermediate. Other particular embodiments relate to the above process for converting biogas to liquid hydrocarbon products, i.e., the gaseous feed mixture is or includes biogas. Advantageously, biogas is primarily composed of CH 4 and CO 2 Importantly, the C of the liquid hydrocarbon product thus produced is 4 + The carbon content of the hydrocarbons is CH 4 and CO 2 Another particular embodiment relates to the above process, according to which CO, H 2 , CO 2 , and optionally CH 4 Including optional supplementary H 2 The gas obtained from decomposition, combustion, or gasification of biomass incorporating H is converted into liquid hydrocarbon products, i.e., the gaseous feed mixture is optionally mixed with supplemental H 2 Exemplary processes according to these particular embodiments include a process for converting CO into CO during the reforming stage (and possibly the reforming / RWGS stage). 2 and H 2 and / or a hydrogen source, biogas (or a gaseous feed mixture containing biogas), and / or gas obtained from decomposition, combustion, or gasification of biomass (optionally containing CO, H 2 , CO 2 , and optionally CH 4 Additional H including 2 A gas mixture containing a combination of H 2It includes the step of producing a syngas intermediate containing a CO mixture. The process may further include, in the FT synthesis stage, converting the syngas intermediate into liquid hydrocarbon products, at least partially via FT synthesis, optionally via a combination of both FT synthesis and wax cracking, and optionally further in combination with isomerization as described above.

[0022] A further aspect relates to the ability to recycle a portion of the FT synthesis effluent or the polishing effluent obtained from the FT synthesis stage. In the case of the FT synthesis effluent, it does not matter whether this effluent is obtained after optional wax cracking and / or optional isomerization. In particular, the FT synthesis effluent or the polishing effluent, together with the liquid hydrocarbon products, may contain a fraction rich in (i) H 2 and CO 2 or (ii) a hydrogen source and CO 2 . The components (i) or (ii) of this fraction may include unconverted species and / or light hydrocarbon by-products (e.g., CH 4 , C 2 H 6 , C 3 H 8 ) discharged from the FT synthesis stage (e.g., the FT reactor used in this stage or the polishing reactor used in this stage). A representative process may further include separating, from the FT synthesis effluent (regardless of whether it is obtained after optional wax cracking and / or optional isomerization) or the polishing effluent, (A) the liquid hydrocarbon products containing C 4 + hydrocarbons, and (B) a fraction rich in (i) H 2 and CO 2 or (ii) a hydrogen source and CO 2 . The fraction (B) may be recycled to the reforming stage, the RWGS stage, or the reforming / RWGS stage, or to the FT synthesis stage. Otherwise, a portion of the fraction (B) may be recycled to each of these respective stages. It is possible to recycle and operate in this way because the reforming / RWGS catalysts described herein are (i) CO 2 and H 2(Via the RWGS reaction), and also (ii) from CO 2 and a hydrogen source (via the dry reforming reaction), because it is effective for generating H 2 and CO in the syngas intermediate. For example, in the case of a hydrogen source containing one or more of light alkane hydrocarbons (e.g., CH 4 , C 2 H 6 , C 3 H 8 ), the dry reforming reaction can proceed according to the following general reaction.

[0023] C n H 2n+2 +nCO 2 →2nCO+(n + 1)H 2

[0024] The operation of recycling a part of the FT synthesis effluent or the polished effluent obtained by separating the liquid hydrocarbon fraction from such an effluent is such that the reactants (CO 2 included) of the RWGS and dry reforming reactions are recycled until they are all consumed, so there is an advantage that the overall conversion rate of the input carbon containing CO 2 (or the combination of carbon present in CO 2 and carbon from optional hydrocarbons and other carbon sources) approaches 100%, and the input carbon containing CO 2 can be overall highly utilized for the formation of C 4 + hydrocarbons described herein. The recycled fraction, compared to the FT synthesis effluent or the polished effluent, and compared to the syngas intermediate, (i) H 2 and CO 2 based on the total amount in the recycled fraction, or (ii) a hydrogen source and CO 2can be rich in and is usually rich in both (i) and (ii). In this regard, an important advantage associated with the present invention is that the reforming / RWGS catalyst described herein processes the (i) or (ii) of the FT synthesis effluent or the polishing effluent without a "light fraction" fraction and recycles it to the first stage of the process, thereby ultimately converting substantially all or all of the carbon supplied to the process to CO 2、 (e.g., fresh make-up feedstock, or more specifically, fresh make-up CO 2 and / or CH 4 (in the feedstock containing)) to C 4 + is related to the ability to convert to hydrocarbons up to the stoichiometric limit. The composition of the input feedstock can be preferentially controlled to produce a feedstock having a stoichiometry suitable for converting substantially all or all of the carbon supplied to the process containing CO 2 to C 4 + hydrocarbons. This results in an excellent yield of CO 2 carbon-based liquid hydrocarbons compared to a process in which little or no light fraction is recycled. For example, in the case of an operation with recycling, at least about 80%, at least about 90%, or at least about 95% of the CO 2 carbon supplied to the process is converted to liquid hydrocarbon products and / or C 4 + in the separated and optionally recovered C 4 + hydrocarbon fraction. For example, in the case of an operation with recycling, at least about 80%, at least about 90%, or at least about 95% of the input carbon supplied to the process is converted to liquid hydrocarbon products and / or C 4 + in the separated and optionally recovered C 4 + hydrocarbon fraction.

[0025] In yet another representative process that utilizes recycling, the separated C 4 +Recycling all or a portion of the hydrocarbon fraction to the reforming stage or the RWGS stage to produce recovered C output from the process 4 + The control of the hydrocarbon product slate can be improved. For example, one or more separated fractions of the process can include a hydrocarbon fraction in the naphtha boiling range. If all or a portion of such a fraction is recycled to the first stage of a process that reforms hydrocarbons in the naphtha boiling range to supply additional syngas, the product slate or product yield of the process can shift to the recovery of other types of hydrocarbons such as jet fuel boiling range hydrocarbons and / or diesel boiling range hydrocarbons obtained from these hydrocarbon-rich, separated and recovered fractions respectively. Controlling the product slate or product yield in this way is, in addition to CH 4 made possible by the flexibility of the reforming / RWGS catalyst in terms of reforming a wide variety of hydrocarbons.

[0026] Overall, in this specification, CO 2 undesirable CO containing waste gas 2 A process for producing liquid hydrocarbon products from is described. In some cases, when CO 2 is extracted from the air, the CO in the atmosphere 2 is returned to the hydrocarbon, so that the CO emissions from hydrocarbon combustion are effectively reversed. Further environmental benefits are realized in embodiments where H present in the gaseous feed mixture 2 is produced by the electrolysis of water, particularly embodiments produced using electrical power from renewable energy sources such as sunlight, wind energy, CCS-derived fossil hydrogen, biogas hydrogen, or methane pyrolysis hydrogen. As will be understood by those skilled in the art with knowledge of the present disclosure, the processes described herein are expected to replace liquid hydrocarbon products conventionally refined from fossil fuels such as gasoline and diesel fuel with renewable hydrocarbon products made from recycled CO removed from the atmosphere 2 . These processes can similarly, CO 2 2 ​It can convert renewable hydrocarbons (such as those contained in biogas and those generally obtained from biomass (e.g., those obtained from gasification or hydrothermal cracking of biomass)).

[0027] These and other embodiments, aspects, and advantages of the present invention will become apparent from the following detailed description.

Brief Description of the Drawings

[0028] A more complete understanding of the exemplary embodiments of the present invention and their advantages can be obtained by referring to the following description in consideration of the accompanying drawings that provide a flow diagram of a process for producing a liquid hydrocarbon product, with the same reference numbers being used to identify the same or similar features.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0029] In this specification, the expressions "wt%" and "mol%" are used to represent weight percentage and mole percentage, respectively. The expressions "wt ppm" and "mol ppm" represent weight and mole fractions, respectively. In the case of an ideal gas, "mol%" and "mol ppm" correspond to volume percentage and volume parts per million, respectively. In some cases, the percentage "%" may be indicated for the same value whether expressed in weight percentage or mole percentage. For example, (i) the percentage of the raw material carbon content that forms hydrocarbons, or (ii) the carbon content percentage of a liquid hydrocarbon product that is carbon derived from renewable carbon or CO 4 + is the same value whether expressed in weight percentage or mole percentage. 2

[0030] As used herein, the terms "substantially" and "substantial", when referring to a gas, refer to at least about 95 mol%, and when referring to a liquid or solid, refer to at least about 95 wt%. For example, the phrase "substantially all" can be replaced with "at least 95 mol%" or "at least 95 wt%", depending on the situation. When a reference item is "substantially absent" or "substantial absence", this should be understood to mean that the item is present in an amount of up to 5 mol% or up to 5 wt% relative to the total reference. In preferred embodiments, "substantially all" can be replaced with "all", "substantially absent" can be replaced with "absent", and "substantial absence" can be replaced with "absence".

[0031] The term "liquid hydrocarbon product" refers to a product containing hydrocarbons that are liquid at room temperature. Examples of these include hydrocarbons having 4 or more carbon atoms, i.e., the "C 4 + hydrocarbons" referred to herein.

[0032] ​"Hydrogen source" refers to one or more compounds described herein that can produce hydrogen according to various reactions occurring in the reforming stage, RWGS stage, or reforming / RWGS stage. Examples of such compounds include CH 4 、C 2 H 6 、C 3 H 8 、and H 2 O, and the hydrogen source may include one or more of these compounds. According to certain embodiments, the hydrogen source is CH 4 、C 2 H 6 、C 3 H 8 that can produce hydrogen according to the dry reforming reaction described herein. According to certain embodiments, the hydrogen source is CH 4 、C 2 H 6 、C 3 H 8 that can produce hydrogen according to the steam reforming reaction described herein. For example, for any of the embodiments described herein, "hydrogen source" may refer to CH 4 , and the amount (e.g., concentration) of the hydrogen source may refer to methane only. Alternatively, "hydrogen source" may refer to a combination of CH 4 and C 2 H 6 , and the amount (e.g., concentration) of the hydrogen source may refer to the total amount of methane and ethane. Alternatively, "hydrogen source" may refer to a combination of CH 4 、C 2 H 6 、and C 3 H 8 , and the amount (e.g., concentration) of the hydrogen source may refer to the total amount of methane, ethane, and propane. Alternatively, "hydrogen source" may refer to a combination of CH 4 、C 2 H 6 、C 3 H 8 , and 2 , and the amount (e.g., concentration) of the hydrogen source may refer to the total amount of methane, ethane, propane, and water (e.g., in the form of steam).

[0033] The term "hydrocarbons in the naphtha boiling range" is synonymous with "hydrocarbons in the gasoline boiling range" and may be replaced by this term, but C 5 refers to a hydrocarbon fraction containing hydrocarbons having boiling points within the initial ("front end") distillation temperature characteristics of the hydrocarbons, e.g., from about 30 °C (86 °F) to about 40 °C (104 °F), with a representative value of 35 °C (95 °F), and the end point distillation temperature is generally from about 130 °C (266 °F) to about 169 °C (336 °F), typically from about 141 °C (286 °F) to about 163 °C (325 °F), with a representative value of 155 °C (311 °F). The terms "hydrocarbons in the jet fuel boiling range" and "hydrocarbons in the diesel fuel boiling range" refer to a hydrocarbon fraction containing hydrocarbons having boiling points within the front end distillation temperature range of about 135 °C (275 °F) to about 175 °C (347 °F), with a representative value of 155 °C (311 °F). The distillation end point temperature of hydrocarbons in the jet fuel boiling range is generally from about 275 °C (527 °F) to about 300 °C (572 °F), with a representative value of 285 °C (545 °F), while the distillation end point temperature of hydrocarbons in the diesel fuel boiling range is generally from about 300 °C (572 °F) to about 400 °C (752 °F), with a representative value of 370 °C (698 °F). These boiling temperatures are also characteristic of the respective fractions of petroleum-derived gasoline, jet fuel, and diesel fuel boiling ranges and can be measured in accordance with ASTM D86, with the end point being the 95% recovery value. According to some embodiments, for the purpose of characterizing (i) hydrocarbons in the naphtha boiling range, (ii) hydrocarbons in the jet fuel boiling range, and (iii) hydrocarbons in the diesel fuel boiling range, these may each be considered hydrocarbon fractions containing hydrocarbons having normal boiling points between (i) 35 °C (95 °F) and 135 °C (275 °F), (ii) 135 °C (275 °F) and 300 °C (572 °F), and (iii) 300 °C (572 °F) and 400 °C (752 °F). Such fractions can be readily identified, for example, from fractions of the liquid hydrocarbon product obtained from the processes described herein (e.g., after separation from a fraction rich in H 2 / CO 2 -rich fraction or a hydrocarbon / CO 2 -rich fraction).

[0034] In a representative process described herein, the first or initial stage may be referred to as the "reforming / RWGS stage" to indicate that both the reforming reaction and the reverse water gas shift (RWGS) reaction occur to some extent. As understood in the art and in the context of the present disclosure, reforming refers to the reaction of CH 4 and / or optionally other hydrocarbons (e.g., hydrocarbons contributing to the hydrogen source as described above, e.g., C 2 H 6 and / or C 3 H 8 ) with an oxidant, where H 2 and CO (synthesis gas) are produced, and the oxidant preferably contains CO 2 but may optionally contain any one or more of CO 2 , H 2 O, and O 2 . The RWGS reaction is understood in the art as follows.

[0035] H 2 +CO 2 →H 2 O+CO In a broader embodiment, the first or initial stage may be a "reforming stage", in which reforming of CH 4 and / or optionally other hydrocarbons occurs as described above, but the RWGS reaction does not necessarily occur. In other broader embodiments, the first or initial stage may be an "RWGS stage", in which the RWGS reaction occurs as described above, but reforming of CH 4 and / or optionally other hydrocarbons does not necessarily occur. For example, in the case of a gaseous feed mixture containing CH 4 and 2 , the first stage may be a reforming stage in which these components react to produce synthesis gas. However, typically, at least some of the H 2 in the synthesis gas present in the reaction mixture reacts with the CO 2 present in the reaction mixture according to the RWGS reaction, and as a result, the reforming stage may be more specifically characterized as a "reforming / RWGS stage". H 2 and CO 2For a gaseous feed mixture containing, the first stage can be the RWGS stage in which these components react as described above. Thus, CO 2 along with CH 4 (and / or C 2 H 6 and / or C 3 H 8 and other hydrocarbons such as) or H 2 In the case of a gaseous feed mixture containing any of, the first stage or initial stage can be either a reforming stage or an RWGS stage. CH 4 (and / or C 2 H 6 and / or C 3 H 8 and other hydrocarbons such as) and CO 2 (e.g., CH 4 , CO 2 , and H 2 containing) In the case of a gaseous feed mixture, the first stage or initial stage can be a shift / RWGS stage. Gaseous feed mixture

[0036] C 4 + An exemplary process for producing a liquid hydrocarbon product containing hydrocarbons comprises (a) in a reforming stage or an RWGS stage, contacting a gaseous feed mixture with a reforming / RWGS catalyst to produce a syngas intermediate containing an H 2 / CO mixture, and (b) converting the syngas intermediate to a liquid hydrocarbon product, at least in part via Fischer-Tropsch (FT) synthesis. Representative gaseous feed mixtures mainly include (i) H 2 and CO 2 , or (ii) a hydrogen source and CO 2 , and the term "mainly" means that these gaseous feed mixtures have (i) a total amount of H 2 and CO 2 of at least 50 mol%, or (ii) a total amount of a hydrogen source (e.g., which may contain one or more of the above compounds) and CO 2 of at least 50 mol%. In a more specific embodiment, the gaseous feed mixture is (i) H2 and CO 2 are included in a total amount of at least 75 mol%, at least about 90 mol%, or at least about 95 mol%, or (ii) a hydrogen source and CO 2 are included in a total amount of at least 75 mol%, at least about 90 mol%, or at least about 95 mol%. According to other embodiments, a representative gaseous feed mixture may include CH 4 , CO 2 , and H 2 in a total amount of at least 50 mol%, at least about 75 mol%, at least about 90 mol%, or at least about 95 mol%. According to other embodiments, a representative gaseous feed mixture may include CO, CO 2 , and H 2 in a total amount of at least 50 mol%, at least about 75 mol%, at least about 90 mol%, or at least about 95 mol%. Alternatively, in combination with any of the features described herein, a representative gaseous feed mixture may contain little or no other components. For example, in the case of a gaseous feed mixture mainly containing (i) H 2 and CO 2 , such a gaseous feed mixture may contain less than about 25 mol%, less than about 10 mol%, less than about 5 mol%, or less than about 1 mol% of a hydrogen source (e.g., containing CH 4 and optionally combined with other hydrocarbons such as C 2 H 6 and / or C 3 H 8 ). In the case of a gas mixture mainly containing (ii) a hydrogen source (e.g., which may contain one or more of the above compounds) and CO 2 , such a gaseous feed mixture may contain less than about 25 mol%, less than about 10 mol%, less than about 5 mol%, or less than about 1 mol% of H 2 . In the case of a gaseous feed mixture mainly containing (i) H 2、 CO 2 and CO, such a gaseous feed mixture may contain less than about 25 mol%, less than about 10 mol%, less than about 5 mol%, or less than about 1 mol% of a hydrogen source (e.g., containing CH 4 and optionally C 2H 6 and / or C 3 H 8 and may be included in combination with other hydrocarbons such as). The gaseous feed mixture described herein is CO 2 Oxygen-containing components other than, for example, CO, H 2 O, and O 2 One or more of can be included, respectively (individually) or in total amounts, less than about 35 mol%, less than about 15 mol%, less than about 10 mol%, less than about 5 mol%, or less than about 1 mol%. In such cases, since the presence or absence of oxidants other than CO 2 is limited, the reforming of CH 4 generated in the reforming stage or reforming / RWGS stage can be substantially or completely dry reforming and / or may not substantially or completely involve partial oxidation.

[0037] When the gaseous feed mixture mainly contains (ii) a hydrogen source (e.g., CH 4 alone or, optionally, C 2 H 6 and / or C 3 H 8 and combinations with other hydrocarbons such as) and CO 2 are included, step (a) can be, as described above, a reforming stage and, optionally, a reforming / RWGS stage, according to which, in either case, the H 2 / CO in the syngas intermediate mixture, H 2 and CO can be produced from the reaction of CH 4 with CO 2 . When the gaseous feed mixture mainly contains (i) H 2 and CO 2 , step (a) can be, as described above, a RWGS stage and, optionally, a reforming / RWGS stage. When step (a) is a RWGS stage, the H 2 in the syngas intermediate mixture, H 2 / CO can be unreacted in the RWGS reaction of H 2 with CO 2 as described above or can represent an equilibrium amount of H 2 , but this H 2The CO in the / CO mixture can be the CO produced by the RWGS reaction or the unreacted CO. When step (a) is the reforming / RWGS stage, the gaseous raw material mixture mainly containing (i) H 2 and CO 2 further contains CH 4 and optionally C 2 H 6 and / or C 3 H 8 and can be included in combination with other hydrocarbons such as. Therefore, the H 2 in the syngas intermediate / CO mixture, H 2 and CO can be produced from the reaction of CH 4 (optionally C 2 H 6 and / or C 3 H 8 and other hydrocarbons such as) with CO 2 . Further, regardless of whether H 4 (optionally C 2 H 6 and / or C 3 H 8 and other hydrocarbons such as) is produced by reforming, it can also be understood that the H 2 in the syngas intermediate / CO mixture, H 2 and CO can represent the equilibrium amounts in the RWGS reaction. In certain embodiments where the gaseous raw material mixture contains CH 2 (optionally C 4 H 2 and / or C 6 H 3 and other hydrocarbons such as) in combination, the H 8 in the syngas intermediate / CO mixture, H 2 and CO can represent the equilibrium amounts in the combination of the reforming reaction and the RWGS reaction. In the reforming stage or the reforming / RWGS stage, CH 2 (optionally C 4 H 2 and / or C 6 H 3 and other hydrocarbons such as) and CO 8 2 ​As long as it reacts according to the above dry reforming reaction, CH 4 (optionally C 2 H 6 and / or C 3 H 8 in combination with other hydrocarbons such as) reacts with one or both of the other oxidants H 2 O and O 2 to produce H 2 and / or H 2 / CO in the H2 / CO mixture of the syngas intermediate. For example, these other oxidants may also be present in the gas feed mixture, or H 2 O may be present in the reaction mixture as a product of the RWGS reaction (not necessarily present in the gas feed mixture).

[0038] The gaseous feed mixture, or at least the compounds present in this mixture (e.g., CO 2 CH 4 and / or H 2 ) can be obtained from various sources. Advantageously, such sources include waste gases that are considered to have little or no economic value, or gases derived from waste materials that are considered to have little or no economic value, or otherwise CO in the atmosphere 2It can contribute to the level. For example, the gaseous raw material mixture can be or include industrial process waste gas obtained from a steel manufacturing process or a non-ferrous product manufacturing process. Other processes from which all or part of the gaseous raw material mixture is obtained include petroleum refining processes (e.g., processes that generate refinery flue gas), renewable hydrocarbon fuel (biofuel) manufacturing processes (e.g., pyrolysis processes, such as hydrothermal pyrolysis processes, or fatty acid / triglyceride hydroconversion processes), biomass and coal (e.g., lignocellulose and charcoal) gasification processes, power generation processes, carbon black manufacturing processes, ammonia manufacturing processes, other chemical (e.g., methanol) manufacturing processes, and coke manufacturing processes. In some cases, the gaseous raw material mixture can be or include (i) wellhead gas containing methane, or (ii) the gaseous product of the electrochemical reduction of carbon dioxide.

[0039] According to some embodiments, the gaseous raw material mixture contains CO obtained from direct air capture (DAC) 2 (i.e., CO extracted from the atmosphere 2 ). Alternatively, or in combination, the gaseous raw material mixture can contain H obtained from the electrolysis of water by using renewable electricity (e.g., generated from wind or solar energy) 2 . For example, the gaseous raw material mixture contains CO 2 and H 2 (e.g., in the combined amounts as described above), all or substantially all of the CO 2 is obtained from direct air capture, and / or all or substantially all of the H 2 is electrolytic hydrogen (i.e., hydrogen obtained from the electrolysis of water). Alternatively, such hydrogen can be fossil hydrogen, biogas hydrogen, or methane pyrolysis hydrogen by carbon capture and storage (CCS).

[0040] A particularly interesting gaseous feed mixture is biogas, which is understood to include the anaerobic bacterial digestion products of biowaste and landfill gas. Typically, biogas contains methane in an amount of about 35 mol% to about 90 mol% (e.g., about 40 mol% to about 80 mol% or about 50 mol% to about 75 mol%), and CO in an amount of about 10 mol% to about 60 mol% (e.g., about 15 mol% to about 55 mol% or about 25 mol% to about 50 mol%). 2 including. 2 N 2 H 2 H 2 Each gas of S and O may be present in trace amounts (e.g., the total amount is less than 20 mol%, or less than 10 mol%). Thus, in some embodiments, the gaseous feed mixture may be biogas or include biogas.

[0041] Another gaseous feed mixture of interest is natural gas containing methane in an amount of about 65 mol% to about 98 mol% (e.g., about 70 mol% to about 95 mol%, or about 75 mol% to about 90 mol%) and CO in an amount of about 3 mol% to about 35 mol% (e.g., about 5 mol% to about 30 mol%, or about 10 mol% to about 25 mol%). Other hydrocarbons (e.g., ethane, propane) and nitrogen may also be present in trace amounts. Of particular interest is residual natural gas that is difficult to convert to syngas intermediates in an economical process using known processes. Thus, in some embodiments, the gaseous feed mixture may be natural gas containing CO in a relatively high amount, such as at least about 10 mol% or at least about 25 mol%, or may include natural gas. 2 and. 2 including.

[0042] A further interesting gaseous feed mixture is, for example, a PSA tail gas with reduced hydrogen obtained from a hydrogen production process including steam methane reforming (SMR) as described above. This mixture contains (i) methane in an amount of about 5 mol% to about 45 mol% (e.g., about 10 mol% to about 35 mol% or about 15 mol% to about 25 mol%), (ii) CO in an amount of about 20 mol% to about 75 mol% (e.g., about 25 mol% to about 70 mol% or about 35 mol% to about 60 mol%). 2and (iii) H 2 contains H2 in an amount of from about 10 mol% to about 45 mol% (e.g., from about 15 mol% to about 40 mol% or from about 20 mol% to about 35 mol%). The remainder of this stream may mainly contain water vapor and / or CO. Thus, in some embodiments, the gaseous feed mixture can be or can contain a PSA tail gas with reduced hydrogen.

[0043] Of further interest are gaseous feed mixtures that are gas effluents from biological (bacterial) fermentations integrated with a hydrogen production process. Such integrated fermentation processes are described, for example, in U.S. Application No. 9,605,286, U.S. Application No. 9,145,300, U.S. Application No. 2013 / 0210096, and U.S. Application No. 2014 / 0028598. Such gaseous effluents contain (i) methane in an amount of from about 5 mol% to about 55 mol% (e.g., from about 5 mol% to about 45 mol% or from about 10 mol% to about 40 mol%), (ii) CO in an amount of from about 5 mol% to about 75 mol% (e.g., from about 5 mol% to about 60 mol% or from about 10 mol% to about 50 mol%) 2 and (iii) H in an amount of from about 5 mol% to about 40 mol% (e.g., from about 5 mol% to about 30 mol% or from about 10 mol% to about 25 mol%). 2 The remainder of this stream may mainly contain water vapor and / or CO. Thus, in some embodiments, the gaseous feed mixture can be or can contain such a gaseous effluent from fermentation.

[0044] Of further interest are gaseous feed mixtures that are gas effluents from biomass gasification, with additional H 2 being supplemented as needed. Such gaseous effluents contain (i) methane in an amount of from about 0 mol% to about 15 mol% (e.g., from about 0 mol% to about 10 mol% or from about 0 mol% to about 5 mol%), (ii) CO in an amount of from about 0 mol% to about 60 mol% (e.g., from about 5 mol% to about 50 mol% or from about 15 mol% to about 45 mol%) 2 and (iii) H in an amount of from about 5 mol% to about 40 mol% (e.g., in an amount of from about 5 mol% to about 30 mol%, about 10 mol%, or from about 10 mol% to about 25 mol) 2may include. The remainder of this stream may mainly consist of water vapor and / or CO. Thus, in some embodiments, the gaseous feed mixture can be or can include a gaseous effluent from biomass gasification, and additional H 2 can be supplemented as needed.

[0045] In some embodiments, the composition of the gaseous feed mixture described herein can represent the combined composition of two or more streams that are separately fed to a reactor used in the reforming or RWGS stage. The separate streams can include, for example, a recycle stream or one type of stream, or one type of stream (e.g., CH 4 -rich stream) with respect to the gaseous feed mixture. In certain embodiments where recycling is utilized, the gaseous feed mixture can be provided to such a reactor or reaction stage as a combination of (A) fresh make-up feedstock and (B) (i) H 2 and CO 2 or (ii) a hydrogen source and a CO 2 -rich fraction. That is, the gaseous feed mixture can include (A) and (B), and as a result, according to certain embodiments related to the "gaseous feed mixture" described herein, the fresh make-up feedstock can be part of such a gaseous feed mixture. Thus, the components of the gaseous feed mixture can include (A) fresh gaseous feed mixture components that function as inputs to the overall process and (B) recycled gaseous feed mixture components. Specific examples of (A) include fresh make-up CO 2 and / or CH 4 -containing feedstocks, and fresh make-up H 2 -containing feedstocks. The former includes CO 2 obtained from DAC, exhaust associated with the combustion of biomass or the gasification of biomass, and the latter includes H 2 such as electrolytic hydrogen, fossil hydrogen by carbon capture and sequestration (CCS), biogasification hydrogen, or methane pyrolysis hydrogen. Exemplary fresh make-up CO 2 and / or CH 4The feedstock contains sustainable carbon from biogenic sources etc., and thus (a) CO obtained from DAC 2 , (b) CO obtained from biogas 2 and / or CH 4 , and / or (c) CO obtained from biomass gasification 2 , CO, and / or CH 4 may be included. Specific examples of (B) include (i) H 2 and CO 2 or (ii) a fraction rich in a hydrogen source and CO 2 , and recycling of at least a portion of a hydrocarbon recycle, i.e., a fraction rich in naphtha boiling range hydrocarbons, etc., of C 4 + is included.

[0046] The components (A) and (B) of the gas mixture may be combined upstream of the reactor used in the reforming or RWGS stage or, otherwise, added directly to this reactor in separate streams, provided that the "gaseous feedstock mixture" may, in certain embodiments, refer to a composition formed within this reactor (e.g., in situ, at the reactor inlet, etc.) or a composition represented by combining at least components (A) and (B). Considering the various fresh and recycle components of the gaseous feedstock mixture and the various possible combinations of such components, generally, the gaseous feedstock mixture supplied to the reactor used in the reforming or RWGS stage contains CO 2 , CO, H 2 , and light fractions (e.g., CH 4 , and optionally C 2 H 6 and other light hydrocarbons such as C 3 H 8 ), with auxiliary H 2 O (steam) added as needed to facilitate SMR and adjust the H 2 :CO molar ratio of the syngas intermediate. (A) Fresh gaseous feedstock mixture components are CO 2 and H 2in combination with light hydrocarbons (e.g., mainly CH 4 ), and, for the RWGS reaction and / or the (B) recycled gaseous feed mixture component, as long as H 2 O (steam) may also be present in the gaseous feed mixture, the reforming / RWGS reactor used in the first stage of the process may be considered a "tri-converting" reactor as long as it is used to carry out (i) dry reforming, (ii) steam reforming, and (iii) the RWGS reaction to produce a syngas intermediate containing an H 2 / CO mixture.

[0047] (i) The fraction rich in H 2 and CO 2 , or (ii) the fraction rich in a hydrogen source and CO 2 , according to alternative embodiments, in accordance with the further disclosure below, including reference to FIGS. 1 and 2, more specifically, may refer to "a part" of such a fraction (i) or (ii), e.g., the recycled portion of this fraction, or a part of such a recycled portion. For example, a purge stream, a sampling stream, etc. are removed from the fraction of the FT synthesis effluent rich in (i) H 2 and CO 2 , or (ii) a hydrogen source and CO 2 , and only the recycled portion of such a fraction (i) or (ii) is returned to the process, e.g., the first stage (e.g., the reforming stage, e.g., the reforming / RWGS stage, or the RWGS stage) and / or the FT synthesis stage, and optionally, different parts of such a recycled portion of the fraction (i) or (ii) are routed to different stages. Similarly, any description of hydrocarbon recycling, such as the recycling of a separated fraction rich in C 4 + hydrocarbons, may more specifically refer to a part of such a fraction. Considering the above description and the further description of the recycling operation herein, the gaseous feed mixture may contain fresh make-up feed and, optionally, (i) the fraction rich in H 2 and CO 2 separated from the FT synthesis effluent, or (ii) a hydrogen source and CO 2It may be included in combination with the recycled portion of the fraction rich in (or a part of such fraction (i) or (ii)) and / or optionally in combination with hydrocarbon recycle.

[0048] According to the above description, in some embodiments, the composition of the gaseous feed mixture described herein may represent the combined composition of two or more streams that are separately fed or input into the reactor used in the reforming stage or the RWGS stage. The separate streams can be, for example, a fresh feed stream and / or a recycle stream (e.g., a fresh make-up feed stream and / or (A) fraction (i) or (ii) described herein, or the recycled portion of such fraction and / or (B) hydrocarbon recycle), or a stream of one component, or a stream rich in one component with respect to the gaseous feed mixture (e.g., a stream rich in CH 4 A stream rich in). Any of the compositional features described above with respect to the gaseous feed mixture can, according to an alternative embodiment, be applied to a fresh make-up feed that is part of the gaseous feed mixture fed or input into the reactor used in the reforming stage or the RWGS stage, such as in the case of a recycle operation. Reforming / RWGS catalyst

[0049] As described above, an important aspect related to the present invention is that the catalyst described herein is a hydrocarbon (e.g., CH 4 , C 2 H 6 , and / or C 3 H 8) reforming (including dry reforming) and the RWGS reaction can be catalyzed to varying degrees depending on the composition of the specific gaseous feed mixture and the specific reforming / RWGS conditions used as described above. This provides a significant degree of flexibility with respect to the composition of the gaseous feed mixture that can be processed into synthesis gas intermediates using reforming reactions or RWGS reactions. As used herein, the term "reforming / RWGS catalyst" refers to a catalyst having at least some activity for catalyzing reforming (regardless of whether such a stage can be characterized as a reforming stage or an RWGS stage) and / or at least some activity for catalyzing RWGS at an initial stage of the process. In preferred embodiments, such a catalyst catalyzes both reactions to at least some extent at the reforming / RWGS stage, taking into account the gaseous feed mixture and conditions used.

[0050] Representative embodiments include contacting the gaseous feed mixture described herein with a reforming / RWGS catalyst in a reforming stage or an RWGS stage. This contacting can be carried out batchwise, but is preferably carried out continuously, by a continuous flow of the gaseous feed mixture into one or more reactors (preferably a single reactor) containing the reforming / RWGS catalyst used at this stage (e.g., such that the catalyst is disposed within the catalyst bed volume in the reactor). Thus, the reforming stage or the RWGS stage can similarly include continuously removing from the reactor(s) a synthesis gas intermediate containing an H 2 / CO mixture, i.e., the intermediate product can contain both H 2 and CO, and such H 2 and CO can be unreacted gas (present in the gaseous feed mixture) or can be produced from the reforming and / or RWGS reactions described above.

[0051] The catalysts described herein, compared to conventional reforming catalysts, in particular, C 2 + olefinic hydrocarbons and / or H 2Exhibits several important advantages in terms of resistance to specific components that may be present in the gaseous feed mixture, such as S or other sulfur-containing components (e.g., mercaptans). Such properties reduce important pretreatment requirements of conventional processes, thereby improving flexibility in economically producing synthesis gas intermediates from common process streams containing such components at high concentrations, even at relatively small operating scales. In some embodiments, any of the gaseous feed mixtures described herein contain CO 2 , CH 4 , and / or H 2 , and in addition, one or more C 2 + olefinic hydrocarbons such as ethylene, propylene, butene, pentene, and / or C 6 + olefinic hydrocarbons. In one embodiment, the gaseous feed mixture may contain one or more C 2 + olefinic hydrocarbons selected from the group consisting of ethylene, propylene, butene, pentene, and combinations thereof. Any one or combination of these olefinic hydrocarbons may be present, for example, in an amount of at least about 0.3 mol% (e.g., about 0.3 mol% to about 15 mol%), for example at least about 1 mol% (e.g., about 1 mol% to about 10 mol%), or in a total (combined) amount. Generally, one or more hydrocarbons other than CH 4 may be present in the gaseous feed mixture in an amount of at least about 3 mol% (e.g., about 3 mol% to about 45 mol%), for example at least about 5 mol% (e.g., about 5 mol% to about 30 mol%), or in a total (combined) amount. In terms of sulfur resistance, the reforming / RWGS catalysts described herein provide additional advantages related to the ability to process sulfur-containing gaseous feed mixtures, such as those containing natural gas that may contain sulfur in the form of H 2 S or other sulfur-containing components, or those derived from natural gas. Generally, the gaseous feed mixture contains at least about 1 mol ppm (e.g., about 1 mol ppm to about 1 mol%) of total sulfur (e.g., H 2present as S and / or other sulfur-containing components), for example, containing at least about 3 molar ppm (e.g., from about 3 molar ppm to about 5000 molar ppm) of total sulfur, at least about 10 molar ppm (e.g., from about 10 molar ppm to about 1000 molar ppm) of total sulfur, or at least about 100 molar ppm (e.g., from about 100 molar ppm to about 1000 molar ppm) of total sulfur.

[0052] Improvement in the stability of the reforming / RWGS catalysts described herein, particularly non-CH that generally promotes catalyst deactivation as described herein 4 The improvement in stability with respect to a gaseous feed mixture containing hydrocarbons and / or sulfur-containing components can be due, at least in part, to its high activity that appears at a lower operating temperature (reactor or catalyst bed). Thereby, the rate of coke formation and deposition on the catalyst surface is reduced, and stable operation is extended. The reforming / RWGS catalysts described herein can achieve a predetermined or target level of performance (e.g., with respect to CH 4 conversion) at a relatively low operating temperature (or average catalyst bed temperature) as reforming / RWGS conditions. Thus, such catalysts are also called "cool" reforming catalysts, and the related process can also be called a "cool" reforming process.

[0053] Typical reforming / RWGS catalysts suitable for catalyzing the reforming and / or RWGS reactions described herein contain a noble metal, and in some cases, two or more noble metals on a solid support. The solid support contains cerium oxide, or more specifically, cerium oxide combined with a suitable amount (e.g., from about 5 wt% to about 35 wt%) of a suitable binder (e.g., alumina) to impart mechanical strength.

[0054] The term "on a solid support" is intended to encompass catalysts in which the active metal(s) is / are on the surface of the support and / or within the porous internal structure of the support. The solid support preferably contains a metal oxide, and in particular cerium oxide is of interest. Cerium oxide can be present in an amount of at least about 60 wt%, preferably at least about 75 wt% (e.g., relative to the total amount of metal oxide(s) in the solid support), based on the weight of the solid support. Whether in oxide form or not, cerium can be present in an amount of about 30 wt% to about 80 wt%, preferably about 40 wt% to about 65 wt% of the catalyst. The solid support can contain all or substantially all (e.g., more than about 95 wt%) of the cerium oxide, or all or substantially all (e.g., more than about 95 wt%) of the total amount of cerium oxide and a second metal oxide (e.g., aluminum oxide) that functions as a binder. According to certain embodiments, the reforming / RWGS catalyst contains a noble metal such as Pt on a solid support containing cerium oxide in the above amounts (e.g., at least about 60 wt%), and aluminum oxide occupies all or substantially all of the remainder of the solid support (e.g., cerium oxide and aluminum oxide are present in a total amount of at least about 95 wt% of the solid support), and this amount of aluminum oxide can correspond to all or substantially all of the remainder of the reforming / RWGS catalyst, excluding the metal (e.g., Pt) deposited on the solid support. Representative solid supports can contain at least about 70 wt%, or at least about 75 wt% of cerium oxide, and at least about 10 wt%, or at least about 15 wt% of aluminum oxide, and the latter component of the solid support is a relatively non-acidic metal oxide that adds mechanical strength.

[0055] The solid support may contain one or more metal oxides other than cerium oxide, such as aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, iron oxide, vanadium oxide, chromium oxide, nickel oxide, tungsten oxide, strontium oxide, etc., in individual amounts independently, or, when there are two or more such other metal oxides, in combined amounts, and the amount corresponds to a small amount such as less than about 50 wt%, less than about 30 wt%, less than about 10 wt%, or less than about 5 wt% of the solid support. Preferably, the solid support substantially does not contain one or more of silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, iron oxide, vanadium oxide, chromium oxide, nickel oxide, tungsten oxide, and strontium oxide. For example, these metal oxides may be present in individual amounts independently in an amount less than about 3 wt%, less than about 0.5 wt%, or less than about 0.1 wt% of the solid support, or in combined amounts in the case of two or more such other metal oxides. For illustrative purposes, in certain embodiments, (i) silicon oxide (silica) may be present in an amount less than about 0.5 wt% of the solid support, (ii) nickel oxide may be present in an amount less than about 0.5 wt% of the solid support, or (iii) silicon oxide and nickel oxide may be present in a total amount less than about 0.5 wt% of the solid support. In other embodiments, the solid support contains one or more of other metal oxides including aluminum oxide in individual amounts independently, or in combined amounts when there are two or more of such other metal oxides, and occupies a major portion such as more than about 50 wt%, more than about 70 wt%, or more than about 90 wt% of the solid support. In such cases, the solid support may optionally contain cerium oxide in an amount representing a small amount such as less than about 50 wt%, less than about 30 wt%, or less than about 10 wt% of the solid support. Such a small amount of cerium oxide can also represent all or substantially all of the remainder not represented by one or more of such other metal oxides of the solid support.

[0056] According to certain embodiments, the solid support may include, in addition to cerium oxide, a second metal oxide that functions as a binder for the cerium oxide. Such a second metal oxide may be selected from the group of the other metal oxides described above, namely, aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, iron oxide, vanadium oxide, chromium oxide, nickel oxide, tungsten oxide, and strontium oxide. Such a second metal oxide may be present in the solid support in an amount generally from about 1 wt% to about 45 wt%, typically from about 5 wt% to about 35 wt%, and often from about 10 wt% to about 25 wt%. Preferably, the solid support comprises cerium oxide and the second metal oxide in a total amount generally of at least about 85 wt%, typically at least about 95 wt%, and often at least about 99 wt% of the solid support. The solid support may comprise cerium oxide and the second metal oxide in a total amount generally of at least about 85 wt%, typically at least about 92 wt%, and often at least about 95 wt% of the reforming / RWGS catalyst. A preferred second metal oxide that acts as a binder for cerium oxide is aluminum oxide.

[0057] A preferred property of the solid support (e.g., mainly comprising cerium oxide) and the resulting reforming / RWGS catalyst is low acidity. In this regard, excessive acidic sites, particularly strong Bronsted acid sites, on the support or catalyst are thought to contribute to coking and catalyst deactivation during reforming and / or the RWGS reaction. Importantly, despite the fact that strong acid sites are known to promote the activity of many important commercial reactions, the advantage of a low proportion or concentration of Bronsted acid sites is obtained in establishing a commercially viable catalyst life. A method widely used for the determination and quantification of the acid point strength of solid materials is temperature-programmed desorption of ammonia (NH 3 -TPD) using ammonia as a molecular probe. According to this method, a sample of the solid material is prepared by degassing and activating it at high temperature and in an inert environment to remove water and other bound species. Next, the sample is exposed to NH 3is saturated and subsequently purged with an inert gas (e.g., helium) to remove physically adsorbed NH 3 conditions are provided. Temperature-programmed desorption of the activated and saturated sample is initiated by raising the temperature at a predetermined rate (e.g., 10 °C / min) to a final temperature (e.g., 400 °C) under a stream of inert gas. The NH 3 concentration in this gas is continuously measured as it is discharged from acidic sites of the solid material where the intensity increases with the increase in desorption temperature. Measurement of the NH 3 concentration in the flowing inert gas can be performed, for example, using gas chromatography with a thermal conductivity detector (GC-TCD).

[0058] Typically, the NH 3 concentration vs. temperature profile contains peaks at low and high temperatures corresponding to sites of the solid material with relatively low and high acid strengths, respectively. The area under these peaks can provide the relative concentration of acid sites of different types of acid strengths (e.g., expressed as a percentage of total acid sites), or these areas can be used to determine the absolute concentration of different types (e.g., expressed in milliequivalents per gram of solid material). For a solid support or a reformed / RWGS catalyst that generates two peaks in the NH 3 concentration vs. temperature profile over a relevant range, e.g., 100 °C to 400 °C, the first low-temperature peak may be associated with weak Lewis acid sites and the second high-temperature peak may be associated with strong Brønsted acid sites. Considering that for typical solid supports (e.g., mainly containing cerium oxide) and reformed / RWGS catalysts having such supports (where the influence on the NH 3 -TPD analysis of the catalyst-active metal deposited on such a support is relatively small or negligible), the NH 3 obtained from the NH 3The concentration vs. temperature profile (such a profile has, for example, two distinguishable peaks) shows a maximum NH concentration at temperatures below about 300 °C (e.g., from about 150 °C to about 300 °C), more typically below about 250 °C (e.g., from about 150 °C to about 250 °C). 3 Thus, this maximum NH concentration may be associated with a low temperature peak corresponding to weak Lewis acid sites, and the maximum NH concentration and the temperature at which this concentration is shown define a point on this low temperature peak. Comparing the peak area of this low temperature peak to the peak area of a high temperature peak corresponding to strong Brønsted acid sites, the Lewis acid sites can account for at least about 25%, at least about 30%, or at least about 35% of the total acid sites (e.g., the total acid sites including both Lewis acid sites and Brønsted acid sites). The high temperature peak may show a maximum NH concentration at a temperature of, for example, from about 300 °C to about 350 °C, or more typically from about 300 °C to about 325 °C. 3 The maximum NH concentration associated with the low temperature peak is usually higher than the maximum NH concentration associated with the high temperature peak, further indicating that the weak Lewis acid sites contribute a significant proportion of the overall acid sites of the solid support or the modified / RWGS catalyst. In a representative embodiment, the solid support or the modified / RWGS catalyst can have a Lewis acid site concentration of at least about 0.25 milliequivalents per gram (meq / g) (e.g., from about 0.25 meq / g to about 1.5 meq / g), more typically at least about 0.35 meq / g (e.g., from about 0.35 meq / g to about 0.85 meq / g). 3 Solid supports (e.g., mainly containing cerium oxide), and modified / RWGS catalysts containing such supports, have a surface area of from about 1 m² / g to about 100 m² / g, such as from about 10 m² / g to about 50 m² / g. 3 The maximum NH concentration associated with the low temperature peak 3 is usually higher than the maximum NH concentration associated with the high temperature peak 3 which further indicates that the weak Lewis acid sites contribute a significant proportion of the overall acid sites of the solid support or the modified / RWGS catalyst. In a representative embodiment, the solid support or the modified / RWGS catalyst can have a Lewis acid site concentration of at least about 0.25 milliequivalents per gram (meq / g) (e.g., from about 0.25 meq / g to about 1.5 meq / g), more typically at least about 0.35 meq / g (e.g., from about 0.35 meq / g to about 0.85 meq / g).

[0059] Solid supports (e.g., mainly containing cerium oxide), and modified / RWGS catalysts containing such supports, have a surface area of from about 1 m² / g to about 100 m² / g, such as from about 10 m² / g to about 50 m² / g. 2 / g to about 100 m² / g, such as about 10 m² / g to about 50 m² / g 2 / g, for example about 10 2 / g to about 50 m² / g 2It may have a surface area of / g. The surface area can be measured according to the BET (Brunauer, Emmett, and Teller) method based on nitrogen adsorption (ASTM D1993-03(2008)). The carrier and / or catalyst may have a total pore volume of pores in the size range of 1.7 to 300 nanometers (nm) of about 0.01 cc / g to about 0.5 cc / g, for example about 0.08 cc / g to about 0.25 cc / g. The pore volume can be measured by mercury porosimetry. The average pore diameter of the carrier and / or catalyst may be about 2 to about 75 nm, for example about 5 to about 50 nm. The carrier and / or catalyst may be such that (i) about 10% to about 80% of its pore volume, for example about 30% to about 55%, is due to macropores with a size exceeding 50 nm, (ii) about 20% to about 85% of its pore volume, for example about 35% to about 60%, is due to mesopores with a size of 2 to 50 nm, and / or (iii) less than about 2% of its pore volume, for example less than about 0.5%, is due to micropores with a size less than 2 nm. The pore size distribution can be obtained using the Barrett, Joyner, and Halenda method.

[0060] Noble metals are understood to refer to a class of metal elements that are resistant to oxidation. In representative embodiments, the noble metal, and in some cases at least two noble metals, of the reforming / RWGS catalyst can be selected from the group consisting of platinum (Pt), rhodium (Rh), ruthenium (Ru), palladium (Pd), silver (Ag), osmium (Os), iridium (Ir), and gold (Au). The term "consisting of" is used only to indicate members of the group from which the noble metal(s) are selected according to a particular embodiment and does not exclude the addition of other noble metals and / or other metals in general. Thus, catalysts containing noble metals include catalysts containing at least two noble metals, catalysts containing at least three noble metals, as well as catalysts containing two noble metals and a third non-noble metal such as a promoter metal (e.g., a transition metal). According to a preferred embodiment, the noble metal is present in an amount of about 0.05 wt% to about 5 wt%, about 0.1 wt% to about 3 wt%, about 0.3 wt% to about 1 wt%, or about 0.5 wt% to about 2 wt% based on the weight of the catalyst, or at least two noble metals are present independently. For example, a representative reforming / RWGS catalyst can contain the noble metal Pt, the noble metal Rh, or a combination of the two noble metals Pt and Rh, and such noble metal(s) can be present independently in an amount within any of these ranges (e.g., about 0.05 wt% to about 5 wt%), or otherwise in a combined amount within any of these ranges. That is, either Pt is present in such an amount, Rh is present in such an amount, or both Pt and Rh are present in such an amount. Preferred noble metal-containing reforming / RWGS catalysts contain one or both of Pt and Rh, and either of them can be present in an amount of about 0.3 wt% to about 1 wt% whether used alone or in combination, and as described above, are present on a support that contains substantially all, or consists essentially of, cerium oxide and optionally a metal oxide binder (e.g., aluminum oxide). Pt is particularly preferred as the noble metal. Regardless of the noble metal(s) used and their amounts used, these noble metals are preferably in the form of the element (metal or zero oxidation state).For example, with respect to the above-preferred noble metal-containing reforming / RWGS catalyst, such a catalyst may contain one or both of Pt and Rh, and regardless of whether they are used alone or in combination, they may be present in the form of each element in an amount of about 0.3 wt% to about 1 wt% based on the weight of the catalyst. Other (compound) forms of Pt and / or Rh may also be present, but preferably, non-elemental forms of Pt and / or Rh, or generally non-elemental forms of noble metals, are present independently in an individual amount of less than about 1 wt%, less than about 0.5 wt%, or less than about 0.1 wt% of the reforming / RWGS catalyst, or in a combined amount in the case of two or more noble metals.

[0061] In representative embodiments, one or two noble metals (e.g., Pt and / or Rh) are substantially the only one or two noble metals present in the reforming / RWGS catalyst, and for example, any other noble metal(s) may be present in an amount or total amount of less than about 0.1 wt%, or less than about 0.05 wt%, based on the weight of the catalyst. In further representative embodiments, one or two noble metals (e.g., Pt and / or Rh) are substantially the only metals present in the catalyst, excluding metals present in the solid support (e.g., for example, cerium is present as cerium oxide in the solid support). For example, any optional other metal(s) other than the one or two noble metals and the metal of the solid support may be present in an amount or total amount of less than about 0.1 wt%, or less than about 0.05 wt%, based on the weight of the catalyst. In some embodiments, a particular metal may be substantially absent from the catalyst, whether in elemental form or in compound form (e.g., in the form of an oxide as a metal oxide component of the solid support). For example, a particular metal may impart an undesired acidity to the solid support, show no substantial catalytic activity, or catalyze an undesired reaction. In certain embodiments, the solid support is substantially free of one or more of Si, Ti, Zr, Mg, Ca, Fe, V, Cr, Ni, W, and Sr. For example, these metals may be present in individual amounts of less than about 0.5 wt%, less than about 0.1 wt%, or less than about 0.05 wt% of the reforming / RWGS catalyst or the solid support of the catalyst, or in combined amounts in the case of two or more such metals. For example, one or more of Si, Zr, Mg, Ni may be present in individual or combined amounts. Any metal, including the noble metal(s) present in the catalyst, may generally have a metal particle size in the range of about 0.3 nanometers (nm) to about 20 nm, typically about 0.5 nm to about 10 nm, and in many cases about 1 nm to about 5 nm.

[0062] The noble metal(s) can be incorporated into the solid support according to known catalyst preparation techniques such as sublimation, impregnation, or dry mixing. In the case of impregnation, which is a preferred technique, an impregnation solution of soluble compounds of one or more noble metals in a polar (aqueous) or non-polar (e.g., organic) solvent can be contacted with the solid support, preferably under an inert atmosphere. For example, this contact can be carried out, preferably with stirring, in an ambient atmosphere of nitrogen, argon, and / or helium, or otherwise in a non-inert atmosphere such as air. Next, the solvent can be evaporated from the solid support using heating, gas flow, and / or vacuum conditions, etc., leaving a dried noble metal-impregnated support. The noble metal(s) can be impregnated into the solid support when a single noble metal (e.g., Pt) is impregnated, or when two noble metals are impregnated simultaneously and both are dissolved in the same impregnation solution, or otherwise when different impregnation solutions and contact steps are used (e.g., sequentially). In any case, the noble metal-impregnated support can be washed with a solvent to remove excess noble metal(s) and impurities, and further subjected to additional preparation steps such as drying, calcination, etc., to obtain a reforming / RWGS catalyst.

[0063] The solid support itself can be prepared according to known methods such as extrusion to form cylindrical particles (extrudates) or oil dropping or spray drying to form spherical particles. Regardless of the specific shape of the solid support and the resulting catalyst particles, the amount of noble metal(s) present in the catalyst as described above refers to the average noble metal(s) weight in a given catalyst particle (e.g., any optional shape such as cylindrical or spherical) regardless of the specific distribution of the noble metal(s) within the particle. In this regard, it can be understood that different preparation methods result in different distributions, such as predominantly depositing the noble metal(s) on or near the surface of the solid support or uniformly distributing the noble metal(s) throughout the solid support. Generally, the weight percentages described herein are based on the weight of the solid support or on the weight of the catalyst and can refer to the weight percentage of a single catalyst particle, but more generally refer to the average weight percentage of a number of catalyst particles, such as the number in a catalyst bed within a reactor used in the first or initial stage for performing reforming and / or RWGS. Reforming / RWGS conditions

[0064] In the first or initial stage, the reforming and / or RWGS reaction, preferably both simultaneously, is carried out by continuously contacting the gaseous feed mixture, preferably using a flowing stream of the gaseous feed mixture to improve process efficiency, with the reforming / RWGS catalyst described herein. For example, the contacting can be carried out by continuously flowing the gaseous feed mixture through a reactor (sometimes referred to as a reforming / RWGS reactor) containing the noble metal-containing reforming / RWGS catalyst described herein. The reactor is maintained under reforming / RWGS conditions. Reforming / RWGS conditions are the conditions within the reactor vessel, more specifically, the conditions within the bed of the reforming / RWGS catalyst contained within the vessel. These conditions include the temperature, pressure, and flow rate for effectively converting methane, and optionally other hydrocarbons, to hydrogen if such conditions are used for performing reforming. Alternatively, preferably in combination, these conditions are effective for converting CO 2 to CO, thereby carrying out the RWGS reaction.

[0065] Reforming / RWGS conditions useful for one or both of these reactions generally include temperatures from about 649 °C (1200 °F) to about 927 °C (1700 °F), typically from about 725 °C (1337 °F) to about 900 °C (1652 °F), and in many cases from about 750 °C (1382 °F) to about 880 °C (1616 °F). In preferred embodiments, the processes described herein, due to the high activity of the catalyst, can effectively reform (oxidize) the hydrogen sources described herein (e.g., CH 4 and / or perhaps C 2 H 6 and / or C 3 H 8 and other hydrocarbons such as) and / or perform the RWGS reaction at significantly lower temperatures compared to the typical representative reforming temperature of 816 °C (1500 °F). For example, reforming / RWGS conditions can include temperatures in the range of about 677 °C (1250 °F) to about 788 °C (1450 °F), or about 704 °C (1300 °F) to about 760 °C (1400 °F). When CO 2 is included as an oxidant for reforming in the gaseous feed mixture and H 2 O and / or O 2 is present in relatively small amounts or not at all, higher temperatures such as about 843 °C (1550 °F) to about 1010 °C (1850 °F), or about 885 °C (1625 °F) to about 941 °C (1725 °F) can be used in the case of dry reforming. When H 2 S and / or other sulfur-containing contaminants are present at significant concentrations (e.g., 100 - 1000 molar ppm), the desired conversion level (e.g., greater than about 85% CH 4To maintain the (conversion), it may be necessary to increase the temperature, for example, in the range of about 732 °C (1350 °F) to about 843 °C (1550 °F), or in the range of about 760 °C (1400 °F) to about 816 °C (1500 °F). Advantageously, it has been discovered that the compensating effect of increasing the temperature in response to an increase in the sulfur concentration in the gaseous feed mixture does not adversely affect the stability of the catalyst. That is, with respect to a comparison between a baseline sulfur-free operation and a sulfur-containing operation carried out at a higher compensating temperature, the overall catalyst life does not essentially change.

[0066] Particularly in the case of large-scale operations, the reactor operates with limited heat release to the surroundings (e.g., in the case of adiabatic operation), and the catalyst bed temperature can change as a particular reaction proceeds (e.g., the fixed bed temperature profile can be characterized by a profile that increases or decreases along the axial length of the reactor for exothermic or endothermic reactions, respectively). Thus, the temperatures associated with the reforming / RWGS conditions shown here, or other downstream FT reaction conditions and / or cracking reaction conditions, should be understood to mean the average (or weighted average) catalyst bed temperature. However, considering the high activity of the catalyst compositions described herein, particularly the reforming / RWGS catalysts, the temperatures described herein, particularly those associated with the reforming / RWGS conditions, can be the maximum or peak catalyst bed temperature in some embodiments.

[0067] Still other reforming / RWGS conditions can include pressures above atmospheric pressure, i.e., pressures greater than 0 kPa (0 psig) gauge pressure (equivalent to an absolute pressure of 101 kPa (14.7 psia)). In the reforming reaction, since the number of moles of the product is greater than the number of moles of the reactants, in some cases, equilibrium can be maintained at relatively low pressures. Representative reforming / RWGS conditions can generally include a gauge pressure of about 0 kPa (0 psig) to about 2.00 MPa (290 psig), typically about 100 kPa (15 psig) to about 1.50 MPa (218 psig), and in many cases about 500 kPa (73 psig) to about 1.00 MPa (145 psig). According to some embodiments, for example, it may be desirable to operate at higher pressures in the range of about 207 kPa (30 psig) to about 5.2 MPa (750 psig), for example about 1.4 MPa (200 psig) to about 3.4 MPa (500 psig). For example, the pressure P リサイクル of the gaseous effluent recycled from a downstream FT reaction or optional wax cracking or isomerization may exceed 2.1 MPa (300 psig), and in such cases, to minimize the energy loss associated with reducing the pressure of such a recycle stream, the reforming / RWGS pressure can be increased to approach or equal P リサイクル (e.g., the reforming / RWGS reactor pressure is at least 50% of P リサイクル or at least 75% of P リサイクル or 90% of P リサイクル or at least 95% of リサイクル ). Representative reforming / RWGS conditions can further generally include about 0.05 hours -1 to about 10 hours -1 , typically about 0.1 hours -1 to about 8.0 hours -1 , and in many cases about 0.5 hours -1 to about 5.0 hours -1The WHSV may be included. As understood in the art, WHSV is the weight flow rate of the gaseous feed mixture (or all inputs to one or more reactors used in the reforming or RWGS stage, or the total weight flow rate of the components of the gaseous feed mixture as described above) divided by the total weight of the catalyst in the reforming / RWGS reactor(s), representing the equivalent catalyst bed weight of the gaseous feed mixture (or all inputs or components) processed per hour. WHSV is related to the reciprocal of the reactor residence time. The reforming / RWGS catalyst may be included in the reactor(s) in the form of a fixed bed, but other catalyst systems such as a moving bed system or a fluidized bed system, which are advantageous in processes using continuous catalyst regeneration, may also be used. Regardless of the specific bed configuration, the catalyst bed preferably comprises individual particles of the reforming / RWGS catalyst rather than a monolithic catalyst. For example, such individual catalyst particles may have a spherical or cylindrical diameter of less than about 10 mm, often less than about 5 mm (e.g., about 2 mm or about 3 mm). In the case of cylindrical catalyst particles (e.g., extruded), they may have an equivalent length dimension (e.g., about 1 mm to about 10 mm, e.g., about 5 mm).

[0068] Advantageously, at any of the above temperature ranges, for a gaseous feed mixture containing CH 4 conversion of at least about 60% (e.g., about 60% to about 99%), at least about 75% (e.g., about 80% to about 99%), at least about 85% (e.g., about 85% to about 99%), or at least about 90% (e.g., about 90% to about 97%) of this component can be achieved due to the high activity of the catalyst. The desired conversion level for a given gaseous feed mixture and reforming / RWGS catalyst can be achieved or controlled by adjusting the temperature of the specific reactor or catalyst bed and / or other reforming / RWGS conditions (e.g., WHSV and / or pressure), as can be understood by a person skilled in the art using the knowledge obtained from the present disclosure. Advantageously, the noble metal-containing catalyst described herein can achieve a significant CH 4It may have sufficient activity to achieve stable conversion. In the case of dry reforming, for example, the oxidant for reforming (depending on the composition of the gaseous feed mixture) is mainly, substantially all, or all CO as described above. 2 When it is, such CH 4 conversion levels can be achieved at higher temperatures, for example up to about 918 °C (1685 °F), or in some cases up to about 885 °C (1625 °F) (e.g., as the peak or maximum catalyst bed temperature). As is understood in the art, the conversion rate of CH 4 can be calculated based on the following formula. 100*(CH4 原料 -CH4 生成物 ) / CH4 原料 Here, CH4 原料 is the total amount of CH 4 in the gaseous feed mixture (or the total amount in all inputs or all gaseous feed mixture components) supplied to one or more reactors used in the reforming stage or the RWGS stage, and CH4 生成物 is the total amount of CH 4 in the syngas intermediate obtained from this stage. In the case of a continuous process, these total amounts can be more conveniently expressed as flow rates, or total amounts per unit time (e.g., total weight / hour or total moles / hour). Instead of CH 4 in the gaseous feed mixture, C 4 which may more preferably be present in combination with CH 2 H 6 and / or C 3 H 8 and other hydrocarbons such as can achieve the same or higher levels of conversion. These C 2 and / or C 3 hydrocarbons are generally more easily converted to the syngas intermediate compared to CH 4 under certain reforming / RWGS conditions. The conversion of C 2 H 6 and / or C 3 H 8 is the same as that of CH 4can be determined by a process similar to the process described above with respect to the determination of the conversion. These CH 4 、C 2 H 6 、and / or C 3 H 8 conversion levels may be based on the "per pass" conversion achieved by passing through the reforming / RWGS stage (e.g., the reforming / RWGS reactor at this stage) once, or may be based on the overall conversion achieved by recycling a portion of the FT synthesis effluent or the polishing effluent back to the reforming / RWGS stage (e.g., the reforming / RWGS reactor at this stage) as described herein. In this regard, (i) the fraction rich in H 2 and CO 2 , or (ii) the recycled portion of the fraction rich in a hydrogen source and CO 2 (or a portion of such fraction (i) or (ii)) may contain unconverted CH 4 、C 2 H 6 and / or C 3 H 8 that can be continuously passed through the first reaction stage for conversion, thereby improving the overall conversion rate of these light hydrocarbons. Similarly, the overall conversion rate of hydrocarbons can be increased compared to the per pass conversion rate by returning the hydrocarbon recycle, i.e., the hydrocarbon recycle obtained from all or part of the recycled portion of the FT synthesis effluent or the polishing effluent, i.e., a separated fraction (such as a separated fraction rich in hydrocarbons in the naphtha boiling range, also referred to as the naphtha boiling range hydrocarbon fraction). Since such fractions may contain CH 4 、C 2 H 6 and / or C 3 H 8、 , the use of hydrocarbon recycle can also improve the overall conversion rate of these light hydrocarbons.

[0069] The reforming reaction (e.g., the reforming of CH 4 、C 2 H 6 、and / or C 3 H 8 ) results in H 2When both H₂ and CO are produced, the concentrations of these components in the syngas intermediate (reformed product) can increase compared to the gaseous feed mixture (or combined input fed to one or more reactors used in the reforming or RWGS stage, or gas feed mixture components). If CO 2 is present in the gas mixture, the CO concentration can increase by the RWGS reaction alone or in combination with reforming. In this regard, the extent of the RWGS reaction in which H₂O is converted to H₂ and CO under equilibrium constraints is determined by a process similar to the process described above for the determination of CH₄ conversion, and the conversion of CO 2 in the reforming or RWGS stage can be characterized by being at least about 60%, at least about 70%, or at least about 80%. In some embodiments, depending on the H₂ 4 concentration in the gaseous feed mixture and the extent of the RWGS reaction, the concentration of CO can increase and the concentration of H₂ 2 can decrease. In representative embodiments, the syngas intermediate can contain CO in an amount of at least about 5 mol% (e.g., from about 5 mol% to about 50 mol%) or at least about 8 mol% (e.g., from about 8 mol% to about 35 mol%). In other embodiments, a high level of conversion of CH₄ 2 , C₂H₄, and / or C₂H₆ is achieved, and the syngas intermediate can contain a larger amount of CO, such as at least about 30 mol% (e.g., from about 30 mol% to about 65 mol%) or at least about 40 mol% (e.g., from about 40 mol% to about 55 mol%). In further representative embodiments, the syngas intermediate has an H₂ 2 content of at least about 30 mol% (e.g., from about 30 mol% to about 90 mol%) or at least about 40 mol% (e.g., from about 40 mol% to about 80%) with respect to the amount of gaseous feed mixture present, as well as the amounts of oxidants CO 4 and H₂O present (which react with, for example, CH₄ 2 in a 1:1 and 3:1 H₂ 6 ratio, respectively). 3 H₂ 8 2 content of at least about 30 mol% (e.g., from about 30 mol% to about 90 mol%) or at least about 40 mol% (e.g., from about 40 mol% to about 80%) with respect to the amount of gaseous feed mixture present, as well as the amount of H₂ 2 present, and the amounts of oxidants CO 2 and H₂ 2 O present (which react with, for example, CH₄ 4 to produce H₂ 2 ​:Depending on the production of the stoichiometric molar ratio of CO), the H of the syngas intermediate 2 :The CO molar ratio can be from about 1.0 to about 7.0, for example, from about 4.0 to about 6.5 in the case of a high ratio. Otherwise, in the case of a lower ratio, the H of the syngas intermediate 2 :The CO molar ratio can be from about 1.0 to about 3.0, for example from about 1.8 to about 2.4, or from about 2.1 to about 2.7. According to still other embodiments, for example, most, substantially all, or all of the oxidizing agent is CO 2 is used to reform CH 4 , C 2 H 6 , and / or C 3 H 8 , considering only the stoichiometry of the dry reforming reaction, the H of the syngas intermediate 2 :The CO molar ratio can be smaller. For example, this H 2 :The CO molar ratio can be from about 0.5 to about 1.5, for example from about 0.8 to about 1.2. According to still other embodiments, the H of the syngas intermediate 2 :The CO molar ratio can be "adjusted" using the amount of H 2 O (steam) input into the gas mixture as a "handle". For example, to obtain a desired or setpoint H 2 :CO molar ratio, more or less H 2 can be added, but such setpoints are individual values within any of the above ranges. The operation of the reforming stage or the RWGS stage may include, for example, adjusting the H of the syngas intermediate 2 :The CO molar ratio to a value from about 2.1 to about 2.5, and the amount of steam input corresponding to a higher molar ratio increases. According to yet another embodiment, if the gas mixture includes a fresh feedstock further containing H 2 , adjusting the amount of such H 2 in such fresh feedstock can be another "handle" for "adjusting" the H of the syngas intermediate 2 :CO molar ratio, instead of or in combination with adjusting the amount of steam input into the gas mixture.

[0070] In any case, the above molar ratio can be a representative value of the syngas intermediate or a part thereof used in the Fischer-Tropsch synthesis, directly obtained from the reactor used in the reforming stage or the RWGS stage, or, before (e.g., upstream of) the Fischer-Tropsch synthesis stage, for example, by an intervening operation such as adding an H 2 source and / or a CO source to this intermediate or a part thereof, the H 2 :CO molar ratio can be obtained after adjustment. Representative sources of H 2 and / or CO are, as described herein, (i) a part of the Fischer-Tropsch synthesis effluent rich in H 2 and CO 2 , or (ii) a recycled part of a part of the Fischer-Tropsch synthesis effluent rich in a hydrogen source and CO 2 (or a part of such part (i) or (ii)). Another representative source of H 2 is purified hydrogen (e.g., by PSA or membrane separation), and another representative source of H2 and CO is unpurified hydrogen (e.g., syngas) obtained from steam methane reforming. In other embodiments, water can be removed (e.g., condensed) from the syngas intermediate or a part thereof used in the Fischer-Tropsch synthesis between (a) the reforming stage or the RWGS stage and (b) the Fischer-Tropsch synthesis stage. Fisher-Tropsch (FT) synthesis

[0071] As described above, after the first or initial reaction stage in which a syngas intermediate containing both H 2 and CO (i.e., an H 2 / CO mixture) is generated, a second stage may follow in which this syngas intermediate is converted to C 4 + hydrocarbons contained in the liquid hydrocarbon product. In the second stage, typically, Fischer-Tropsch (FT) synthesis is carried out, and high molecular weight hydrocarbons are produced according to the following reaction. (2n + 1)H 2 + nCO → C n H 2n+2 + nH 2 O Specifically, the FT synthesis reaction can be used to produce alkane hydrocarbons having two or more carbon atoms with a specific carbon number distribution as described above. Representative processes may include the step of converting all or a portion of the syngas intermediate via FT synthesis, and optionally, performing one or more intervening operations on this intermediate to provide an FT feedstock having a composition and / or properties different from those of the syngas intermediate. Such intervening operations may include cooling, heating, pressurization, depressurization, separation of one or more components (e.g., removal of condensed water), addition of one or more components (e.g., addition of H 2 :CO molar ratio to that of the syngas intermediate), and / or reaction of one or more components (e.g., reaction of H 2 and / or CO using another water gas shift reaction or reverse water gas shift reaction), and these operations (plural) are performed on the syngas intermediate to supply the FT feedstock to the FT reactor(s) of the FT synthesis stage. Comparing the temperature and pressure normally used in the FT reactor(s) of the FT synthesis stage with the temperature and pressure used in the reactor(s) of the reforming stage or RWGS stage, the syngas intermediate can be cooled, separated from condensed water, and pressurized. In some embodiments, these can be the only intervening operations that the syngas intermediate undergoes to provide the FT feedstock. In other embodiments, cooling and pressurization can be the only intervening operations. In still other embodiments, intervening operations that can be omitted include drying the syngas intermediate to remove vapor phase H 2 O (thus, this can include, for example, using an adsorbent selective for water vapor such as a 5A molecular sieve, which is different from the condensation of liquid phase H 2 O) and / or removing CO 2 in accordance with a conventional acid gas treatment step (e.g., amine scrubbing). In still other embodiments, the intervening operation is (i.e., the syngas intermediate or a portion thereof) (i) a portion of the FT synthesis effluent rich in H 2 and 2 or (ii) a hydrogen source and CO 2 2 ​It may be the addition of a portion of the FT synthesis effluent rich in (or a portion of (i) or (ii), such as its recycled portion). According to some embodiments, CO 2 removal can be carried out on the syngas intermediate upstream of the FT synthesis stage (e.g., as an intervening operation). Preferably, water generated in the reforming stage or the RWGS stage reactor(s) is condensed from the syngas intermediate before the FT reactor(s), and / or preferably, the H 2 :CO molar ratio of the syngas intermediate is not adjusted. Not using, restricting, and / or omitting intervening operations or omitting specific intervening operations between the reforming stage or the RWGS stage and the FT synthesis stage has the advantage of simplifying the overall process of producing liquid hydrocarbon products.

[0072] The conditions of the FT synthesis stage, more specifically the FT reactor(s) used in this stage, are suitable for the conversion of H 2 and CO to C 4 + hydrocarbons. In a representative embodiment, suitable FT reaction conditions for use in at least one FT reactor, or more specifically, the catalyst bed contained in such a reactor, may include an FT reaction temperature in the range of about 121 °C (250 °F) to about 288 °C (550 °F), or about 193 °C (380 °F) to about 260 °C (500 °F). The FT reaction pressure includes a gauge pressure of about 621 kPa (90 psig) to about 5.00 MPa (725 psig), or a gauge pressure of about 2.50 MPa (362 psig) to about 3.50 MPa (508 psig).

[0073] In the FT reactor(s), the FT feedstock, which represents all or a portion of the syngas intermediate, may optionally be contacted with a suitable FT catalyst (e.g., a bed of FT catalyst particles disposed within the FT reactor) under FT reaction conditions that may include the temperature and / or pressure described above, after one or more intervening operations described above. Representative FT catalysts include one or more transition metals selected from cobalt (Co), iron (Fe), ruthenium (Ru), and nickel (Ni) as the FT active metal(s). Preferred FT catalysts include generally at least about 5 wt% of the transition metal(s), typically from about 5 wt% to about 15 wt% of the transition metal(s), and often at least about 15 wt% of the transition metal(s) on a solid support. The phrase "on a solid support" is intended to encompass catalysts in which the active metal(s) is / are on the support surface and / or within the porous internal structure of the support. Representative solid supports include one or more metal oxides selected from the group consisting of aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, strontium oxide, etc. The solid support may comprise all or substantially all (e.g., greater than about 95 wt%) of one or more such metal oxides. Preferred FT catalysts include the above amount (e.g., at least about 10 wt%) of the transition metal cobalt (Co) on a support comprising aluminum oxide (alumina).

[0074] The FT catalysts and FT reaction conditions described herein are generally suitable for achieving a conversion of at least about 20% (e.g., from about 20% to about 99% or from about 20% to about 75%), at least about 30% (e.g., from about 30% to about 95% or from about 30% to about 65%), or at least about 50% (e.g., from about 50% to about 90% or from about 50% to about 85%) of 2 and / or CO (H 2 conversion or CO conversion). These FT conversion levels can be based on H 2 conversion or CO conversion, depending on which reactant is stoichiometrically limiting in the FT feedstock or syngas intermediate, considering the FT synthesis reaction chemistry, and these FT conversion levels are for CH 4The determination of the conversion can be made by a process similar to the process described above regarding the determination of the conversion. Preferably, these FT conversion levels are based on the CO conversion. These FT conversion levels may be based on the "per pass" conversion achieved by passing through the FT synthesis stage (e.g., the FT reactor at this stage) once, or, as described herein, may be based on the overall conversion achieved by returning the recycled portion of the FT product to the FT synthesis stage (e.g., the FT reactor at this stage).

[0075] The desired H in the FT reactor(s) 2 The conversion rate and / or the CO conversion rate can be achieved by adjusting the above-described FT reaction conditions (e.g., the FT reaction temperature and / or the FT reaction pressure) and / or by adjusting the weight hourly space velocity (WHSV) defined above. The FT reaction conditions generally include a weight hourly space velocity (WHSV) of from about 0.01 h -1 ~ about 10 h -1 , typically from about 0.05 h -1 ~ about 5 h -1 , often from about 0.3 h -1 ~ about 2.5 h -1 are included. The conversion level (e.g., CO conversion) can be increased, for example, by increasing the pressure and decreasing the WHSV, which respectively result in an increase in the reactant concentration and the reactor residence time. The FT reaction conditions may optionally include returning the recycled portion of the FT product exiting the FT reactor to the FT feedstock (or in some cases the syngas intermediate) and combining it with the FT feedstock (or in some cases the syngas intermediate), or returning it to the FT reactor itself. By the recycling operation, the "per pass" conversion rate when passing through the FT reactor can be kept relatively low, and the overall conversion rate is increased by recycling. In some embodiments, this low per pass conversion rate can advantageously limit the amount of high molecular weight hydrocarbons (e.g., normal C 20 + hydrocarbons) that can be produced as part of the hydrocarbon product distribution obtained from the FT synthesis reaction.

[0076] However, preferably, the FT reaction conditions involve relatively little or no recycling of the FT products. For example, the FT reaction conditions include the weight ratio of recycled FT products to FT feedstock (i.e., the "recycle ratio"), and this recycled FT product and FT feedstock (e.g., all or part of the syngas intermediate) together form a composite feedstock to the FT reactor, generally less than about 1:1, typically less than about 0.5:1, and in many cases less than about 0.1:1. In some cases, the recycle rate can be zero, which means that no recycling of the FT products is used and the per-pass conversion is equal to the overall conversion. At such low recycle rates, from the perspective of process efficiency and economy, the per-pass H 2 conversion rate or CO conversion rate is relatively high, for example at least about 50% (e.g., about 50% - about 95%), at least about 60% (e.g., about 60% - about 92%), or at least about 70% (e.g., about 70% - about 90%). As the per-pass conversion level increases, the hydrocarbon distribution in the FT products often shifts to those with an increasing number of carbon atoms.

[0077] Accordingly, embodiments of the present invention relate to a process for producing liquid hydrocarbon products from syngas containing H 2 and CO, such as a syngas intermediate, or an FT feedstock obtained after one or more intervening operations performed on this intermediate as described above. The syngas intermediate or FT feedstock can generally be produced by a reforming reaction and / or RWGS reaction as described above. This process includes contacting the syngas with a catalyst comprising, on a solid support (e.g., alumina, etc.), at least about 5 wt% Co, such as about 5 wt% - about 15 wt% Co, or at least about 10 wt% Co, and / or optionally other transition metal(s). This process includes converting H 2 and CO in the syngas to hydrocarbons containing C 4 + hydrocarbons.

[0078] Advantageously, since there is no recycling of the FT products, compression costs can be saved and the overall design of the integrated process can be simplified. This includes an increase in the conversion rate per pass and, associated therewith, the normal C that is solid at room temperature and obtained as an undesirable wax fraction 20 + To the extent that a shift in the distribution of hydrocarbons in the FT products to those with a higher number of carbon atoms, including hydrocarbons, is required, aspects of the present invention relate to the discovery of an important, further downstream processing strategy for converting these hydrocarbons to C 4 ~C 19 hydrocarbons by cracking, thereby increasing the yield of liquid hydrocarbon products. In this regard, according to a typical process, the second stage of converting the syngas intermediate to C 4 + hydrocarbons includes a combination of FT synthesis and cracking, and in particular, converting the normal C obtained from FT synthesis 20 + hydrocarbons reduces the molecular weight of the hydrocarbons. The combination of wax cracking and isomerization can be particularly advantageous in the following respects compared to cracking alone. (a) Considering that some branched C 20 + hydrocarbons are desirable compared to linear (normal) hydrocarbons in that they do not contribute to undesirable waxes, substantially removing all of the normal C 20 + hydrocarbons, and (b) improving the properties of the liquid hydrocarbon products, such as by lowering the freezing point of the jet and diesel fractions, by generating C 4 ~C 19 hydrocarbons with an increased degree of branching of the molecular structure. FT synthesis (with optional downstream or in-situ cracking)

[0079] According to the above description, C 4 +A liquid hydrocarbon product containing hydrocarbons can be obtained after the step of converting a synthesis gas intermediate via Fischer-Tropsch synthesis. For example, the liquid hydrocarbon product can be separated from the Fischer-Tropsch product corresponding to the Fischer-Tropsch synthesis effluent in terms of quantity and composition according to a preferred embodiment. More specifically, the liquid hydrocarbon product can be separated as a part of the Fischer-Tropsch synthesis effluent rich in hydrocarbons using techniques known in the art (e.g., phase separation and / or fractional distillation). Optionally, in a more specific embodiment according to the above description, the liquid hydrocarbon product can be obtained after the step of converting a synthesis gas intermediate via Fischer-Tropsch synthesis combined with cracking. Throughout the present disclosure, the term "cracking" is used to describe additional reactions occurring in situ to reduce the molecular weight of the C 4 + hydrocarbons as long as, in a preferred embodiment, the cracking catalysts described herein have cracking activity for these hydrocarbons and, optionally considering also isomerization, should be understood to encompass "cracking with isomerization", and these reactions are advantageous both in terms of reducing and / or removing hydrocarbons that are solid at room temperature (i.e., waxes) and in terms of increasing the branching of the molecular structure of the liquid hydrocarbons. Similarly, the term "polishing" includes additional cracking reactions and additional isomerization reactions occurring in another cracking or polishing reactor downstream of the Fischer-Tropsch reactor. 20 +

[0080] ​When liquid hydrocarbon products are obtained from a combination of FT synthesis and cracking, the latter reaction can be carried out either in a downstream cracking reactor and / or, in some cases, in the FT reactor itself, i.e., in situ. Thus, the liquid hydrocarbon product, which is part of the FT synthesis effluent, can more specifically be part of such an FT synthesis effluent obtained as the product of an FT reactor with in situ cracking. As noted above, whether in situ within the FT reactor or in another reactor downstream of the FT reactor, cracking is carried out in combination with isomerization and can remove wax from the liquid hydrocarbon product (when combined with isomerization, the branching of the molecular structure of the liquid hydrocarbon product increases). Wax can be present in the FT synthesis effluent in the absence of cracking (and optional isomerization). In this regard, another "cracking reactor" used to condition (reduce or remove wax) the liquid hydrocarbon product in this way before separation and / or recovery of the hydrocarbon fraction can be referred to as a "polishing reactor". Whether the FT synthesis effluent is obtained after only the FT synthesis reaction or after a combination of the FT synthesis reaction and in situ cracking (e.g., a combination of in situ cracking and in situ isomerization), the liquid hydrocarbon product is part of this FT synthesis effluent obtained from the FT reactor and can be separated therefrom. When cracking is carried out in another cracking or polishing reactor after FT synthesis, the liquid hydrocarbon product can be part of the polishing effluent. In this case, since the FT synthesis effluent is obtained after cracking in another cracking or polishing reactor, the product immediately downstream of the FT reactor (e.g., removed from this reactor) can be the FT synthesis effluent, the amount and composition of which can correspond to the cracking feedstock, or the feedstock to the cracking or polishing reactor (e.g., if no intervening operations are carried out between the FT reactor and the cracking or polishing reactor, the FT synthesis effluent and the cracking feedstock can be identical). 4 + Before separation and / or recovery of the hydrocarbon fraction, another "cracking reactor" used to condition (reduce or remove wax) the liquid hydrocarbon product in this way can be referred to as a "polishing reactor". Whether the FT synthesis effluent is obtained after only the FT synthesis reaction or after a combination of the FT synthesis reaction and in situ cracking (e.g., a combination of in situ cracking and in situ isomerization), the liquid hydrocarbon product is part of this FT synthesis effluent obtained from the FT reactor and can be separated therefrom. When cracking is carried out in another cracking or polishing reactor after FT synthesis, the liquid hydrocarbon product can be part of the polishing effluent. In this case, since the FT synthesis effluent is obtained after cracking in another cracking or polishing reactor, the product immediately downstream of the FT reactor (e.g., removed from this reactor) can be the FT synthesis effluent, the amount and composition of which can correspond to the cracking feedstock, or the feedstock to the cracking or polishing reactor (e.g., if no intervening operations are carried out between the FT reactor and the cracking or polishing reactor, the FT synthesis effluent and the cracking feedstock can be identical).

[0081] When the FT synthesis effluent is obtained after the FT synthesis reaction combined with in-situ cracking, the "FT product" includes the hydrocarbons present in the FT synthesis effluent, but different from the FT synthesis effluent, it is the hydrocarbons obtained only from FT synthesis (without cracking), especially the wax fraction (e.g., normal C 20 + hydrocarbons) and can be regarded as a virtual (or temporary intermediate) product. The wax fraction is converted to normal or branched C 4 ~C 19 hydrocarbons in the FT synthesis effluent and contributes to the yield of the liquid hydrocarbons present in the FT synthesis effluent. Therefore, the FT product can correspond to the FT synthesis effluent when the FT reactor is operating without in-situ cracking.

[0082] As will be understood by those skilled in the art, using the knowledge obtained from the present disclosure, optional and additional separation and / or reaction (e.g., cracking) steps can be respectively performed to (i) increase the concentration of C 4 + hydrocarbons in the liquid hydrocarbon product, and / or (ii) increase the yield of C 4 + hydrocarbons obtained from the carbon in the gaseous feed mixture, as a result, the total yield of the liquid hydrocarbon product can be increased. According to a particular embodiment, the hydrocarbon product or fraction (e.g., after separation from the FT synthesis effluent or the polished effluent) can contain at least about 60 wt% (e.g., about 60 wt% to about 100 wt%), at least about 90 wt% (e.g., about 90 wt% to about 100 wt%), or at least about 95 wt% (e.g., about 95 wt% to about 99 wt%) of the total amount of liquid hydrocarbons. Along with or instead of such a total amount, the hydrocarbon product or fraction can be (i) hydrocarbons characteristic of naphtha or gasoline boiling range hydrocarbons, such as C 4 ~C 9 hydrocarbons, (ii) hydrocarbons characteristic of jet fuel boiling range hydrocarbons, such as C 9 ~C 16 hydrocarbons, and / or (ii) hydrocarbons characteristic of diesel boiling range hydrocarbons, such as C16 ~C 25 The hydrocarbon may be included in an amount of at least about 25 wt% (e.g., from about 25 wt% to about 85 wt%), at least about 40 wt% (e.g., from about 40 wt% to about 80 wt%), or at least about 50 wt% (e.g., from about 50 wt% to about 75 wt%). In other specific embodiments (e.g., H 2 / CO 2 -rich fraction or recycling of a hydrocarbon / CO 2 -rich fraction in combination with cracking), at least about 40% (e.g., from about 40% to about 95%), at least about 55% (e.g., from about 55% to about 95%), or at least about 70% (e.g., from about 70% to about 95%), or at least about 80% (e.g., from about 80% to about 99%) of the feed carbon content of the gaseous feed mixture (e.g., the carbon content of CH 4 and / or CO 2 present in this mixture) forms liquid hydrocarbon products. These percentages are equivalently expressed in wt% or mol%.

[0083] According to a further embodiment, recycling of a separated fraction of the liquid hydrocarbon product, e.g., in particular a separated fraction rich in C 4 + hydrocarbons, e.g., (i) hydrocarbons in the naphtha or gasoline boiling range (i.e., "hydrocarbon fraction in the naphtha boiling range"), (ii) hydrocarbons in the jet fuel boiling range (i.e., "hydrocarbon fraction in the jet fuel boiling range"), or (iii) hydrocarbons in the diesel boiling range (i.e., "hydrocarbon fraction in the diesel boiling range") rich separated fraction may be used to change the product slate of the C 4 + hydrocarbons recovered from the process, which corresponds to the product yield of the process. In this regard, any of the liquid hydrocarbon products (e.g., C 4 +A specific process that is not recycled into the hydrocarbon, e.g., that present in the separated fraction) can be carried out, as a result of which hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and hydrocarbons in the diesel boiling range are recovered or removed as the output of the process (e.g., as a separated fraction). In this case, the recovered C 4 + The hydrocarbons contain at least about 55 wt% of hydrocarbons in the jet fuel boiling range, and all or substantially all of the remainder contains a combination of hydrocarbons in the naphtha boiling range and hydrocarbons in the diesel boiling range. For example, the recovered C 4 + The hydrocarbons can contain at least about 40 wt% of a combination of hydrocarbons in the naphtha boiling range and hydrocarbons in the diesel boiling range. However, other specific processes can be carried out by recycling the C 4 + hydrocarbons, e.g., by recycling all or part of a specific separated fraction, reducing or eliminating the yield of the type of hydrocarbon being recycled and instead favoring other types of hydrocarbons. For example, without recycling the liquid hydrocarbons, the recovered C 4 + Compared to the yield of the hydrocarbons, when hydrocarbons in the naphtha boiling range (e.g., present in the separated fraction) in the liquid hydrocarbon product are recycled into the process, the recovered C 4 + The hydrocarbons contain at least about 80 wt% of hydrocarbons in the jet fuel boiling range, and the hydrocarbons in the diesel boiling range can account for all or substantially all of the remainder. For example, the recovered C 4 + The hydrocarbons can contain at least about 15 wt% of hydrocarbons in the diesel boiling range.

[0084] More generally, an optional hydrocarbon fraction can be recycled to increase the yield of one or more other hydrocarbon fractions while decreasing the yield of that hydrocarbon fraction. For example, a process operating at a high yield of hydrocarbons in the jet fuel boiling range can, if desired, recycle all or substantially all of the hydrocarbons in the naphtha boiling range and the hydrocarbons in the diesel boiling range (e.g., present in the separated fractions), while simultaneously recovering and removing all or substantially all of the hydrocarbons in the jet fuel boiling range from the process. This operational flexibility is advantageously provided in the reforming / RWGS catalysts described herein in terms of the surprising "robustness" for converting unwanted hydrocarbon moieties that can be recycled in the first stage of the process. This is different from the characteristics of conventional reforming catalysts that lack the ability to stably convert heavy hydrocarbon fractions such as hydrocarbons in the diesel boiling range. The operation involving the recycling of specific hydrocarbon fractions provides a simple and direct strategy for managing (increasing or decreasing) the overall process selectivity for specific hydrocarbons.

[0085] Those skilled in the art, based on the knowledge obtained from the present disclosure, will more generally understand how recycling various types of C 4 + hydrocarbons affects the yields of these various types and other types of C 4 + hydrocarbons recovered from the process. Importantly, the use of cracking as described herein provides yet another mechanism by which hydrocarbon yields can be managed, in this case by 20 + reducing or removing hydrocarbons. In some embodiments, for example, the recovered C 4 + hydrocarbons are hydrocarbon / CO in combination with cracking 2Recycling of the fraction rich in it can consist of, or can consist essentially of, any one or more of hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range (e.g., not including hydrocarbons having less than 4 carbon atoms or more than 20 carbon atoms). In other embodiments, the recovered C 4 + hydrocarbons are combined with cracking and the recycling of the fraction rich in hydrocarbons / CO 2 Recycling of the fraction rich in it and recycling of hydrocarbons in the naphtha boiling range can consist of, or can consist essentially of, hydrocarbons in the jet fuel boiling range and / or hydrocarbons in the diesel boiling range (e.g., not including hydrocarbons having less than 9 carbon atoms or more than 20 carbon atoms).

[0086] Separate from the FT reactor, an optional downstream cracking or finishing reactor can, as described above, add to the FT synthesis effluent downstream of the FT reactor a substantial amount (e.g., at least about 1 wt%, at least about 5 wt%, at least about 10 wt%, or at least about 20 wt%) of normal C 4 + hydrocarbons (e.g., C 4 ~C 19 hydrocarbons) that can be cracked to increase the overall yield of C 20 +Embodiments containing hydrocarbons may be desirable. Such cracking or polishing reactors, as described above, can be combined with in-situ wax cracking in the FT reactor, although some wax may remain in the FT synthesis effluent even after in-situ cracking. The cracking or polishing feedstock to the downstream cracking or polishing reactor can include some or all of the FT synthesis effluent and, optionally, can be followed by one or more intervening operations such as cooling, heating, pressurization, depressurization, separation of one or more components, addition of one or more components, and / or reaction of one or more components. Considering the temperatures and pressures typically used in the cracking or polishing reactor(s) of the FT synthesis stage compared to those used in the FT reactor(s) of this stage, the FT synthesis effluent can be heated to a temperature suitable for the cracking or polishing reactor, as described herein, prior to cracking or polishing. In some embodiments, this heating can be the only intervening operation applied to the FT synthesis effluent to provide the cracking or polishing feedstock. Alternatively, to further simplify and enhance the efficiency of the operation, considering that the FT reaction conditions can include a temperature that is the same as or substantially the same (e.g., within about 10 °C (18 °F)) as the temperature used in the downstream cracking or polishing reactor (e.g., within the temperature range described below for the cracking or polishing reaction conditions), even this heating can be omitted. In other embodiments, it has been found advantageous for the cracking or polishing reaction conditions to include the same or substantially the same pressure as described above with respect to the FT reaction conditions, so the intervening operations that can be omitted include pressurization and depressurization. For example, the pressure in the cracking reactor or polishing reactor will be the same as the pressure in the upstream FT reactor, although the pressure will drop due to the nominal pressure drop associated with the piping and other process equipment between these reactors. Thus, the cost associated with pressurizing (compressing) or depressurizing (expanding) the FT synthesis effluent upstream of the cracking or polishing reactor can be advantageously avoided.Similar to the intervening operations between the reforming or RWGS stage and the FT synthesis stage, omitting, restricting, and / or eliminating certain intervening operations that do not use intervening operations between the FT reactor and the cracking or polishing reactor of the FT synthesis stage provides advantages related to the overall simplification of the integrated process. For example, special advantages are obtained when all or substantially all of the syngas intermediate is used as the FT feedstock and / or all or substantially all of the FT synthesis effluent is used as the cracking or polishing feedstock. In other embodiments, all or substantially all of the syngas intermediate (e.g., excluding the condensed moisture-containing portion) is used as the FT feedstock and / or all or substantially all of the FT synthesis effluent is used as the cracking or polishing feedstock.

[0087] Accordingly, the conditions within the cracking or polishing reactor(s) convert normal C that is solid at room temperature 20 + hydrocarbons to additional hydrocarbons that are liquid at room temperature, particularly C 4 ~C 19is suitable for conversion to hydrocarbons. Since cracking is commonly carried out to convert the wax portion of the hydrocarbons obtained from FT synthesis, the terms (i) "wax cracking", "wax cracking reactor", "wax cracking conditions", etc. are used herein in place of, or interchangeably with, the terms (i) "cracking", "polishing", "(ii) cracking reactor", "polishing reactor", "(iii) cracking conditions", "polishing conditions", etc. The cracking reactor or polishing reactor can be incorporated into the FT reactor, for example, immediately after the FT catalyst bed in a single vessel, or by using at least a downstream cracking catalyst bed or polishing catalyst bed, or otherwise by dispersing two types of catalysts in a single vessel. Alternatively, or in combination, the use of at least one separate cracking or polishing reactor (e.g., as a separate cracking reaction vessel) is preferred, whereby the cracking reaction conditions can be maintained independently of the FT reaction conditions as described above. A separate cracking reactor or polishing reactor can be advantageous, for example, (i) when maintaining some or all of the cracking catalyst or polishing catalyst used in the FT synthesis stage in a different reactor type compared to the FT reactor, for example, when maintaining the cracking catalyst or polishing catalyst in a fixed bed reactor which typically has a simpler design compared to the FT reactor as it does not usually have the same design constraints in terms of the ability to remove reaction heat, (ii) when removing and / or replacing the cracking catalyst or polishing catalyst at a time that does not necessarily coincide with the removal and / or replacement of the FT catalyst (e.g., different intervals for the removal and / or replacement of the FT catalyst), and / or (iii) when operating the cracking catalyst or polishing reactor at a different temperature (e.g., a higher temperature) or other different conditions compared to the FT reactor. The term "cracking catalyst" can refer to, but does not necessarily have to be, a catalyst having cracking activity and optionally isomerization activity contained in situ within the FT reactor. On the other hand, the term "polishing catalyst" can refer to, but does not necessarily have to be, a catalyst having cracking activity and / or isomerization activity contained in another "polishing reactor" downstream of the FT reactor.When using the "cracking catalyst" in-situ in the FT reactor and using both one or more "polishing catalysts" in a separate polishing reactor, such polishing catalysts can have the same composition as the cracking catalyst and / or the same shape (e.g., spherical or cylindrical) as the cracking catalyst. More generally, any optional FT catalyst or cracking catalyst can independently have the shape and / or dimensions described above for the reforming / RWGS catalyst. The polishing reactor may contain at least two catalysts, one having wax cracking activity (and optionally isomerization activity) and the other having isomerization activity (and optionally wax cracking activity), or may contain one catalyst having only wax cracking activity, only isomerization activity, or both wax cracking activity and isomerization activity. If the designs of the FT reactor and the polishing reactor are different and thus different reaction conditions are presented for the catalysts contained therein, the cracking catalyst can have a different composition and / or morphology from any of the one or more polishing catalysts having wax cracking activity.

[0088] Regarding the use of a separate cracking or hydrocracking reactor, considering the wide carbon number distribution of the hydrocarbons produced from FT synthesis, it can be important to maintain the FT synthesis effluent (or at least a portion of this effluent used in the cracking or hydrocracking reactor) at an elevated temperature from the outlet of the FT reactor (effluent) to the inlet of the cracking or hydrocracking reactor to avoid condensation of liquid hydrocarbons and / or deposition of solid hydrocarbons. Such condensation and / or deposition can be prevented if all or substantially all of the FT synthesis effluent is maintained in the gas phase from the outlet of the FT reactor to the inlet of the cracking or hydrocracking reactor. For example, the FT synthesis effluent can be maintained at a temperature of at least about 66 °C (150 °F), at least about 121 °C (250 °F), at least about 216 °C (420 °F), or at least about 327 °C (620 °F) from the outlet of the FT reactor to the inlet of the cracking or hydrocracking reactor, such as when heating the FT synthesis effluent from this temperature to a temperature representative of cracking or hydrocracking reaction conditions as described herein. Such temperatures (suitable for use in at least one cracking or hydrocracking reactor) can range from about 200 °C (392 °F) to about 400 °C (752 °F), or from about 225 °C (437 °F) to about 300 °C (572 °F). Other cracking reaction conditions can include a gauge pressure of from about 621 kPa (90 psig) to about 5.00 MPa (725 psig), or from about 2.50 MPa (362 psig) to about 3.50 MPa (508 psig).

[0089] In a cracking reactor or optional polishing reactor(s), the cracking feedstock can be contacted with a suitable cracking catalyst or isomerization catalyst (e.g., a bed of cracking catalyst particles disposed within the cracking reactor) under cracking reaction conditions or polishing reaction conditions which may include the above temperatures and / or pressures. The cracking reaction is more specifically a hydrocracking reaction which, as understood in the art, refers to a reaction of hydrocarbons with hydrogen to produce hydrocarbons having fewer carbon atoms and as a result a lower molecular weight. Hydrocracking has an overall effect on the carbon number distribution of the cracking or polishing feedstock which may correspond to the carbon number distribution of the FT product or FT synthesis effluent, in particular the normal C 20 + hydrocarbons in the cracking feedstock which may be present in the FT product or FT synthesis effluent, reducing and in some cases removing the weight percent of the normal C 4 ~C 19 hydrocarbons and favoring C 20 + hydrocarbons as components of the liquid hydrocarbon product. As noted above, polishing may further include isomerization of normal C

[0090] hydrocarbons to branched hydrocarbons which do not contribute to undesirable waxes, and isomerization of liquid hydrocarbons to branched hydrocarbons which improve the properties of the liquid hydrocarbons, and these isomerization reactions may more specifically be hydrogen isomerization reactions. Considering the cracking or polishing reactor used to carry out hydrocracking and hydroisomerization, this cracking or polishing reactor is more generally regarded as a hydrotreating reactor, and the cracking or polishing catalyst contained in this reactor is more generally regarded as a hydrotreating catalyst.Since hydrogenation cracking reactions and, optionally, hydrogen isomerization reactions require hydrogen, in some embodiments, this hydrogen is present in the cracking or polishing feedstock and / or the FT synthesis effluent (or a portion thereof) that is input into the cracking or polishing reactor. For example, the hydrogen in the syngas intermediate that is not converted in the downstream FT reactor can operate the cracking reactor or the polishing reactor without the need to add an additional hydrogen source downstream of the cracking reactor or the polishing reactor or the FT reactor. According to some embodiments, hydrogen is at least about 5 mol% (e.g., about 5 mol% to about 55 mol%), at least about 10 mol% (e.g., about 10 mol% to about 45 mol%), or at least about 15 mol% (e.g., about 15 mol% to about 35 mol%), or at least about 20 mol% (e.g., about 20 mol% to about 40 mol%) without introducing additional hydrogen sources other than the hydrogen generated in the reforming stage or the RWGS stage and / or the hydrogen present in the syngas intermediate. These hydrogen concentrations can correspond to the hydrogen concentrations present in the FT synthesis effluent. According to other embodiments, a source of hydrogen replenishment added to the cracking reactor or the polishing reactor or upstream of such a reactor (e.g., downstream of the FT reactor) can be used to achieve such hydrogen concentrations. Representative auxiliary sources of hydrogen include purified hydrogen (e.g., by PSA or membrane separation) or impure hydrogen (e.g., syngas). Representative sources of hydrogen replenishment may be one or more gaseous feedstock mixture components. For example, among these components, although usually supplied to the reforming stage or the RWGS stage, instead, they are directly supplied to the polishing or cracking reactor and thus are portions that do not actually contribute to the gaseous mixture. For example, one or more gaseous feedstock mixture components include one or more fresh gaseous feedstock mixture components and / or one or more recycled gaseous feedstock mixture components described herein, and a portion of the one or more fresh gaseous feedstock mixture components can be directly supplied to the polishing reactor.In more specific embodiments, one or more fresh gaseous feed mixture components, a portion of which is fed directly to at least one polishing reactor, are fresh make-up H containing hydrogen in an amount of at least about 50 mol%, at least about 80 mol%, at least about 95 mol%. 2 This is a feedstock. Some or all of this hydrogen can more specifically be electrolytic hydrogen, fossil hydrogen by CCS, biogasified hydrogen, or methane pyrolysis hydrogen.

[0091] Suitable cracking / hydrocracking and / or isomerization / hydroisomerization reactions can similarly or alternatively occur in the cracking or polishing feedstock and / or FT synthesis effluent in the presence of steam (H 2 O) that may be present as a product of the RWGS reaction occurring, for example, in an upstream reforming stage or RWGS stage. For example, an auxiliary steam source can be added to the cracking reactor or polishing reactor, or upstream of such a reactor (e.g., downstream of the FT reactor). According to some embodiments, the steam is at least about 5 mol% (e.g., about 5 mol% to about 45 mol%), at least about 10 mol% (e.g., about 10 mol% to about 40 mol%), or at least about 15 mol% (e.g., about 15 mol% to about 35 mol%) in concentration, regardless of the introduction of a supplementary source of steam other than the steam present in the steam produced in the reforming stage or RWGS stage and / or the synthesis gas intermediate, and can be present in the cracking or polishing feedstock and / or FT synthesis effluent.

[0092] Representative cracking catalysts or polishing catalysts contain at least one cracking active metal on a solid support. The phrase "on a solid support" is intended to include catalysts in which the active metal(s) is / are on the support surface and / or within the porous internal structure of the support. Representative cracking active metals or polishing active metals can be selected from Groups 12 - 14 of the periodic table, such as Group 13 or Group 14 of the periodic table. In particular, an effective metal for cracking and polishing is gallium. The at least one cracking active metal can be present in an amount, for example, of about 0.1 wt% to about 10 wt%, about 0.5 wt% to about 8 wt%, or about 1 wt% to about 5 wt% based on the weight of the cracking catalyst or polishing catalyst. When combinations of cracking active metals are used, such as combinations of metals selected from Groups 12 - 14 of the periodic table, such metals can be present in a total amount within these ranges. Generally, the cracking catalyst or polishing catalyst may not contain metals other than the above cracking active metal(s) or polishing active metal(s) in an amount exceeding about 1 wt%, or exceeding about 0.5 wt%, or in total amount on the support (e.g., metals other than those from Groups 12 - 14 of the periodic table, metals other than those from Group 13 or Group 14 of the periodic table, or metals other than gallium are not contained in this amount or total amount). Preferably, the cracking catalyst or polishing catalyst does not contain metals other than the above cracking active metal(s) or polishing active metal(s) on the support (e.g., does not contain metals other than those from Groups 12 - 14 of the periodic table, does not contain metals other than those from Group 13 or Group 14 of the periodic table, or does not contain metals other than gallium).

[0093] To promote cracking activity, the solid support of the cracking catalyst or polishing catalyst can more specifically be a solid acidic support. The acidity of the support, i.e., as described above, NH 3-TPD can be used to determine by temperature-programmed desorption (TPD) of a certain amount of ammonia. This analysis is specifically carried out on an ammonia-saturated sample of the support at a temperature from 275 °C (527 °F) to 500 °C (932 °F), which exceeds the temperature at which ammonia is physically adsorbed. Thus, the amount of acid sites (in millimoles of acid sites per gram of support (mmol / g)) corresponds to the number of millimoles of ammonia desorbed per gram of support in this temperature range. Representative solid supports include zeolite-based or non-zeolite-based molecular sieves, NH 3 -Measured by TPD, it has at least about 15 mmol / g (e.g., about 15 to about 75 mmol / g) of acid sites, or at least about 25 mmol / g (e.g., about 25 to about 65 mmol / g) of acid sites. In the case of zeolite molecular sieves, the acidity is a function of the molar framework ratio of silica to alumina (SiO 2 / Al 2 O 3 ). In embodiments where the solid support includes a zeolite molecular sieve (zeolite), the molar framework ratio of silica to alumina can be less than about 60 (e.g., about 1 to about 60), or less than about 40. (e.g., about 5 to about 40). Certain solid supports can include one or more zeolite molecular sieves (zeolites) having a structure type selected from the group consisting of FAU, fer, mel, mtw, MWW, mor, BEA, ltl, MFI, ta, emt, eri, maz, mei, and ton, preferably selected from one or more of FAU, fer, MWW, MOR, BEA, ltl, and MFI. The structures of zeolites having these and other structure types are described in Meier, W. M, et al., Atlas of Zeolite Structure Types, 4 th Ed., Elsevier: Boston (1996), and further references are also provided. Specific examples include zeolite Y (FAU structure), zeolite X (FAU structure), MCM-22 (MWW structure), ZSM-5 (MFI structure), etc., and ZSM-5 is representative.

[0094] As solid carriers other than zeolite-based and non-zeolite-based molecular sieves, one or more metal oxides such as silica, alumina, titania, zirconia, magnesium oxide, calcium oxide, strontium oxide are included. In a representative embodiment, the solid carrier comprises (i) a single type of zeolite molecular sieve, (ii) a single type of non-zeolite molecular sieve, or (iii) a single type of metal oxide, where (i), (ii), or (iii) is present in an amount exceeding about 75% by weight (e.g., about 75% to about 99.9% by weight), or an amount exceeding about 90% by weight (e.g., about 90% to about 99% by weight), based on the weight of the cracking catalyst or polishing catalyst. Other components of the carrier, such as binders and other additives, may be present in trace amounts, such as amounts less than about 10% by weight (e.g., about 1% to about 10% by weight) or total amounts, based on the weight of the cracking catalyst or polishing catalyst.

[0095] An exemplary cracking catalyst contains gallium as a cracking active metal, which is present in the above amounts (e.g., about 0.5% to about 8% by weight, such as about 1% to about 5% by weight, based on the weight of the cracking catalyst) on a carrier containing ZSM-5 or perhaps consisting essentially of ZSM-5. The typical molar framework ratio of silica to alumina of ZSM-5 is described above.

[0096] The cracking catalysts or polishing catalysts described herein and the reaction conditions associated therewith are generally for normal C 20 + from hydrocarbons to C 1 ~C 19It may be suitable to achieve a conversion of at least about 50% (e.g., about 50% to about 100%), at least about 70% (e.g., about 70% to about 98% or about 70% to about 100%), or at least about 90% (e.g., about 90% to about 95% or about 90% to about 100%) to hydrocarbons. When using the cracking catalyst contained in the FT reactor for in-situ cracking and both the polishing catalysts contained in another polishing reactor downstream of the FT reactor, these conversion levels may represent the conversion obtained from the combination of the cracking catalyst and the polishing catalyst (e.g., C remaining in the polishing effluent 20 + determined based on the amount of hydrocarbons). C 20 + Hydrocarbon conversion is important for improving the yield of hydrocarbons and thus the overall yield of liquid hydrocarbon products compared to operating the FT synthesis stage without using in-situ cracking or another polishing reactor. Preferably, in the case of a separate cracking or polishing reactor (regardless of whether it is used in combination with in-situ cracking in the FT reactor), at least about 40% (e.g., about 40% to about 100%), at least about 55% (e.g., about 55% to about 98% or about 55% to about 100%), or at least about 65% (e.g., about 65% to about 97% or about 65% to about 100%) of the C 4 ~C 19 in the FT synthesis effluent is converted to C 20 + hydrocarbons. That is, the yields of these hydrocarbons obtained from the normal C 4 ~C 19 hydrocarbon conversion in another cracking reactor or polishing reactor are within these ranges. Preferably, the polishing effluent (the product of the polishing reactor) is a hydrocarbon that is solid at room temperature (e.g., normal C 20 + hydrocarbons). 20 +contains less than about 10 wt%, or less than about 5 wt%, of hydrocarbons. Advantageously, the FT synthesis stage utilizing in-situ cracking and / or another polishing reactor provides FT synthesis effluents and / or polishing effluents that are either completely or substantially free of residual wax or have a sufficiently low hydrocarbon content such that the hydrocarbons are solids at room temperature, such that these hydrocarbons are soluble in the recovered C obtained as the output of the process 4 + remain soluble in hydrocarbons (e.g., the recovered diesel boiling range hydrocarbon fraction).

[0097] Accordingly, embodiments of the present invention relate to using a cracking or polishing reactor after the FT reactor to improve the overall selectivity and yield to the desired product and / or reduce the overall selectivity and yield to the undesired product compared to the FT synthesis stage without cracking or polishing, i.e., compared to a baseline FT synthesis stage without in-situ cracking or another polishing reactor. For example, in a representative embodiment, the selectivity and / or yield to C 4 ~C 19 hydrocarbons can increase by at least about 15% (e.g., from about 15% to about 70%), at least about 30% (e.g., from about 30% to about 65%), or at least about 45% (e.g., from about 45% to about 60%) in the FT synthesis stage using in-situ cracking and / or another polishing reactor compared to the baseline FT synthesis stage. C 4 ~C 19 The selectivity to hydrocarbons is based on the proportion of carbon in the CO converted by FT, such that these hydrocarbons are produced. C 4 ~C 19 The yield of hydrocarbons is based on the proportion of carbon in the CO introduced into the FT synthesis stage (e.g., CO introduced with the FT feedstock, whether converted or unconverted), such that these hydrocarbons are produced. C 4 ~C 19These increases in selectivity and / or yield to hydrocarbons can be achieved without causing a large difference between the CO conversion obtained in the baseline FT synthesis stage and the CO conversion obtained in the FT synthesis stage using in-situ cracking and / or another polishing reactor as a result of incorporating in-situ cracking and / or another polishing reactor. For example, the CO conversion values obtained in both cases can be within the range described above with respect to the performance criteria of the FT synthesis stage. That is, the use of in-situ cracking and / or another polishing reactor generally does not significantly affect the CO conversion obtained in the FT synthesis stage, and thus the CO conversion achieved in both the baseline FT synthesis stage and the FT synthesis stage using in-situ cracking and / or another polishing reactor can be the same or substantially the same. In a representative embodiment, C 4 ~C 19 The per-pass selectivity and / or yield to hydrocarbons can be at least about 45% (e.g., about 45% to about 85%), at least about 50% (e.g., about 50% to about 80%), or at least about 55% (e.g., about 55% to about 75%) in the FT synthesis stage using in-situ cracking and / or another polishing reactor.

[0098] As noted above, the conversion level in the cracking or polishing reactor may be based on the "per-pass" conversion achieved by passing the reactor once, or may be based on the overall conversion achieved by recycling a portion of the polishing effluent back to the cracking or polishing reactor as described above with respect to FT synthesis. Normal C 20 + The desired conversion of hydrocarbons can be achieved by adjusting the cracking or polishing reaction conditions (e.g., cracking reaction temperature and / or pressure) described above and / or by adjusting the weight hourly space velocity (WHSV) defined above. The cracking or polishing reaction conditions generally range from about 0.05 hr -1 ~about 35 hr -1 Typically from about 0.1 hr -1 ~about 20 hr -1, often about 0.5 hr -1 to about 10 hr -1 A weight hourly space velocity (WHSV) may be included. The cracking or polishing reaction conditions may optionally include returning a recycled portion of the polishing effluent discharged from the cracking or polishing reactor to the FT synthesis effluent to combine with the polishing feedstock, or returning it to the polishing reactor itself. By the recycling operation, the "per pass" conversion rate when passing through the cracking or polishing reactor is kept relatively low, and the overall conversion rate is increased by recycling. However, preferably, the cracking or polishing reaction conditions include little or no recycling of the polishing effluent. For example, the cracking or polishing reaction conditions may include the weight ratio of the recycled polishing effluent to the cracking feedstock (i.e., the "recycle ratio"), and the recycled polishing effluent and the FT synthesis effluent are combined to provide a composite feedstock to the cracking or polishing reactor corresponding to the above recycle ratio for FT synthesis. Preferably, the recycle ratio can be 0, which means that no recycling of the polishing effluent is used, so the per pass conversion rate is equal to the overall conversion rate. Advantageously, since there is no recycling of the polishing effluent, utility costs are saved and the overall design of the integrated process is simplified.

[0099] Accordingly, embodiments of the present invention relate to a process for converting normal C 4 ~C 19 hydrocarbons in a feedstock containing hydrocarbons, and may include all or part of the above FT products. The feedstock containing normal C 20 + hydrocarbons may contain C 20 + hydrocarbons in an amount of at least about 40 wt% (e.g., about 40 wt% to about 90 wt%) or at least about 50 wt% (e.g., about 50 wt% to about 80 wt%), based on the weight of the total hydrocarbons or based on the weight of the feedstock. The feedstock may contain C 4 ~C 19 hydrocarbons. The feedstock may contain H 2 and / or H 2O (e.g., the amounts described above with respect to the FT synthesis effluent), CO, and / or CO 2 may further be included. This process involves contacting the feedstock with a cracking catalyst containing an active metal (e.g., gallium) selected from Groups 12-14 of the periodic table (e.g., gallium) on a zeolite molecular sieve support (e.g., ZSM-5), as described above, to convert normal C 20 + hydrocarbons at a conversion level and also C 4 -C 19 hydrocarbons in terms of yield and selectivity, as described herein.

[0100] As described above, the step of converting a synthesis gas intermediate to a liquid hydrocarbon product may involve the use of an FT reactor in the case of a step combining FT synthesis and cracking, in which in-situ or integrated cracking is carried out. Examples of such reactors include a single vessel containing a fixed bed of a cracking catalyst downstream (e.g., immediately downstream) of a fixed bed of an FT catalyst, or a single vessel containing a single fixed bed in which two catalysts are dispersed or mixed in a suitable weight ratio. Alternatively, a fluidized bed of the two catalysts described herein can also be used. The advantage of the operation of a fluidized bed reactor is that heat and mass transfer are increased, and as a result, the FT and cracking reaction conditions become more uniform overall. In an alternative embodiment, the two catalysts can also be used in a slurry bed (e.g., slurry bubble) configuration, or these catalysts can be incorporated into tubes in a multi-tube configuration. A fluidized bed reactor can also be used. All of these reactor configurations, such as slurry reactors, multitubular reactors, fluidized bed reactors, etc., can generally be characteristic of an FT reactor, regardless of whether the reactor contains a catalyst or a catalytic functional component for carrying out in-situ or integrated cracking. Thus, the forms of the FT catalyst and cracking catalyst described herein are suitable for these various reactor configurations and include spherical shapes having a relatively small average diameter, such as from about 100 μm to about 1 mm, or from about 250 μm to about 750 μm, and other forms as described above (e.g., cylindrical). Generally, the combination of FT synthesis and in-situ or integrated cracking refers to carrying out both of these reactions, at least to some extent, using at least one FT reactor in the FT synthesis stage. Representative conditions in such a reactor include any of the above-described FT reaction conditions or cracking reaction conditions, e.g., any of the ranges of temperature, pressure, and WHSV given for these conditions.

[0101] Further embodiments for performing the FT synthesis in combination with in-situ or integrated cracking include the use of a single catalyst composition, i.e., a bifunctional catalyst comprising both an FT functional component and a cracking functional component, where these components individually correspond to the FT catalyst and the cracking catalyst as described above. For example, in the case of the cracking functional component, this may include one or more cracking active metals selected from Groups 12 to 14 of the periodic table, and the one or more cracking active metals may be deposited on a solid acidic support, which may include a zeolite molecular sieve having a silica to alumina molar framework ratio of less than about 50. Similarly, in the case of the FT functional component, in certain embodiments, this component corresponds to the FT catalyst described above.

[0102] When combined in a single catalyst composition, the functional components of the bifunctional catalyst can be present in equal or substantially equal weight ratios. For example, (i) the FT functional component and (ii) the cracking functional component may be present in the bifunctional catalyst in a weight ratio of (i):(ii) of about 1:1. However, generally, this weight ratio may vary. For example, the weight ratio of (i):(ii) can be from about 10:1 to about 1:10, such as from about 5:1 to about 1:5, or from about 3:1 to about 1:3. Thus, a typical bifunctional catalyst can include (i) an FT functional component that includes one or both of (a) one or more FT active metals and (b) a solid support for the FT catalyst (e.g., including one or more metal oxides), as described above, and (ii) a cracking functional component that includes one or both of (a) one or more cracking active metals and (b) a solid support for the cracking catalyst (e.g., a solid acidic support), as described above. From the above description, it can be understood that (a) and (b) of (i), and (a) and (b) of (ii), including the weight ratios that can combine (i) and (ii), can be present in the bifunctional catalyst as a whole in amounts less than the amounts present in their respective FT catalysts and cracking catalysts, as described above. For example, in the case of the FT functional component of the bifunctional catalyst, such a whole bifunctional catalyst can include a transition metal(s) (i.e., one or more FT active metals such as Co described above) in a lesser amount, e.g., at least about 3 wt% (e.g., from about 3 wt% to about 30 wt%), typically at least about 5 wt% (e.g., from about 5 wt% to about 25 wt%), based on the weight of the bifunctional catalyst. Similarly, in the case of the cracking functional component of the bifunctional catalyst, such a whole bifunctional catalyst can include a metal(s) of Groups 12 - 14 of the periodic table (i.e., one or more cracking active metals such as those described above) in a lesser amount, such as from about 0.03 wt% to about 2 wt%, or from about 0.1 wt% to about 1 wt%, based on the weight of the bifunctional catalyst.

[0103] Thus, by combining FT synthesis and cracking, H 2The step of converting a syngas intermediate comprising a H / CO mixture to a liquid hydrocarbon product can be carried out in-situ cracking or in an integrated FT reactor. More specifically, this step may include contacting the syngas intermediate (or H 2 / CO mixture) with a bifunctional catalyst having an FT functional component and a cracking functional component. Once-through and recycle operation / Exemplary embodiments

[0104] The process for producing the liquid hydrocarbon products described herein can be carried out in a once-through operation (so configured), whereby a gaseous feed mixture is input and the liquid hydrocarbon product (optionally, after separation from the FT synthesis effluent or the polishing effluent as described above) is withdrawn without recycling any portion of the material obtained in the first or second reaction stage. In the case of a once-through operation, the "gaseous feed mixture" and the "fresh make-up feed" (which may represent a combination of multiple fresh gas feed components) are usually equivalent, and the conversion level and product yield obtained from the process represent the conversion level and product yield when passing through the reforming and / or RWGS and FT synthesis stages once. As described above, certain aspects of the present invention relate to a liquid hydrocarbon production process that enables effective management / conversion of CO present in the gaseous feed mixture or fresh make-up feed, which can be improved by a recycling operation. In particular, recycling CO (e.g., present in (i) H 2 and CO 2 (e.g., (i) H 2 and CO 2 or (ii) a hydrogen source and a CO 2 -rich fraction separable from the FT synthesis effluent or the polishing effluent) back to the first stage (e.g., the reforming stage, e.g., the reforming / RWGS stage) and / or back to the second FT synthesis stage for further reaction can promote complete or substantially complete overall conversion. For example, in a representative embodiment where a recycling operation is used as described herein, CO present in the fresh make-up feed (having a composition as described above with respect to the "gaseous feed mixture" and representing a combination of two or more fresh gaseous feed components) 2The overall conversion rate can be at least about 90%, at least about 95%, or at least about 99%, and the deviation from the complete or 100% conversion rate is substantially or at least in part due to the loss of CO 2 in the purge exiting the gaseous recycle loop used to control the accumulation of unwanted impurities within this loop. That is, according to some embodiments, the CO 2 introduced into the process with fresh make-up feedstock can be recycled until it is substantially depleted. As noted above, with respect to the fractions that can be separated and / or recovered from the FT synthesis effluent, (i) H 2 and CO 2 rich fractions or (ii) hydrogen source and CO 2 rich fractions are recycled, for example, to the first stage (e.g., reforming stage, e.g., reforming / RWGS stage) and / or the second stage of the FT synthesis stage, and the important advantages described herein are obtained. In some cases, only the recycled portion of fraction (i) or (ii) is recycled to the first stage, or a portion of the recycled portion of fraction (i) or (ii) is recycled to the first and second stages. As further described herein, the conversion rate and product yield can be further adjusted by recycling at least a portion of the C 4 + hydrocarbons present in the liquid hydrocarbon product, for example, by recycling all or a portion of a separated fraction rich in naphtha boiling range hydrocarbons or another type of hydrocarbon. The recycling in this case is typically carried out up to the first stage, where the recycled hydrocarbons can be reformed to increase the yield of synthesis gas intermediates containing an H 2 / CO mixture.

[0105] An exemplary embodiment of Process 1 for producing liquid hydrocarbon products and utilizing recycle is shown in FIG. 1. As shown, a gaseous feed mixture 6 is provided to a reforming or RWGS stage 100, which may include one or more reforming / RWGS reactors for contacting the gaseous feed mixture 6 with a reforming / RWGS catalyst and reacting under reforming / RWGS conditions as described herein. The reaction occurring in the reforming or RWGS stage 100 produces a syngas intermediate 8, which can be subjected to one or more intervening operations described herein. For example, water, such as in the form of condensed liquid water 9, can be separated from the syngas intermediate 8 to provide an FT feed 10. Optionally, or in combination with the removal of this condensed liquid water 9, a fraction 14 of the FT synthesis effluent 12 (which can be a fraction rich in (i) H 2 and CO 2 or (ii) a hydrogen source and CO 2 as described herein) can be added to the syngas intermediate 8 to provide the FT feed 10.

[0106] The fraction 14 of the FT synthesis effluent 12 is more specifically a fraction rich in (i) H 2 and CO 2 compared to the liquid hydrocarbon product 16 and the FT synthesis effluent 12. This fraction enriched in (i) can also be referred to as an H 2 / CO 2 enriched fraction and is generally a gaseous fraction (e.g., a fraction that is substantially completely or completely in the gas phase) and can be used to form a gaseous recycle loop of the process. This fraction can contain H 2 and CO 2 in a total amount of at least about 20 mol% (e.g., about 20 mol% to about 95 mol%), at least about 40 mol% (e.g., about 40 mol% to about 90 mol%), or at least about 60 mol% (e.g., about 60 mol% to about 85 mol%). The remainder of this fraction is CO, CH 4 , C 2 H 6 , C 3 H 8 , and / or H 2It may contain O. For example, the balance may include all, or substantially all, of these components, or two or more of these components. Fraction 14 of the FT synthesis effluent 12 is, more specifically, compared to the liquid hydrocarbon product 16 and the FT synthesis effluent 12, (ii) a fraction rich in a hydrogen source and CO 2 and may be a rich fraction. This fraction enriched in (ii) is also called a fraction rich in hydrocarbons / CO 2 (or a fraction rich in methane / CO 2 ) and is usually a gaseous fraction (e.g., a fraction that is substantially completely or completely in the gas phase) and can be used to form the gaseous recycle loop of the process. This fraction may contain one or more of hydrocarbons (e.g., CH 4 , C 2 H 6 , C 3 H 8 ) in a total amount of at least about 20 mol% (e.g., about 20 mol% to about 95 mol%), at least about 40 mol% (e.g., about 40 mol% to about 90 mol%), or at least about 60 mol% (e.g., about 60 mol% to about 85 mol%). The remainder of this fraction may contain H 2 , CO, and / or H 2 O. For example, the balance may include all, or substantially all, of these components, or two or more of these components. Thus, fraction 14 can be regarded as the "light fraction" fraction of the FT synthesis effluent 12 (Figure 1) or the polishing effluent 13 (Figure 2), contains hydrocarbons in the gas phase at room temperature (e.g., CH 4 , C 2 H 6 , and / or C 3 H 8 ), is produced as a light hydrocarbon by-product of the FT synthesis, and / or is introduced as a hydrogen source into the fresh make-up feedstock.

[0107] Furthermore, according to the embodiment shown in Figure 1, a second portion 4b of fraction 14 of the FT synthesis effluent 12, which may be a fraction rich in (i) or (ii), can be added (or recycled) to the syngas intermediate 8, and as a result, the composition of the FT feedstock 10 relative to the composition of the syngas intermediate 8, more specifically the H of the FT feedstock 10 2: The CO molar ratio can vary. Whether or not an intervening operation is performed, FT feedstock 10 (which will be the same as synthesis gas intermediate 8 in the absence of an intervening operation) or a portion thereof is provided to the FT synthesis stage 200, which may include one or more FT reactors for contacting the FT feedstock 10 (or synthesis gas intermediate 8) with an FT synthesis catalyst system and reacting it under the FT reaction conditions described herein. The reaction occurring in the FT synthesis stage 200 produces an FT synthesis effluent 12 that can be obtained directly from the FT synthesis stage 200. All or a portion of the FT synthesis effluent 12 can be provided to a separation stage 300 for separating the various fractions as described above, optionally after further intervening operations such as cooling by a cooler 250. According to the specific embodiment shown in FIG. 1, the separated fractions can include a fraction 14 rich in (A)(i) or (ii) (among one or more other fractions, for example), and (B) CC 4 +A liquid hydrocarbon product 16 is included or may be composed of hydrocarbons containing hydrocarbons and having any of the more specific characteristics regarding its composition as described above. Depending on the specific operations performed in the separation stage 300, the liquid hydrocarbon product can be obtained in the form of separated fractions 16b, 16c, such as a fraction 16b rich in hydrocarbons in the jet fuel boiling range and a fraction 16c rich in hydrocarbons in the diesel boiling range. Alternatively, the liquid hydrocarbon product 16 can be separated downstream of the separation stage, for example, in another liquid product separation stage 400, where a fractionating device (e.g., a distillation column) can be used to separate a fraction 16b rich in hydrocarbons in the jet fuel boiling range and a fraction 16c rich in hydrocarbons in the diesel boiling range. The separated fractions can be composed of or essentially composed of these respective types of hydrocarbons in addition to containing these respective types of hydrocarbons in abundance. For example, the separated fraction 16b can be composed of or essentially composed of hydrocarbons in the jet fuel boiling range, and the separated fraction 16c can be composed of or essentially composed of hydrocarbons in the diesel boiling range. As a further example of the separated fractions, the separated fraction 16a shown in FIG. 2 can be included, which is rich in hydrocarbons in the naphtha boiling range or more specifically can be composed of or essentially composed of hydrocarbons in the naphtha boiling range. According to the embodiment shown in FIG. 2, at least a portion of this separated fraction 16a is recycled to the reforming stage or the RWGS stage 100, but in other embodiments, such separated fractions are completely recovered as the output of the process and thereby can contribute to the yield of hydrocarbons in the naphtha boiling range.

[0108] Total CO 2 To improve conversion and management, at least a portion of the fraction 14 enriched in (i) or (ii) can be recycled to upstream operations or stages of a process including the reforming stage or the RWGS stage 100 and / or the FT synthesis stage 200. Typically, for example, the recycled portion 4 of the fraction 14 (e.g., the fraction enriched in (i) as described above, which is H 2 / CO 2(ii)-rich fraction as above (which is also called the hydrocarbon / CO 2 The N-rich fraction (also called the N-rich fraction) is a fraction of undesirable impurities in the gas recycle loop, particularly N that may be present in the fresh feedstock 2. 2 The fraction 14 is obtained after removing the purge 20, which serves to limit the accumulation of non-condensable impurities such as H. 2 / CO 2 The CO-rich fraction 14 may be advantageously utilized as the recycled portion 4 to improve the overall process performance in various ways. For example, the recycled portion 4 may be recycled to either or both of steps 100, 200 to reduce the CO 2 Conversion rates can be increased (e.g., “per pass” or single pass CO yields based on either stage operating alone or both stages operating together). 2 Alternatively, or in combination, the CO present in fraction 14 or in its recycled portion 4 2 When introduced into one or both of stages 100, 200, particularly into the FT synthesis stage 200, it reduces the amount of pure CO in that stage (e.g., by the water gas shift reaction). 2 Advantageously, the production of FT synthesis gas can be suppressed or reduced. According to the particular embodiment shown in Fig. 1, a first portion 4a of the recycle portion 4 is recycled to the reforming or RWGS stage 100 (e.g., by combining with fresh make-up feed 2), optionally after compression by compressor 360 if stage 100 requires a feed gas at a higher pressure than that provided by the recycle portion 4, and / or a second portion 4b is recycled to the FT synthesis stage 200 (e.g., by combining with synthesis gas intermediate 8 or FT feed 10), after compression by compressor 350. In general, portions 4a, 4b, as well as purge 20 and recycle portion 4 have the same composition as fraction 14, although in some embodiments this may not necessarily be the case (e.g., if purge 20 is provided as a result of a separation that enriches this stream with certain undesirable impurities).

[0109] From the perspective of recycling fraction 14 or any part(s) thereof to a specific stage of the process, selecting a specific recycling configuration may depend at least in part on the above considerations regarding the increase in the overall CO 2 conversion rate and / or the suppression of CO 2 generation at a specific stage(s). Those skilled in the art with knowledge of the present disclosure will understand that these and other considerations are applicable to specific processes within the scope of the invention. As is apparent from the above description, all of the recycling portion 4 and its parts 4a, 4b that can be sent to different locations constitute, or alternatively constitute, "a part of the fraction" 14, which fraction is rich in (i) or (ii) as described throughout the present disclosure. Thus, for example, the gaseous feed mixture 6 can be provided to the reforming stage or the RWGS stage 100 as a combination of fresh make-up feed 2 and a part of fraction 14 (e.g., all of the recycling portion 4 or part 4a of this portion).

[0110] According to a particular embodiment, the fresh make-up feed 2 can contain biogas or be essentially composed of biogas. In such an embodiment, the gaseous feed mixture 6 can contain biogas present as fresh make-up feed or fresh gaseous mixture feed mixture components 2a, 2b (Figure 2). According to other particular embodiments, the fresh make-up feed 2 can contain CO removed from the atmosphere (e.g., via direct air capture) or captured from the exhaust stream of biomass combustion, and further can contain electrolytic H 2 (e.g., generated using renewable electricity), fossil hydrogen by CCS, biogas hydrogen, or methane pyrolysis hydrogen. According to still other particular embodiments, the fresh make-up feed 2 can contain the effluent from the gasification of biomass, such as CO 2 (e.g., generated using renewable electricity), fossil hydrogen by CCS, biogas hydrogen, or methane pyrolysis hydrogen. According to still other particular embodiments, the fresh make-up feed 2 can contain the effluent from the gasification of biomass, such as CO 2 , H 2 , and CO, and optionally CH 4 , and further can contain electrolytic H 2Makeup HH that is, for example, fossil hydrogen, biogasified hydrogen, or methane pyrolysis hydrogen produced using renewable electricity 2 may be included. According to still other specific embodiments, the fresh makeup feedstock 2 may include, for example, residual gas containing CO 2 , H 2 , CH 4 , and CO.

[0111] A further exemplary embodiment of Process 1 for producing liquid hydrocarbon products is shown in FIG. 2. Comparing FIGS. 1 and 2, various aspects related to the processes described herein become apparent, such as the ability to input the recycle stream directly into the reactor rather than combining the recycle stream with other process streams before feeding them to these reactors. Thus, for example, the gaseous feedstock mixture 6 may result from a combination of the first portion 4a of the fractionation 14 and the fresh makeup feedstock 2 as shown in FIG. 1, or according to FIG. 2, from a combination of fresh gaseous feedstock mixture components, namely fresh makeup CO 2 and / or CH 4 -containing feedstock 2a and fresh makeup H 2 -containing feedstock 2b, and may occur in situ within the reactor of the reforming or RWGS stage 100, where the feedstocks 2a and 2b may, in certain embodiments, be composed of a single combined feed. Similarly, the FT feedstock 10 shown in FIG. 1 is produced in situ within the FT reactor 200a shown in FIG. 2 from a combination of the second portion 4b of the fractionation 14 and the syngas intermediate 8. FIG. 2 further shows options for compression, such as using the syngas intermediate / FT feedstock compressor 125 in addition to the recycle gas compressors 350 and 360, where the compressor 125 is used to obtain the appropriate pressure within the FT reactor 200a to match the FT reaction conditions described herein. FIG. 2 further shows options for water removal, such as using the liquid product separation stage 400 for the purpose of removing condensed liquid water 9, which is optionally used in combination with water removal from the syngas intermediate 8 as shown in FIG. 1.

[0112] As further shown in Figure 2, the FT synthesis stage 200 may, according to certain embodiments, include both an FT reactor 200a and a downstream polishing reactor 200b. Generally, in some embodiments consistent with this figure, the FT synthesis stage may include at least one FT reactor 200a containing a mixture of an FT catalyst and a cracking catalyst (such as a catalyst having the composition described herein). The FT synthesis stage may further include at least one polishing reactor 200b downstream of at least one FT reactor 200a, such as when the FT reactor 200a supplies the FT synthesis effluent 12, and the process further includes supplying the FT synthesis effluent 12 to the polishing reactor 200b. The polishing reactor may contain one or more polishing catalysts, but the polishing reactor 200b contains no or substantially no FT catalyst. This FT catalyst may be completely or substantially absent from the polishing reactor and may refer to a specific FT catalyst contained in the FT reactor 200a or to other FT catalysts described herein. The polishing catalyst may have the same composition and / or the same form as the cracking catalyst contained in the FT reactor, but these compositions and / or forms may differ depending on the operating processes of the FT reactor and the polishing reactor. Generally, in other embodiments consistent with Figure 2, the FT synthesis stage may include at least one FT reactor containing a bifunctional catalyst having an FT functional component and a cracking functional component (such as a functional component having the composition described herein). The FT synthesis stage may further include at least one polishing reactor 200b downstream of at least one FT reactor 200a, such as when the FT reactor 200a supplies the FT synthesis effluent 12, and the process further includes supplying the FT synthesis effluent 12 to the polishing reactor 200b. The polishing reactor may contain a polishing catalyst, but the polishing catalyst contains substantially no FT functional component. This FT functional component may be completely or substantially absent from the polishing catalyst and may refer to either a specific FT functional component of the catalyst contained in the FT reactor 200a or to other FT functional components described herein. The polishing catalyst may have the same composition as the cracking functional component corresponding to the bifunctional catalyst contained in the FT reactor, excluding the FT functional component.Alternatively, depending on the operating processes of the FT reactor and the polishing reactor, the compositions of the polishing catalyst and the cracking functional component may be different.

[0113] Generally, in some embodiments consistent with FIG. 2, in the FT synthesis stage, the step of converting the synthesis gas intermediate 8 containing the H 2 / CO mixture may include contacting this intermediate or this mixture with a mixture of an FT catalyst and a cracking catalyst (e.g., contained in the FT reactor 200a) to provide an FT synthesis effluent 12. H 2 The conversion of the synthesis gas intermediate 8 containing the H / CO mixture may further include contacting the FT synthesis effluent 12 with a polishing catalyst (e.g., contained in the polishing reactor 200b), for example, to provide a polishing effluent 13 in a state where the FT catalyst is substantially absent. Generally, in other embodiments consistent with FIG. 2, in the FT synthesis stage, the step of converting the synthesis gas intermediate 8 containing the H 2 / CO mixture may include contacting this intermediate or this mixture with a bifunctional catalyst having an FT functional component and a cracking functional component (e.g., contained in the FT reactor 200a) to provide an FT synthesis effluent 12. H 2 The conversion of the synthesis gas intermediate 8 containing the H / CO mixture may further include contacting the FT synthesis effluent 12 with a polishing catalyst (e.g., contained in the polishing reactor 200b) where, for example, the FT functional component is substantially absent to provide a polishing effluent 13. In any of the embodiments, the cracking catalyst or the cracking functional component may optionally have any of the optional compositions described herein. For example, such a catalyst or functional component may include one or more cracking active metals selected from Groups 12 to 14 of the periodic table.

[0114] From the embodiments shown in FIG. 2, it was found that the gaseous raw material mixture may include, as components, a fresh gaseous raw material mixture component and a recycled gaseous raw material mixture component as inputs to the process. For example, with respect to the fresh make-up feed 2 shown in FIG. 1, the fresh gaseous raw material mixture component shown in FIG. 2, i.e., the fresh make-up CO described herein 2 and / or CH4 Containing feedstock 2a and fresh make-up H 2 It can be provided as a combination with feedstock 2b. Fresh make-up H 2 All or part of feedstock 2b, for example the first part 25a, can be added directly to the reforming stage or RWGS stage 100 (e.g., the reforming / RWGS reactor used in this stage), and thus can become a component of the gaseous feedstock mixture. Fresh make-up H 2 All or part of feedstock 2b (e.g., the second part 25b) can be added directly to the polishing reactor 200b as a co-feed for the polishing reactor. Thus, in the embodiment consistent with FIG. 2, in the FT synthesis stage, the polishing catalyst (e.g., contained in the polishing reactor 200b) has a fresh make-up H with the composition described herein 2 In addition to feedstock 2b or a part 25b thereof, it can be contacted with the FT synthesis effluent 12. This feedstock can contain, for example, H obtained from the electrolysis of water 2 , fossil hydrogen by CCS, biogas hydrogen, or methane pyrolysis hydrogen. Regardless of the source, H 2 is fresh make-up H 2 is present in feedstock 2b, and as a result, at least about 50 mol% of H is present in parts 25a, 25b having the same composition 2 in an amount.

[0115] Thus, the gaseous feedstock mixture includes the first part 25a of feedstock 2b containing fresh make-up H, i.e., the part directly supplied to the reforming stage or RWGS stage 100 (e.g., the reforming / RWGS reactor used in this stage), and provides an input to the process. A typical process may further include directly supplying the second part 25b of feedstock 2b containing fresh make-up H to the FT synthesis stage 200, or, in a preferred embodiment, directly supplying it to the polishing reactor 200b used in this stage. In this regard, aspects of the present invention, as described herein, have a fresh make-up H 2 2 2 ​​It is related to the discovery that directly supplying hydrogen to the polishing reactor 200b using a convenient source of hydrogen present in feedstock 2b is advantageous in promoting hydrogenation processes (e.g., hydrocracking and hydroisomerization) reactions in this reactor. Importantly, this portion 25b of the feedstock is usually fed to the reforming or RWGS stage 100 together with portion 25a, but when it is directly introduced into the polishing reactor 200b, the CO partial pressure in this reactor decreases, thereby improving the performance of the polishing catalyst contained in this reactor, and C 20 + hydrocarbons are converted and / or the stability of this catalyst is improved (i.e., the catalyst deactivation rate decreases). As described above, the portion 25b directly supplied to the polishing reactor 200b is more specifically the second portion, and the first portion 25a can be directly supplied to the reforming or RWGS stage 100 (e.g., the reforming / RWGS reactor used in this stage).

[0116] Another specific aspect of the present invention is that the flow rates of the fresh stream and recycle stream in the process described herein can be advantageously adjusted based on the CO concentration (CO mol%) or CO partial pressure, and H 2 :CO molar ratio at various points (measurement points or control points) in the FT synthesis stage (e.g., control of the CO mol% or CO partial pressure in the polishing reactor 200b, and / or H 2 :CO molar ratio control in the FT reactor 200a). In a specific exemplary embodiment regarding CO concentration (CO mol%) control, fresh makeup H 2The feed rate of the feedstock (e.g., the feed rate of the second part 25b) is adjusted to maintain the CO molar % or CO partial pressure in the FT synthesis stage, e.g., in the attrition reactor 200b of this stage. For example, this feed rate can be adjusted to maintain a setpoint or maximum CO molar % or CO partial pressure, which, in the case of the attrition reactor 200b, can be the measured CO molar % or CO partial pressure, or otherwise, the calculated CO molar % or CO partial pressure at the reactor inlet or upstream of the reactor (e.g., in the FT synthesis effluent or the attrition feedstock) (e.g., based on other parameters indicating the CO molar % or CO partial pressure). The feed rate is increased, for example, in response to a measured or calculated CO molar % or CO partial pressure exceeding the setpoint or maximum value, and conversely, decreased in response to a measured or calculated CO molar % or CO partial pressure below the setpoint or maximum value. The adjustment can include temporarily stopping the flow of the fresh make-up H 2 The flow of the feedstock can also include temporarily stopping the flow (i.e., adjusting the feed rate to zero) and then restarting the flow. The setpoint or maximum CO molar % in the total gas feed to stage 200b (including the combination of 12 and 25b) can be, for example, any optional discrete value from about 5 mol% to about 25 mol%, from about 3 mol% to about 15 mol%, or from about 1 mol% to about 10 mol%. The setpoint or maximum CO partial pressure can be, for example, any optional discrete value from about 34 kPa (5 psi) to about 1.38 MPa (200 psi), from about 34 kPa (5 psi) to about 689 kPa (100 psi), or from about 69 kPa (10 psi) to about 344 kPa (50 psi). As described herein, according to a preferred embodiment, fresh make-up H such as the second part 25b 2 The feedstock can be directly fed to an attrition reactor 200b disposed downstream of the FT reactor 200a.

[0117] In the FT synthesis stage, another process parameter that can be controlled instead of or in combination with the CO molar % control or CO partial pressure control is H 2 : the H:CO molar ratio, which can be particularly important from an operational perspective in the FT reactor of this stage. As described herein, a representative process is (a) in the FT synthesis stage, separated from the effluent of the FT synthesis stage, (i) H 2and CO 2 or (ii) a hydrogen source and CO 2 supplying at least a portion of the fraction rich in (i) H 2 and CO 2 or (ii) a hydrogen source and CO 2 to the reforming stage and / or the RWGS stage, and (b) separated from the effluent of the FT synthesis stage, (i) H 2 :CO molar ratio can be adjusted to maintain within a specific range. Similarly, the fraction 4a supplied to the reforming / RWGS reactor provides at least a portion of the feedstock to this reactor (e.g., as part of the feedstock 6 in Figure 1, or together with the feedstocks 2a and 25a in Figure 2). The feed rate of this fraction 4a rich in (i) or (ii) can be adjusted to change the stoichiometry of the feed to the reforming stage and / or the RWGS stage, whereby the H2:CO ratio of the effluent of the reforming stage and / or the RWGS stage is changed, which is supplied to the FT synthesis stage, thereby contributing to the maintenance of the setpoint or minimum H 2 :CO molar ratio in the FT synthesis stage. Such a setpoint or minimum H 2 :CO molar ratio can be a measured or calculated value (e.g., calculated based on the measured composition of the FT feedstock), and this setpoint or minimum H 2 :CO molar ratio can be any optional individual value within the ranges described herein for the syngas intermediate or the FT feedstock. For example, the setpoint or minimum H2 : The CO molar ratio can be any optional individual value within the range of about 2.1 to about 2.5. Depending on the composition (e.g., hydrogen content) of the fraction rich in (i) or (ii), for example, the measured or calculated H 2 : When the CO molar ratio is outside the target range, the feed rates of the further fractions 4b and 4a can be adjusted. Adjustment can include temporarily stopping the flow of this fraction or a part of this fraction (i.e., adjusting the feed rate to zero) and then restarting the flow. The adjustment can be based on an increase or decrease in the flow rate, or an increase or decrease in the proportion of the whole fraction represented by a part of the fraction supplied to the FT synthesis stage (e.g., the FT reactor 200a of this stage). As described herein, the part of fraction 14 rich in (i) or (ii) and supplied to the FT synthesis stage can be the second part 4b. For example, the gaseous feed mixture includes the first part 4a as a recycled gaseous feed mixture component, which is supplied to the reforming stage or the RWGS stage 100 (e.g., the reforming / RWGS reactor of this stage).

[0118] Regarding the separation and / or recovery of the liquid hydrocarbon product obtained from the FT synthesis stage, the effluent of this stage containing this product can be, according to certain embodiments, the FT synthesis effluent 12 as shown in FIG. 1, or the polished effluent 13 as shown in FIG. 2. As long as the polished effluent 13 is downstream of the FT synthesis effluent 12, separating the liquid hydrocarbon product from the polished effluent can similarly include separating it from the FT synthesis effluent. Thus, according to a representative process, the liquid hydrocarbon product can be included in the FT synthesis effluent (e.g., the effluent of the FT reactor 200a) or the polished effluent, and such a process can include C 4 + Separating the liquid hydrocarbon product containing hydrocarbons from each FT synthesis effluent or polished effluent can be included. Further, as described herein, (i) H 2 and CO 2 , or (ii) a hydrogen source and CO 2The fraction rich in [substance] can similarly be separated from each FT synthesis effluent or polishing effluent. For example, FIG. 1 shows the use of separation stage 300 to perform these separations (e.g., vapor / liquid separation) on the FT synthesis effluent 12, while FIG. 2 shows the use of separation stage 300 in a similar process to perform these separations on the polishing effluent 13. In either case, as a result of the separation stage 300, a liquid hydrocarbon product 16 containing, consisting of, or essentially consisting of hydrocarbons at room temperature is obtained, and this product is then further separated (e.g., fractionated) in the liquid product separation stage 400. As shown in FIG. 1, with respect to recycling the fraction rich in (i) or (ii) separated from the FT synthesis effluent 12, in the same process described herein, these fractions can be recycled in the same manner when separated from the polishing effluent 13 as shown in FIG. 2. For example, a typical process may further include recycling this fraction to the reforming stage or RWGS stage 100 (e.g., the reforming / RWGS reactor of this stage), and / or recycling it to the FT synthesis stage (e.g., the FT reactor of this stage), preferably recycling it to both stages. In some embodiments, the fraction rich in (ii) hydrogen source and CO 4 + is mainly CH 2 and is derived from the hydrogen source input to the process (e.g., a fresh gaseous feed mixture component, e.g., fresh make-up CO 4 and / or CH 2 and / or CH 4 -containing feedstock 2a), and / or is produced as a light hydrocarbon by-product of the FT synthesis and becomes a component of the "light fraction" fraction (ii) of the FT synthesis effluent. This fraction may contain other light hydrocarbons such as C 2 H 6 and / or C 3 H 8 .

[0119] As shown in both FIGS. 1 and 2, the process may further include fractionating the liquid hydrocarbon product 16, for example obtained from the separation stage 300, into one or more separated fractions rich in hydrocarbon types. For example, FIGS. 1 and 2 show a separated fraction 16b rich in hydrocarbons in the jet fuel boiling range (which can also be called the jet fuel boiling range fraction) and a separated fraction 16c rich in hydrocarbons in the diesel fuel boiling range (which can also be called the diesel boiling range fraction), while FIG. 2 also shows a separated fraction 16a rich in hydrocarbons in the naphtha boiling range (which can also be called the naphtha boiling range fraction). As long as these separated fractions are recovered as output from the process, they can contribute to the hydrocarbon yield and represent all or substantially all of the C 4 + hydrocarbons in the liquid hydrocarbon product, excluding the residual amount of these hydrocarbons that may be present in the condensed liquid water 9. As further described herein, a representative process may include recycling all or part of the separated fraction, thereby adjusting the product slate with respect to the proportion of hydrocarbon types recovered. For example, as shown in FIG. 2, at least a part of the naphtha boiling range fraction 16a, for example the hydrocarbon recycle 30b, may be recycled to the reforming stage or the RWGS stage 100. If only a part is recycled, the recovered portion 30a may represent the hydrocarbons recovered from the process that contribute to the hydrocarbon yield. 4 + As shown in FIG. 2, at least a part of the naphtha boiling range fraction 16a, for example the hydrocarbon recycle 30b, may be recycled to the reforming stage or the RWGS stage 100. If only a part is recycled, the recovered portion 30a may represent the hydrocarbons recovered from the process that contribute to the hydrocarbon yield. 4 + hydrocarbons recovered from the process that contribute to the hydrocarbon yield.

[0120] The following examples are described as representative of the invention. These examples should not be construed as limiting the scope of the invention, and considering the present disclosure and the appended claims, other equivalent embodiments will become apparent. Example 1 Reforming of the gaseous feed mixture

[0121] In a pilot plant scale experiment, a gas mixture was continuously fed into a reactor containing catalyst particles with a composition of 1 wt% Pt and 1 wt% Rh on a cerium oxide support. The performance of the reforming / RWGS system was tested at a WHSV of 0.9 h -1 , 864 °C (1587 °F), and a gauge pressure of 346 kPa (50 psig). The gas mixture tested was a composition containing methane, ethane, propane, and CO 2 in addition to H 2 O (an "IH 2 type feedstock"), which simulated that obtained from a combination of biomass hydrothermal cracking and hydroconversion, and then most of the hydrogen was removed by pressure swing adsorption (PSA). This gaseous feedstock mixture and the syngas product obtained from this feedstock ("IH 2 type product") are summarized in Table 1 below.

Table 1

[0122] From these results, it was found that the CO 2 -steam reforming catalyst and process showed a high hydrocarbon conversion rate and could provide a syngas product with an H 2 :CO molar ratio suitable for direct processing by a subsequent Fischer-Tropsch reaction (for example) without prior (upstream) adjustment of this molar ratio. Example 2 Fisher-Tropsch (FT) test

[0123] The FT test was carried out in an upward flow reactor with a 0.5-inch (6 mm) water jacket, using a mixture of 35% hydrocracking / isomerization catalyst (1% Ga-ZSM-5) and 65% Fischer-Tropsch catalyst (20% Co-1% Pt, 1% Rh), and then in a fixed bed polishing reactor using 100% Ga-ZSM-5 catalyst. All the catalysts were in the 35 - 60 mesh size range. The resulting liquid products were condensed and removed. The gas separated from this product was sent to a replicated FT + polishing reactor system, and additional liquid products were condensed and removed. In this process, a conversion rate of 50 - 60% can be achieved in each of the two reactor stages, and after sufficient time has elapsed for the system to reach a steady state, the final overall conversion rate through the two reactor stages far exceeds 65%. Next, the gas separated from the gas in the second stage was measured and analyzed. Even after more than 500 hours of testing with intermittent stops and restarts by hydrogen treatment, the deactivation of the Fischer-Tropsch catalyst was minimized. During the test period, several gallons of Fischer-Tropsch liquid were collected.

[0124] The FT system utilized an upward liquid-filled reactor with bubbling gas. This reactor had good heat transfer by the liquid, a water jacket for dissipating the heat of reaction, and good temperature uniformity by the diluted mixed catalyst. The results of the FT tests for the entire three test periods are shown in Table 2.

Table 2

[0125] The FT product was a high-quality colorless hydrocarbon liquid product with an oxygen content of less than 0.6 wt% and was easily separable from water. A typical distillation curve of this product is shown in Figure 3. This shows the relative amounts of hydrocarbons in the gasoline, jet fuel, and diesel boiling ranges. The composition of a typical FT gas product is shown in Table 3. This can be burned in a reformer to supply heat energy or recycled and consumed.

Table 3

[0126] The catalyst used for the reforming reaction in Example 1 was also effective for performing the RWGS reaction. At low temperatures, the equilibrium is favorable for methanation and low CO production. COCO 2 To achieve a high conversion rate from CO to CO, the RWGS reaction needs to be carried out at a sufficiently high temperature. Pt / Rh on a cerium oxide catalyst achieved a 75% conversion of CO in the product synthesis gas at 913 °C (1675 °F) and a gauge pressure of 103 kPa (15 psig) with an H 2 :CO molar ratio of 2.9. The experimental results are summarized in Table 4. 2

Table 4

[0127] According to modeling studies, the H 2 :CO molar ratio in the syngas is high at 2.9 for a typical FT feedstock, but this ratio decreased to 2.1 when combined with the recycled FT gas product. Example 4 Research on an electro-reformer

[0128] The reforming test was carried out using an electrically heated reformer with the catalyst described in Example 1 and a "H 2 type feedstock" having a composition of about 24 mol% IH 2 , 17.5 mol% methane, 17.5 mol% propane, and 41 mol% CO. The electric reactor heater was placed inside a sheath that protected it from exposure to the process gas, facilitating replacement even if the heater burned out. Typical experimental parameters and results for producing syngas from the gaseous feedstock mixture are summarized in Table 5. 2

Table 5

[0129] In total, the electro-reformer operated for over 500 hours in a reliable process, and no problems occurred even when the WHSV was increased from 0.7 to 1.5 hr -1 . As shown in Figure 4, the hydrocarbon conversion rate of the reformer was generally 90 - 95% during the operation period. As shown in Figure 5, the H 2 :CO molar ratio of the produced syngas was also constant during this period. This molar ratio was measured to be as low as 2.4, but the average value was higher, and this ratio can actually be adjusted as needed. As shown in Figure 6, the composition of the reformed product was also stable over time. The material balance during the operation period was centered around 100%, indicating the reliability of the measured parameters. Overall, the results demonstrate that the electro-reformer functions well over a long operation time in the production of syngas from a mixture containing methane and CO 2 , and is expected to bring favorable results for various raw materials such as biogas.

[0130] Overall, aspects of the present invention relate to a process for converting a low-value gaseous feed mixture into liquid hydrocarbon products using a reforming reaction and / or an RWGS reaction, where the liquid hydrocarbon products contain carbon derived from renewable resources such as CH 4 and 2 (the main component of biogas), etc., C 4 + hydrocarbons, and / or electrolytic H 2 , fossil hydrogen by CCS, biogas hydrogen, or methane pyrolysis hydrogen, and CO obtained from direct air capture, gasification of biomass, or combustion of biomass 2It includes. Additional processing steps can also achieve the desired hydrocarbon molecular weight distribution, if necessary, by FT synthesis alone or in combination with cracking. Those skilled in the art will recognize, based on the knowledge obtained from this disclosure, that various changes can be made to these processes to achieve these and other advantages without departing from the scope of this disclosure. Therefore, it should be understood that the features of this disclosure can be changed and / or substituted without departing from the scope of this disclosure. The specific embodiments shown and described herein are for illustrative purposes only and do not limit the invention described in the appended claims.

Claims

1. C ４ ＋ A process for producing a liquid hydrocarbon product containing hydrocarbons, In the reforming or RWGS stage, mainly (i) H ２ and CO ２ or (ii) a hydrogen source and CO ２ are contacted with a reforming / RWGS catalyst to produce a syngas intermediate containing an H ２ / CO mixture, and (b) A process comprising the step of converting a syngas intermediate into the liquid hydrocarbon product at least in part via Fischer-Tropsch (FT) synthesis in an FT synthesis stage.

2. The gaseous raw material mixture comprises (i) the H ２ and the CO ２ in a total amount of at least about 75 mol%, or (ii) the hydrogen source and the CO ２ in a total amount of at least about 75 mol%, the process according to claim 1.

3. The gaseous raw material mixture contains one or more of CO, H ２ O, and O ２ in an amount of less than about 10 mol% independently or in total, according to the process of claim 1 or claim 2.

4. The process according to any one of claims 1 to 3, wherein the gaseous feed mixture comprises biogas.

5. Said C ４ ＋ The hydrocarbon contains at least about 80% by weight in total of hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range, the process according to any one of claims 1 to 4.

6. The recovered C ４ ＋ The hydrocarbon contains hydrocarbons in the jet fuel boiling range in an amount of at least about 55% by weight, and the combination of hydrocarbons in the naphtha boiling range and hydrocarbons in the diesel boiling range accounts for at least about 40% by weight of the recovered C ４ ＋ The process according to any one of claims 1 to 5, wherein none of the liquid hydrocarbon products are recycled to the process

7. The recovered C ４ ＋ The hydrocarbon contains hydrocarbons in the jet fuel boiling range in an amount of at least about 80% by weight, and the hydrocarbons in the diesel boiling range account for at least about 15% by weight of the recovered C ４ ＋ The process according to any one of claims 1 to 5, wherein the hydrocarbons in the gasoline boiling range in the liquid hydrocarbon product are recycled to the process.

8. The process according to any one of claims 1 to 7, wherein the reforming / RWGS catalyst comprises a noble metal on a solid support comprising cerium oxide.

9. The process according to claim 8, wherein the noble metal is selected from the group consisting of Pt, Rh, Ru, Pd, Ag, Os, Ir, and Au.

10. The process according to claim 9, wherein the noble metal is Pt.

11. The process according to any one of claims 8 to 10, wherein the cerium oxide is present in an amount of at least about 60 wt% of the weight of the solid support.

12. The process according to any one of claims 8 to 11, wherein the solid support further comprises aluminum oxide.

13. The process according to claim 12, wherein the cerium oxide and the aluminum oxide are present in a total amount of at least about 95 wt% of the solid support.

14. The process according to any one of claims 1 to 13, wherein step (b) comprises a combination of the FT synthesis and wax cracking.

15. The process according to claim 14, wherein the FT synthesis stage comprises at least one FT reactor comprising a mixture of an FT catalyst and a cracking catalyst.

16. The process according to claim 15, wherein the FT synthesis stage further comprises at least one polishing reactor downstream of at least one FT reactor, the polishing reactor comprising a polishing catalyst and the FT catalyst being substantially absent from the polishing reactor.

17. The process according to claim 16, wherein the polishing catalyst has the same composition and / or the same form as the cracking catalyst.

18. The process according to claim 14, wherein the FT synthesis stage comprises at least one FT reactor comprising a bifunctional catalyst having an FT functional component and a cracking functional component.

19. The Fischer-Tropsch synthesis stage further includes at least one polishing reactor downstream of at least one Fischer-Tropsch reactor, the polishing reactor includes a polishing catalyst, and the polishing catalyst substantially does not contain the Fischer-Tropsch functional component, the process according to claim 18.

20. The process according to claim 19, wherein the polishing catalyst has the same composition as the cracking functional component.

21. The gaseous feed mixture includes one or more gaseous feed mixture components, and a part of the one or more gaseous mixture components is directly supplied to the at least one polishing reactor, the process according to any one of claims 16, 17, 19, and 20.

22. The one or more gaseous feed mixture components include one or more fresh gaseous feed mixture components and / or one or more recycled gaseous feed mixture components, the one or more gaseous feed mixture components are one of the one or more fresh gaseous feed mixture components, and a part of it is directly supplied to the at least one polishing reactor, the process according to claim 21.

23. The one or more gaseous mixture components directly supplied to the at least one polishing reactor are fresh feed H containing electrolyzed hydrogen ２ The process according to claim 22, which is a raw material containing

24. CO in the gaseous raw material mixture ２ At least about 70% of the carbon is C ４ ＋ The process according to any one of claims 1 to 23, which forms hydrocarbons.

25. A liquid hydrocarbon product containing hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range with a renewable carbon content of at least about 70%.

26. At least about 20% of the total carbon content of the liquid hydrocarbon product is CO ２ derived from, the liquid hydrocarbon product according to claim 25.

27. The above-mentioned CO ２ is the liquid hydrocarbon product according to claim 26, which is contained in the biogas.

28. Substantially all hydrocarbons in the gasoline boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range, wherein (i) at least about 20% of the total carbon content of the recovered C ４ ＋ hydrocarbon fraction is derived from CO in the atmosphere ２ and / or (ii) at least about 20% of the total hydrogen content of the recovered C ４ ＋ hydrocarbon fraction is derived from electrolytic hydrogen, the recovered C ４ ＋ hydrocarbon fraction.

29. A process for producing a liquid hydrocarbon product containing hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, and / or hydrocarbons in the diesel boiling range, In the reforming or RWGS stage, mainly (i) H ２ and CO ２ or (ii) a hydrogen source and CO ２ contacting a gaseous feed mixture containing with a reforming / RWGS catalyst to produce a syngas intermediate containing an H ２ / CO mixture, and (b) In the Fischer-Tropsch (FT) synthesis stage, converting a synthesis gas intermediate to the liquid hydrocarbon product through Fischer-Tropsch (FT) synthesis combined with wax cracking.

30. Said step (b) comprises contacting an H ２ / CO mixture with a mixture of an FT catalyst and a cracking catalyst to provide an FT synthesis effluent, the process according to claim 29.

31. The process according to claim 30, wherein the cracking catalyst includes one or more cracking active metals selected from Groups 12 to 14 of the periodic table.

32. The process according to claim 30 or claim 31, wherein step (b) further includes contacting the Fischer-Tropsch synthesis effluent with a polishing catalyst in a state where the Fischer-Tropsch catalyst is substantially absent to obtain a polished effluent.

33. Said step (b) comprises contacting an H ２ / CO mixture with a bifunctional catalyst having an FT functional component and a cracking functional component to provide an FT synthesis effluent, the process according to claim 32.

34. The process according to claim 33, wherein the cracking functional component comprises one or more cracking active metals selected from Groups 12 to 14 of the periodic table.

35. The process according to claim 33 or claim 34, wherein step (b) further comprises contacting the FT synthesis effluent with a polishing catalyst substantially free of the FT functional component to obtain a polished effluent.

36. In said step (b), said polishing catalyst contains at least about 50 mol% of H ２ and, in addition to the fresh feed H ２ -containing feedstock directly supplied to said polishing catalyst, is contacted with the FT synthesis effluent, the process according to claim 32 or claim 35.

37. The process according to claim 31 or claim 34, wherein the one or more cracking active metals are deposited on a solid acidic support.

38. The process according to claim 37, wherein the solid acidic support comprises a zeolite molecular sieve having a molar framework ratio of silica to alumina of less than about 50.

39. The liquid hydrocarbon product is contained in the FT synthesis effluent, and the process C ４ ＋ separating a liquid hydrocarbon product containing hydrocarbons from the FT synthesis effluent, and (i) H ２ and CO ２ or (ii) separating a fraction rich in a hydrogen source and CO ２ from the FT synthesis effluent, the process according to any one of claims 1 to 15, 18, 29 to 31, 33, 34, 37, and 38, further comprising.

40. The liquid hydrocarbon product is contained in the polished effluent, and the process Said C ４ ＋ Separating a liquid hydrocarbon product containing hydrocarbons from said polishing effluent, and (i) H ２ and CO ２ or (ii) separating a fraction rich in a hydrogen source and CO ２ from the polishing effluent, the process according to any one of claims 16, 17, 19 to 23, 32, 35, and 36, further comprising the step of.

41. Said (i) H ２ and CO ２ or (ii) a fraction rich in a hydrogen source and CO ２ contains CH ４ The process according to claim 39 or claim 40, wherein the fraction rich in said (i) H and CO or (ii) a hydrogen source and CO contains CH.

42. Furthermore, (i) H ２ and CO ２ or (ii) recycling a fraction rich in a hydrogen source and CO ２ to a reforming stage or an RWGS stage, and / or (i) H ２ and CO ２ or (ii) recycling a fraction rich in a hydrogen source and CO ２ to the FT synthesis stage, the process according to any one of claims 39 to 41.

43. The process according to any one of claims 1 to 24 and 29 to 42, further comprising fractionating the liquid hydrocarbon product into one or more separated fractions enriched in hydrocarbons in the naphtha boiling range, hydrocarbons in the jet fuel boiling range, or hydrocarbons in the diesel boiling range.

44. The process according to claim 43, wherein the one or more separated fractions comprise a hydrocarbon fraction in the naphtha boiling range, and the process further comprises recycling at least a portion of the hydrocarbon fraction in the naphtha boiling range to a reforming stage or an RWGS stage.

45. The process according to any one of claims 1 to 24 and 29 to 44, wherein the gaseous feed mixture comprises biogas present as a fresh gaseous feed mixture component in the gaseous feed mixture.

46. The gaseous raw material mixture contains fresh make-up H containing electrolytic hydrogen ２ The process according to any one of claims 1 to 24 and 29 to 45, comprising a feedstock containing

47. said fresh feed H ２ The process according to claim 46, further comprising the step of directly feeding a portion of the feedstock containing to the FT synthesis stage.

48. The process according to any one of claims 1 to 24 and 29 to 47, wherein the reforming / RWGS catalyst is disposed within the catalyst bed volume in an electrically heated reforming reactor.

49. The process according to claim 48, wherein the electrically heated reforming reactor is heated internally and / or externally by a resistive heating element and / or an inductive heating element.

50. The hydrogen source is CH ４ , C ２ H ６ , C ３ H ８ , and H ２ O, and the process according to any one of claims 1 to 24 and 29 to 49, which comprises one or more of them.

51. The hydrogen source is: (i) H ２ and CO ２ or (ii) a hydrogen source and CO ２ CH ４ , C ２ H ６ , C ３ H ８ and the fraction comprises one or more of: ４ ＋ 51. The process of claim 50, wherein the hydrocarbon products are separated from the FT synthesis stage effluent containing the hydrocarbon products and further recycled to the reforming stage or the RWGS stage.

52. The process according to claim 51, wherein the effluent of the FT synthesis stage is the FT synthesis effluent or the polished effluent.

53. The gaseous raw material mixture is fresh make-up H which is input to the process ２ The process according to any one of claims 1 to 24 and 29 to 52, comprising a first portion of the feedstock containing the raw material

54. said fresh feed H ２ The process according to claim 53, further comprising the step of directly feeding a second portion of the feedstock containing to the FT synthesis stage.

55. said fresh feed H ２ The process according to claim 54, wherein the feed rate of the second part of the feedstock is adjusted to maintain the CO partial pressure in the FT synthesis stage. Claim 56 said fresh feed H ２ comprising the step of directly feeding a second portion of the feedstock containing said fresh feed H to the attrition reactor of the FT synthesis stage, said attrition reactor being downstream of the FT reactor, ２ Process according to claim 55, wherein the feed rate of the second portion of the feedstock containing said fresh feed H is adjusted to maintain the CO partial pressure in the attrition reactor. Claim 57 A process according to any one of claims 1 to 24 and 29 to 56, comprising the step of feeding a fraction rich in (i) H ２ and CO ２ , or (ii) a hydrogen source and CO ２ separated from the effluent of the FT synthesis stage, to the FT synthesis stage. Claim 58 The process according to claim 57, wherein a portion of the fraction rich in (i) or (ii) is fed to the FT reactor to provide at least part of the FT feedstock, and the effluent from the FT synthesis stage from which the fraction rich in (i) or (ii) has been separated is the FT synthesis effluent or the polishing effluent. Claim 59 The feed rate of a part of the fraction rich in (i) or (ii) is adjusted to maintain the H ２ :CO molar ratio in the FT synthesis stage, the process according to claim 57 or claim 58. Claim 60 The process according to claim 59, wherein the portion of the fraction rich in (i) or (ii) is the second portion, and the gaseous feed mixture comprises the first portion of the fraction rich in (i) or (ii).

Images