Synthesis process of high-value, low-carbon chemical products

Abstract

The present invention describes an improved method for synthesizing high value chemical products from low carbon synthesis gas. In one aspect, a method for producing chemicals is provided. The process includes: feeding a feedstock comprising hydrogen and carbon monoxide to a liquid fuel production reactor, the liquid fuel production reactor comprising a catalyst, thereby producing a product, the product comprising a liquid phase and a solid phase, the liquid phase being a C5-C 23 and an oxygenated hydrocarbon, said solid phase being C 24 -C 45 The liquid phase comprises 51 to 99% by volume of the product, and contains aliphatic hydrocarbons.

Description

[Technical Field]

[0001] This invention describes an improved method for synthesizing high-value chemical products from low-carbon synthesis gas. The first step of the method involves a catalytic reaction of synthesis gas in a liquid fuel production (LFP) catalytic reactor using an advanced catalyst, in which the minimum concentration of wax (C) is added. 24 + hydrocarbons) and the maximum concentration of n-1-alkenes, mainly C5-C 23 It produces a liquid product. This LFP C5-C 23 Liquid product ("liquid product") and LFP C 24 +The solid product is further processed to produce a high-value chemical product. When renewable or low-carbon raw materials are used, these chemical products have the additional advantage of being high-value and environmentally friendly (green) synthetic chemicals. Additional processing includes at least one of many processing steps, including: 1) Distillation and / or use of a solid adsorbent to remove C5-C 23 1) Separating specific high-value normal paraffins, normal 1-olefins and normal 1-hydroxyalkanes from the liquid product; 2) C5-C 23 The liquid product is treated in a catalytic oligomerization reactor to convert n-1-olefins into lubricants, and the unconverted C5-C 23 Step 3) Separation from liquid product; Step 4) Convert n-1-olefin to n-1-hydroxyalkane; Step 5) Using catalytic hydrogenation, C5-C 23 The process involves converting a liquid product into jet fuel, followed by distillation of the hydrogenated product to obtain jet fuel, diesel fuel, and naphtha. In addition, post-treatment of both the liquid and solid products can yield a variety of high-value products, including solvents, n-paraffins, α-olefins, lubricants, ethylene and propylene, polyethylene and polypropylene, high-performance waxes (e.g., ski waxes), packaging, paints, coatings, cosmetics, flavors and fragrances, dyes, plastic resin products, consumer products, and other high-value chemicals.

BACKGROUND ART

[0002] A mixture of H2 and CO is called synthesis gas or syngas. Synthesis gas can be produced from various sources. Coal can produce synthesis gas by gasification, natural gas can produce synthesis gas by reforming with steam or oxygen in an autothermal reforming system or a partial oxidation system, biomass such as woody biomass, agricultural residues or other organic substances, and municipal waste can produce synthesis gas by gasification. A pyrolysis system can be used to produce synthesis gas and other products such as pyrolysis oil from biomass. Hydrogen can be produced from the electrolysis of water, and carbon monoxide can be produced from carbon dioxide and hydrogen by the reverse water gas shift (RWGS) reaction. The RWGS reaction is also called CO2 hydrogenation.

[0003] Synthesis gas can be used as a raw material for producing a wide range of chemical products. Such chemical products include liquid fuels, hydroxyalkanes (alcohols), acetic acid, dimethyl ether, olefins, and many other chemical products. Since it is not practical to transport synthesis gas to remote refineries or chemical processing plants, synthesis gas needs to be directly produced at the production site and converted into fuels and / or chemicals.

[0004] The catalytic hydrogenation of carbon monoxide produces light gases, liquids and waxes, which range from methane to heavy hydrocarbons (C 100 and above), and in addition to oxygenated hydrocarbons. This catalytic hydrogenation is typically called Fischer reactor feed (or F-T) synthesis. Conventional low temperature (<250 °C) F-T processes produce mainly high molecular weight F-T waxes (C 24 -C 100 ). These F-T waxes typically account for about 65% by volume of the total carbon-containing products. The remaining 35% by volume is C5-C 23It is composed of liquid hydrocarbons. These FT liquid hydrocarbons include n-alkanes, small amounts of n-alkenes, n-hydroxyalkanes (alcohols), and branched alkanes. C5-C 12 Hydrocarbons in this range are typically referred to as naphthas.

[0005] FT waxes are hydrocracking and / or further processed to produce diesel, naphtha, and other products. Since light hydrocarbons are also produced during this hydrocracking process, further improvements may be necessary to produce usable products (Ail et al, 2016).

[0006] Attempts have been made to improve the value of the FT liquid fraction to produce higher-value products. For example, UOP's Cat Poly process is used at Sasol's FT plant in South Africa to oligomerize light olefins (alkenes) into diesel. The Cat Poly process uses a solid phosphoric acid (SPA) catalyst to convert light olefins into diesel fuel. However, because the oligomer product is highly branched, it has a low cetane index and needs to be blended with diesel with a higher cetane index to meet the overall diesel fuel specifications (de Klerk, 2008). In addition, the low concentration of olefins in the FT liquid fraction makes this approach economically impractical.

[0007] Greyrock contains approximately 95% by volume of C1-C depending on the catalyst operating conditions. 23 Liquid hydrocarbons and up to 5% by volume of C 24 -C 45 We have developed an innovative catalyst that primarily produces hydrocarbon products composed of hydrocarbons (waxes) (Schuetzle et al; US Patents 2013, 2015, 2017, 2018, 2019; Canadian Patents 2017, 2018). This liquid hydrocarbon fraction is mainly composed of n-aliphatic hydrocarbons, n-1-alkenes, and n-1-hydroxyalkanes.

[0008] Table 1 summarizes the relationship between the H2 / CO synthesis gas ratio and the concentrations of the naphtha, diesel, and wax fractions. The naphtha fraction is defined as the total (volume %) of C5-C8 hydrocarbons and 50% of C9 hydrocarbons. The diesel fraction is defined as the total (volume %) of 50% of C9 hydrocarbons and C 10 -C 23 hydrocarbons. The LFP solid product is composed of normal aliphatic hydrocarbons (alkanes) in the range of C 24 -C 45 As shown in Table 1, even when the H₂ / CO ratio of the synthesis gas decreases from 2.00 / 1.00 to 0.55 / 1.00, the amount of the naphtha fraction does not change. However, when the H₂ / CO ratio decreases, the diesel fraction slightly decreases while the wax fraction increases.

[0009]

Table 1

[0010] Table 2 summarizes the relationship between the H₂ / CO ratio and the distribution of normal alkanes, branched alkanes (isoalkanes), normal 1-alkenes, and normal 1-hydroxyalkanes in the directly produced LFP liquid product (catalyst operating conditions: T: 415°F, P: 315 psi, SV: 1,750). At a low H₂ / CO ratio of 0.55, the C5-C 16 normal 1-alkenes increase from 4.5 volume % to 34.8 volume %. However, there is not much significant change in the amount of C3-C 12 normal hydroxyalkanes (2.8 - 4.3 volume %), or isoalkanes (5.8 - 8.2 volume %).

[0011]

Table 2

[0012] In a typical F-T process, the solid fraction (C24 -C 100 ) and liquid fraction (C5-C 23 Because (Gruber et al, 2019, Fedou et al, 2020) is generated, there was no economic incentive to convert this small amount of liquid fraction into a higher-value product. Consequently, there is little prior art related to converting these liquids into higher-value products.

[0013] Table 3 compares the amounts of chemical components produced from catalytically converted synthesis gas by this improved LFP process with those of a typical FT process. In the FT process, n-1-alkenes and n-1-hydroxyalkanes are produced at low concentrations, averaging approximately 3.0 vol% and 1.0 vol%, respectively. Therefore, separating specific n-1-alkenes and n-1-hydroxyalkanes from the liquid fraction is not economically viable.

[0014] Table 3 compares the chemical composition produced from synthesis gas conversion using this improved LFP process. This process operates with a low synthesis gas H2 / CO ratio of approximately 0.55, which significantly increased the production of n-1-alkenes to approximately 35 volume percent of the total liquid and solid fractions. Although the solid fraction in this improved LFP process produces only about 8.0 volume percent of n-alkanes (wax), this wax is more economically valuable than typical FT wax.

[0015] Since the FT process produces n-alkanes at approximately 30% by volume, there are few or no reported techniques for developing processes to improve this small fraction into higher-value products. Instead, several processes for improving combined liquid and solid products have been described.

[0016] Farshid et al (2009) separated the products obtained by FT catalytic conversion of synthesis gas into a condensed (liquid) fraction and a heavy (solid) fraction. They hydrocracked the solid fraction using multiple catalyst beds, thereby shortening the carbon chain length. The products obtained from this hydrocracking were then combined with the liquid fraction. This combined fraction was processed using conventional petroleum refining processes to produce fuel and intermediate fractions.

[0017] Tanaka et al (2015) describe distilling the combined liquid and solid fractions to obtain the middle and wax fractions. Subsequently, the middle fraction was distilled to obtain the second middle fraction and the light fraction. Since the normal 1-alkenes and normal 1-hydroxyalkanes in the FT middle fraction were present at low concentrations (Table 3), they did not attempt to separate these species from the normal alkanes.

[0018] In contrast, this improved LFP process produces a high proportion (more than 90 vol%) of liquid hydrocarbons (compared to approximately 35 vol%) in the FT process, eliminating the need to process heavy fractions (such as waxes). Furthermore, the operating conditions of this improved LFP process can be easily adjusted to produce a large amount (more than approximately 32 vol%) of n-1-alkenes (compared to approximately 3 vol%) in the FT process (Table 3).

[0019] [Table 3] [Overview of the project]

[0020] The present invention relates to a method for directly converting synthesis gas into liquid fuel in a catalytic liquid fuel production (LFP) reactor using a novel catalyst, wherein the catalyst, when operated under the conditions of H2 / CO: 2.1, temperature: 415°F, pressure: 315 psi, and space velocity per hour: 1,750, contains 75% or more by volume, 80% or more by volume, 90% or more by volume, and more preferably 95% or more of C5-C23 A hydrocarbon and C in an amount of 25% by volume or less, 20% by volume or less, 10% by volume or less, more preferably 5% by volume or less. 24 This invention relates primarily to a method for producing a mixture containing a small proportion of heavier hydrocarbons.

[0021] This LFP product is processed to produce chemical products with much higher economic value than diesel fuel and naphtha. This processing includes at least one of several additional steps, including: 1) separating specific normal paraffins (or n-alkanes) from the LFP product by distillation; 2) separating specific normal 1-alkenes (or 1-alkenes) from the LFP product by distillation; 3) separating normal 1-hydroxyalkanes from the LFP product by distillation; 4) catalytically hydrating olefins in the LFP product to normal hydroxyalkanes; and 5) catalytically oligomerizing olefins in the LFP product into lubricants. Several embodiments of the present invention include combinations of these five processing steps. Simply distilling this LFP product yields LFP naphtha products and LFP diesel products.

[0022] Table 4 summarizes the commercial value of LFP naphtha and LFP diesel in comparison to several specific chemical products that may be produced as described in this document. These commercial values ​​are subject to change and do not include regulatory incentives such as low-carbon credits, including RINs, LCFSs, or other environmental credit candidates.

[0023] LFP naphtha and LFP diesel have a commodity value similar to crude oil, as indicated by the West Texas Intermediate (WTI) crude oil price. Table 4 also shows the commodity values ​​of other possible products that can be produced from LFP products, as described in this document. The second column of Table 4 shows the price ratio of the various products to the value of WTI crude oil. As can be seen from this, the current commercial value of all other products listed in this table is up to approximately 280 times that of LFP products, LFP naphtha, and LFP diesel.

[0024] [Table 4]

[0025] In the embodiment of the separation of normal paraffins, the unfractionated LFP product is C5-C 23 The mixture contains n-paraffins (Table 1). n-paraffins have economic value as industrial solvents. For example, n-heptane is a more environmentally safe solvent than hexane, benzene, or toluene. The LFP reactor may be operated to reduce the 1-alkenes and alcohols in the LFP naphtha and increase the production of n-paraffins. This can be done by increasing the hydrogen relative to carbon monoxide in the LFP reactor, as shown in Table 2. Since the boiling point of hexane is 65°C while that of heptane is 98°C, this LFP product may be further processed in a single or series of distillation columns to separate the various n-paraffins using the difference in boiling points. The boiling points of the other components are also different from those of heptane. The boiling point of heptane is 94°C, and that of octane is 126°C. In this way, industrial-grade n-heptane can be produced as a product from the LFP liquid product. The purity of the n-heptane is at least 95% by volume, more preferably over 98% by volume, and even more preferably better than 99% by volume. It should be noted that the wholesale price of all n-paraffin products exceeds that of unfractionated LFP liquid products.

[0026] In embodiments of the separation of normal 1-alkenes, the LPF liquid product consists of a mixture of 1-alkenes, as summarized in Table 2. The LFP reactor may be operated to reduce the n-paraffin and increase the production of 1-alkenes to about 34% by volume or more. This can be done by reducing the ratio of hydrogen to carbon monoxide in the LFP reactor synthesis gas feedstock, but this can also be influenced by temperature, pressure, and flow rate / gas time-space rate.

[0027] In the embodiment of the separation of n-1-hydroxyalkanes, the LPF liquid product is C3-C 16 It is composed of a mixture of n-1-hydroxyalkanes. While reducing the H2 / CO ratio of the synthesis gas increases its concentration from 2.8 vol% to 4.3 vol%, the amount remains quite low (Table 2). However, as shown in Table 3, the commercial value of n-1-hydroxyalkanes is very attractive.

[0028] Since some n-1-hydroxyalkanes typically have a higher commercial value than n-1-alkenes, n-1-alkenes can be converted to n-1-hydroxyalkanes by catalytic hydration. A molybdenum-tungsten heteropoly acid impregnated into a zeolite substrate is used as the catalyst for this conversion. This reaction proceeds with high selectivity at approximately 300 psi and 550°F.

[0029] In another embodiment, the n-1-alkene is converted into a synthetic lubricant. This is done by converting the n-1-alkene contained in the unfractionated LFP product into various types of synthetic lubricants using catalytic oligomerization. By changing the operating conditions of the oligomerization process, lubricants of various viscosities are produced. The lubricants are easily separated from the unconverted fuel by distillation. [Brief explanation of the drawing]

[0030] [Figure 1]Figure 1 shows the normal hydrocarbon distribution of LFP-treated wax. [Figure 2] Figure 2 shows the distribution of n-alkanes (paraffins), n-1-alkenes, and n-1-hydroxyalkanes in the LFP liquid product. Paraffins are the longest of the three groups, n-1-alkenes are of intermediate length, and 1-hydroxyalkanes are the shortest. [Modes for carrying out the invention]

[0031] The present invention relates to a method for directly converting synthesis gas into liquid fuel in a catalytic liquid fuel production (LFP) reactor using a novel catalyst, wherein C5-C 23 It mainly produces a mixture of hydrocarbons (referred to as LFP products in this document), but the C that is associated with this mixture 24 The present invention relates to a method in which hydrocarbons with larger molecular weights constitute less than approximately 10% by volume, preferably less than approximately 5% by volume. The selectivity of the product can be adapted based on the operating conditions of the plant and the trading opportunities in the market.

[0032] In one embodiment, the synthesis gas is a low-carbon synthesis gas derived from the conversion of biomass or other renewable resources by gasification, or a low-carbon synthesis gas derived from a process that converts captured carbon dioxide, or a process that converts biogas into synthesis gas, or a process that converts any other low-carbon material into synthesis gas. In this embodiment, the synthesis gas is produced using a catalytic RWGS reaction, thereby converting carbon dioxide and hydrogen into carbon monoxide and water. Hydrogen can be produced from various sources, including the electrolysis of water. After the water is removed by cooling, the desired dry synthesis gas (i.e., synthesis gas) consists of CO and unconverted H2 and CO2.

[0033] One embodiment of the present invention includes a liquid fuel production (LFP) reactor system, also known as a hydrocarbon synthesis step. The LFP reactor primarily uses CO and H2 to produce C5-C2, which can be used as liquid fuel and / or chemicals. 23 It is converted into hydrocarbons.

[0034] An LFP reactor is a multi-tube fixed-bed reactor system. The diameter of each LFP reactor tube can be 13 mm to 26 mm. The length of the reactor tubes is usually longer than 6 meters, more preferably longer than 10 meters. LFP reactors are usually positioned vertically, and the LFP reactor feedstock is introduced from the top of the LFP reactor. However, depending on the circumstances, the reactor can also be positioned horizontally, and in situations where height is limited, it may be advantageous to position the reactor at an angle. The majority of the length of the LFP reactor tube is filled with LFP catalyst. This LFP catalyst may be blended with diluents such as silica or alumina to assist in the dispersal of LFP reactor feedstock into and through the LFP reactor tubes and to control the thermal profile. The chemical reactions occurring in the LFP reactor produce liquid hydrocarbon products (C3-C3 23 LFP product gases containing hydrocarbons and water are generated. Less than 2% of the carbon monoxide in the LFP reactor feedstock is converted to carbon dioxide within the LFP reactor. Of the carbon monoxide in the LFP reactor feedstock, C 24 It is also important to note that only a small amount is converted into hydrocarbons with a larger number of carbon atoms.

[0035] However, the LFP catalyst used in one embodiment of the present invention contains approximately 65% ​​by volume of C 24 -C 100 Compared to a typical Fischer-Tropsch (FT) process that produces hydrocarbons, C5-C 23 It mainly produces hydrocarbons, and the C associated with this 24 +Hydroxides are present at the minimum concentration (less than 25% by volume, less than 10% by volume, preferably less than about 5% by volume). In a typical FT process, the wax is C 100It is not uncommon for this to exceed. The LFP catalyst is supported on a metal oxide support selected from the group of alumina, silica, titania, activated carbon, carbon nanotubes, zeolites, or other support materials having sufficient size, shape, pore size, surface area, fracturing strength, and effective pellet radius, or mixtures thereof. This catalyst can have various lobed supports of various shapes, the lobed supports having three, four, or five lobes, of which two or more lobes are longer than the other two shorter lobes, and both of the longer lobes are bilaterally symmetrical. The distance from the midpoint of the support or the midpoint of each lobe is called the effective pellet radius, C5-C 23 This is an important parameter for achieving the desired selectivity for hydrocarbons. The LFP catalyst promoter may include one of cerium, ruthenium, lanthanum, platinum, rhenium, gold, silver, nickel, or rhodium. These promoters can be used individually or in combination with each other. The LFP catalyst promoter is less than 1% by weight of the total catalyst, preferably less than 0.5% by weight, and more preferably less than 0.1% by weight.

[0036] The LFP catalyst support has a pore diameter greater than 8 nanometers (nm), an average effective pellet radius of less than 60 micrometers (μm), a crushing strength greater than 3 lbs. / mm, and a strength of 150 m 2 It possesses a BET surface area exceeding / g. The catalyst, after metal impregnation, has a metal dispersion degree of approximately 4%.

[0037] The LFP fixed-bed reactor is C5-C 23The reactor is operated to maximize the yield of hydrocarbons and oxygenated hydrocarbons. In one embodiment, the LFP reactor is operated at a pressure in the range of 11.4 to 32.0 bar (150 to 450 psig), more typically in the range of 300 to 350 psi. The reactor is operated in a temperature range of 177°C (350°F) to 238°C (460°F), more typically at approximately 210°C (410°F). Since this catalytic reaction is exothermic, the reactor temperature is maintained inside the LFP reactor tubes by placing a bundle of reactor tubes in a heat exchanger and having water outside the LFP reactor tubes within this heat exchanger. The vapor pressure is controlled on the shell side of the reactor, and since the temperature is lower than the reaction temperature of the LFP, heat flows from the LFP reactor tubes to the cooler vapor. The vapor temperature is maintained by maintaining the pressure of the vapor (usually saturated vapor).

[0038] In another embodiment, the LFP reactor is operated in a mode that maximizes the amount of n-1-alkene product for use in the downstream oligomerization reactor. The LFP reactor is typically operated at an H2 / CO ratio (volume / volume) of 1.7–2.2 and a temperature of around 210°C (410°F), but as summarized in Table 2 above, reducing the H2 / CO ratio can increase the proportion of n-1-olefin in the LFP product. Operating at a lower H2 / CO ratio significantly increases the concentration of n-1-alkene, however C 24 +Hydroxides (waxes) also increase from approximately 4% by volume to 8% by volume (Table 2). As will be explained in detail in a later section, as shown in Figure 1, this C 24 +Hydroxides are mainly C 24 -C 40 It is a light crystalline wax composed of normal aliphatic hydrocarbons.

[0039] This lightweight crystalline wax differs significantly from the heavy amorphous wax produced by conventional FT processes. Such lightweight crystalline waxes are highly valuable because they are typically used as waxes for skis, cars, furniture, and other products.

[0040] In operating the LFP reactor, the maximum amount of normal 1-olefin raw material available for use in the downstream oligomerization reactor is produced by balancing a slight increase in temperature between 210°C (410°F) and 221°C (430°F) with a reduction in the H2 / CO ratio to 0.50 / 1.00 (Table 2).

[0041] The CO conversion in the LFP reactor is maintained at 40-60 volume% CO per pass. The CO can be reused for further conversion or sent to additional LFP reactors downstream. The carbon selectivity for CO2 is minimized to less than 4%, more preferably less than 1%, of the converted CO. C5-C 24 The carbon selectivity for hydrocarbons is 60-85%. The LFP product contains the desired C5-C 24 Along with liquid aliphatic hydrocarbons and oxygenated hydrocarbons, unreacted carbon monoxide, hydrogen, small amounts of C1-C4 gaseous hydrocarbons and small amounts of C 24 It contains hydrocarbons.

[0042] The target C5-C 23 The LFP reactor product, which contains liquid hydrocarbons, may be further processed in a separation system. This separation system may include distillation. 23 The products can be used for gasoline blend stock, diesel fuel, jet fuel, or as low-carbon chemicals that can replace petroleum or natural gas-derived chemicals. In one embodiment, the LFP products are sent to a series of fractional distillation columns used to produce high-cetane diesel fuel with a flash point adjustable between 38 and 54°C (100 and 130°F) and stabilized naphtha (potentially for gasoline blend stock or chemical feedstock). Basic equipment for these columns includes:

[0043] Wax strip tower - This unit uses steam to remove waxy C 24+Fuel range components are recovered from the material. The top fuel range components and steam are sent to the main fractionation column, and the stripped wax is sent to the high-temperature storage. The wax strip column is a column without a condenser or reboiler and is operated at approximately 170°C (340°F) with a pressure of 40 psig, which is sufficient pressure for the top steam to enter the main fractionation column.

[0044] Main fractionation column – This column separates the raw fuel into naphtha components and diesel range components, thereby controlling the diesel flash point. This column includes a high-pressure (HP) steam-heated reboiler and an external condenser with a three-phase separation function to remove water and steam adsorbed from the feedstock of the wax strip column.

[0045] Naphtha stabilization tower (optional) - This process controls the Reed vapor pressure (RVP) to the standard 8 psia. This stabilization tower includes a low-pressure (LP) steam reboiler and an integrated knockback water-cooled condenser.

[0046] Diesel cold flow / kerosene vacuum tower (optional) - This process is used to adjust the diesel pour point for sale in cold climates and / or to produce a kerosene fraction. The raw material is heated to 300°C (570°F). The tower has 20 stages, and the pressure at the top condenser is 6 psia. This kerosene fraction can be used as a jet fuel component. Under certain conditions, this kerosene fraction can meet the ASTM specification (ASTM D7566) for use as jet fuel.

[0047] In one embodiment of the present invention, the kerosene fraction of the LFP liquid product does not fully meet the ASTM D7566 standard for use as jet fuel, and in order to meet the specifications for use as jet fuel, the LFP liquid product, or a fraction of the LFP liquid product such as LFP kerosene or LFP light diesel, may need to be lightly hydrogen-isomerized. The LFP liquid product or a fraction of the product is pressurized and mixed with a hydrogen-containing stream. Hydrogen can be produced by electrolysis of water, reforming of natural gas, gasification of waste or biomass, or other methods for producing low-carbon hydrogen.

[0048] A mixed stream containing hydrogen and at least a portion of the LPF liquid product is heated and supplied to the hydrogen isomerization reactor. The hydrogen isomerization reactor operates at a high pressure exceeding 100 psig, but this pressure is typically less than 2,000 psig. The hydrogen isomerization reactor operates at a temperature of 250°C to 400°C. The product from the hydrogen isomerization reactor is cooled before entering the high-temperature separator, where the gas and liquid are separated in the high-temperature and low-temperature separators.

[0049] Hydrocarbon products from the high-temperature and low-temperature separators are sent to a fractionation section, where the light end and hydrocarbon products are separated. This fractionation system may include a wax strip column and a main fractionation column, as well as a naphtha stabilization column and a kerosene vacuum column. The fractionation column is operated so that the kerosene flow meets the specifications of ASTM D7566.

[0050] In one embodiment of the present invention, the economic value of the LFP liquid product is increased by at least one of the following means: 1) separating the flow from the LFP liquid product, wherein the separated flow contains at least 70 vol%, at least 80 vol% and more preferably at least 95 vol% of a specific n-paraffin (e.g., n-heptane); 2) separating the flow from the LFP liquid product, wherein the separated flow contains at least 70 vol%, at least 80 vol% and more preferably at least 95 vol% of a specific n-α-alkene; 3) separating the flow from the LFP liquid product, wherein the separated flow contains at least 70 vol%, at least 80 vol% and more preferably at least 95 vol% of a specific n-hydroxyalkane; 4) further processing the LFP liquid product in an oligomerization reactor, wherein at least a portion of the olefins in the liquid product is converted into a lubricant or other hydrocarbon product having a viscosity index of at least 80 and more preferably at least 95.

[0051] In one embodiment of the present invention, the LFP reactor may be operated to reduce the n-1-alkenes and n-1-hydroxyalkanes in the LFP liquid product and increase the production of n-paraffins. This can be done by increasing the amount of hydrogen relative to carbon monoxide in the LFP reactor feedstock. The LFP liquid product can be further processed in one or two distillation columns to separate the various n-paraffins using the difference in boiling points. For example, the boiling point of hexane is 65°C, while that of heptane is 98°C. The boiling points of other materials available in the LFP liquid product are also different from that of heptane or other desired products. The boiling point of heptane is 94°C, and that of octane is 126°C. In this way, industrial-grade n-heptane can be produced as a product from the LFP liquid product. The purity of the n-heptane is preferably greater than 95% by volume, more preferably 98% by volume, and even more preferably greater than 99% by volume. Other n-paraffin products (e.g., n-hexane, n-octane, n-nonane, n-pentane, n-decane) can also be produced by similar methods with similarly preferred purity.

[0052] In one embodiment of the present invention, the LPF liquid product contains a mixture of n-1-alkenes. The LFP reactor may be operated to reduce n-paraffin and increase the production of 1-alkenes. This can be done by reducing the ratio of hydrogen to carbon monoxide in the LFP reactor feedstock (Table 2). The economic value of the LFP liquid product is increased by separating a stream from the LFP liquid product, the separated stream preferably containing 95 vol% of specific n-1-alkenes, more preferably 98 vol% of specific n-1-alkenes, and even more preferably 99 vol% of specific n-1-alkenes. This separation is achieved by distillation based on the difference in normal boiling points of the various LPF liquid product components. In this way, various C5-C 16 Normal 1-alkenes can be separated.

[0053] In one embodiment of the present invention, the LFP liquid product is catalytically converted in an oligomerization reactor. The oligomerization reactor is a fixed-bed tubular catalytic reactor system operated as a trickle bed. Typically, this reactor is oriented vertically. Inert materials such as alumina balls or a static mixer may be used at the inlet of the reactor to help evenly distribute the liquid raw material across the catalyst bed. The n-1-alkenes in the LFP liquid product are oligomerized in the oligomerization reactor to form longer-chain hydrocarbons. At least some of the n-hydroxyalkanes in the LFP liquid product are also converted in the oligomerization reactor. The oligomerization reactor produces a mixture of high molecular weight hydrocarbons. Subsequently, the oligomerized product is separated into several products in a separation unit. In this invention, the olefins in the LFP liquid product are oligomerized to form a lubricant having a boiling point of 343-510°C (650-950°F).

[0054] Many possible oligomerization catalysts exist that can be used in the present invention. In one embodiment of the present invention, the catalyst is chromium impregnated on a silica substrate. The catalyst has 0.5 to 5.0 wt% chromium, with a preferred chromium load as part of the total catalyst weight being about 1.0 wt%. The silica support is composed of highly porous silica gel. The catalyst is calcined in air at 800°C for 16 hours. The catalyst can be reduced in various ways before use in an oligomerization reactor, and the catalyst can be reduced with CO at 300°C for 1.5 hours. The catalyst may also be reduced with synthesis gas. Other possible catalysts include Ziegler-Natta catalysts or metallocene catalysts, as well as ZSM-5 and other silica-alumina materials.

[0055] The oligomerization reaction is an exothermic reaction. The operating temperature of this reactor is 120-160°C. Since the viscosity of the lubricating base oil decreases as the reaction temperature increases, this high reaction temperature can be used as a means of controlling the viscosity of the lubricant. Low pressures, such as atmospheric pressure, can also be used, but the operating pressure is preferably 18.2-24.5 bar (250-350 psig).

[0056] Approximately 70%, over 80%, and more preferably over 90% of the olefins in the LFP liquid product are converted into lubricants in a single pass. Some of the hydroxyalkanes in the LFP liquid product are also converted into lubricants.

[0057] The oligomerized LPF liquid product contains only small amounts of olefins or oxygenates, and in some embodiments, it is composed mainly of paraffins. Therefore, separating the oligomerized product to obtain specific normal paraffins is much easier than separating normal paraffins from untreated LPF liquid products, because the co-elution of normal 1-alkenes and normal hydroxyalkanes is less likely.

[0058] In one embodiment, the oligomerized LFP product is further processed in a reforming unit. The reforming unit converts the oligomerized LFP liquid product into synthesis gas. The reforming unit uses steam to convert the oligomerized LFP liquid product into synthesis gas. This synthesis gas can be used as part of the LFP reactor feedstock.

[0059] When this LFP catalyst is used to convert synthesis gas at a ratio of approximately 2.0 H2 / CO, a temperature of approximately 410°F, and a pressure of approximately 325 psi, the LFP liquid product consists mainly of linear paraffins (Table 2). In some embodiments, oligomerization reactions yield oligomerized products with several branches. This improves the low-temperature fluidity characteristics of the diesel fraction.

[0060] Another fraction of the oligomerized product consists of lubricants. These lubricants are typically composed of mixtures of hydrocarbons with boiling points above 343°C (650°F). These lubricants are similar in properties to poly-α-olefins (PAOs) with high viscosity index (VI). Viscosity index is a measure of the temperature dependence of the kinematic viscosity of a lubricant and is generally measured by the method defined in ASTM D2270. A higher VI indicates lower temperature dependence of viscosity and better lubricant performance. The VI of a lubricant should be at least 95. Kinematic viscosity can be measured by a viscometer using the method of ASTM D445. The kinematic viscosity of these lubricants at 100°C should be at least 3.0 mm per second. 2 It should be that way.

[0061] To obtain a fraction with a specific kinematic viscosity, additional separation by distillation of the lubricant may be desired. For example, a viscosity index of 95 and a flow rate of 4.5 mm per second. 2A lubricant having a kinematic viscosity at 100°C can be separated into two fractions in a distillation column: a light lubricant and a heavy lubricant. The light lubricant has a boiling point range of 343–427°C (650–800°F), while the heavy lubricant has a boiling point range of 427–593°C (800–1100°F). The light lubricant is distilled at a rate of approximately 3 mm per second. 2 It has a kinematic viscosity of 95 at 100°C. The heavy lubricant is approximately 7 mm 2 It has a kinematic viscosity of / second at 100°C. [Examples]

[0062] Several exemplary embodiments, which provide details of some of the embodiments described in this document, are included below.

[0063] Example 1 - Distillation of LFP liquid product Using the following catalytic operating conditions, approximately 900 gallons of LFP liquid product were produced from synthesis gas with an H2 / CO ratio of 1.08: T: 415°F, P: 315 psi, SV: 1,750. From this LFP liquid product, n-alkanes, n-1-alkenes, and n-1-hydroxyalkanes were separated using a two-stage high-efficiency distillation process. The first distillation process used a 12-inch distillation column packed with 35-foot Goodloe Style 779 style vertical stainless steel packing. This first distillation system was used to produce approximately 20 fine fractions from 700 gallons of LFP liquid product. Each of these fractions was then separated into individual components using a second 35-foot high-efficiency distillation system. The results of this two-stage separation process are summarized in Table 5. The separated n-alkanes, n-1-alkenes, and n-1-hydroxyalkanes account for 71.5%, 17.4%, and 4.8% by volume, respectively, of the total liquid product. Figure 2 provides a schematic overview of the products separated from this process.

[0064] [Table 5]

[0065] Example 2 - Composition and commercial use of wax fraction The synthetic wax product obtained by the LFP conversion process is mainly C 18 -C 45 It is composed of normal aliphatic hydrocarbons within the specified range (Table 6). This wax contains almost no cyclic, aromatic, or sulfur compounds (<1 ppm), and the concentration of olefins is very low (<25 ppm).

[0066] This wax has a macrocrystalline structure in which crystals are visible even without magnification. This wax melts in the same range as petroleum-derived paraffins, 115–145°F (Table 6). However, petroleum-derived paraffins contain branched hydrocarbons (isoalkanes), cyclic compounds, and aromatic compounds, typically exceeding 25% by weight. In contrast, this LFP wax contains less than 2% by volume of branched (iso)paraffins and does not contain cyclic or aromatic compounds. Furthermore, since isoalkanes are more easily oxidized than normal alkanes, this LFP wax also exhibits improved oxidation stability.

[0067] Sasol and Shell waxes are C 18 -C 100 Composed of hydrocarbons, the untreated wax has a melting point of 115–230°F. Therefore, Sasol waxes and Shell waxes need to be fractionated into light, medium, and heavy fractions before being brought to market.

[0068] [Table 6]

[0069] This LFP process-synthesized wax is expected to be an ideal material for the following applications: 1. As a rubber additive to prevent cracking. 2. For waxing skis and snowboards. 3. For protecting painted furniture, cabinets, and walls, and for achieving a matte finish. 4. As a release agent for metal castings. 5. For preventing oxidation of steel and iron surfaces. 6. For waterproofing leather.

[0070] US Patent Documents 7,507,326 B1 03 / 2009 Farshid et al. 8,394,862 B1 03 / 2013 Schuetzle et al. 8,974,660 B1 03 / 2015 Tanaka et al 9,611,145 B1 04 / 2017 Schuetzle et al. 9,631,147 B1 04 / 2017 Schuetzle et al. 9,896,626 B1 02 / 2018 Schuetzle et al. 10,478,806 B1 11 / 2019 Schuetzle et al.

[0071] Foreign Patent Documents CA 2,936,903 03 / 2018 Schuetzle et al CA 2,904,242 12 / 2017 Schuetzle et al. CA 2,948,235 08 / 2018 Schuetzle et al

[0072] Other publications Ail, SS, Dasappa, S.: Renewable and Sustainable Energy Reviews 58 267-286 (2016) De Klerk, A.: Fischer-Tropsch Refining, University of Pretoria, South Africa (2008) Fedou at al: Conversion of syngas to diesel, Axens, www.axens.net (2020) Gruber, H. et al: Fischer-Tropsch products from biomass-derived syngas and renewable hydrogen, Biomass Conversion and Biorefinery (2019) Li, W., Wang, H., Jiang, X., Zhu, J., Liu, Z., Guo, X., Song, C.: A short review of recent advances in CO2hydrogenation to hydrocarbons over heterogeneous catalysts, RSC Adv., 8, 7651 (2018) Schuetzle, D., Tamblyn, G., Caldwell, M., Schuetzle, R.: Solar reforming of carbon dioxide to produce diesel fuel. DOE report #DE-FE0002558 (2010) Zhu, Q.: Developments on CO2Utilization technologies, Clean Energy, 3, 85-100 (2019)

Claims

1. A method for producing a chemical substance, wherein the method is A step comprising supplying a feedstock containing hydrogen and carbon monoxide to a liquid fuel production reactor, wherein the liquid fuel production reactor contains a catalyst and thereby produces a product, the product comprising a liquid phase and a solid phase, and the liquid phase being C ５ -C ２３ A hydrocarbon and an oxygenated hydrocarbon, wherein the solid phase is C ２４ -C ４５ The step includes a step comprising an aliphatic hydrocarbon, wherein the liquid phase constitutes 75% by volume or more of the product, The step of distilling the liquid phase into three fractions, wherein the three fractions are C ５ -C ９ a naphtha fraction containing hydrocarbons and oxygenated hydrocarbons, C ９ -C ２３ a diesel fuel fraction containing hydrocarbons and oxygenated hydrocarbons, C ２４ -C ４５ a solid phase fraction containing hydrocarbons, and further comprising the step The process further includes the step of hydrogen isomerizing the diesel fuel fraction, The volume / volume ratio of hydrogen to carbon monoxide supplied to the liquid fuel production reactor is in the range of 0.5 to 1.

08. The method wherein the solid phase is composed of an alkane and contains less than 2% by volume of isoalkane.

2. The method according to claim 1, wherein the liquid phase contains 95% or more by volume of the product, and the solid phase contains 5% or less by volume of the product.

3. C in the liquid phase ５ -C １６ The concentration of n-1-alkenes depends on the ratio of hydrogen to carbon monoxide supplied to the liquid fuel production reactor, and as this ratio decreases, C ５ -C １６ The method according to claim 1, wherein the amount of normal 1-alkene is increased.

4. C in the solid phase ２４ -C ４５ The concentration of normal aliphatic hydrocarbons depends on the ratio of hydrogen to carbon monoxide supplied to the liquid fuel production reactor, and as this ratio decreases, C ２４ -C ４５ The method according to claim 1, wherein the amount of normal aliphatic hydrocarbons is increased.

5. The method according to claim 1, wherein the hydrogen supplied to the liquid fuel generation reactor is produced by electrolyzing water using renewable electricity.

6. The method according to claim 1, wherein the hydrogen and carbon monoxide supplied to the liquid fuel production reactor are produced from catalytic conversion of hydrogen and carbon dioxide, and the hydrogen is produced by electrolyzing water using renewable electricity.

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