Simultaneous dehydration, dimerization and metathesis of c2-C5 alcohols

Abstract

The present disclosure relates to a single stage process for the direct conversion of an alcohol, such as ethanol, to an olefin mixture with low levels of aromatics (C2-C7), carried out in a single reactor with two fixed catalyst beds in series or two catalytic fixed bed reactors in series, wherein the first reactor is operated at a temperature lower or higher than the operating temperature of the second reactor. Process transitions of ethanol include dehydrating ethanol to ethylene and water in a high yield with a first catalyst or through a first fixed catalyst bed in a first reactor, followed by feeding ethylene and water directly to a second reactor, or a second fixed catalyst bed, the ethylene and water are converted to a C2-C7 olefin mixture with a second catalyst in high yields and with minimal formation of aromatic compounds.

Description

[0001] This application is an application filed on September 29, 2020 and is entitled “C 2 -C 5 This is a divisional application for invention patent application No. 202080068569.5 for "simultaneous dehydration, dimerization and metathesis of alcohols".

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the prior art filing entitled “Simultaneous Dehydration, Dimerization, Metathesis, and Oligomerization of C 2 -C 5 Alcohols(C 2 -C 5 No. 62 / 908,457, filed on October 4, 2019, entitled “Simultaneous Dehydration, Dimerization, Metathesis, and Oligomerization of C 2 -C 5 Alcohols(C 2 -C 5 No. 62 / 910,948, filed on October 14, 2019, entitled “Simultaneous Dehydration, Dimerization, Metathesis, and Oligomerization of C 2 -C 5 and U.S. Provisional Patent Application Serial No. 62 / 914,837, filed on November 20, 2019, entitled “Simultaneous Dehydration, Dimerization, Metathesis, and Oligomerization of C 2 -C 5 Alcohols(C 2 -C 5 62 / 938,172 entitled "Simultaneous Dehydration, Dimerization, Metathesis and Oligomerization of Alcohols"; each of which is hereby incorporated by reference in its entirety for all purposes. Technical Field

[0004] The subject matter described herein relates to methods for converting one or more C 2 -C 5 Conversion of linear or branched alcohols into C 2 -C 7 One or more C 2 -C 5 The alcohol can come from a bio-based process. The process can be carried out with two reactors in series or in one reactor with two catalyst beds. 2 -C 7 The olefins are suitable for oligomerization and conversion into gasoline, jet fuel and / or diesel fuel. Background Art

[0005] There is an increasing need to use biomass sources as a starting point for synthetic fuels instead of petroleum. Therefore, the use of alcohols derived from biomass as base stocks for synthetic fuels has attracted great interest. The reactions used to convert alcohols into base stocks for fuels usually start with dehydration followed by olefin oligomerization. 2 -C 5 Alcohols are traditionally dehydrated in a unit operation in the presence of a dehydration catalyst at 300°C to 500°C to produce C 2 -C 5 Olefins and water. The water is removed and the C 2 -C 5 Olefins are further processed / purified to remove unreacted C 2 -C 5 Alcohol and / or impurities. Relative to ethanol (C 2 Conventional methods for converting C to chemicals and / or fuels utilize discrete unit operations to accomplish i) dehydration to ethylene, ii) ethylene purification followed by dimerization to butenes, iii) metathesis to propylene, iv) butene oligomerization to unsaturated jet fuel and / or diesel fuel precursors, or v) ethylene direct oligomerization to unsaturated jet fuel and / or diesel fuel precursors. 4 or C 5 The process for converting alcohols into chemicals and / or fuels utilizes discrete unit operations to accomplish i) dehydration to C 4 or C 5 olefins, ii) olefin purification to remove oxygenates and / or unreacted alcohols, and iii) oligomerization to unsaturated jet and / or diesel fuel precursors. As described below, efforts have been made to convert alcohols into fuel feedstocks.

[0006] International Patent Application WO 2010 / 097175 A1 relates to the direct conversion of oxygen-containing compounds into liquid hydrocarbons with a low aromatic content. The method can be carried out by a two-stage process, in which the first and second reactors are in series, and both reactors use zeolite catalysts. The single-pass conversion rate of methanol is usually >95%, and the reported final liquid product mainly consists of 60% to 85% of C with n≥5 n olefins, 15% to 40% by weight of light C with n = 2-4 n olefins, and <10% aromatics. The final liquid product is hydrogenated to obtain a gasoline fraction or oligomerized according to a conventional method to obtain a mixture of gasoline, kerosene, and diesel. However, these examples describe methanol, which is more toxic than ethanol, and no examples using ethanol as a raw material are given. In addition, the main product is high-carbon olefins (n>5), rather than light-carbon (2<n<4) olefins, which may be the result of using zeolite-type catalysts in both reactors.

[0007] U.S. Patent No. 8,552,241 relates to a method for converting ethanol into diesel base stock in a single step, which includes contacting ethanol with an acid catalyst at a reaction temperature of 300°C to 500°C. The catalyst used is a 50 / 50 mixture of γ-alumina and the commercial Axens catalyst "IS463 type" sold as an alumina-based catalyst for skeletal isomerization of C 4 and C 5 olefin fractions. Only one reactor and only one type of catalyst are used. The typical single-pass product distribution consists of 40% to 50% of a hydrocarbon fraction and 5% to 20% yield of an organic liquid phase. The organic liquid phase consists of approximately 50% olefins, in which C 6 olefins are in the majority, and approximately 40% has a boiling point above 150°C and is thus compatible with the diesel pool. The 40% to 50% hydrocarbon gas phase mainly contains ethylene and ethane and traces of C 1 、C 3 、C 4 and C 5 。 In this case, the yield of the organic liquid phase is relatively low, and approximately 20% has a boiling point above 150°C. The other 80% of the organic liquid and hydrocarbon fraction mainly consists of ethylene and ethane and traces of C 1 、C 3 、C 4 、C 5 and C 6 olefins. Therefore, the described method is not effective or economical.

[0008] U.S. Patent No. 9,840,676 relates to a process for converting ethanol into a fuel that can be used as a full-performance or military jet fuel or diesel fuel in a three-step process. The process begins with ethylene formation, followed by trimerization to form hexene, and finally oligomerization to form a jet fraction and a diesel fraction. The multi-stage process converts ethanol into light olefins, such as C 2 -C 4 Olefins then need to be further oligomerized to produce fuels such as gasoline and diesel. The catalyst used for the trimerization of ethylene to hexene is a Ziegler Natta catalyst.

[0009] In conventional ethanol dehydration processes, ethanol conversion is almost complete. Increasing C while maintaining high ethanol conversion 2 Selectivity is very important to improve process efficiency and save expensive steps of downstream separation / purification. The reaction products are then mainly water and ethylene. Ethylene selectivity as high as 96% is obtained. Subsequent ethylene oligomerization requires high gauge pressures, typically 2 MPa to 4 MPa, but requires lower temperatures, typically 20°C to 200°C. However, direct oligomerization of ethylene leads to C 10+ or diesel fractions are relatively low (about 40% of the highest reported level). Summary of the invention

[0010] Aspects of the present subject matter particularly relate to methods for converting C 2 -C 5 Alcohols are converted to C 2 -C 7 Olefin method.

[0011] Consistent with some aspects of the current subject matter, disclosed are methods for converting one or more C 2 -C 5 Conversion of linear or branched alcohols into one or more C 2 -C 7 A process for the production of olefins. The process comprises two different catalyst systems using either two reactors in series, each reactor having one catalyst, or one reactor having two catalyst beds. For the process using two reactors in series, the water product from the first reactor can be separated from the stream before entering the second reactor, or remain in the stream.

[0012] In variations, one or more of the following features may be included in any feasible combination. For example, one or more C 2 -C 5 The linear or branched alcohol may be C 2 -C 4 Linear or branched alcohols. One or more C 2 -C 7 The olefin can be C 2 -C6 In addition, one or more C 2 -C 7 The mass yield of olefins may be between 70% and 99%.

[0013] The temperature, pressure and WHSV of the process occurring in the two reactors in series may be different or the same between the two reactors. For example, the temperature of the first reactor may be from 300°C to 450°C, including all subranges therebetween, and the temperature of the second reactor may be from 320°C to 450°C, including all subranges therebetween. The gauge pressure of the first reactor and the second reactor may independently be from 0 to 10 bar, including all subranges therebetween. The WHSV of the first reactor and the second reactor may each independently be from 0.5 to 10 and all subranges therebetween.

[0014] In a process occurring in a reactor having two catalyst beds, the temperature, pressure, and WHSV are consistent as the feed stream flows from the first catalyst bed to the second catalyst bed. The temperature of a reactor process may be from 300°C to 400°C, including all subranges therebetween. The pressure may be from 0 to 10 bar, including all subranges therebetween. The WHSV may be from 0.5 to 10 and all subranges therebetween.

[0015] Regardless of whether the reaction is carried out in one or two reactors, the methods described herein include two catalyst systems. The first catalyst comprises a γ-alumina catalyst, which may contain Zr. The first catalyst may not contain a zeolite catalyst. The second catalyst comprises a zeolite catalyst, which contains boron, phosphorus, or both. The second catalyst may also comprise a γ-alumina catalyst, W-SiO 2 The catalyst or W-Zr catalyst, wherein the gamma-alumina optionally includes Zr, W or Mo.

[0016] It should be understood that all combinations of the foregoing concepts and the additional concepts discussed in more detail below (assuming these concepts are not mutually inconsistent) are considered part of the inventive subject matter disclosed herein. In particular, all combinations of the claimed subject matter of the present disclosure are considered part of the inventive subject matter disclosed herein. It should also be understood that the terms explicitly adopted herein, which may also appear in any disclosure incorporated by reference, should be given the meaning most consistent with the specific concepts disclosed herein. Specific implementation plan

[0017] In the following description, certain specific details are set forth to provide a thorough understanding of various embodiments. However, those skilled in the art will appreciate that the present disclosure may be implemented without these details. In other cases, well-known structures are not shown or described in detail to avoid unnecessarily obscuring the description of the examples. Unless the context otherwise requires, throughout this specification and the appended claims, the words "include / comprise" and their variations, such as "include" and "include", will be interpreted as open-ended inclusion / inclusion meanings, i.e., as "include / includes but is not limited to". In addition, the titles provided herein are for convenience only and do not explain the scope or meaning of the disclosure claimed for protection.

[0018] Reference to "one embodiment" throughout this specification means that the specific features, structures or characteristics described in connection with the embodiment are included in at least one embodiment. Therefore, the phrase "in one embodiment" that appears in many places throughout this specification does not necessarily all refer to the same embodiment. In addition, specific features, structures or characteristics can be combined in any suitable manner in one or more embodiments. In addition, as used in this specification and the appended claims, nouns that are not modified by quantifiers include one / kind and / or more / kinds unless the context clearly provides otherwise. It should also be noted that, unless the context clearly provides otherwise, the term "or" is generally used to include the meaning of "and / or".

[0019] When immediately preceding a numerical value, the word "about" means a range of plus or minus 10% of that value, e.g., "about 50" means 45 to 55, "about 25,000" means 22,500 to 27,500, etc. Additionally, the phrase "less than about" a value or "greater than about" a value should be understood in view of the definition of the term "about" provided herein.

[0020] "Oxygenate" refers to a compound that contains oxygen in its chemical structure. Examples of oxygenates include, but are not limited to, water, alcohols, esters, and ethers.

[0021] "WHSV" refers to weight hourly space velocity and is defined as the weight of feed flow per unit weight of catalyst per hour.

[0022] "Single-stage conversion" refers to a process that occurs within a single reactor system.

[0023] Unless otherwise stated, all yields and conversions reported herein are on a mass basis.

[0024] Described herein is a method for converting alcohols in a single-stage reactor with dual catalysts or in a two-stage reactor configuration (in series) with separate catalyst beds. 3 -C 7The methods provide a way to convert alcohols such as ethanol into an economical method for converting base oils for the production of fuels. In addition, the methods described herein can be carried out at a lower pressure and a higher temperature with a higher olefin yield than previously reported. The methods include converting a water-containing bioalcohol feedstock derived from biomass into a higher molecular weight olefin mixture in a single stage, which can be easily oligomerized into C 10+ hydrocarbon or diesel fractions. The single-stage reactor or two-stage reactor configuration uses a specific catalytic system that minimizes the production of aromatic compounds and maximizes the production of middle distillates. This is both an asset and a lasting advantage for ethanol refineries. The method described herein converts C 2 -C 5 The alcohol is efficiently and economically converted into fuel base oil. 2 -C 5 The alcohol is converted into the desired fuel product precursor (i.e., C 3 -C 7 Olefins) reduce processing costs.

[0025] Since the temperature required for complete dehydration is higher (300°C to 500°C) and a large amount of water is present, it is not possible to simultaneously dehydrate C 2 -C 5 Dehydration / dimerization / metathesis of alcohols is challenging. Implementing a single unit operation capable of simultaneously dehydrating, dimerizing, and metathesizing alcohols requires the use of catalysts that can withstand high temperatures and large amounts of water and other oxygenates. The ability to complete a large number of unit operations and chemical transformations in a single stage provides favorable economics due to reduced fixed and variable costs, lower capital investments, and increased productivity.

[0026] Aspects of the present subject matter provide a method for converting C to N-2 in high yield and at low aromatic levels at a competitive cost using a dual catalyst system. 2 -C 5 Conversion of linear or branched alcohols into C 2 -C 7 Olefins approach to overcome challenges. 2 -C 7 Olefins can be easily oligomerized into base stocks for producing fuels in high yields. The process can be carried out in two catalytic fixed bed reactors in series, wherein the first reactor is operated at a lower or higher temperature than the operating temperature of the second reactor. The process comprises the steps of: dehydrating alcohols to lower carbon chain olefins and water in high yield using a first catalyst in the first reactor, subsequently feeding the lower carbon chain olefins and water directly into the second reactor, and converting the lower carbon chain olefins and water into C 2 -C7 In addition, in a two-stage process, the water formed during the dehydration of the alcohol in the first reactor with the first catalyst can be separated from the lower carbon chain olefins after leaving the first reactor and before being fed to the second reactor containing the second catalyst. Alternatively, alcohols such as ethanol can be converted into a mixture of olefins (C 2 -C 7 ), wherein the first catalyst is located at the top of the reactor and the second catalyst is located in the portion of the reactor below the first catalyst. In a two-stage or single-stage process, depending on the oligomerization catalyst selected, the resulting C 2 -C 7 Olefin mixtures are suitable for oligomerization at relatively low temperatures and pressures into gasoline, jet fuel or diesel fuel fractions.

[0027] One advantage of having two catalyst beds in two reactors in series rather than in one reactor is the ability and flexibility it allows to operate the reactors at two different reaction temperatures. In this process, the effluent from the first dehydration reactor is directed "as is" to the second reactor in series with water vapor and other minor impurities at an optimal temperature depending on the target fuel and / or olefin mixture. For example, in the first reactor (fixed bed "A"), ethanol is dehydrated to ethylene over siliconized, zirconized, titanated, niobium or fluorinated gamma-alumina at 360°C, and the gaseous non-condensed ethylene-rich stream containing water and impurities is subsequently directed to the second reactor (fixed bed "B") filled with ethylene dimerization and metathesis to C in high yield. 3 -C 7 Olefins: i) metathesis catalyst (i.e. tungstate alumina, etc.) mixed with ZSM-5 zeolite or doped ZSM-5 zeolite, or ii) doped ZSM-5 zeolite mixed with zirconated alumina catalyst at internal temperature of 300°C to 500°C and pressure of 0 to 30 bar and WHSV 0.5-10. This two-reactor cascade approach enables practitioners to independently optimize reactor temperatures and allows catalyst regeneration in the second reactor (fixed bed "B") without interrupting operation of the first reactor (fixed bed "A").

[0028] Disclosed herein are methods for converting one or more C 2 -C 5 Linear or branched alcohols are converted into one or more C 2 -C 7 A method for producing olefins, the method comprising: 2 -C 5A first stream of a linear or branched alcohol is contacted with a first catalyst in a first reactor at a temperature of 200° C. to 500° C., a gauge pressure of 0 to 30 bar, and a WHSV of at least 0.5 to form a second stream, wherein the first catalyst comprises an alumina catalyst comprising one or more of Si, Zr, Ti, Nb, W, or F in neutral or ionic form; and the second stream is contacted with a second catalyst in a second reactor at a temperature of 200° C. to 500° C., a gauge pressure of 0 to 30 bar, and a WHSV of at least 0.5, wherein the second catalyst comprises a doped or undoped zeolite catalyst and / or a doped or undoped W-Zr catalyst, and the one or more C-Zr catalysts are formed in a mass yield of at least 65%. 2 -C 7 Olefins.

[0029] Another dual-reactor scheme can be beneficial for converting ethanol to C with high yields. 3 -C 7 For example, in a first reactor (fixed bed "A"), ethanol is dehydrated to ethylene over siliconized, zirconated, titanated, niobium or fluorinated gamma-alumina at 360°C, followed by removal of water and directing the gaseous non-condensable ethylene-rich stream saturated with water to a second reactor (fixed bed "B") filled with ethylene dimerization and metathesis to C in high yield. 3 -C 7 Olefins: i) a metathesis catalyst (i.e., tungstate alumina, etc.) mixed with a ZSM-5 zeolite or a doped ZSM-5 zeolite, or ii) a doped ZSM-5 zeolite mixed with a zirconated alumina catalyst at an internal temperature of 300°C to 500°C and a pressure of 0 to 30 bar and a WHSV of 0.5-10. This two-reactor cascade approach enables practitioners to independently optimize reactor temperatures and allow for catalyst regeneration in the second reactor (fixed bed "B") without interrupting operation of the first reactor (fixed bed "A"), and enables the use of catalyst combinations that exhibit lower stability to the presence of large amounts of water.

[0030] The present disclosure also provides methods for converting one or more C 2 -C 5 Conversion of linear or branched alcohols into one or more C 2 -C 7 A method for producing olefins, the method comprising: 2 -C 5A first stream of a linear or branched alcohol is contacted with a first catalyst in a first reactor at a temperature of 200° C. to 500° C., a gauge pressure of 0 to 30 bar, and a WHSV of at least 0.5 to form a second stream, wherein the first catalyst comprises an alumina catalyst comprising one or more of Si, Zr, Ti, Nb, W, or F in neutral or ionic form; a portion of water is separated from the second stream; and the second stream is contacted with a second catalyst in a second reactor at a temperature of 200° C. to 500° C., a gauge pressure of 0 to 30 bar, and a WHSV of at least 0.5, wherein the second reactor comprises a doped or undoped zeolite catalyst and / or a doped or undoped W-Zr catalyst, and the one or more C-Zr catalysts are formed in a mass yield of at least 70%. 2 -C 7 Olefins.

[0031] A single unit operation (i.e., a single reactor) can also be used to convert lower alcohols in high yields into viable feedstocks of higher molecular weight olefins that can be readily oligomerized into fuel base stocks in high yields. For example, passing a vaporized stream of undenatured fuel grade (>92.1% v / v ethanol / water) or aqueous ethanol through a fixed catalyst bed "A" comprising siliconized, zirconized, titanated, niobium or fluorinated gamma-alumina at 300°C to 400°C at 0 to 30 bar gauge pressure and 0.5 to 10 WHSV, followed by passing an ethylene vapor stream directly over a fixed catalyst bed "B" comprising the following in the same reactor at the same temperature and gauge pressure (i.e., 300°C to 400°C, 0 to 30 bar) without separation, purification or removal of water, can provide ethanol producers with C in high yield and minimal aromatic content. 3 -C 7 Olefin mixture; C 3 -C 7 The olefin mixture can be separated and sold, or after removal of condensed water, oligomerized "as is" to primary jet fuel and / or diesel fuel in high yields.

[0032] The present disclosure also describes methods for converting one or more C 2 -C 5 Conversion of linear or branched alcohols into one or more C 2 -C 7 A method for producing olefins, the method comprising: 2 -C 5A first stream of a linear or branched alcohol is contacted with a first catalyst bed in a reactor at a temperature of 200° C. to 500° C., a gauge pressure of 0 to 30 bar and a WHSV of at least 0.5 to form a second stream, wherein the first catalyst bed comprises an alumina catalyst comprising one or more of Si, Zr, Ti, Nb, W or F in neutral or ionic form; and the second stream is contacted with a second catalyst bed in the reactor at the same temperature, pressure and WHSV as the first reactor, wherein the second catalyst bed comprises a doped or undoped zeolite catalyst and / or a doped or undoped W-Zr catalyst, and the one or more C-Zr catalysts are formed in a mass yield of at least 70%. 2 -C 7 Olefins.

[0033] C that can be used in the present disclosure 2 -C 5 Linear or branched alcohols include any C 2 -C 5 Linear or branched alcohols. For example, C 2 -C 5 The alcohol may be one or more of ethanol, propanol, isopropanol, 1-butanol, isobutanol, 2-butanol, tert-butanol, pentanol, 3-methyl-1-butanol, 2-methyl-1-butanol, 2,2-dimethyl-1-propanol, 3-pentanol, 2-pentanol, 3-methyl-2-butanol or 2-methyl-2-butanol. 2 -C 5 Alcohols can be derived from biologically based processes such as, but not limited to, fermentation. 2 -C 5 Linear or branched alcohols are bio-based and produced by a fermentation process. 2 -C 5 Linear or branched alcohols are not derived from petroleum.

[0034] Consistent with some aspects of the present subject matter, one or more C 2 -C 5 The linear or branched alcohol is ethanol, propanol, isopropanol, 1-butanol, isobutanol, 2-butanol or tert-butanol. In many cases, one or more C 2 -C 5 The linear or branched alcohol is ethanol, propanol, butanol or a combination thereof. For example, one or more C 2 -C 5 The linear or branched alcohol is ethanol. In another example, one or more C 2 -C 5 The linear or branched alcohol is isobutanol.

[0035] Consistent with some aspects of the present subject matter, one or more C of any of the methods described herein 2 -C 7 The olefin is any suitable olefin. In many cases, one or more C 2 -C 7 Olefins are one or more C 2 -C 6 In some examples, one or more C 2 -C 7 Including ethylene, propylene, butene, C 5 -C 6 Olefins or combinations thereof.

[0036] The temperature of the methods described herein can be any suitable reactor temperature known to those skilled in the art. In a method comprising two reactors, the temperature of the first reactor can be higher, lower, or the same as the second reactor. In some cases, the temperature of the first reactor is 300° C. to 450° C. In some instances, the temperature of the first reactor is 300° C. to 420° C. For example, the temperature of the first reactor is about 360° C.

[0037] In some examples, the temperature of the second reactor is 320° C. to 420° C. For example, the temperature of the second reactor is 340° C. to 400° C. In some examples, the temperature of the second reactor is 350° C. to 450° C. For example, the temperature of the second reactor is 380° C. to 410° C.

[0038] In a process comprising one reactor with two catalyst beds, the temperature of the reactor can be any suitable temperature. The temperature is from 300°C to 400°C. For example, the temperature is from about 330°C to 360°C.

[0039] The gauge pressure of the methods described herein can be any suitable gauge pressure known to those skilled in the art. In a method comprising two reactors, the gauge pressure of the first reactor can be higher, lower or the same as that of the second reactor. In some cases, the gauge pressure of the first reactor and the second reactor is each independently 0 to 30 bar. In some cases, the gauge pressure of the first reactor and the second reactor is each independently 0 to 10 bar. For example, the gauge pressure of the first reactor and the second reactor is each independently 0 to 1 bar. In some instances, the gauge pressure of the first reactor and the second reactor is each independently 0 bar.

[0040] The WHSV of the methods described herein can be any suitable WHSV known to those skilled in the art. In a method comprising two reactors, the WHSV is each independently at least 0.5. In many cases, the WHSV of the first reactor and the second reactor are each independently 0.5 to 10. For example, the WHSV of the first reactor and the second reactor are each independently 0.5 to 5. In some examples, the WHSV of the first reactor and the second reactor are each independently at least 1. In some instances, the WHSV of the first reactor and the second reactor is each about 2.1.

[0041] In a process comprising one reactor with two catalyst beds, the WHSV may be from 0.5 to 10. In some examples, the WHSV is at least 1. In some examples, the WHSV is from 2.1 to 2.3.

[0042] Even though no specific size and morphology is mandatory, pelletized or extruded catalysts are also suitable for the reaction. Catalysts with a size greater than 0.1 mm are more suitable, with a size of 0.4 mm to 1.0 mm being most suitable for operability and pressure drop.

[0043] Compared with standard commercial grade alumina catalysts, the first catalyst disclosed herein comprises an alumina catalyst containing Si, Zr, Ti, Nb, W or F (i.e., a doped alumina catalyst) and is more stable in the present method. Consistent with some aspects of the present subject matter, the first catalyst comprises an alumina catalyst comprising one or more of Si (silicon), Zr (zirconium), Ti (titanium), Nb (niobium), W (tungsten) or F (fluorine). One or more of Si, Zr, Ti, Nb, W or F can be in ionic form. In some cases, the alumina catalyst comprises Zr. Zr can be zirconium (IV). The first catalyst may not comprise a zeolite catalyst.

[0044] Zr may be present in the first catalyst in an amount of 2 wt % to 10 wt %. In some examples, Zr is present in the first catalyst in an amount of about 4.0 wt %. In other examples, Zr is present in the first catalyst in an amount of about 5.6 wt %.

[0045] The alumina catalyst can be regenerated as needed under conditions suitable for the methods described herein. Consistent with some aspects of the present subject matter, the alumina catalyst is regenerated in situ in air. The alumina catalyst can be regenerated at a temperature of 400° C. to 600° C. For example, the alumina catalyst can be regenerated at 500° C. Consistent with some aspects of the present subject matter, the alumina catalyst is regenerated for 30 minutes to 3 hours. For example, the alumina catalyst is regenerated for 1 hour to 2 hours.

[0046] The second catalyst may be for C 2 -C 5Combination of a "regenerable" catalyst for olefin conversion, consisting of a doped zeolite, for example a crystalline silicate of the group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON with a Si / Al higher than 10, or a dealuminated crystalline silicate of the group ZSM5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON with a Si / Al higher than 10, or a phosphorus and / or boron modified crystalline silicate of the group ZSM5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON with a Si / Al higher than 10, MTT or TON with a Si / Al higher than 10, or a molecular sieve of the silicoaluminophosphate type of the group AEL. The additional additive for mixing with the doped zeolite in the second catalyst consists of SiO 2 , MgO or double decomposition catalysts, i.e. tungstate or molybdenum-doped alumina, zirconia or SiO 2 Carrier composition.

[0047] The second catalyst includes a doped or undoped zeolite catalyst and / or a doped or undoped W-Zr catalyst. In many cases, the second catalyst is a doped or undoped zeolite catalyst. For example, the second catalyst can be a doped ZSM-5 zeolite catalyst. The doped ZSM-5 zeolite catalyst can contain boron, phosphorus, or both. For example, the doped ZSM-5 catalyst can contain boron and phosphorus. In another example, the doped ZSM-5 catalyst can contain boron. The second catalyst can also include a γ-alumina catalyst, a W-SiO 2 catalyst or a W-Zr catalyst, and wherein the γ-alumina optionally contains Zr, W or Mo.

[0048] Boron and phosphorus are present in an amount of 2% to 5% by weight of the second catalyst. In some cases, boron is present in an amount of about 2.5% by weight of the second catalyst, and phosphorus is present in an amount of about 3.7% by weight of the second catalyst. In some instances, boron is present in an amount of 2% to 5% by weight of the second catalyst. For example, boron is present in an amount of 3.5% to 4.1% by weight of the second catalyst.

[0049] In some cases, the second catalyst comprises an undoped ZSM-5 zeolite catalyst. The second catalyst comprising an undoped ZSM-5 zeolite catalyst may further comprise a Mo-Zr catalyst or a W-Zr catalyst.

[0050] The C formed by the method described herein 2 -C 7The mass yield of olefins is at least 65%. In many embodiments, the mass yield is at least 70%. 2 -C 7 The mass yield of olefins is 65% to 98%. For example, one or more C 2 -C 7 The mass yield of olefins is 75% to 95%. In some cases, one or more C 2 -C 7 The mass yield of olefins is 70% to 99%. In some examples, one or more C 2 -C 7 The mass yield of olefins is between 80% and 95%.

[0051] The present disclosure also provides a method for converting ethanol into one or more C 2 -C 7 A method for producing olefins, the method comprising: contacting a first stream comprising ethanol with a first catalyst in a first reactor at a temperature of about 360° C., a gauge pressure of 0 bar, and a WHSV of about 2.1 to form a second stream, wherein the first catalyst comprises a γ-alumina catalyst, and the γ-alumina catalyst comprises Zr; and contacting the second stream with a second catalyst in a second reactor at a temperature of 340° C. to 410° C., a gauge pressure of 0 bar, and a WHSV of about 2.1, wherein the second catalyst comprises a boron-doped ZSM-5 zeolite catalyst, wherein the doped zeolite catalyst comprises boron, phosphorus, or both, and forming the one or more C olefins in a mass yield of 80% to 95%. 2 -C 7 Olefins.

[0052] Also provided is a method for converting ethanol into one or more C 2 -C 7 A method for producing olefins, the method comprising: contacting a first stream comprising ethanol with a first catalyst in a first reactor at a temperature of about 360° C., a gauge pressure of about 0 bar, and a WHSV of about 2.1 to form a second stream, wherein the first catalyst comprises a γ-alumina catalyst, and the γ-alumina catalyst comprises Zr; separating a portion of water from the second stream; and contacting the second stream with a second catalyst in a second reactor at a temperature of 380° C. to 410° C., a gauge pressure of about 0 bar, and a WHSV of about 2.1, wherein the second reactor comprises a boron-doped ZSM-5 zeolite catalyst, and forming the one or more C olefins in a mass yield of 80% to 95%. 2 -C 7 Olefins.

[0053] The present disclosure also provides a method for converting ethanol into one or more C 2 -C 7A method for producing olefins, the method comprising: contacting a first stream comprising ethanol with a first catalyst in a reactor at a temperature of 330° C. to 360° C., a gauge pressure of about 0 bar, and a WHSV of 2.1 to 2.3 to form a second stream, wherein the first catalyst comprises a γ-alumina catalyst, and the γ-alumina catalyst comprises Zr; and contacting the second stream with a second catalyst in the reactor at the same temperature, pressure, and WHSV as the first reactor, wherein the second catalyst comprises an undoped ZSM-5 zeolite catalyst and a W-Zr catalyst or a Mo-Zr catalyst, and forming the one or more C olefins in a mass yield of 81% to 99%. 2 -C 7 Olefins.

[0054] Example

[0055] Reactor setup

[0056] Ethanol is converted to C 3 -C 7 Olefins Olefins are carried out by passing through a fixed bed reactor containing a specific catalyst at 300°C to 500°C and flowing preheated (160°C) evaporated ethanol in a downward stream over the fixed catalyst while co-feeding nitrogen at atmospheric pressure or moderate gauge pressure (i.e. 0 to 30 bar). The flow rate of ethanol is controlled by a Teledyne Model 500D syringe pump and the flow rate is adjusted to obtain the target olefin WHSV (weight hourly space velocity). The internal reaction temperature is kept constant by a Lindberg Blue M furnace manufactured by Thermo-Scientific. The liquid phase reactor effluent is analyzed by GC (gas chromatography) for organic and water content, as well as the relative concentration of uncondensed hydrocarbons (i.e. C 2 -C 7 The olefins) are analyzed online by GC to calculate the ethanol conversion and selectivity. Therefore, the vaporized stream of fuel-grade ethanol is passed through a silicified, zirconated, titanated or fluorinated alumina, followed by passing the hydrated ethylene through a second fixed bed catalyst at 350°C to 450°C, providing an ethanol refinery with a high yield of C 2 -C 7 ability.

[0057] The following representative examples involve the production of ethanol at >75% yield and lesser amounts of C via a single unit operation at >60% ethylene content and quantitative ethanol conversion. 5+ Olefins and aromatics (BTX - benzene, toluene, xylenes) convert fuel grade or aqueous ethanol primarily to propylene and butenes. Unreacted ethylene can be separated and recovered. Ethylene conversion can be increased by increasing the temperature in the second reactor, but in some cases, higher ethylene conversion leads to higher levels of aromatics, which is inconsistent with the C2O3 that can be converted into renewable diesel fuel.3 -C 7 The higher yield of olefins is more economically disadvantageous. On the contrary, the ethylene conversion rate may be reduced (about 40%), resulting in C 3 -C 7 Higher selectivity / yield of olefins (about 90%), reduced aromatics yield and higher ethylene recycle levels.

[0058] Catalyst Preparation Example 1a

[0059] Impregnated Zr-γ-alumina (nominal Zr metal 5 wt%) catalyst preparation: Zr-γ-alumina catalyst was prepared by the incipient wetness technique as described. Precursor metal salt (Sigma Aldrich): 2.64 grams of hydrated zirconium (IV) nitrate was dissolved in deionized water (14.9 ml). After the salt was dissolved, the solution was added to 15 grams of the γ-alumina support in a dropwise manner. The resulting mixed metal oxide was mixed manually to ensure complete wetting, and the resulting impregnated catalyst was dried at 160°C for 1 hour and then calcined at 500°C for 4 hours.

[0060] Catalyst Preparation Example 1b

[0061] Impregnated W-γ-alumina (nominal W metal 15 wt%) catalyst preparation: The W-γ-alumina catalyst was prepared by the incipient wetness technique as described. Precursor metal salt (Sigma Aldrich): 1.74 grams of ammonium tungstate pentahydrate was dissolved in deionized water (9.2 ml). After the salt was dissolved, the solution was added to 8 grams of the γ-alumina support in a dropwise manner. The poor solubility of the ammonium tungstate salt in water requires multiple water dissolutions and addition of the tungstate to the γ-alumina support to achieve the desired tungstate loading. After each addition of water / salt, the resulting mixed metal oxide was manually mixed to ensure complete wetting after each addition of tungstate, and the resulting impregnated catalyst was dried at 160°C for 1 hour and then calcined at 500°C for 4 hours.

[0062] Catalyst Preparation Example 1c

[0063] Impregnated boron and phosphorus impregnated ZSM-5 zeolite catalyst preparation: The boron and phosphorus impregnated zeolite catalyst was prepared by the incipient wetness technique as described. 0.83 g phosphoric acid (85%) and 0.94 g boric acid were dissolved in deionized water (7.2 ml). After dissolution, the solution was added dropwise to 6 g ZSM-5 zeolite support (i.e., Zeolyst type CBV-5524H + The resulting impregnated catalyst was dried at 160°C for 1 hour and then calcined at 550°C for 3 hours.

[0064] Example 2

[0065] No Two-stage reactor configuration for removing water from ethanol dehydration: reaction conditions: T = 360°C in the first reactor, T = 340°C in the second reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; catalyst - zirconated (5.6 wt. %) γ-alumina in the first reactor and boron / phosphorus doped ZSM-5 zeolite (2.5 wt. % boron / 3.7 wt. % phosphorus) mixed with Zr-alumina (5.6 wt. % Zr) in the second reactor.

[0066] Reactor effluent composition - wt % of total:

[0067]

[0068] Ethylene conversion is about 62%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 81%; the mass yield of aromatics based on ethylene conversion is about 8%.

[0069] Example 3

[0070] No Two-stage reactor configuration for removing water from ethanol dehydration: reaction conditions: T = 360°C in the first reactor, T = 370°C in the second reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; catalyst - zirconized (5.6 wt. %) γ-alumina in the first reactor and boron / phosphorus doped ZSM-5 zeolite (2.5 wt. % boron / 3.7 wt. % phosphorus) mixed with γ-alumina in the second reactor.

[0071] Reactor effluent composition - wt % of total:

[0072]

[0073] Ethylene conversion is about 70%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 76%; the mass yield of aromatic hydrocarbons based on ethylene conversion is about 10%.

[0074] Example 4

[0075] No Two-stage reactor configuration for removing water in ethanol dehydration: Reaction conditions: T = 360 °C in the first reactor, T = 380 °C in the second reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; Catalyst - zirconized (5.6 wt%) γ-alumina in the first reactor and mixed with W-SiO in the second reactor 2 (W about 15 wt%) of boron / phosphorus doped ZSM-5 zeolite (2.5 wt% boron / 3.7 wt% phosphorus).

[0076] Reactor effluent composition - wt % of total:

[0077]

[0078] Ethylene conversion is about 40%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 90%; the mass yield of aromatics based on ethylene conversion is about 4%.

[0079] Example 5

[0080] No Two-stage reactor configuration for removing water from ethanol dehydration: reaction conditions: T = 360°C in the first reactor, T = 395°C in the second reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; catalyst - zirconized (5.6 wt. %) γ-alumina in the first reactor and boron / phosphorus doped ZSM-5 zeolite (2.5 wt. % boron / 3.7 wt. % phosphorus) in the second reactor.

[0081] Reactor effluent composition - wt % of total:

[0082]

[0083]

[0084] Ethylene conversion is about 70%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 82%; the mass yield of aromatics based on ethylene conversion is about 8%.

[0085] Example 6

[0086] from Two-stage reactor configuration for removing water from ethanol dehydration: reaction conditions: T = 360 °C in the first reactor, T = 410 °C in the second reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; catalyst - zirconized (5.6 wt. %) γ-alumina in the first reactor and boron-doped ZSM-5 zeolite (4.1 wt. % boron) in the second reactor.

[0087] Reactor effluent composition - wt % of total:

[0088]

[0089] Ethylene conversion is about 55%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 85%; the mass yield of aromatics based on ethylene conversion is about 6%.

[0090] Example 7

[0091] from Two-stage reactor configuration for removing water from ethanol dehydration: reaction conditions: T = 360°C in the first reactor, T = 410°C in the second reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; catalyst - zirconized (5.6 wt%) γ-alumina in the first reactor and boron-doped ZSM-5 zeolite (3.7 wt% boron) mixed with W-zirconium (W about 15 wt%) in the second reactor.

[0092] Reactor effluent composition - wt % of total:

[0093]

[0094]

[0095] Ethylene conversion is about 60%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 88%; the mass yield of aromatics based on ethylene conversion is about 4%.

[0096] Example 8

[0097] from Two-stage reactor configuration for removing water from ethanol dehydration: reaction conditions: T = 360°C in the first reactor, T = 380°C in the second reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; catalyst - zirconized (5.6 wt. %) γ-alumina in the first reactor and boron-doped ZSM-5 zeolite (3.5 wt. % boron) mixed with Mo-alumina (W about 15 wt. %) in the second reactor.

[0098] Reactor effluent composition - wt % of total:

[0099]

[0100] Ethylene conversion is about 45%; based on ethylene conversion, C 3 -C 7 The mass yield of olefins is about 87%; the mass yield of aromatics based on ethylene conversion is about 2%.

[0101] Example 9

[0102] Single-stage reactor configuration: Reaction conditions: T = 355 °C in the reactor, WHSV = 2.1 (based on ethanol), P = 0 bar; Catalyst - zirconized (5.6 wt%) γ-alumina in the first catalyst bed and Mo-zirconium (Mo about 15 wt%) mixed with ZSM-5 zeolite in the second catalyst bed.

[0103] Reactor effluent composition - wt % of total:

[0104]

[0105] Ethylene conversion is about 60%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 75%; the mass yield of aromatics based on ethylene conversion is about 18%.

[0106] Example 10

[0107] Reaction conditions: T = 350 ° C, WHSV = 2.3, P = 0 bar; first catalyst bed - zirconated γ-alumina (2.9 g); second catalyst bed - zirconium tungsten (1.7 g) mixed with ZSM-5 zeolite (0.3 g); feed fuel grade ethanol (1% water).

[0108] Reactor effluent composition – wt %

[0109]

[0110]

[0111] Embodiment 11

[0112] Reaction conditions: T = 330 °C, WHSV = 2.3; first catalyst bed - zirconated γ-alumina (2.9 g); second catalyst bed - zirconium tungsten (1.7 g) mixed with ZSM-5 zeolite (0.3 g); feed fuel grade ethanol (1% water).

[0113] Reactor effluent composition – wt %

[0114]

[0115] Example 12

[0116] Two-stage reactor, wherein the first reactor contains the first catalyst: zirconated γ-alumina (2.9 grams); fuel-grade ethanol feed rate = 0.14 ml / min; T = 360°C; P = atmospheric pressure; the second reactor contains the second catalyst: boron-doped ZSM5 zeolite (2.5 grams); water inlet = 0.02 ml / min; T = 400°C; P = atmospheric pressure.

[0117] Reactor effluent composition - wt % of total:

[0118]

[0119] Prediction Example 13

[0120] NoTwo-stage reactor configuration for removing water from ethanol dehydration: Reaction conditions: T = 360 °C in the first reactor, T = 400 °C in the second reactor, WHSV = 2.1 (based on ethanol), P = 1 bar; Catalyst - zirconized (4 wt%) γ-alumina in the first reactor and mixed W-SiO 2 (W about 15 wt%) of boron / phosphorus doped ZSM-5 zeolite (4 wt% boron / 2 wt% phosphorus).

[0121] Reactor effluent composition - wt % of total:

[0122]

[0123] Ethylene conversion is about 50%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 92%; the mass yield of aromatics based on ethylene conversion is about 3%.

[0124] Prediction Example 14

[0125] Two-stage reactor configuration for removing water from ethanol dehydration: reaction conditions: T = 360°C in the first reactor, T = 370°C in the second reactor, WHSV = 2.1 (based on ethanol), P = 1 bar; catalyst - zirconized (4 wt%) γ-alumina in the first reactor and boron-doped ZSM-5 zeolite (4 wt% boron) mixed with W-zirconium (W about 15 wt%) in the second reactor. Reactor effluent composition - wt % of total:

[0126]

[0127] Ethylene conversion is about 65%; C based on ethylene conversion 3 -C 7 The mass yield of olefins is about 89%; the mass yield of aromatics based on ethylene conversion is about 4%.

[0128] Prediction Example 15

[0129] Single-stage reactor configuration: Reaction conditions: T = 355 °C in the reactor, WHSV = 2.1 (based on ethanol), P = 1 bar; Catalyst - zirconized (5.6 wt%) γ-alumina in the first catalyst bed and Mo-zirconium (Mo about 15 wt%) mixed with ZSM-5 zeolite in the second catalyst bed.

[0130] Reactor effluent composition - wt % of total:

[0131]

[0132] Ethylene conversion is about 60%; C based on ethylene conversion 3 -C 7The mass yield of olefins is about 80%; the mass yield of aromatics based on ethylene conversion is about 15%.

[0133] The following specific examples are intended to illustrate the present invention and should not be construed as limiting the scope of the present invention as defined by the appended claims.

[0134] The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, as modifications will be apparent to those skilled in the art.

[0135] While the invention has been described in conjunction with specific embodiments thereof, it will be understood that it is capable of further modifications, and this application is intended to cover any changes, uses or adaptations which follow generally from the principles of the invention and which include such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and which may be applied to the essential features as set forth above and within the scope given by the appended claims.

Claims

1. A method for converting one or more C2-C5 linear or branched alcohols into one or more C2-C7 olefins, the method comprising: contacting a first stream comprising the C2-C5 linear or branched alcohol with a first catalyst in a reactor at a temperature of about 200° C. to about 500° C., a gauge pressure of 0 to about 30 bar, and a weight hourly space velocity (WHSV) of at least 0.5 to form a second stream; and The second stream is contacted with a second catalyst in the reactor or in a different reactor operated at a temperature of about 200° C. to about 500° C., a gauge pressure of 0 to about 30 bar, and a weight hourly space velocity (WHSV) of at least 0.5, wherein the second catalyst comprises a doped zeolite catalyst comprising boron and phosphorus, thereby forming the one or more C2-C7 olefins.

2. The method of claim 1, wherein the first catalyst comprises an alumina catalyst.

3. The method according to claim 1 or 2, wherein the one or more C2-C5 linear or branched alcohols are ethanol, propanol, butanol or a combination thereof.

4. The method of claim 1 or 2, wherein the one or more C2-C5 linear or branched alcohols are bio-based and produced by a fermentation process.

5. The method of claim 1 or 2, wherein the one or more C2-C5 linear or branched alcohols are not derived from petroleum.

6. The method of claim 1 or 2, wherein the one or more C2-C7 olefins include ethylene, propylene, butene, C5-C6 olefins, one or more C2-C6 olefins, or a combination thereof.

7. The method of claim 1 or 2, wherein the first catalyst comprises a gamma-alumina catalyst.

8. The process of claim 1 or 2, wherein boron and phosphorus are each present in an amount less than 5 wt% of the second catalyst.

9. The process of claim 1 or 2, wherein boron and phosphorus are each present in an amount of 2 wt% to 5 wt% of the second catalyst.

10. A process for converting one or more C2-C5 linear or branched alcohols into one or more C2-C7 olefins, the process comprising: A stream comprising the C2-C5 linear or branched alcohol is contacted with at least two catalysts in a reactor at a temperature of about 200° C. to about 500° C., a gauge pressure of 0 to about 30 bar, and a weight hourly space velocity (WHSV) of at least 0.5 to form the one or more C2-C7 olefins, wherein one of the at least two catalysts comprises a doped zeolite catalyst comprising boron and phosphorus, and another of the at least two catalysts is different from the previous catalyst. The method of claim 10 , wherein the first catalyst comprises an alumina catalyst.

12. The process of claim 10 or 11, wherein boron and phosphorus are each present in an amount less than 5% by weight of the second catalyst.

13. The process of claim 10 or 11, wherein boron and phosphorus are each present in an amount of 2 wt% to 5 wt% of the second catalyst.

14. A method for preparing a catalyst, the method comprising: dissolving phosphoric acid and boric acid in deionized water to form a solution; adding the solution to a ZSM-5 zeolite support to form an impregnated catalyst; drying the impregnated catalyst; and The dried impregnated catalyst is calcined.

Images