Method for preparing mercaptan compounds using nickel-molybdenum catalysts

Abstract

A method for synthesizing a mercaptan compound includes contacting a nickel-molybdenum catalyst with H2S at a sulfiding temperature of 235°C or less to form a supported sulfur-containing catalyst, and then contacting an alcohol or olefin compound, H2S, and the supported sulfur-containing catalyst to form a reaction mixture comprising the mercaptan compound.

Description

[Technical Field]

[0001] This application was filed as an international patent application on October 5, 2021, and claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 088,494 (filed October 7, 2020), the disclosure of which is incorporated herein by reference in its entirety.

[0002] FIELD OF THE INVENTION The present disclosure relates to a process for producing mercaptan compounds from H2S and an alcohol or olefin reactant contacted in the presence of a supported sulfur-containing nickel-molybdenum catalyst. [Background technology]

[0003] Background of the Invention Mercaptan compounds (also referred to as thiol compounds) can be prepared by a variety of synthetic techniques, often in relatively low yields or with significant by-products. Thus, the present invention is generally directed to a catalytic process for producing mercaptan (or thiol) compounds in high yield and with minimal reaction by-products. Summary of the Invention

[0004] Summary of the Invention This Summary is provided to introduce some concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify required or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0005] Disclosed herein are methods for producing mercaptan compounds. In one embodiment, a first method for producing mercaptan (or thiol) compounds can include (i) contacting a nickel-molybdenum catalyst with HS at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst, and (ii) contacting an alcohol compound, HS, and the supported sulfur-containing catalyst to form a reaction mixture containing the mercaptan compounds. In another embodiment, a second method for producing mercaptan compounds can include (i) contacting a nickel-molybdenum catalyst with HS at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst, and (ii) contacting an olefin compound, HS, and the supported sulfur-containing catalyst to form a reaction mixture containing the mercaptan compounds.

[0006] Without limitation, the supported sulfur-containing catalyst can comprise a solid support, about 1 to about 5 wt.% nickel, about 4 to about 18 wt.% molybdenum, and about 3 to about 18 wt.% sulfur. Additionally, prior to step (ii), the supported sulfur-containing catalyst typically comprises about 3 wt.% or less carbon.

[0007] Both the foregoing summary and the following detailed description are exemplary and explanatory only. Accordingly, the foregoing summary and the following detailed description should not be considered limiting. Furthermore, various features and variations may be provided in addition to those described herein. For example, certain aspects may be directed to combinations and subcombinations of various features described in the detailed description.

[0008] definition In order to more clearly define the terms used herein, the following definitions are provided. Unless otherwise indicated, the following definitions are applicable to this disclosure. When a term is used within this disclosure and is not specifically defined herein, it is defined in accordance with the IUPAC Compendium of Chemical Terminology, 2nd Definitions from Ed (1997) may be applied, provided that they do not conflict with any other disclosure or definition applicable herein or render unclear or unenforceable any claim to which they apply. To the extent that any definition or usage set forth in any document incorporated by reference herein conflicts with a definition or usage set forth herein, the definition or usage set forth herein controls.

[0009] The subject features are described herein in such a way that combinations of different features can be envisioned within particular embodiments. For every embodiment and every feature disclosed herein, all combinations that do not adversely affect the compounds, compositions, processes, or methods described herein are contemplated, with or without the explicit description of a specific combination. Furthermore, unless expressly stated otherwise, any embodiment or feature disclosed herein can be combined to describe an inventive compound, composition, process, or method consistent with the present disclosure.

[0010] Generally, groups of elements are designated by the numbering scheme shown in the version of the Periodic Table of the Elements published in Chemical and Engineering News, 63(5), 27, 1985. In some cases, groups of elements may be designated using the common name assigned to the group, e.g., alkali metals for Group 1 elements, alkaline earth metals for Group 2 elements, transition metals for Groups 3-12 elements, and halogens or halides for Group 17 elements.

[0011] As used herein, a "mercaptan" or "mercaptan" compound is a compound having an -SH group, and is sometimes referred to herein as a "thiol" compound. The term "hydrocarbon" refers to a compound containing only carbon and hydrogen, whether saturated or unsaturated. Other identifiers may be used to indicate the presence of a particular group in a hydrocarbon (e.g., a halogenated hydrocarbon indicates the presence of one or more halogen atoms replacing an equivalent number of hydrogen atoms in the hydrocarbon). The term "hydrocarbyl group" is used herein according to the definition specified by IUPAC: a monovalent group formed by removing a hydrogen atom from a hydrocarbon (i.e., a group containing only carbon and hydrogen). Non-limiting examples of hydrocarbyl groups include alkyl, alkenyl, aryl, and aralkyl groups, among others.

[0012] For any particular compound or group disclosed herein, any given name or structure (generic or specific) is intended to encompass all conformational isomers, positional isomers, stereoisomers, and mixtures thereof that may arise from a particular set of substituents, unless otherwise specified. A given name or structure (generic or specific) also encompasses all enantiomers, diastereomers, and other optical isomers (if present), whether enantiomeric or racemic, that would be recognized by a person skilled in the art, as well as mixtures of stereoisomers, unless otherwise specified. For example, a general reference to pentane includes n-pentane, 2-methyl-butane, and 2,2-dimethylpropane, and a general reference to a butyl group includes n-butyl, sec-butyl, iso-butyl, and t-butyl groups.

[0013] Unless otherwise specified, the term "substituted," when used to describe a group, for example, when referring to a substituted analog of a particular group, is intended to represent any non-hydrogen moiety that formally replaces a hydrogen in the group and is intended to be open-ended. Unless otherwise specified, a group(s) may also be referred to herein as "unsubstituted," or equivalent terms such as "unsubstituted," which refer to the original group in which a non-hydrogen moiety does not replace a hydrogen in the group. Furthermore, unless otherwise specified, "substituted" is intended to be open-ended and include inorganic or organic substituents as would be understood by one of ordinary skill in the art.

[0014] As used herein, terms such as "contact product," "contacting," and the like, unless otherwise specified, are used to describe methods and compositions in which components are contacted together in any order, in any manner, and for any length of time. For example, components can be contacted by blending or mixing. Furthermore, unless otherwise specified, contacting of any component can occur in the presence or absence of any other component of the methods and compositions described herein. The combination of additional materials or components can be accomplished by any suitable method. Furthermore, the term "contact product" includes mixtures, blends, solutions, slurries, reaction products, and the like, or combinations thereof. While a "contact product" can, and often does, include a reaction product, it is not required that the respective components react with each other. Consequently, a "contact product" can be a mixture, a reaction mixture, or a reaction product, depending on the context. Similarly, "contacting" two or more components can result in a reaction product or a reaction mixture.

[0015] Although compositions and methods are described in this disclosure in terms of "comprising" various components or steps, the compositions and methods can also "consist essentially of" or "consist of" the various components or steps, unless otherwise specified.

[0016] The terms "a," "an," and "the" are intended to include plural alternatives, e.g., at least one. For example, disclosure of "a catalyst" is meant to encompass one catalyst, or a mixture or combination of catalysts, unless otherwise specified.

[0017] The present invention discloses several types of ranges. Whenever any type of range is disclosed or claimed, the intention is to separately disclose or claim each possible number that such range can reasonably encompass (including the endpoints of the range as well as subranges and combinations of subranges encompassed within the range). For example, when a chemical moiety having a certain number of carbon atoms is disclosed or claimed, the intention is to separately disclose or claim every possible number that such range can encompass, consistent with the disclosure herein. For example, when a moiety is disclosed or claimed as having a C1 to C 18 As used herein, a disclosure of an alkyl group, or alternatively, an alkyl group having 1 to 18 carbon atoms, refers to a moiety that can have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 carbon atoms, as well as any range between these two numbers (e.g., a C1-C8 alkyl group), and also any combination of ranges between these two numbers (e.g., C2-C4 and C 12 ~C 16 alkyl groups).

[0018] Similarly, other representative examples of HS:olefin molar ratios consistent with embodiments of the present invention are shown below. The disclosure that the molar ratio may be in the range of about 5:1 to about 20:1 is intended to illustrate that the molar ratio may be any ratio within that range, such as about 5:1, about 6:1, about 8:1, about 10:1, about 12:1, about 14:1, about 16:1, about 18:1, or about 20:1. Additionally, the molar ratio can be in any range from about 5:1 to about 20:1 (e.g., about 10:1 to about 15:1), including any combination of ranges between about 5:1 and about 20:1 (e.g., the ratio can be in the range of about 5:1 to about 10:1, or about 15:1 to about 20:1). Furthermore, in all cases, when a particular value preceded by "about" is disclosed, that value itself is disclosed. Thus, the disclosure of a molar ratio in the range of about 5:1 to about 20:1 also discloses molar ratios from 5:1 to 20:1 (e.g., from 10:1 to 15:1), and also includes any combination of ranges from 5:1 to 20:1 (e.g., the ratio can be in the range of 5:1 to 10:1, or 15:1 to 20:1). Similarly, all other ranges disclosed herein should be construed analogously to these examples.

[0019] The term "about" means that amounts, sizes, formulations, parameters, and other quantities and characteristics are not, and need not be, exact, but may be approximate (including larger or smaller values, as desired) to reflect tolerances, conversion factors, rounding, measurement error, and the like, as well as other factors known to those of ordinary skill in the art. In general, amounts, sizes, formulations, parameters, or other quantities or characteristics are "about" or "approximately," whether or not expressly stated. The term "about" also encompasses amounts that vary due to different equilibrium conditions for compositions resulting from a particular initial mixture. Whether or not modified by the term "about," the claims include the equivalent of that quantity. The term "about" can mean within 10% of the reported value, and often within 5% of the reported value.

[0020] All disclosed product yields are based on the limiting reactant in each reaction unless expressly stated otherwise. For example, the limiting reactant in the processes disclosed herein can be an alcohol compound (or an olefin compound), and therefore the conversion and yield are based on the initial amount of the alcohol compound (or an olefin compound).

[0021] Although any methods, devices, and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the exemplary methods, devices, and materials are described herein.

[0022] All publications and patents mentioned herein are incorporated by reference for the purpose of describing and disclosing, for example, the constructs and methodology described in the publications, which may be used in connection with the presently described invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] Detailed Description of the Invention Disclosed herein is a process for producing mercaptan compounds using a sulfur-containing nickel-molybdenum catalyst, which improves alcohol or olefin conversion, increases mercaptan yield and selectivity, and reduces sulfide by-products at reaction temperatures comparable to or lower than those of cobalt-molybdenum catalysts.

[0024] Synthesis of mercaptan compounds Mercaptan compounds can be produced by two general synthetic schemes. Consistent with certain embodiments of the present invention, a first method for producing mercaptan compounds can include (i) contacting a nickel-molybdenum catalyst with HS at a sulfiding temperature of about 235° C. or less to form a supported sulfur-containing catalyst, and (ii) contacting an alcohol compound, HS, and the supported sulfur-containing catalyst to form a reaction mixture containing the mercaptan compound. In the first method, the mercaptan compound can be represented by the formula (A):R 1The alcohol compound may have —SH, and the alcohol compound may have the formula (B): R 1 R may have -OH 1 is C1~C 18 The group may be a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group. Consistent with other aspects of the present invention, a second method for producing a mercaptan compound may include (i) contacting a nickel-molybdenum catalyst with H2S at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst; and (ii) contacting an olefin compound, H2S, and the supported sulfur-containing catalyst to form a reaction mixture containing the mercaptan compound. In the second method, the mercaptan compound may be represented by the formula (C):R 2 The olefin compound may have the formula C=C or the formula (D):R 1 -C=C, R 1 is C1~C 18 can be a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group, R 2 is C3~C 20 It can be a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group. As one skilled in the art will recognize, the R 1 and R 2 The choice of R in formula (D) is relevant. 1 is a C4 alkyl group, R in formula (C) 2 is a C6 alkyl group.

[0025] Generally, features of the first and second methods for producing mercaptan compounds (e.g., conditions under which the supported sulfur-containing catalyst is formed, particular alcohol and olefin reactants, and conditions under which the mercaptan compounds are formed, among others) are described independently herein, and these features can be combined in any combination to further describe the first and second processes of the present disclosure for producing mercaptan compounds. Furthermore, additional method steps can be performed before, between, and / or after these method steps, and, unless otherwise stated, can be utilized in any combination, without limitation, to further describe the first and second methods.

[0026] Formulas (A), (B), (C), and (D) are not designed to depict the stereochemistry or isomeric configuration of the different moieties (e.g., the formulas are not intended to depict cis or trans isomers), but such compounds are contemplated and encompassed by these formulas. 1 is C1~C 18 can be a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group, R 2 is C3~C 20 It can be a substituted or unsubstituted cycloalkyl group or a straight or branched alkyl group. In one embodiment, for example, R 1 is C1~C 14 In another embodiment, R 1 is C1~C 12 It can be a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group, and in yet another embodiment, R 1 can be a C1-C8 substituted or unsubstituted cycloalkyl group or a straight or branched alkyl group.

[0027] Consistent with aspects of the present invention, R 1 and R 2 can be a cycloalkyl group; alternatively, R 1 and R2 can be a linear alkyl group, or alternatively, R 1 and R 2 R can be a branched alkyl group. 1 and R 2 R is a cyclic, linear, or branched alkyl group. 1 and R 2 can be unsubstituted or substituted with any suitable substituent, any suitable number of substituents, and in any suitable position(s) consistent with the rules of chemical valence.

[0028] R 1 In a specific embodiment of the present invention, C1 to C 18 It can be a straight chain or branched alkyl group. Thus, R 1 is C1~C 14 Straight or branched alkyl groups, C1-C 12 It can be a straight or branched alkyl group, a C1-C8 straight or branched alkyl group, or a C1-C6 straight or branched alkyl group. 1 can be a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, or octadecyl group, or alternatively a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, or dodecyl group.

[0029] In other embodiments, in these formulas, R 1The alkyl group may be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, tert-amyl, n-hexyl, n-heptyl, n-octyl, or n-dodecyl; alternatively, methyl, ethyl, or isopropyl; alternatively, methyl or ethyl; alternatively, methyl; alternatively, ethyl Alternatively, it can be an n-propyl group; alternatively, an isopropyl group; alternatively, an n-butyl group; alternatively, an isobutyl group; alternatively, a sec-butyl group; alternatively, a tert-butyl group; alternatively, an n-pentyl group; alternatively, an isopentyl group; alternatively, a sec-pentyl group; alternatively, a neopentyl group; alternatively, a tert-amyl group; alternatively, an n-hexyl group; alternatively, an n-heptyl group; alternatively, an n-octyl group; or alternatively, an n-dodecyl group.

[0030] R 1 can be a cycloalkyl group in another aspect of the invention. 1 is C3~C 18 Cycloalkyl groups, C4-C 12 Cycloalkyl groups, C4-C 10 cycloalkyl group, or C5-C8 cycloalkyl group. Thus, in some embodiments, R 1 can be a cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, or cyclooctyl group; alternatively, a cyclobutyl group; alternatively, a cyclopentyl group; alternatively, a cyclohexyl group; alternatively, a cycloheptyl group; or alternatively, a cyclooctyl group.

[0031] In accordance with another aspect of the present invention, any alkyl group (cycloalkyl, straight chain alkyl, or branched alkyl) disclosed herein may be substituted with one or more substituents. Each non-hydrogen substituent(s) on the substituted alkyl group may independently be selected from the group consisting of C1 to C6. 18The hydrocarbyl substituent may be a benzyl group, a phenyl group, a tolyl group, or a xylyl group, etc., and therefore R in these formulas may be a C1-C8 hydrocarbyl group, or alternatively a C1-C6 hydrocarbyl group. 1 and R 2 can be, for example, a phenyl-substituted alkyl group. Additionally, the hydrocarbyl substituent can be a C1-C6 straight or branched alkyl group, and thus R in these formulas 1 and R 2 can be, for example, an alkyl-substituted cycloalkyl group (eg, a methylcyclohexyl group).

[0032] Illustrative, non-limiting examples of alcohol compounds that can be used in the first method to produce mercaptan compounds include methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, cyclopentanol, cyclohexanol, etc., and combinations thereof. Similarly, illustrative, non-limiting examples of olefin compounds that can be used in the second method to produce mercaptan compounds include ethylene, propylene, butene, pentene, hexene, heptene, octene, decene, dodecene, tetradecene, hexadecene, octadecene, cyclopentene, cyclohexene, etc., and combinations thereof.

[0033] Thus, illustrative, non-limiting examples of mercaptan compounds that can be prepared using the methods disclosed herein include methyl mercaptan, ethyl mercaptan, isopropyl mercaptan, sec-butyl mercaptan, and the like, and combinations thereof.

[0034] Step (i) in the first and second methods for producing mercaptan compounds can include contacting a nickel-molybdenum catalyst with HS at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst. Without wishing to be bound by theory, it is believed that the nickel-molybdenum catalyst first requires a sulfiding step to form a supported sulfur-containing catalyst, which in turn is effective in reacting an alcohol or olefin compound with HS in the presence of the supported sulfur-containing catalyst to form a reaction mixture containing mercaptan compounds. It has been found herein that an efficient method for sulfiding a base catalyst can include contacting a nickel-molybdenum catalyst with HS at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst, and that this sulfiding step can result in the surprisingly high alcohol / olefin conversion and mercaptan yield disclosed herein.

[0035] In step (i), the nickel-molybdenum catalyst can be contacted with HS at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst. This sulfiding step can be carried out at any suitable temperature of about 235°C or less for any suitable time period. Exemplary, non-limiting ranges for the sulfiding temperature in step (i) can be about 60°C to about 235°C, about 40°C to about 100°C, about 80°C to about 225°C, about 80°C to about 180°C, about 110°C to about 235°C, about 110°C to about 200°C, or about 110°C to about 160°C. These temperature ranges are also meant to encompass situations in which step (i) is carried out at a series of different temperatures rather than a single fixed temperature (at least one temperature within the recited range) falling within each temperature range.

[0036] In one embodiment, due to the exothermic nature of the sulfiding, step (i) can include contacting the nickel-molybdenum catalyst with inlet HS at a very low inlet sulfiding temperature (which can range from about 10° C. to about 90° C., from about 20° C. to about 80° C., from about 20° C. to about 60° C., or from about 35° C. to about 70° C., etc.).

[0037] Similarly, the time period for the sulfurization step (i) is not particularly limited and can be performed for any suitable time period. In some embodiments, the time period can be at least about 1 minute, at least about 5 minutes, at least about 10 minutes, at least about 30 minutes, at least about 1 hour, at least about 2 hours, at least about 5 hours, or at least about 10 hours. In other embodiments, the time period can be from about 30 seconds to about 48 hours, from about 1 minute to about 24 hours, from about 5 minutes to about 8 hours, from about 30 minutes to about 8 hours, or from about 1 hour to about 6 hours.

[0038] Step (i) and the sulfiding of the catalyst can be carried out at a sulfiding pressure ranging from about 50 to about 250 psig (344 to 1720 kPag), but is not limited thereto. Other exemplary, non-limiting ranges of sulfiding pressure include about 50 to about 200 psig (344 to 1379 kPag), about 100 to about 250 psig (689 to 1720 kPag), about 100 to about 200 psig (689 to 1379 kPag), or about 100 to about 150 psig (689 to 1034 kPag).

[0039] Generally, before sulfiding, the nickel-molybdenum catalyst is substantially free of sulfur, but after sulfiding in step (i), the supported sulfur-containing catalyst often contains about 3 to about 18 wt.% sulfur, e.g., about 4 to about 17 wt.%, about 5 to about 15 wt.%, or about 7 to about 13 wt.% sulfur. The amount of sulfur is based on the total weight of the supported sulfur-containing catalyst. Without wishing to be bound by theory, it is believed that the sulfiding step is necessary to obtain the surprisingly high alcohol / olefin conversions and mercaptan yields disclosed herein.

[0040] Optionally, the nickel-molybdenum catalyst can be dried or purged prior to step (i). Accordingly, the first and second methods for producing mercaptan compounds can further include, prior to step (i), contacting the nickel-molybdenum catalyst with an inert gas at any suitable purge temperature, which can often be about 235°C or less. For example, the purge temperature can be within the same temperature range as the sulfurization temperature disclosed herein, e.g., from about 60°C to about 200°C, from about 80°C to about 180°C, or from about 110°C to about 160°C. In certain embodiments, the purge temperature can be the same as the initial sulfurization temperature, and the nickel-molybdenum catalyst can be purged and then immediately sulfurized simply by changing the gas flow contacting the catalyst. Any suitable inert gas, such as helium, neon, argon, nitrogen, or any combination thereof, can be used in the purge step. Often, nitrogen is used as the inert gas.

[0041]

[0023] Referring now to step (ii), the suitable order of contacting (or reacting) step (ii) in the first and second methods for producing mercaptan compounds is not particularly limited. For example, the step of contacting (or reacting) an alcohol compound (or olefin compound), HS, and a supported sulfur-containing catalyst can include contacting these components in any order that results in an acceptable yield of the desired mercaptan compound. Typically, the alcohol compound (or olefin compound) and HS are first combined, and then the resulting reaction mixture is contacted with the supported sulfur-containing catalyst.

[0042] The first and second methods for producing mercaptan compounds can be carried out at any suitable temperature for any suitable time period. Representative, non-limiting ranges for the temperature of step (ii) (or the temperature for forming the mercaptan compounds) include about 100°C to about 300°C, about 125°C to about 275°C, about 175°C to about 275°C, about 175°C to about 250°C, about 200°C to about 300°C, about 200°C to about 275°C, or about 200°C to about 250°C. These temperature ranges are also intended to encompass situations in which step (ii) (or the formation of the mercaptan compounds) is carried out at a series of different temperatures rather than at a single fixed temperature (at least one temperature within the recited range) within each temperature range.

[0043] Similarly, the time period for contacting (or reacting) the alcohol compound (or olefin compound), HS, and the supported sulfur-containing catalyst is not particularly limited and can be any suitable time period. In some embodiments, the time period can be at least about 1 minute, at least about 5 minutes, at least about 10 minutes, at least about 30 minutes, at least about 1 hour, at least about 2 hours, at least about 5 hours, or at least about 10 hours. In other embodiments, the time period can be from about 30 seconds to about 48 hours, from about 1 minute to about 24 hours, from about 5 minutes to about 8 hours, from about 30 minutes to about 8 hours, or from about 1 hour to about 6 hours.

[0044] In many cases, the first and second methods for forming mercaptan compounds can be flow and / or continuous processes. In such situations, the contact time (or reaction time) of the alcohol compound (or olefin compound) and the catalyst can be expressed in terms of weight hourly space velocity (WHSV), which is the ratio of the weight of the alcohol compound (or olefin compound) contacting a given weight of catalyst per unit time (unit: g / g / hr).

[0045] Without limitation, the WHSV used in the process to produce the mercaptan compound can have a minimum value of 0.01, 0.02, 0.05, 0.1, 0.25, or 0.5, or alternatively a maximum value of 5, 4, 3, 2.5, 2, or 1. In general, the WHSV can range from any minimum WHSV disclosed herein to any maximum WHSV disclosed herein. In non-limiting embodiments, the WHSV can be in the range of about 0.01 to about 5, alternatively about 0.01 to about 3, alternatively about 0.01 to about 1, alternatively about 0.02 to about 4, alternatively about 0.02 to about 3, alternatively about 0.05 to about 2, alternatively about 0.05 to about 1.5, alternatively about 0.1 to 4, alternatively about 0.2 to about 3, alternatively about 0.2 to about 1.2, alternatively about 0.2 to about 1, alternatively about 0.5 to about 4, alternatively about 0.5 to about 2, or alternatively about 0.5 to about 1. Other WHSV ranges will be readily apparent from the rest of the disclosure. Any suitable reactor or vessel can be used to form the mercaptan compound, non-limiting examples of which include flow reactors, continuous reactors, packed tubes, and stirred tank reactors, including two or more reactors in series or parallel, and any combination of reactor types and configurations.

[0046] In some embodiments of the present invention, the first and second processes for producing mercaptan compounds can include contacting an alcohol compound (or an olefin compound) and H2S with a fixed bed of a supported sulfur-containing catalyst.

[0047] Without limitation, step (ii) and / or the formation of the mercaptan compound can be carried out at a reaction pressure ranging from about 50 to about 1,000 psig (344 to 6,890 kPag). Other exemplary, non-limiting ranges of reaction pressure include about 50 to about 500 psig (344 to 3,447 kPag), about 100 to about 800 psig (689 to 5,515 kPag), about 150 to about 450 psig (1,034 to 3,103 kPag), about 200 to about 450 psig (1,379 to 3,103 kPag), about 200 to about 350 psig (1,379 to 2,413 kPag), or about 300 to about 450 psig (2,068 to 3,103 kPag).

[0048] The molar ratio of HS:alcohol compound (or HS:olefin compound) is not particularly limited, as long as HS is used in excess. Typical ranges of the molar ratio of HS:alcohol compound (or HS:olefin compound) include, but are not limited to, about 3:1 to about 50:1, about 3:1 to about 18:1, about 3:1 to about 10:1, about 4:1 to about 30:1, about 4:1 to about 20:1, about 5:1 to about 20:1, about 5:1 to about 15:1, about 10:1 to about 30:1, or about 10:1 to about 15:1.

[0049] The methods described herein provide unexpectedly high molar conversions of alcohol or olefin compounds and / or molar yields to mercaptan compounds. In one embodiment, the minimum conversion (or yield) can be at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, or at least about 95%. In addition, the maximum conversion (or yield) can be about 97%, about 98%, about 99%, or about 99.5%, and can reach or approach 100% conversion of the alcohol or olefin compounds (or yield of mercaptans). Generally, the conversion (or yield) can be within a range from any minimum conversion (or yield) disclosed herein to any maximum conversion (or yield) disclosed herein. Non-limiting ranges of conversion (or yield) include about 50% to about 99.5%, about 70% to about 95%, about 80% to about 99%, about 90% to about 98%, or about 95% to 100%. In terms of moles, the percentage is the amount of alcohol compound (or olefin compound) reactant converted based on the initial amount of alcohol compound (or olefin compound). Yield values ​​are also molar percentages, based on moles of mercaptan compound produced per mole of alcohol compound (or olefin compound). In some embodiments, these conversion (or yield) rates can be achieved by a batch process; in other embodiments, these conversion (or yield) rates can be achieved by a flow process or a continuous process, for example, by a single pass or multiple passes through a reactor (e.g., a fixed-bed reactor).

[0050] Also unexpectedly, the continuous flow process for producing mercaptan compounds according to the present invention has an unexpectedly high single-pass molar conversion rate of olefinic or alcoholic compounds (or single-pass molar yield to the desired mercaptan compounds). In one embodiment, the minimum single-pass conversion rate (or yield) can be at least about 40%, at least about 50%, at least about 60%, at least about 70%, or at least about 80%. In addition, the maximum single-pass conversion rate (or yield) can be about 90%, about 95%, about 98%, or about 99%, and, depending on the reaction conditions, can reach or approach 100% conversion rate of the alcoholic or olefinic compounds (or yield of the mercaptan compounds). In general, the single-pass conversion rate (or yield) can be within a range from any minimum single-pass conversion rate (or yield) disclosed herein to any maximum single-pass conversion rate (or yield) disclosed herein. Non-limiting ranges for single-pass conversion (or yield) include about 40% to about 90%, about 50% to about 95%, about 60% to about 98%, or about 70% to 100%.

[0051] The first and second processes for producing mercaptan compounds disclosed herein typically result in a crude reaction mixture that includes mercaptan compounds, residual reactants, and relatively small amounts of by-products (e.g., non-mercaptan reaction products, such as sulfide heavies). Beneficially and unexpectedly, the amount of non-mercaptan reaction products (e.g., sulfides) in the reaction mixture is very low. For example, in one embodiment, the reaction mixture can include about 15 mol% or less of non-mercaptan reaction products, while in another embodiment, the reaction mixture can include about 10 mol% or less of non-mercaptan reaction products, and in yet another embodiment, the reaction mixture can include about 8 mol% or less (or 5 mol%, or 3 mol%) of non-mercaptan reaction products.

[0052] Beneficially, the selectivity of mercaptan compounds in the first and second processes, based on the total amount of mercaptan compounds in the reaction mixture, can be surprisingly high. For example, the selectivity of mercaptan compounds (based on the total amount of mercaptan compounds) can be at least about 75 mol%, alternatively at least about 80 mol%, alternatively at least about 85 mol%, alternatively at least about 90 mol%, or alternatively at least about 95 mol%.

[0053] In many cases, it may be desirable to separate the mercaptan compounds from the reaction mixture for sale or use in further industrial processes. Accordingly, in certain embodiments, the first and second methods for producing mercaptan compounds may further comprise a step of separating the mercaptan compounds to form a product stream comprising the mercaptan compounds. Isolation of the mercaptan compounds may employ any suitable technique for separating the mercaptan compounds from other components of the reaction mixture to form a product stream comprising the mercaptan compounds. Such techniques may include, but are not limited to, extraction, filtration, evaporation, or distillation, and combinations of two or more of these techniques. In certain embodiments of the present invention, the separation step utilizes distillation (one or more distillation columns may be used) at any suitable pressure. Advantageously, if the level of non-mercaptans in the reaction mixture is low, separation of, for example, the mercaptan compounds via distillation is a relatively straightforward process.

[0054] In addition, other components of the reaction mixture (e.g., unreacted alcohol or olefin compounds) can be recovered and recycled to the reactor after step (ii). In such cases, the alcohol or olefin compounds can be recycled until they are consumed, such that all or substantially all (greater than 99 mol%) of the reactants are converted to mercaptan compounds or by-products.

[0055] catalyst The nickel-molybdenum catalyst and the supported sulfur-containing catalyst can include any suitable solid support, including any suitable solid oxide or similar material. Illustrative solid supports include silica, alumina (e.g., γ-alumina), magnesia, boria, titania, zirconia, zeolites, and the like, as well as mixed oxides thereof (e.g., silica-alumina). A combination of support materials can be used in the catalyst.

[0056] When used, Y-zeolites (zeolite Y) and X-zeolites (zeolite X) can have average pore sizes ranging from about 7 Å to about 12 Å. The Si:Al ratio of X-zeolites is lower than that of Y-zeolites. Zeolites can often be bound with a support matrix (or binder), non-limiting examples of which include silica, alumina, magnesia, boria, titania, zirconia, various clays, and the like (including mixed oxides thereof), and mixtures thereof.

[0057] The amount of nickel present in the nickel-molybdenum catalyst and the supported sulfur-containing catalyst is not particularly limited, but is often in the range of about 1 to about 5 wt.%. In one embodiment, the amount of nickel can be about 1 to about 3 wt.%, in another embodiment, the amount of nickel can be about 2 to about 5 wt.%, in yet another embodiment, the amount of nickel can be about 2 to about 4 wt.%, and in yet another embodiment, the amount of nickel can be about 2.5 to about 4 wt.%. These weight percentages are based on the amount of nickel relative to the total weight of the nickel-molybdenum catalyst or the supported sulfur-containing catalyst.

[0058] Similarly, the amount of molybdenum on the catalyst is not particularly limited and typically ranges from about 4 to about 18 wt.%. In some embodiments, the nickel-molybdenum catalyst and the supported sulfur-containing catalyst can contain about 4 to about 16 wt.%, alternatively about 10 to about 15 wt.%, alternatively about 11 to about 17 wt.%, or alternatively about 13 to about 16 wt.% molybdenum, based on the total weight of each catalyst. Without wishing to be bound by theory, it is believed that higher molybdenum loadings improve conversion and / or yield.

[0059] Generally, the nickel-molybdenum catalyst and the supported sulfur-containing catalyst prior to use contain little or no carbon, e.g., about 3 wt.% or less of carbon. More often, each catalyst contains about 2.5 wt.% or less of carbon, about 2 wt.% or less of carbon, about 1 wt.% or less of carbon, or about 0.5 wt.% or less of carbon. As above, these weight percentages are based on the total weight of the respective nickel-molybdenum catalyst or supported sulfur-containing catalyst.

[0060] While nickel-molybdenum catalysts are substantially free of sulfur before sulfiding, supported sulfur-containing catalysts (after sulfiding) often contain at least about 3 wt.% sulfur, or up to about 18 wt.% sulfur. Exemplary, non-limiting ranges for the amount of sulfur in the supported sulfur-containing catalyst include about 4 to about 17 wt.%, about 5 to about 15 wt.%, about 7 to about 13 wt.%, and the like. These weight percentages are based on the total weight of the supported sulfur-containing catalyst. While not wishing to be bound by theory, it is believed that an appropriate level of sulfur is necessary to obtain the surprisingly high alcohol / olefin conversions and mercaptan yields disclosed herein.

[0061] The nickel-molybdenum catalyst and the supported sulfur-containing catalyst may be any suitable BET surface area (about 75 to about 400 m 2 / g, about 100~350m 2 / g, about 100~300m 2 / g, approx. 125~275m2 / g, about 150~375m 2 / g, or about 150 to about 250 m 2 / g).

[0062] The nickel-molybdenum catalyst and the supported sulfur-containing catalyst can have any suitable shape or form, which may depend on the type of process (e.g., fixed bed vs. fluidized bed) used to convert the alcohol or olefin reactant to the mercaptan compound. Exemplary, non-limiting shapes and forms include powders, round or spherical (e.g., spheres), ellipsoids, pellets, beads, cylinders, granules (e.g., regular and / or irregular), trilobal, tetralobal, rings, wagon wheels, monoliths, and the like, and any combination thereof. Accordingly, various methods can be used to prepare the supported catalyst particles, including, for example, extrusion, spray drying, pelletizing, marumerizing, spheronizing, agglomeration, oil droplets, and the like, and combinations thereof.

[0063] In some embodiments, the nickel-molybdenum catalyst and the supported sulfur-containing catalyst can be in the form of pellets or beads (or the like) having an average particle size (or average diameter) ranging from about 0.5 to about 15 mm, from about 1 to about 7 mm, or from about 2.5 to about 5 mm. As noted above, the size of the nickel-molybdenum catalyst and the supported sulfur-containing catalyst particles can be varied to suit a particular process for converting alcohol or olefin reactants to mercaptan compounds.

[0064] example The present invention is further illustrated by the following examples, which should not be construed as imposing limitations on the scope of the present invention in any way. Various other embodiments, modifications, and equivalents thereof may be suggested to those skilled in the art after reading the description herein, without departing from the spirit of the present invention or the scope of the appended claims.

[0065] These examples demonstrate that the sulfur-containing nickel molybdenum catalysts utilized herein provide both better activity and selectivity in the production of mercaptans from HS and either olefins or alcohols than cobalt molybdenum catalysts. In addition, increases in conversion and mercaptan product yield (e.g., 5-10% increases) were obtained at significantly less severe operating conditions (i.e., lower reaction temperatures, higher hydrocarbon space velocities, and lower HS:olefin or HS:alcohol feed ratios).

[0066] Examples 1-2 In Examples 1-2, methyl mercaptan (MeSH) was synthesized from methanol (MeOH) and H2S. For every mole of methanol that reacts, one mole of water is produced. Methanol can further react (e.g., with MeSH) to form dimethyl sulfide (DMS) and water. At higher temperatures, the production of DMS is generally favored over MeSH, where MeSH is the desired product. Additionally, methanol (and MeSH) can decompose to form CO2 (and CS2) and hydrogen, and higher temperatures increase the rate of these unwanted decomposition reactions.

[0067] Examples 1-2 used a 1-inch stainless steel reactor with downflow, and the catalyst was diluted with 14-20 mesh Alundum® to help establish isothermal reactor operation. A 1 / 4-inch centerline thermowell equipped with three thermocouples was used for temperature measurements, and the reaction temperature (Temp) was taken as the arithmetic mean of the three temperatures (note that the temperatures of the three thermocouples were typically within 2°C of each other).

[0068] The reaction mixture was analyzed using an online HP-6580 gas chromatograph equipped with a thermal conductivity detector. The temperature profile was 35 °C for 5 min, then increased to 70 °C at 5 °C / min, followed by an increase to 260 °C at 15 °C / min and a 10 min hold. The column was a CP-Sil 5CB, 30 m x 320 μm x 4 μm, with a 0.5 mL / min He flow for sulfur. The detector was operated at 200 °C, and the following response factors were used: CO 0.92; H 2 S 0.88; H 2 O 0.55; dimethyl ether (DME) 0.67; MeOH 0.58; MeSH 0.81; CS 0.82; DMS 0.80; and dimethyl disulfide (DMDS) 0.80.

[0069] For Example 1, Table 1 summarizes the results for an experiment to synthesize methyl mercaptan from methanol and HS using a cobalt molybdate catalyst (CoMo, 3 wt. % Co and 11 wt. % Mo, fresh catalyst basis) at an HS:methanol molar feed ratio of 7.6:1, Table 2 summarizes the results for an HS:methanol molar feed ratio of 10.8:1, and Table 3 summarizes the results for an HS:methanol molar feed ratio of 15.5:1. The MeSH yield is defined as the product of methanol conversion and selectivity to methyl mercaptan.

[0070] The results from Example 1 indicate that a minimum temperature of at least 240°C is required for 99 mol% methanol conversion using a cobalt molybdate catalyst, while maximum MeSH yield (product of conversion and selectivity) occurs between 220 and 230°C. 99 mol% methanol conversion was not obtained at any temperature below 240°C at a feed ratio of 7.6:1, and 100 percent methanol conversion was not observed at any temperature below 240°C. A higher feed molar ratio of 15.5:1 was more selective to MeSH than a feed ratio of 10.8:1, and therefore produced a higher MeSH yield than a ratio of 7.6:1.

[0071] The highest yield of methyl mercaptan obtained was 89-90 mol% (15.5:1 feed ratio, 220 °C), but under these conditions, the methanol conversion was less than 99 mol%. The highest methyl mercaptan yield, with at least 99% methanol conversion, was 88.8 mol% (15.5:1 feed ratio, 240 °C).

[0072] For Example 2, Table 4 summarizes the results for an H2S:methanol feed ratio of 9.9:1, Table 5 summarizes the results for an H2S:methanol feed ratio of 14.8:1, and Table 6 summarizes the results for an H2S:methanol feed ratio of 17.1:1 in experiments to synthesize methyl mercaptan from methanol and H2S using a nickel molybdate catalyst (NiMo, 3 wt. % Ni and 10-11 wt. % Mo, fresh catalyst basis). The MeSH yield is defined as the product of the methanol conversion and the selectivity to methyl mercaptan.

[0073] The results of Example 2 show that virtually complete (>99 mol%) methanol conversion was achieved at 220°C (or higher) with the NiMo catalyst of Example 2, whereas 240°C was required with the CoMo catalyst of Example 1. Furthermore, 100 mol% methanol conversion was not observed at any temperature with the CoMo catalyst of Example 1, whereas 100 mol% methanol conversion in Example 2 was achieved at 230°C or higher (feed ratios greater than 14:1). As with Example 1, higher molar HS / methanol feed ratios resulted in higher MeSH selectivity in Example 2. However, the NiMo catalyst of Example 2 produced a 91.8 mol% MeSH yield (at >99 mol% methanol conversion), a yield not achieved with the CoMo catalyst of Example 1 (88.8 mol% MeSH yield at >99 mol% methanol conversion).

[0074] Additionally, operating at or near 100% methanol conversion, as in Example 2 using a NiMo catalyst, is desirable because it eliminates the need for downstream separation or purification to remove or recycle unreacted methanol. Methanol can be difficult to remove from the product MeSH because it does not form a low-boiling azeotrope with water. Typically, for commercial MeSH products, methanol concentrations must often be below 400 ppmw.

[0075] Examples 3-4 In Examples 3 and 4, isopropyl mercaptan (IPM, 2-propanethiol) was synthesized from propylene and H2S. Examples 3 and 4 were conducted and analyzed in the same manner as Examples 1 and 2, except that a jacketed 6-inch ID 5% chromium steel reactor was used in the downflow direction, the temperatures of the inlet feed and effluent reaction mixture were measured with thermocouples, and the reaction temperature (temperature) was taken as the arithmetic mean of the inlet and outlet temperatures.

[0076] The reaction mixture was analyzed using an Agilent 6850A gas chromatograph equipped with an Agilent G2613A liquid autosampler. The GC was equipped with a thermal conductivity detector operating at 300 °C. The temperature profile was 50 °C for 1.5 min, then increased to 100 °C at 20 °C / min, followed by a 50 °C / min increase to 275 °C and a 1.5 min hold. The column was DB-1 (polysiloxane standard), 15 m x 320 μm x 1 μm, with a 0.8 mL / min H2 flow, operated in ascending flow mode.

[0077] For Example 3, Table 7 summarizes the results of experiments to synthesize IPM from propylene and HS using a cobalt molybdate catalyst (CoMo, 3 wt.% Co and 10-11 wt.% Mo, fresh catalyst basis) at HS:propylene molar feed ratios of 9:1 to 11:1, reaction pressures of 330 psig, and feed rates of 0.6 to 0.7 WHSV based on propylene. Table 7 shows the composition of the reaction mixture as a function of temperature, with isopropyl mercaptan (IPM), normal propyl mercaptan (NPM), and undesired heavies (sulfides such as di-normal propyl sulfide or isopropyl-normal propyl sulfide) being the primary products.

[0078] From Table 7, the highest yield of IPM in the reactor effluent was 78.4 mol% using the CoMo catalyst, while typical yields were several percentage points lower. The highest combined yield of IPM and NPM was 87.4 mol%. Reactor temperatures above approximately 400°F were required to achieve these results. Under these conditions, the average amount of sulfide was 10.6 mol%, and unreacted propylene ranged from 0.4 to 1.2 mol%.

[0079] For Example 4, Table 8 summarizes the results of an experiment to synthesize IPM from propylene and HS using a nickel molybdate catalyst (NiMo, 3.4 wt. % Ni and 14 wt. % Mo, fresh catalyst basis) at an HS:propylene molar feed ratio of 8.8:1, a reaction pressure of 330 psig, and a feed rate of 0.73 WHSV based on propylene. Table 8 shows the composition of the reaction mixture as a function of temperature, with isopropyl mercaptan (IPM), normal propyl mercaptan (NPM), and undesired heavies (sulfides such as di-normal propyl sulfide or isopropyl-normal propyl sulfide) being the primary products.

[0080] Also for Example 4, Table 9 summarizes the results of experiments to synthesize IPM from propylene and HS using a nickel molybdate catalyst (NiMo, 3.4 wt.% Ni and 14 wt.% Mo, fresh catalyst basis) at HS:propylene molar feed ratios of 6:1 to 8:1, reaction pressures of 330 psig, and feed rates of 0.8 to 0.9 WHSV based on propylene. Table 9 shows the composition of the reaction mixture as a function of temperature, with isopropyl mercaptan (IPM), normal propyl mercaptan (NPM), and undesired heavies (sulfides such as di-normal propyl sulfide or isopropyl-normal propyl sulfide) being the primary products.

[0081] From Tables 8-9, the highest yield of IPM in the reactor effluent was 88.2 mol% using the NiMo catalyst, while typical yields were above 85 mol%. The highest combined yield of IPM and NPM was 96.2 mol%. To achieve these results, a reactor temperature of only about 365-380°F was used. Under these conditions, the average amount of sulfide was less than 5 mol%, and the unreacted propylene ranged below 0.1 mol%.

[0082] Comparing Example 3 (CoMo) and Example 4 (NiMo), the highest IPM yield in Example 4 (88.2 mol%) was 9.8 mol% higher than the highest IPM yield in Example 3, and this was achieved at a 30°F lower temperature using the NiMo catalyst in Example 4. Furthermore, the amount of unreacted propylene in Example 4 was 0.1 mol% or less in the reactor mixture when using the nickel molybdate catalyst in Example 4 compared to the cobalt molybdate catalyst in Example 3, despite operating at up to 20% higher space velocity and 27°F lower temperature.

[0083] The amount of unwanted sulfide was consistently low (maximum 7.4%) with the NiMo catalyst, while the CoMo catalyst had a minimum of 8.8%. The lower reactor temperature required for increased IPM production allowed for approximately half of the sulfide formation when using the NiMo catalyst. This combination of high product yield and high propylene conversion while operating at a lower reaction temperature compared to the CoMo catalyst is a significant and unexpected advantage of the NiMo catalyst for isopropyl mercaptan synthesis.

[0084] Examples 5-6 In Examples 5-6, sec-butyl mercaptan (SBM, 2-butanethiol) was synthesized from 1-butene and H2S. Examples 5-6 were carried out and analyzed in the same manner as Examples 3-4. The reaction mixtures were analyzed using an Agilent 6850A gas chromatograph equipped with an Agilent G2613A liquid autosampler. The GC was equipped with flame ionization detection operated at 300 °C. The temperature profile was 35 °C held for 1.8 min, then ramped to 250 °C at 30 °C / min and held for 2 min. The column was DB-1 (polysiloxane standard), 30 m x 320 μm x 0.25 μm, with a 1.5 mL / min H2 flow, operated in pressure ramp mode.

[0085] For Examples 5-6, Table 10 summarizes the results of experiments to synthesize SBM from 1-butene and HS using a cobalt molybdate catalyst (CoMo, 3 wt.% Co and 10 wt.% Mo, fresh catalyst basis, Examples 5A and 5B) and a nickel molybdate catalyst (NiMo, 3.4 wt.% Ni and 14 wt.% Mo, fresh catalyst basis, Example 6). Table 10 shows the reaction mixture composition and reaction temperature, with the main products being sec-butyl mercaptan (SBM), n-butyl mercaptan (NBM), and undesired heavies (sulfides such as di-n-butyl sulfide, di-sec-butyl sulfide, and secondary n-butyl sulfide). WHSV values ​​were based on 1-butene.

[0086] When the CoMo catalyst was used in Examples 5A and 5B, the highest SBM yield in the reaction mixture was 73.7 wt.%, with an average SBM yield of 71.5 wt.% and a mercaptan yield of 81.5 wt.%. The reaction temperature was 404°F, resulting in 8-12 wt.% sulfides and over 6 wt.% unreacted 1-butene. When the NiMo catalyst was used in Example 6, the SBM yield in the reaction mixture was surprisingly 10 wt.% greater than the average yield in Example 5, achieved at a temperature 33°F lower. Sulfides were reduced by 2-5 wt.% and unreacted butenes by 1 wt.%, while a 15% higher space velocity and a 32% lower HS:butene feed ratio were used.

[0087] Example 7 Example 7 summarizes the pre-sulfiding or sulfiding of a base catalyst with HS. Sulfiding of catalysts for use in mercaptan synthesis cannot be performed using diesel hydrocarbons due to concerns about product purity in the synthesis and production of mercaptan products. Furthermore, most refineries do not have HS available at pressures above about 30 psig. The base NiMo catalyst used in Examples 3-6 was sulfided with HS at pressures above 100 psig. The use of high-pressure HS mitigated the temperature rise during the exothermic catalytic sulfidation reaction (e.g., MoO + 2HS → MoS + 2H0). Isothermal conditions are typically desired during sulfiding to maximize catalyst activity and effectiveness.

[0088] Prior to sulfiding, the base NiMo catalyst was purged with nitrogen at 120-150°C for approximately 10 hours and then presulfided for less than 24 hours using a gas stream of HS at a pressure above 100 psig (but less than 250 psig), resulting in approximately 10-11 wt.% sulfur on the sulfided catalyst. Table 11 presents time and temperature data from a typical presulfiding experiment. The maximum temperature during sulfiding was recorded at 283°F, while the maximum weight-average sulfiding temperature was 184°F. During this temperature spike, the amount of reactor preheat was reduced for two hours to help mitigate the extent of the temperature rise. After the temperature in the reactor began to rise, the HS feed rate was also reduced for several hours to help mitigate the temperature rise in the reactor.

[0089] Examples 8-9 In Examples 8-9, ethyl mercaptan (ethylenethiol) was synthesized from ethylene and HS. Examples 8-9 were conducted and analyzed in the same manner as Examples 5-6, except that a jacketed tubular reactor with 2-inch stainless steel piping was used for the downflow, the temperatures of the inlet feed and eluted reaction mixture were measured with thermocouples, and the reaction temperature (temperature) was taken as the arithmetic mean of the inlet and outlet temperatures. Analysis of the eluted reaction mixture was performed using an online gas chromatograph equipped with a flame ionization detector. The main components of the eluted reaction mixture were the desired product, ethyl mercaptan (ethanethiol), and undesired heavy sulfides, including diethyl sulfide and diethyl disulfide.

[0090] For Examples 8-9, Table 12 summarizes the results of experiments to synthesize ethyl mercaptan from ethylene and HS using a cobalt molybdate catalyst (CoMo, 3 wt.% Co and 11 wt.% Mo, fresh catalyst basis, Example 8) and a nickel molybdate catalyst (NiMo, 3.4 wt.% Ni and 14 wt.% Mo, fresh catalyst basis, Example 9). Sulfidation was carried out as described in Example 7. Table 12 shows the reaction mixture composition and reaction temperature, with ethyl mercaptan and undesired heavies (sulfides such as diethyl sulfide and diethyl disulfide) being the major products. WHSV values ​​are based on ethylene, and the HS:ethylene molar ratio was 5.1-5.2:1.

[0091] From Table 12, the maximum achievable ethyl mercaptan concentration in the reactor effluent was 5.6 wt.% higher using the NiMo catalyst (Example 9) compared to the CoMo catalyst (Example 8). While operating at the same reactor pressure, ethylene space velocity, and HS:ethylene ratio, the reaction temperature was 43°C lower using the NiMo catalyst compared to the CoMo catalyst, while simultaneously achieving the maximum ethyl mercaptan conversion (just over 99.9 wt.%) across the reactor outlet.

[0092] This lower reaction temperature represents a substantial operational advantage in that it reduces both the amount of reactor preheat required and the preheat feed temperature. Furthermore, as a result of the lower operating temperature, the production of unwanted sulfides and disulfides was also reduced by 44%. This reduction in the amount of sulfides and disulfides was not achieved at any reactor conditions using a CoMo catalyst while converting more than 90 wt.% ethylene on a single pass basis.

[0093] Advantageously, the NiMo catalyst used in Example 9 provided significant increases in both catalytic activity and yield. With regard to activity, the exceptional activity of the NiMo catalyst resulted in an ethylene conversion of over 99.9 wt.% at a temperature 43°C lower than that achieved with the CoMo catalyst (at its highest ethylene conversion (only 96.5 wt.%)) under otherwise identical reactor operating conditions. With regard to yield, Example 9 using the NiMo catalyst achieved an ethyl mercaptan yield of 97.1 wt.%, which was also unexpectedly higher than the yield achieved with the CoMo catalyst in Example 8. [Table 1] [Table 2] [Table 3] [Table 4] [Table 5] [Table 6] [Table 7-9] [Table 10] [Table 11] [Table 12]

[0094] The present invention has been described above with reference to numerous aspects and examples. Many variations will suggest themselves to those skilled in the art in light of the above detailed description. All such obvious variations are within the fully intended scope of the appended claims. Other aspects of the present invention include, but are not limited to, the following (although aspects are described as "comprising," they may alternatively be "consisting essentially of" or "consisting of"):

[0095] Aspect 1. A method for producing a mercaptan compound, said method comprising: (i) contacting a nickel-molybdenum catalyst with H2S at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst; (ii) contacting an alcohol compound, H2S, and the supported sulfur-containing catalyst to form a reaction mixture comprising the mercaptan compound.

[0096] Aspect 2. A method for producing a mercaptan compound, said method comprising: (i) contacting a nickel-molybdenum catalyst with H2S at a sulfiding temperature of about 235°C or less to form a supported sulfur-containing catalyst; (ii) contacting an olefin compound, H2S, and the supported sulfur-containing catalyst to form a reaction mixture comprising the mercaptan compound.

[0097] Aspect 3. The mercaptan compound has the formula (A): R 1 -SH, The alcohol compound is represented by the formula (B): R 1 -OH, R 1 However, C1~C 18 The method defined in embodiment 1, wherein the alkyl group is a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group.

[0098] Aspect 4. The mercaptan compound has the formula (C): R 2 -SH, The olefin compound has the formula C═C or the formula (D): R 1 -C=C, R 1 However, C1~C 18 a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group, R 2 But C3~C 20 The method defined in embodiment 2, wherein the alkyl group is a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group.

[0099] Aspect 5. The method defined in any one of the preceding aspects, further comprising, prior to step (i), contacting the nickel-molybdenum catalyst with an inert gas at a purge temperature of about 235° C. or less.

[0100] Embodiment 6. The method defined in embodiment 5, wherein the inert gas comprises any suitable inert gas or any inert gas disclosed herein, such as helium, neon, argon, nitrogen, or the like, or any combination thereof.

[0101] Embodiment 7. The method defined in embodiment 5 or 6, wherein the purge temperature is any suitable purge temperature or any range of temperatures disclosed herein, e.g., from about 60°C to about 200°C, from about 110°C to about 160°C, etc.

[0102] Embodiment 8. The method defined in any one of the preceding embodiments, wherein the sulfurization temperature is any suitable sulfurization temperature or any range of temperatures disclosed herein, e.g., from about 60°C to about 200°C, from about 40°C to about 100°C, from about 110°C to about 160°C, etc.

[0103] Aspect 9. The method defined in any one of the preceding aspects, wherein step (i) comprises contacting the nickel-molybdenum catalyst with inlet HS at an inlet sulfiding temperature of from about 10°C to about 90°C, such as from about 35°C to about 70°C.

[0104] Aspect 10. The method defined in any one of the preceding aspects, wherein step (i) is carried out at any suitable sulfiding pressure or any range of pressures disclosed herein, e.g., from about 50 to about 250 psig, from about 100 to about 150 psig, etc.

[0105] Embodiment 11. The method defined in any one of the preceding embodiments, wherein the nickel-molybdenum catalyst and the supported sulfur-containing catalyst comprise any suitable amount of nickel or any range of amounts disclosed herein, e.g., about 1 to about 5 wt.%, about 1 to about 3 wt.%, about 2 to about 5 wt.%, about 2 to about 4 wt.%, about 2.5 to about 4 wt.%, etc., of nickel based on the total weight of the respective catalysts.

[0106] Aspect 12. The method defined in any one of the preceding aspects, wherein the nickel-molybdenum catalyst and the supported sulfur-containing catalyst comprise any suitable amount of molybdenum or any range of amounts disclosed herein, such as, for example, about 4 to about 18 wt.%, about 4 to about 16 wt.%, about 10 to about 15 wt.%, about 11 to about 17 wt.%, about 13 to about 16 wt.%, etc., of molybdenum based on the total weight of the respective catalysts.

[0107] Embodiment 13. The method defined in any one of the preceding embodiments, wherein the supported sulfur-containing catalyst comprises any suitable amount of sulfur or any range of amounts disclosed herein, such as, for example, about 3 to about 18 wt.%, about 4 to about 17 wt.%, about 5 to about 15 wt.%, about 7 to about 13 wt.%, etc., sulfur based on the total weight of the catalyst.

[0108] Embodiment 14. The method defined in any one of the preceding embodiments, wherein the nickel-molybdenum catalyst and the supported sulfur-containing catalyst comprise any suitable amount of carbon or any range of amounts disclosed herein, such as, for example, about 3 wt.% or less, about 2.5 wt.% or less, about 2 wt.% or less, about 1 wt.% or less, about 0.5 wt.% or less, based on the total weight of each of the catalysts.

[0109] Embodiment 15. The method defined in any one of the preceding embodiments, wherein the nickel-molybdenum catalyst and the supported sulfur-containing catalyst comprise any suitable solid support or any solid support disclosed herein, e.g., a solid support comprising silica, alumina (e.g., γ-alumina), magnesia, boria, titania, zirconia, zeolite, or the like, or mixed oxides thereof, or mixtures thereof.

[0110] Embodiment 16. The nickel-molybdenum catalyst and the supported sulfur-containing catalyst have any suitable BET surface area or any BET surface area disclosed herein, for example, from about 100 to about 300 m 2 / g, approx. 125~275m 2 / g, about 150~250m 2 The method defined in any one of the preceding aspects, characterized by, for example, / g.

[0111] Embodiment 17. The method defined in any one of the preceding embodiments, wherein the nickel-molybdenum catalyst and the supported sulfur-containing catalyst are in any suitable shape or form, or any shape or form disclosed herein, such as, for example, powder, round or spherical (e.g., sphere), oval, pellet, bead, cylinder, granule (e.g., regular and / or irregular), trilobal, tetralobal, ring, wagon wheel, monolith, etc., or any combination thereof.

[0112] Embodiment 18. The method defined in any one of the preceding embodiments, wherein the nickel-molybdenum catalyst and the supported sulfur-containing catalyst are characterized by any suitable average particle size (or average diameter) or any average particle size (or average diameter) disclosed herein, e.g., from about 0.5 to about 15 mm, from about 1 to about 7 mm, from about 2.5 to about 5 mm, etc.

[0113] Aspect 19.R 1 and R 2 19. The method defined in any one of aspects 3 to 18, wherein is a branched alkyl group.

[0114] Aspect 20.R 1 and R 2 19. The method defined in any one of aspects 3 to 18, wherein is a linear alkyl group.

[0115] Aspect 21.R 1 and R 2 The method defined in any one of aspects 3 to 20, wherein is a substituted alkyl group (e.g., a phenyl-substituted alkyl group).

[0116] Aspect 22.R 1 C1~C 12 The method defined in any one of aspects 3 to 21, wherein the alkyl group is an alkyl group.

[0117] Aspect 23.R 1is a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a cyclopentyl group, or a cyclohexyl group.

[0118] Aspect 24.R 1 19. The method defined in any one of aspects 3 to 18, wherein is a methyl group, an ethyl group, a propyl group, or a butyl group.

[0119] Aspect 25.R 1 is a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a neopentyl group, or a tert-amyl group.

[0120] Aspect 26. The method defined in any one of aspects 1 to 18, wherein the mercaptan compound is methyl mercaptan, ethyl mercaptan, isopropyl mercaptan, or sec-butyl mercaptan.

[0121] Embodiment 27. The method defined in any one of the preceding embodiments, wherein the method comprises combining the alcohol compound (or the olefin compound) with H2S prior to contacting with the supported sulfur-containing catalyst.

[0122] Embodiment 28. The method defined in any one of the preceding embodiments, wherein step (ii) is carried out at a temperature in any suitable range or any range disclosed herein (e.g., from about 100°C to about 300°C, from about 175°C to about 275°C, from about 200°C to about 250°C, etc.).

[0123] Embodiment 29. The method defined in any one of the preceding embodiments, wherein step (ii) is carried out at a pressure in any suitable range or any range disclosed herein (e.g., from about 50 to about 1000 psig, from about 100 to about 800 psig, from about 150 to about 450 psig, etc.).

[0124] Embodiment 30. The method defined in any one of the preceding embodiments, wherein the molar ratio of H2S:alcohol compound (or H2S:olefin compound) is any suitable range or any range disclosed herein (e.g., from about 3:1 to about 10:1, from about 4:1 to about 30:1, from about 5:1 to about 20:1, from about 10:1 to about 15:1, etc.).

[0125] Aspect 31. The method defined in any one of the preceding aspects, wherein the method comprises contacting the alcohol compound (or the olefin compound) and H2S with a fixed bed of the supported sulfur-containing catalyst.

[0126] Embodiment 32. The method defined in any one of the preceding embodiments, wherein step (ii) is carried out at any suitable WHSV or at a WHSV within any range disclosed herein (e.g., from about 0.01 to about 3, from about 0.05 to about 1.5, from about 0.2 to about 1, etc.).

[0127] Embodiment 33. The method defined in any one of the preceding embodiments, wherein the conversion of the alcohol compound or the olefin compound (or the yield to the mercaptan compound) is any molar percent conversion (or molar yield) disclosed herein (e.g., at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, etc.).

[0128] Embodiment 34. The method defined in any one of the preceding embodiments, wherein the single-pass conversion of the alcohol compound or the olefin compound (or the single-pass yield to the mercaptan compound) is any single-pass molar percent conversion (or single-pass molar yield) disclosed herein (e.g., at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, etc.).

[0129] Embodiment 35. The method defined in any one of the preceding embodiments, wherein the reaction mixture comprises about 15 mol % or less of non-mercaptan reaction products (e.g., sulfides), about 10 mol % or less of non-mercaptan reaction products, about 5 mol % or less of non-mercaptan reaction products, etc.

[0130] Embodiment 36. The method defined in any one of the preceding embodiments, wherein the selectivity of the mercaptan compounds is any selectivity disclosed herein (e.g., at least about 75 mol%, at least about 80 mol%, at least about 85 mol%, at least about 90 mol%, at least about 95 mol%, etc., based on the total amount of the mercaptan compounds in the reaction mixture).

[0131] Aspect 37. The method defined in any one of the preceding aspects, further comprising isolating the mercaptan compound from the reaction mixture using any suitable technique or any technique disclosed herein (e.g., extraction, filtration, evaporation, distillation, the like, or any combination thereof) to form a product stream comprising the mercaptan compound.

[0132] Aspect 38. The method defined in any one of the preceding aspects, wherein after step (ii), the unreacted alcohol compound (or unreacted olefin compound) is recycled. The following is further disclosed regarding the present invention. [1] 1. A method for producing a mercaptan compound, the method comprising: (i) Sulfiding a nickel-molybdenum catalyst at a sulfiding temperature of about 235°C or less with H 2 S to form a supported sulfur-containing catalyst; (ii) an alcohol compound and H2 and contacting S with the supported sulfur-containing catalyst to form a reaction mixture comprising the mercaptan compound. [2] 1. A method for producing a mercaptan compound, the method comprising: (i) Sulfiding a nickel-molybdenum catalyst at a sulfiding temperature of about 235°C or less with H 2 S to form a supported sulfur-containing catalyst; (ii) an olefin compound and H 2 and contacting S with the supported sulfur-containing catalyst to form a reaction mixture comprising the mercaptan compound. [3] The mercaptan compound is represented by the formula (A): R 1 -SH, The alcohol compound is represented by the formula (B): R 1 -OH, R 1 But C 1 ~C 18 The method according to [1], wherein the alkyl group is a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group. [4] The mercaptan compound is represented by the formula (C): R 2 -SH, The olefin compound has the formula C═C or the formula (D): R 1 -C=C, R 1 But C 1 ~C 18 a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group, R 2 But C 3 ~C 20 The method according to [2], wherein the alkyl group is a substituted or unsubstituted cycloalkyl group or a linear or branched alkyl group. [5] R 1 and R 2 The method according to [3] or [4], wherein [6] R 1 C 1 ~C 12 The method according to any one of [3] to [5], wherein the group is an alkyl group. [7] R 1 is a methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, cyclopentyl group, or cyclohexyl group. [8] 10. The method of claim 1, wherein the alcohol compound comprises methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, cyclopentanol, cyclohexanol, or any combination thereof. [9] 3. The method of claim 2, wherein the olefin compound comprises ethylene, propylene, butene, pentene, hexene, heptene, octene, decene, dodecene, tetradecene, hexadecene, octadecene, cyclopentene, cyclohexene, or any combination thereof.

[10] The method according to [1] or [2], wherein the mercaptan compound is methyl mercaptan, ethyl mercaptan, isopropyl mercaptan, or sec-butyl mercaptan.

[11] Step (i) a sulfurization temperature of about 60°C to about 235°C, about 60°C to about 200°C, about 40°C to about 100°C, about 80°C to about 225°C, about 80°C to about 180°C, about 110°C to about 235°C, about 110°C to about 200°C, or about 110°C to about 160°C; and The method according to any one of [1 to 10], wherein the sulfurization pressure is about 50 to about 250 psig, about 50 to about 200 psig, about 100 to about 250 psig, about 100 to about 200 psig, or about 100 to about 150 psig.

[12] Step (i) is to introduce the nickel-molybdenum catalyst into an inlet H 2 The method according to any one of [1] to

[10] , comprising contacting the catalyst with S at an inlet sulfurization temperature of about 10°C to about 90°C, about 20°C to about 80°C, about 20°C to about 60°C, or about 35°C to about 70°C.

[13] Step (ii) a temperature within the range of about 100°C to about 300°C, about 125°C to about 275°C, about 175°C to about 275°C, about 175°C to about 250°C, about 200°C to about 300°C, about 200°C to about 275°C, or about 200°C to about 250°C; pressures in the range of about 50 to about 1000 psig, about 50 to about 500 psig, about 100 to about 800 psig, about 150 to about 450 psig, about 200 to about 450 psig, about 200 to about 350 psig, or about 300 to about 450 psig; and Any of the aforementioned methods, wherein the method is carried out at a WHSV in the range of about 0.01 to about 5, about 0.02 to about 3, about 0.05 to about 1.5, about 0.1 to about 4, about 0.2 to about 3, about 0.2 to about 1.2, about 0.2 to about 1, about 0.5 to about 2, or about 0.5 to about 1.

[14] Step (ii) is a step of reacting the alcohol compound or the olefin compound and H 2 Any of the preceding methods comprising contacting S with a fixed bed of said supported sulfur-containing catalyst.

[15] H 2 S: Alcohol compound or H 2 Any of the above-mentioned methods, wherein the molar ratio of S:olefin compound is within the range of about 3:1 to about 50:1, about 3:1 to about 18:1, about 3:1 to about 10:1, about 4:1 to about 30:1, about 4:1 to about 20:1, about 5:1 to about 20:1, about 5:1 to about 15:1, about 10:1 to about 30:1, or about 10:1 to about 15:1.

[16] Any of the preceding methods, further comprising, prior to step (i), contacting the nickel-molybdenum catalyst with an inert gas at a purge temperature of about 235° C. or less.

[17] the inert gas comprises nitrogen; The method according to

[16] , wherein the purge temperature is about 60°C to about 200°C, about 80°C to about 180°C, or about 110°C to about 160°C.

[18] the yield relative to the mercaptan compound is at least about 50 mol%, at least about 70 mol%, at least about 80 mol%, at least about 90 mol%, about 80 to about 99 mol%, or about 90 to about 98 mol%, and / or Any of the above-mentioned methods, wherein the conversion rate of the alcohol compound or the olefin compound is at least about 50 mol%, at least about 80 mol%, at least about 90 mol%, at least about 95 mol%, about 80 to about 99 mol%, about 90 to about 98 mol%, or about 95 to 100 mol%.

[19] The method of any of the preceding claims, wherein the reaction mixture comprises no more than about 10 mol%, no more than about 8 mol%, no more than about 5 mol%, or no more than about 3 mol% non-mercaptan reaction products.

[20] Any of the aforementioned methods, wherein the selectivity of the mercaptan compounds is at least about 75 mol%, at least about 80 mol%, at least about 85 mol%, at least about 90 mol%, or at least about 95 mol%, based on the total amount of the mercaptan compounds in the reaction mixture.

[21] Any of the preceding methods further comprising separating said mercaptan compounds from said reaction mixture to form a product stream comprising said mercaptan compounds.

[22] Any of the preceding methods, wherein after step (ii), unreacted alcohol compound or unreacted olefin compound is recycled.

[23] the nickel-molybdenum catalyst and the supported sulfur-containing catalyst independently comprise: a solid support; about 1 to about 5 wt.%, about 1 to about 3 wt.%, about 2 to about 5 wt.%, about 2 to about 4 wt.%, or about 2.5 to about 4 wt.% nickel; The method according to any of the preceding claims, comprising about 4 to about 18 wt.%, about 4 to about 16 wt.%, about 10 to about 15 wt.%, about 11 to about 17 wt.%, or about 13 to about 16 wt.% molybdenum.

[24] Any of the preceding methods, wherein the nickel-molybdenum catalyst and the supported sulfur-containing catalyst independently comprise no more than about 3 wt.%, no more than about 2.5 wt.%, no more than about 2 wt.%, no more than about 1 wt.%, or no more than about 0.5 wt.% carbon.

[25] The nickel-molybdenum catalyst and the supported sulfur-containing catalyst are independently mixed for about 75 to about 400 m 2 / g, about 100~350m 2 / g, about 100~300m 2 / g, approx. 125~275m 2 / g, about 150~375m 2 / g, or about 150 to about 250 m 2 The method of any preceding claim, wherein the surface is characterized by a BET surface area of ​​1000 nm / g.

[26] %.

[27] The method according to any one of

[23] to

[26] , wherein the solid support comprises silica, alumina, magnesia, boria, titania, zirconia, zeolite, mixed oxides thereof, or mixtures thereof.

Claims

1. 1. A method for producing a mercaptan compound, the method comprising: (i) A nickel-molybdenum catalyst is sulfided at a sulfiding temperature of 235°C or less by H ２ S to form a supported sulfur-containing catalyst; (ii) an alcohol compound and H ２ and contacting S with the supported sulfur-containing catalyst to form a reaction mixture comprising the mercaptan compound; Step (i) is a step of subjecting the nickel-molybdenum catalyst to an inlet sulfiding temperature of 10°C to 90°C. ２ contacting the compound with S; The method, wherein the mercaptan compound is ethyl mercaptan, isopropyl mercaptan, or sec-butyl mercaptan.

2. 1. A method for producing a mercaptan compound, the method comprising: (i) A nickel-molybdenum catalyst is sulfided at a sulfiding temperature of 235°C or less by H ２ S to form a supported sulfur-containing catalyst; (ii) an olefin compound and H ２ and contacting S with the supported sulfur-containing catalyst to form a reaction mixture comprising the mercaptan compound; Step (i) is a step of subjecting the nickel-molybdenum catalyst to an inlet sulfiding temperature of 10°C to 90°C. ２ contacting the compound with S; The method, wherein the mercaptan compound is ethyl mercaptan, isopropyl mercaptan, or sec-butyl mercaptan.

3. The mercaptan compound is represented by the formula (A): R １ -SH, The alcohol compound is represented by the formula (B): R １ having —OH, R １ But C １ ~C ４ a substituted or unsubstituted straight-chain or branched alkyl group, In some cases, R １ and R ２ The method of claim 1 , wherein is a straight chain alkyl group or a branched alkyl group.

4. The mercaptan compound is represented by the formula (C): R ２ -SH, The olefin compound is represented by the formula C═C or the formula (D): R １ -C=C, R １ But C １ ~C ４ a substituted or unsubstituted straight-chain or branched alkyl group, R ２ But C ３ ~C ４ a substituted or unsubstituted straight-chain or branched alkyl group, In some cases, R １ and R ２ The method of claim 2 , wherein is a straight chain alkyl group or a branched alkyl group.

5. R １ is C １ ~C ４ is an alkyl group, or R １ The method according to any one of claims 3 to 4, wherein is an ethyl group, a propyl group, or a butyl group.

6. 10. The method of claim 1, wherein the alcohol compound comprises ethanol, propanol, butanol, or any combination thereof.

7. 3. The method of claim 2, wherein the olefinic compound comprises ethylene, propylene, butene, or any combination thereof.

8. Step (i) is a step of subjecting the nickel-molybdenum catalyst to inlet sulfurization at an inlet sulfurization temperature of 20°C to 80°C, 20°C to 60°C, or 35°C to 70°C. ２ contacting the compound with S; Or, Step (i) a sulfurization temperature of 60°C to 235°C, 60°C to 200°C, 40°C to 100°C, 80°C to 225°C, 80°C to 180°C, 110°C to 235°C, 110°C to 200°C, or 110°C to 160°C; and 8. The process of any one of claims 1 to 7, wherein the process is carried out at a sulfiding pressure of 50 to 250 psig (0.35 to 1.72 MPa), 50 to 200 psig (0.35 to 1.38 MPa), 100 to 250 psig (0.689 to 1.72 MPa), 100 to 200 psig (0.689 to 1.38 MPa), or 100 to 150 psig (0.689 to 1.03 MPa).

9. Step (ii) is a temperature in the range of 100°C to 300°C, 125°C to 275°C, 175°C to 275°C, 175°C to 250°C, 200°C to 300°C, 200°C to 275°C, or 200°C to 250°C; pressures within the ranges of 50-1000 psig (0.35-6.895 MPa), 50-500 psig (0.35-3.45 MPa), 100-800 psig (0.689-5.52 MPa), 150-450 psig (1.03-3.10 MPa), 200-450 psig (1.39-3.10 MPa), 200-350 psig (1.39-2.41 MPa), or 300-450 psig (2.07-3.10 MPa); and 9. The method of any one of claims 1 to 8, carried out at a WHSV in the range of 0.01 to 5, 0.02 to 3, 0.05 to 1.5, 0.1 to 4, 0.2 to 3, 0.2 to 1.2, 0.2 to 1, 0.5 to 2, or 0.5 to 1.

10. Step (ii) is a step of reacting the alcohol compound or the olefin compound and H ２ 10. The process of any one of claims 1 to 9, comprising contacting S with a fixed bed of said supported sulfur-containing catalyst.

11. H ２ S: alcohol compound or H ２ 11. The process of any one of claims 1 to 10, wherein the molar ratio of S:olefinic compound is in the range of 3:1 to 50:1, 3:1 to 18:1, 3:1 to 10:1, 4:1 to 30:1, 4:1 to 20:1, 5:1 to 20:1, 5:1 to 15:1, 10:1 to 30:1, or 10:1 to 15:

1.

12. prior to step (i), further comprising contacting the nickel-molybdenum catalyst with an inert gas at a purge temperature of 235° C. or less; 12. The method of any one of claims 1 to 11, wherein optionally the inert gas comprises nitrogen and the purging temperature is from 60°C to 200°C, from 80°C to 180°C, or from 110°C to 160°C.

13. a yield based on the mercaptan compound of at least 50 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, 80 to 99 mol%, or 90 to 98 mol%; and / or The method according to any one of claims 1 to 12, wherein the conversion of the alcohol compound or the olefin compound is at least 50 mol%, at least 80 mol%, at least 90 mol%, at least 95 mol%, 80 to 99 mol%, 90 to 98 mol%, or 95 to 100 mol%.

14. the reaction mixture comprises no more than 10 mol%, no more than 8 mol%, no more than 5 mol%, or no more than 3 mol% of non-mercaptan reaction products; and / or the selectivity of the mercaptan compounds is at least 75 mol%, at least 80 mol%, at least 85 mol%, at least 90 mol%, or at least 95 mol%, based on the total amount of the mercaptan compounds in the reaction mixture; and / or and / or further comprising separating the mercaptan compounds from the reaction mixture to form a product stream comprising the mercaptan compounds. The method according to any one of claims 1 to 13, wherein after step (ii) any unreacted alcohol compound or unreacted olefin compound is recycled.

15. the nickel-molybdenum catalyst and the supported sulfur-containing catalyst independently comprise: a solid support; 1 to 5 wt. %, 1 to 3 wt. %, 2 to 5 wt. %, 2 to 4 wt. %, or 2.5 to 4 wt. % nickel; 4-18 wt.%, 4-16 wt.%, 10-15 wt.%, 11-17 wt.%, or 13-16 wt.% molybdenum, optionally wherein the solid support comprises silica, alumina, magnesia, boria, titania, zirconia, zeolite, mixed oxides thereof, or mixtures thereof; and / or the nickel-molybdenum catalyst and the supported sulfur-containing catalyst independently contain no more than 3 wt.%, no more than 2.5 wt.%, no more than 2 wt.%, no more than 1 wt.%, or no more than 0.5 wt.% carbon; and / or The nickel-molybdenum catalyst and the supported sulfur-containing catalyst are independently from each other in a range of from 75 to 400 m ２ / g, 100-350m ２ / g, 100-300m ２ / g, 125-275m ２ / g, 150-375m ２ / g, or 150-250m ２ / g BET surface area and / or 15. The method of any one of claims 1 to 14, wherein the supported sulfur-containing catalyst comprises 3 to 18 wt.%, 4 to 17 wt.%, 5 to 15 wt.%, or 7 to 13 wt.% sulfur.

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