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United States Patent (19) 11 Patent Number: 4,965,236 Roberts 45 Date of Patent: Oct

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United States Patent (19) 11 Patent Number: 4,965,236 Roberts 45 Date of Patent: Oct United States Patent (19) 11 Patent Number: 4,965,236 Roberts 45 Date of Patent: Oct. 23, 1990 (54) PROCESS FOR PRODUCING A CATALYST 3,867,312 2/1975 Stephens ............................. 252/462 4,019,978 4/1977 Miller et al. ........................ 208/213 75 Inventor: John S. Roberts, Bartlesville, Okla. 4,059,636 11/1977 Kubicek. ... 260/609 D 4,066,572 1/1978 Choca ................................. 252/437 (73) Assignee: Phillips Petroleum Company, 4,080,311 3/1978 Kehl. ... 252/437 Bartlesville, Okla. 4,145,352 3/1979 Kubicek ... ... 260/326.82 4,146,574 3/1979 Onoda et al. ....................... 423/299 21) Appl. No.: 335,651 4,297,242 10/1981 Hensley, Jr. et al. ... 252/439 22 Fied: Apr. 10, 1989 4,444,906 4/1984 Callahan et al. ......... ... 502/211 4,522,934 6/1985 Shum et al.......................... 502/209 Related U.S. Application Data Primary Examiner-W. J. Shine 60 Division of Ser. No. 908,558, Sep. 18, 1986, Pat. No. Attorney, Agent, or Firm-J. D. Brown 4,837,192, which is a continuation-in-part of Ser. No. 742,818, Jun. 10, 1985, abandoned, which is a division 57 ABSTRACT of Ser. No. 542,960, Oct. 18, 1983, Pat. No. 4,537,994. Interchange reactions between organosulfides and ner (51) Int. Cl. ......................... B01J 27/18; B01J 27/19 captans are promoted by the use of catalysts containing (52) U.S. C. .................................................... 502/211 Group VIB oxides. The preferred catalysts are sup Field of Search ................................ 502/210, 211 ported phospho Group VIB oxide acids, such as phos (58 photungstic acid and phosphomolybdic acid. The pre (56) References Cited ferred supports are moderately acidic supports that U.S. PATENT DOCUMENTS contain aluminum, such as zinc aluminate and aluminum 2,440,236 4/1948 Stirton ............................ 502/208 X phosphate. 2,441,297 5/1948 Stirton .......... ... 502/208 X 2,726,195 12/1955 Fleck et al. ..................... 502/211 X 11 Claims, No Drawings 4,965,236 1. 2 tions in which at least one organic moiety of a diorgano PROCESS FOR PRODUCING A CATALYST sulfide is replaced by an organic moiety from a mercap tan. This is a divisional of copending application Ser. No. The general reaction scheme can be represented by: 908,558 filed Sept. 18, 1986 now U.S. Pat. No. 4,837,192, patented June 6, 1989 which is a continuation R - S - R--R'SH-R - S - R --RSH. in part of application Ser. No. 742,818 filed June 10, 1985 abandoned, which is a divisional of Ser. No. In the above formulas, R and R' are independently 542,960, filed Oct. 18, 1983 now U.S. Pat. No. 4,537,994, selected from the group consisting of alkyl, cycloalkyl, patented Aug. 27, 1985. 10 aromatic, alklaryl, arylalkyl, straight chain or branched chain groups, with the R's being the same or different in BACKGROUND the same molecule. Generally, the R and R' groups are Organosulfides are useful in a number of ways. Many selected so that sulfides and mercaptains to be used con organo sulfides are solvents, plasticizers and processing tain from about 2 to about 40 carbon atoms per mole aids for various other organic materials. Some dior 15 cule, preferably from about 2 to about 16. ganosulfides, such as phenylpropylsulfide, are useful as Sulfides useful in the invention are exemplified by the corrosion inhibitors, hair growth stimulators, and as sulfides disclosed in U.S. Pat. No. 4,059,636, the disclo extractants for noble metals. sure of which is hereby incorporated by reference. The preparation of organosulfides using mercaptains The organic sulfides employed in the practice of this as reactants involves a metathesis, or interchange, reac 20 invention include those of general formula R-S-R; tion between the organic radical of the mercaptan and wherein the R groups are as defined above. one or more of the organic substituents of an organosul Examples of useful sulfides include dimethyl sulfide, fide reactant. Such reactions generally have low con diethyl sulfide, diisopropyl sulfide, di-n-butyl sulfide, version and selectivity values. di-n-octyl sulfide, di-n-dodecyl sulfide, di-n-eicosyl sul INVENTION 25 fide, methyl ethyl sulfide, n-pentyl-n-heptyl sulfide, It has been discovered that the reaction of certain dicyclohexyl sulfide, bis(4-methylcyclo-hexyl) sulfide, organosulfides with mercaptains to yield substitution, or diphenyl sulfide, di-p-tolyl sulfide, bis(p-n-hexylphenyl) metathesis, products, can be more effectively carried sulfide, dibenzyl sulfide, and the like. Mixtures of sul out in the presence of Group VIB oxides, such as sup 30 fides as well as mixtures of sulfide with other inert com ported phosphotungstic or phosphomolybdic acid cata ponents are feedstocks within the scope of this inven lysts. tion. In one embodiment, alkyl aryl sulides are prepared Useful mercaptains correspond to the sulfides dis from thiophenol by reacting it with dialkylsulfides over cussed above. That is, they are the formula R'SH in an alumino phosphotungstic acid catalyst. For example, 35 which R" is independently selected from the groups of when a mixture of a di-n-propyl sulfide and thiophenol moieties defined above. is passed over a hot (580 F) catalyst prepared from Examples of useful mercaptains include alkylthiols, aluminum phosphate and phosphotungstic acid, a 12% e.g., methyl mercaptain (methanethiol), ethyl mercaptain sulfide conversion results in a product having a 90.5% (ethanethiol), octyl mercaptain (octanethiol) and the selectivity to phenyl n-propylsulfide. like; aromatic thiol, e.g., phenyl mercaptan (thio OBJECTS OF THE INVENTION phenol), napthyl mercaptans (napthylene thiols), and It is one object of the present invention to provide the like. Phenyl mercaptan and alkylphenyi mercaptans catalysts useful for assisting in the reaction of organic are preferred. Substituted forms of these mercaptans, sulfides with mercaptains to yield metathesis or inter i.e., compound containing branched chain and/or non change products. 45 functional substituents are operable. Mixtures of mer It is another object of the present invention to pro captain reactants are operable. vide a process for producing these catalysts. While the use of stoichiometric quantities of reactants It is yet another object of the present invention to can be inferred from the above equation, quantities provide a process by which such interchange reactions 50 other than stoichiometric amounts are operable. Gener can be carried out. ally sulfide:mercaptain mole ratios of about 1:1 to about 1:10 with about 1:1.01 to about 1:5 preferred, can be ADVANTAGES used. While the presence of an excess of either reactant The catalysts and processes of the invention have can be tolerated, it is preferred that, when excess reac several advantages over the prior art. Specifically, reac 55 tant is used, it be the mercaptain (thiol) which is present tions carried out in accordance with the invention have in excess. This is primarily because of the relative ease good conversion rates and high selectivities to desired of separation due to high volatility of the mercaptain and products. in part because of economics. Other advantages and aspects of the invention will The use of more than one sulfide and more than one become apparent from a consideration of the following 60 mercaptain in combination is contemplated. description. Catalysts DESCRIPTION OF THE INVENTION The catalysts of the present invention can be used Reactants with or without the support; however, it is preferred The reactants with which the invention are con 65 that the catalyst be a supported catalyst. cerned take part in interchange reactions involving The supported catalysts useful herein are derivatives mercaptans, i.e., thiols or thioalcohols, and sulfides, i.e., of Group VIB oxide components, preferably molybde thioethers. Generally, these reactions involve interac num oxide and tungsten oxide components, and are 4,965,236 3 4. produced by contacting these components with suitable 1 to about 10 moles per mole of Group VIB metal oxide supports. present in the catalyst. Suitable tungsten oxide and molybdenum oxide com The phospho Group VIB acids that are used to pre ponents include phosphotungstic and phosphomolybdic pare the preferred catalysts are readily available, but acid, their hydrates, metal salts, and the like. Mixtures can be prepared by reacting the Group VlBoxide with of molybdenum and tungsten oxide components can be phosphoric acid. employed. The amount of catalyst employed in the instant reac Preferred catalysts are phospho Group VIB oxide tions generally ranges from about 0.01 weight percent acids. Catalysts more preferred are supported phospho to about 1 weight percent based on the weight of the Group VIB oxide acids. The catalysts most preferred 10 total reaction mixture. are supported phosphotungstic or phosphomolybdic The catalyst can be regenerated when necessary by acid catalysts. heating in oxygen and then passing a sulfur compound, When supported, useful support components include such as H2S, over the catalyst at elevated temperature. activated carbon, alumina, aluminum phosphate, zinc A supported catalyst of the present invention is made aluminate, silica alumina, zirconia, silica, thoria, pum 15 by ice, and the like and mixtures of any two or more (a) adding the support material to a solution of Group thereof. The more preferred support is one that has the VIB oxide component in polar diluent; characterstic of being moderately acidic. The moder (b) mixing the material from step (a) for a sufficient ately acidic catalyst supports that are most preferred length of time to allow the Group VIB oxide compo 20 nent to react and impregnate onto the support, thereby contain aluminum, and are preferably zinc aluminate forming a supported catalyst; and aluminium phosphate. It is also preferred that the (c) drying the supported catalyst of step (b) thereby final supported catalyst of the present invention be forming a dried catalyst; and moderately acidic.
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