Patent GB-464951-A (GB)
Title: A process for the production of valuable products from mercaptans and unsaturated hydrocarbons
IPC: C07C5/03
Filed: 1936-03-13
Abstract: Thioethers and/or saturated hydrocarbons are produced by reacting a hydrocarbon containing an olefinic linkage between two carbon atoms with a mercaptan at an elevated temperature and under superatmospheric pressure.  Disulphides also appear to be formed with the saturated hydrocarbons.  Thioether formation is favoured by employing the reactants in the gaseous phase, at temperatures of from 35 to 200 DEG  C., and by reacting at least 1 mol. olefine with 1 mol. mercaptan.  Hydrocarbon formation is favoured by operating at materially above 200 DEG  C. up to 500 DEG  C., and in the liquid phase, preferably by employing the higher boiling mercaptans and/or olefines, e.g. olefines containing at least six carbon atoms and especially those possessing a tertiary carbon atom, and by employing excess mercaptan.  Under the same temperature and pressure conditions, hydrocarbon formation usually requires a longer reaction time than is necessary for thioether formation.  A list of suitable olefines is given, and includes such compounds as ethylene and its homologues, analogues such as phenyl and naphthyl ethylene, &c., polyolefines such as divinyl, diallyl, &c., and olefine polymers, particularly those containing at least six carbon atoms and a branched chain such as diisobutylene &c.  Mixtures of unsaturated hydrocarbons may be used.  Reaction may be effected in the presence of paraffins, halogenated hydrocarbons, oils, inert gases or other unreactive substances.  Technical olefine-containing mixtures may be treated without separation of the olefines.  Such mixtures may be obtained by the pyrogenesis of petroleum, petroleum products, shale oil, &c., or by the destructive distillation and/or hydrogenation of coal, peat, pitches, tars, asphalts, &c.  The mixtures may be fractionated into cuts containing the same number of carbon atoms, the butane-butene cut being specified.  The mercaptan may contain one or more --SH groups, and be of alkyl aralkyl, alkenyl, aralkenyl or aryl character.  A list is given.  Reference is also made to the production of thioethers containing alicyclic and heterocyclic radicals.  The reagents should be initially dried, and the reaction is preferably carried out in the presence of water-binding agents, for example, carboxylic acid anhydrides, a list being given.  The reaction is carried out in the presence or absence of catalysts. Generally, when thioethers are to be produced, the reaction is accelerated by the presence of metals or metal compounds, particularly metal sulphides.  Sulphides of the following metals are specified: calcium, beryllium, zinc, magnesium, strontium, barium, aluminium, chromium, zirconium, tin, copper, thallium, vanadium, molybdenum, tungsten, arsenic, antimony, platinum, nickel, iron, cobalt.  The sulphides are produced by treating the metals or their oxides or hydroxides with sulphidizing agents, or with hydrogen sulphide before or during the reaction, or by thermal decomposition of the thio-salts.  The catalyst may be employed in powder, granule or pellet form, or may be precipitated on pumice, silica gel, kieselguhr or charcoal.  A film of metal sulphide may be deposited on the reaction vessel by treatment of the surface with hydrogen sulphide or a solution of a sulphide or hydrosulphide.  The pressures employed, which may be increased by the introduction of an inert liquid or gas, should not exceed about 250 atms.  The operation may be carried out in a batch, intermittent, or continuous manner.  The water binding agent and/or catalyst may be added before, during or after introduction of the reactants into the reaction vessel. Agitation of the reaction mixture is desirable.  Several examples are given. The process is applicable to the purification of liquid mixtures containing mercaptans and/or unsaturated hydrocarbons. Thus, a liquid mixture of hydrocarbons containing mercaptans is admixed with an olefine and the mercaptans converted to thioethers which are removed by treatment with sulphuric acid or liquid ammonia. Liquids specified are mineral oils, pressure distillates, gasoline and kerosene.  The thioethers are solvents for rubber, resins such as abietic acid, paracumarone, meta- and para-cresol sulphur chloride resins, and petroleum resins.  Mixtures with aliphatic alcohols are solvents for cellulose esters.  They are useful as constituents of insecticides and fly-repellents, and as intermediates in the preparation of pyroxylin and saporific sulphones.  The higher saturated hydrocarbons, particularly those of branched chain structure, are useful as fuels, lubricants, solvents, and for resin production.ALSO:Thioethers and/or saturated hydrocarbons are produced by reacting a hydrocarbon containing an olefinic linkage between two carbon atoms with a mercaptan at an elevated temperature and under superatmospheric pressure.  The reaction is carried out in the presence or absence of catalysts.  Generally when thioethers are to be produced the reaction is accelerated by the presence of metals or metal compounds, particularly metal sulphides. Sulphides of the following metals are specified:--calcium, beryllium, zinc, magnesium, strontium, barium, aluminium, chromium, zirconium, tin, copper, thallium, vanadium, molybdenum, tungsten, arsenic, antimony, platinum, nickel iron, cobalt.  The sulphides are produced by treating the metals or their oxides or hydroxides with sulphidizing agents, or with hydrogen sulphide before or during the reaction, or by thermal decomposition of the thio-salts.  The catalyst may be employed in powder, granule or pellet form, or may be precipitated on pumice, silica gel, kieselguhr or charcoal.  A film of metal sulphide may be deposited on the reaction vessel by treatment of the surface with hydrogen sulphide or a solution of a sulphide or hydrosulphide. Hydrocarbon formation is favoured by operating at materially above 200 to 500 DEG  C. and in the liquid phase, preferably by employing the higher boiling mercaptans and/or olefines, e.g. olefines containing at least six carbon atoms and especially those possessing a tertiary carbon atom, and by employing excess mercaptan.  Under the same temperature and pressure conditions, hydrocarbon formation usually requires a longer reaction time than is necessary for thioether formation.  A list of suitable olefines is given, and includes such compounds as ethylene and its homologues, analogues such as phenyl and naphthyl ethylene, &c., polyolefines such as divinyl, diallyl &c., and olefine polymers, particularly those containing at least six carbon atoms and a branched chain such as diisobutylene, &c. Mixtures of unsaturated hydrocarbons may be used. Reaction may be effected in the presence of paraffins, halogenated hydrocarbons, oils, inert gases or other unreactive substances. Technical olefine-containing mixtures may be treated without separation of the olefines.  Such mixtures may be obtained by the pyrogenesis of petroleum, petroleum products, shale oil, &c., or by the destructive distillation and/or hydrogenation of coal, peat, pitches, tars, asphalts &c.  The mixtures may be fractionated into cuts containing the same number of carbon atoms, the butanebutene cut being specified.  The mercaptan may contain one or more --SH groups, and be of alkyl, aralkyl, alkyenyl aralkenyl or aryl character.  A list is given.  The reagents should be initially dried, and the reaction is preferably carried out in the presence of water-binding agents, for example, carboxylic acid anhydrides, a list being given. The pressures employed, which may be increased by the introduction of an inert liquid or gas, should not exceed about 250 atms.  The operation may be carried out in a batch, intermittent, or continuous manner.  The water-binding agent and/or catalyst may be added before, during or after introduction of the reactants into the reaction vessel.  Agitation of the reaction mixture is desirable.  Several examples are given. The process is applicable to the purification of liquid mixtures containing mercaptans and/or unsaturated hydrocarbons.  Thus, a liquid mixture of hydrocarbons containing mercaptans is admixed with an olefine and the mercaptans converted to thioethers which are removed by treatment with sulphuric acid or liquid ammonia. Liquids specified are mineral oils, pressure distillates, gasoline and kerosene.  The higher saturated hydrocarbons, particularly those of branched chain structure, are useful as fuels, lubricants, solvents and for resin production.