GB632820A - Improvements in or relating to the production of organic compounds by chemical transformation of methane or its sulfonated and/or oxygenated derivatives - Google Patents

Abstract

Sulphur trioxide and methane are reacted at 100-450 DEG C. under superatmospheric pressure and one or more of the following separated from the products: methanol, methyl sulphates, methane sulphonic acid and methionic acid, and their methyl esters. Preferably a sulphonation catalyst is used such as a Group 2B metal, particularly mercury, or a sulphate thereof. Pressures are generally below 5000, e.g. 100-2500 p.s.i. Natural gas or other gas consisting mainly of methane with some ethane may be used. Sulphur oxides may be separated from the products for re-use, if necessary after oxidizing the dioxide to trioxide. Condensation or distillation of the products admits of separation thereof or hydrolysis by steam distillation yields methanol or its esters and a residue yielding sulphonic acids. Methane sulphonic acid or its ester may be pyrolyzed at 225-500 DEG C., for example by refluxing at 325 DEG C., with addition of water if required, to give methanol. Disulphonated derivatives of methane may be converted to methanol, for example, by hydrolysis to methane sulphonic acid and sulphuric acid, and pyrolysis of the former. Methanol or dimethyl ether obtained from the reaction products may be subjected to the action of dehydrating and condensing agents such as metallic polyhalides, whose hydrolysis may be suppressed by addition of gaseous halides, such as halides of zinc, cadmium or thorium, particularly zinc chloride. At preferred temperatures of 375-650 DEG C., and pressures below 5000 p.s.i., hydrocarbons of 4 or more carbon atoms including aromatics are obtained. Isobutane or other isoparaffins, and olefins, may be separated and used to produce alkylates or polymers. In examples, methane and sulphur trioxide are reacted alone or in presence of mercury sulphate, at temperatures between 230 DEG and 300 DEG C., and pressures of 820-1350 p.s.i., molar ratios of SO3 : CH4 being from 0.59 to 10. Methanol obtained by hydrolysis of the products is heated with zinc chloride to give branched lower hydrocarbons, and hexamethylbenzene. The Specification as open to inspection under Sect. 91 comprises also the pyrolysis of methane sulphonic acid and the dehydration, condensation of methanol or dimethyl ether, however said initial materials are prepared, and includes additional examples thereof. This subject-matter does not appear in the Specification as accepted.