GB810017A - Improvements in and relating to the manufacture of methyl sulphide and methyl mercaptan - Google Patents

Abstract

Methyl mercaptan is prepared by passing hydrogen sulphide, methanol vapour and methyl sulphide together through a fluid bed of a metal oxide catalyst consisting of activated alumina, thorium oxide, zirconium oxide, uranium oxide, chromium oxide or the blue oxide of molybdenum or tungsten at a temperature between 400 DEG and 450 DEG C. and separating the resulting methyl mercaptan from the methyl sulphide by rectification and recycling the methyl sulphide to the reaction zone. Methyl sulphide is prepared in like manner by passing hydrogen sulphide, methanol vapour and methyl mercaptan through the fluid bed of catalyst at between 400 DEG and 450 DEG C., separating the resulting methyl sulphide from the methyl mercaptan by rectification and recycling the methyl mercaptan to the reaction zone. Examples are given of each process utilizing an illustrated form of apparatus wherein methanol vapour, excess hydrogen sulphide and recycled methyl sulphide or mercaptan are passed into the bottom of a fluid bed of activated alumina catalyst at 400-450 DEG C., the effluent product stream is cooled to strip-out by-product water and any unchanged methanol and then fractionated to separate the methyl sulphide from the methyl mercaptan and one is withdrawn from the system as the desired product and the other is recycled to the reaction zone. Reference has been directed by the Comptroller to Specification 773,697.