Patent GB-323748-A (GB)
Title: Improved process for absorbing ethylene or its homologues by means of sulphuric acid
IPC: C07C29/06
Filed: 1928-07-09
Abstract: 323,748. Elkington, H. D., (Naamlooze Vennootschap de Bataafsche Petroleum Maatschappij). July 9, 1928. Olefines such as ethylene, its homologues or their polymerization products are absorbed in strong acids such as sulphuric acid, phosphoric acid, with or without the addition of strong organic acids in the presence of one or more metallic-cyano complexes as catalysts, illustrated by the acids, ferricyanic acid or ferrocyanic acid or by salts, compounds or addition compounds which can be regarded as being derived therefrom. By hydrolysis of the sulphates formed, ethyl alcohol, isopropyl alcohol, butyl alcohol &c. and esters or ethers may be prepared. Ferricyanic acid or ferrocyanic acid, cobalticyanic acid, cobalticobaltocyanic acid, plratinocyanic acid, chromicyanic acid or salts of these acids or compounds derived from said acids or from cobaltocyanic acid by substituting one or more atoms or groups by other atoms or organic or inorganic radicles or groups or compounds derived from the above acids or compounds by the addition of organic or inorganic compounds may be employed as catalysts. Cyanic acids having more than one metallic atom in the nucleus such as acids of the formula H8Fe2(CN)12' H6Fe2(CN)12 or salts or compounds derived from said acids may sometimes be used. Such acids are formed by condensation of the complex cyanides having one nucleus. The catalysts specified above may be added together with froth forming, scum forming or emulsion forming substances and may be added in a finely divided state or dissolved or dispersed in suitable liquids. The olefines may be obtained from natural gas or gases formed when distilling or cracking petroleum or by destructive hydrogenation of carbonaceous materials. The absorption may be carried out under increased or reduced pressure and if two or more olefines are employed a separation may be effected by passing them through sulphuric acid of gradually in. creasing strength. The olefines may be dissolved in suitable solvents such as gas oil previously treated with sulphuric acid, or may be introduced through small orifices into the acid which may be agitated. The following are specified as examples of suitable compounds :-Sodium nitroprusside, acetone sodium nitroprusside, sodium nitrile prusside, sodium nitroprusside thiocyanic acid, # ferricyanides sodium ferripentacyanicammine, sodium ferripentacyanic nitrosothiocarbamide, benzonitrilferricyanic acid, sodium prussonitrite, sodium ferropentacyanicamine, sodium ferropentacyanic carbonyl, sodiumprussosulphite, sodiumprussoarsenite, sulphonic ferrocyanic acid which may be obtained by heating potassium ferrocyanide with concentrated sulphuric acid at elevated temperature, or addition compounds with organic compounds such as benzonitrile ferrocyanic acid, or carbonyl cobaltocyanic acid. Examples are given of the absorbtion of propylene using potassium ferricyanide, sulphonic ferrocyanic acid, acetone sodium nitroprusside, # ferricyanides, sodium ferropentacyanic carbonyl, barium platinocyanide, tetraethylferrocyanide, diethylnitroprusside, potassium ferrocyanide as catalysts, of ethylene using sulphonic ferrocyanic acid, tetraethyl ferrocyanide, potassiumcarbonyl-cobaltocyanide and of alpha-butylene using potassium ferrocyanide, and ferrocyanic acid as catalysts.