| 摘要 |
1,184,377. Preparation of methylchloroform. UGINE KUHLMANN. 17 July, 1967 [20 July, 1966], No. 32827/67. Heading C2C. Methylchloroform is prepared by passing ethylene and HCl into a first reactor in the presence of a hydrochlorination catalyst of the Friedel-Crafts type, to form a gaseous mixture comprising ethyl chloride, introducing the latter with chlorine and a diluent gas into a cooled reactor having a source of actinic light, the molar ratio of Cl 2 : C 2 H 5 Cl being from 1: 1 to 6: 1, the temperature being 25-200‹ C. and reaction period 1-30 seconds, the methylchloroform formed being separated from the diluent, unconverted reactants and from the more volatile and/or less volatile chlorinated byproducts and the required quantity of the HC1 and of diluent and other products being recycled to the first reactor and photochemical reactor respectively as required. The pressure in the two reactors is preferably the same i.e. 1 atmos. up to 10 kg/cm.<SP>2</SP>. The methylchloroform may be extracted from the reaction mixture by washing with a heavy organic solvent, e.g. hexachlorobutadiene, to give a solution which may be distilled to yield solvent, by-products more volatile then CH 3 Cl 3 and methyl-chloroform respectively. Alternatively the reaction mixture may be compressed and cooled to give uncondensed gas consisting of HCl and impure methylohloroform which may be purified by distillation. In the example the catalyst in the first reactor was AlCl 3 and the diluent gas in the photochemical stage was HC1. |
