GB794700A - Stabilisation of chlorinated hydrocarbons - Google Patents

Abstract

794,700. Stabilization of chlorinated hydrocarbons. DU PONT DE NEMOURS & CO., E.I. Sept. 18, 1956, No. 28518/56. Class 2 (3). The invention comprises a method of inhibiting the accumulation of acid in a chlorinated hydrocarbon by incorporating in the chlorinated hydrocarbon a basic amine and an epoxide, and the chlorinated hydrocarbons so treated. Preferably the amounts of amine and epoxide are respectively 0.001-0.2 and 0.01- 5.0 per cent by weight of the amount of chlorinated hydrocarbon treated, and the latter generally exceeds the former. In examples, as additives to trichlorethylene are used: trimethylamine with butylene oxide, with previous refluxing of the trichlorethylene and with refluxing of the stabilized composition; triethylamine and cyclohexene oxide are also used, the composition being refluxed and tested; iron powder may be present in the chlorinated hydrocarbon in some circumstances and the additives have the same beneficial effect on the solvent; other combinations of amine and epoxide specified include #-picoline and epichlorhydrin, pyridine and epichlorhydrin, added to trichlorethylene containing a proportion of cutting oil, butylene oxide with aniline and pyridine, diisopropylamine and cyclohexene oxide, diisopropylamine and butylene oxide, and generally epoxides of the formula: where the two carbon atoms each form part of an aliphatic chain, preferably of not more than 8 carbon atoms. Other known additives may be included, e.g. N-methyl pyrrol and ethyl acetate. More than one amine and/or more than one,epoxide may be used. Perchlorethylene, having similar use in de-greasing metals, is also specified as requiring similar stabilization.