GB703826A - Improvements in or relating to catalysts for use in the treatment of unsaturated fatty acids or their derivatives - Google Patents

Abstract

In the preparation of a nickel catalyst on a silicon dioxide-containing carrier, for use in the isomerization of unsaturated fatty acids or their derivatives, a nickel compound is reduced and a minor proportion of selenium or tellurium (preferably 4-12 per cent. based on the weight of nickel) is incorporated in the nickel compound before reducing it. Sodium carbonate solution is added to nickel nitrate or sulphate solution in the presence of kieselguhr and the precipitate is filtered off and dried; alternatively a solution of sodium silicate may be added to the nickel salt solution. The selenium or tellurium in elementary form or as a selenite, selenate, tellurite, or tellurate, is added before or during precipitation, or to the filter cake before or after drying. From 1-2 per cent. of sulphur, based on the weight of nickel, may also be included in the catalyst. Reduction is effected at 475 DEG C. in a stream of p hydrogen. Substances which may be treated with the catalysts include oleic acid, linseed oil fatty acids, and their methyl and ethyl esters, and oils containing linoleic and linolenic acids, for example linseed oil, soyabean oil, tobacco seed oil, safflower oil, sunflower seed oil, and poppy seed oil. Treatment is carried out at 80 DEG -220 DEG C. for five minutes to ten hours, and results in shifting and conjugation of double bonds, and conversion of cis-isomers to the transform. The oil products have increased melting points and quickly polymerize and dry into non-tacky waterproof films.