GB522840A - Manufacture of surface-active compounds - Google Patents

Abstract

522,840. Making dispersions. DU PONT DE NEMOURS & CO., E. I. Dec. 19, 1938, No. 36927. Convention date, Dec. 18, 1937. [Class 1 (i)] [Also in Group IV] Secondary alkyl monosulphonic acids and their salts having the formula R.CH.R<SP>1</SP> in X which X is a sulphonic acid or sulphonate group and R and R<SP>1</SP> are alkyl groups each of which contains at least two carbon atoms, and are such that the group R.C.R<SP>1</SP> contains 10-16 carbon atoms at least 10 of which form a straight chain, are prepared by treating the corresponding mercaptans with an oxidizing agent, or the corresponding halide or sodium sulphate with sodium sulphite. The products are stated to be dispersing agents. In examples: (1) sodium pentadecyl-8-sulphate is treated with sodium sulphite in the presence of a small quantity of aniline and sodium dihydrogenphosphate to give sodium pentadecyl-8-sulphonate ; (2) sodium pentadecyl-4-sulphonate is prepared by treating sodium pentadecyl-4-sulphate with sodium sulphite ; (3) pentadecyl-8-mercaptan is oxidized with nitric acid; the product is neutralized, dissolved in aqueous methanol and extracted with ether to remove impurities. The use of pentadecyl-3-, 4-, 5-, 6- and 7- mercaptan, tridecyl - 7 - mercaptan, dodecyl - 6 - mercaptan, 7 - ethyl - 2 - methylundecyl - 4 - mercaptan, 3 : 9 - diethylundecyl - 6 - mercap - tan, 3 - ethyldecyl - 6 - mercaptan, undecyl - 4 - mercaptan and 2 - methylundecyl - 5 - mercap - tan is mentioned. For neutralizing the sulphonic acids potassium, ammonium, calcium and magnesium hydroxides and dimethylamine, ethylamine, diethanolamine, butylantine, glucamine, methylglucamine, pyridine, piperidine, cyclohexylamine and toluidine may be used. The Specification as open to inspection under Sect. 91 comprises also the use of mixtures of secondary mercaptans and includes an example in which. mercaptans prepared from chlorinated cetane are used as starting material, The oxidation of thiosulphuric acid esters, the treatment of secondary alcohols with methanedisulphonic acid and the sulphonation of secondary olefines are further methods which are described. This subject-matter does not appear in the Specification as accepted.