GB633979A - Recovery of alcohols from mixtures containing same - Google Patents

Abstract

The concentration of secondary alcohols of 8 or more carbon atoms in mixtures containing them or their easily hydrolysable derivatives together with hydrocarbons is effected by fractionating said mixtures in the presence of a base to produce a number of cuts so chosen that the boiling point of the highest boiling hydrocarbon or other constituent, if any, is below the boiling point of the lowest boiling boric acid ester which will be formed by esterifying the cut, esterifying these cuts with boric acid while removing water as formed, distilling under reduced pressure at not substantially above 200 DEG C. to concentrate the boric esters, and hydrolysing to recover the higher secondary alcohols. The initial mixtures may be residues from the sulphation of higher olefines such as cracked petroleum wax, to produce secondary alkyl sulphates or the products of sulphation and hydrolysis of such olefins. The initial fractionation may be effected at 20-25 mm. to give fractions of 15-50 DEG boiling range, the base used being an alkali or alkaline earth oxide, hydroxide or carbonate or benzidine. Esterification is effected by heating with boric acid not substantially in excess of the theoretical amount at 80-120 DEG , preferably 96 DEG C., water being removed as by use of entrainers or inert gas. The esterified cuts are distilled under reduced pressure at not more than about 200 DEG C., preferably at 1-5 mm. and below 150 DEG C., if desired with the introduction of a hydrocarbon of intermediate boiling point, or vapours of organic liquids, to facilitate concentration of the esters. These are boiled with water and the alcohols recovered. Examples describe the concentration and recovery of alcohols from C15-17, C10-12, C3-10 and C13-15 hydrocarbon-alcohol cuts of the residue obtained in the production of secondary alkyl sulphates or the crude reaction mixture obtained by sulphation and hydrolysis of olefins.