PROCESS FOR PRODUCING PARAFFINE-SULFONIC ACIDS

摘要

The invention is concerned with an improved process for preparing paraffin-sulfonic acids containing from 10 to 20 carbon atoms, as well as their salts. The process comprises the initial reaction of sulfo-oxidation of the concerned mixture of n-paraffins, the removal of unreacted n-paraffins from the reaction mixture, the removal of the excess of SO2 from said mixture, and the removal from the reaction mixture of the therein formed sulfuric acid, with the simultaneous recovery of the end product. After the removal of SO2, to the reaction mixture hydrogen peroxide is added and the so obtained solution is submitted to one treatment selected from among the following treatments: (a) addition of an alcohol with a number of carbon atoms comprised within the range of from 4 to 8; (b) heating up to a temperature comprised within the range of from 50 to 150 DEG C and vacuum distillation under a residual pressure comprised within the range of from 5 to 500 mmHg until at least 60% of contained water is distilled off; (c) addition of an either aliphatic or cycloaliphatic paraffin with a number of carbon atoms comprised within the range of from 6 to 8 and distillation of the resulting azeotropic mixture at a temperature comprised within the range of from 20 to 120 DEG C. e