Process for the purification of aqueous sulphosuccinic acid which contains maleic or fumaric acid

摘要

Aqueous sulphosuccinic acid which contains maleic or fumaric acid is purified by adding at least 2.73 parts by weight of potassium permanganate per part by weight of maleic or fumaric acid at a pH of <2 and temperatures from 40 to 95 DEG C, the mixture being subsequently passed through a cation exchanger and concentrated, if appropriate in vacuo. The potassium permanganate serves to completely degrade the maleic or fumaric acid, without simultaneously attacking the sulphosuccinic acid.