| abstract |
A process for improving the color and purity of dark-colored potassium or magnesium alkyl ester sulfonate surfactant compositions, and particularly alpha-sulfo fatty acid methyl ester compositions, without the need for bleaching or other process steps. The process comprises the steps of (1) forming a mixture comprising (i) an alkyl ester sulfonate surfactant composition containing impurities including dark-colored impurities, organic and inorganic salts, and disalts, and (ii) water, and (2) separating the ester sulfonate surfactant from the mixture. The process may further comprise step (3) recovering the alkyl ester sulfonate surfactant. Methyl ester sulfonate surfactant compositions are most preferred. After processing in accordance with the invention, the alkyl ester sulfonate surfactant composition has improved color, purity, and odor properties. |