METHOD FOR PREPARING LIGHT-COLOURED ETHER CARBOXYLIC ACIDS

摘要

The invention concerns a method for preparing ether carboxylic acids or their salts of formula (I) R<1>(OCH2CH2)nOCH2COOX in which R<1> represents an alkyl, alkenyl and/or alkylphenyl group linear or branched with between 6 and 22 carbon atoms; X represents hydrogen of an alkaline metal and n represents numbers ranging between 1 and 10. The preparation of said ether carboxylic acids is carried out by carboxymethylation of ethoxylates of alcohol or of alkylphenol of formula (II) R<1>(OCH2CH2)nOX in which R<1>, X and n have the same meanings as above, with haloacetic acid or its alkaline salts. Said method is characterised in that the reaction is carried out in the presence of reducing agents.