DETERMINATION OF AROMATIC SULFONIC-ACIDS IN INDUSTRIAL-WASTE WATER BYION-PAIR CHROMATOGRAPHY

A method for the identification and quantification of aromatic sulfoni c acids in industrial waste water has been developed. The preparation of the samples comprises a clean-up step and an enrichment step, utili zing i) reversed-phase extraction and ii) ion-pair solid phase extract ion. The aromatic sulfonic acids are separated by ion-pair chromatogra phy with diode-array detection. An advantage of the developed ion-pair chromatographic method is the separation of linear alkylbenzenesulfon ic acids (LAS), lignosulfonic acids and aromatic sulfonic acids in one chromatographic run. Also described is an optimized clean-up procedur e for collected fractions of a preparative chromatographic run to iden tify monosulfonic acids with GC/MS after methylation. The detection li mits for aromatic sulfonic acids in industrial waste waters are at the mug/1 level.