DETERMINATION OF ALKYL SULFATE SURFACTANTS IN NATURAL-WATERS

An analytical technique was developed to monitor alkyl sulfate (AS) surfactants in natural water samples and determine AS removal during wastewater treatment The method utilizes a reverse-phase extraction column followed by strong anionic and cationic exchange column cleanup steps. AS are then derivatized with N,O-bis(trimethylsilyl)trifluoroacetimide with 1 % trichloromethylsilane and analyzed by GC/FID as trimethylsilyl ethers. Total AS concentrations in wastewater varied as a function of time and were correlated with expected consumer use patterns of AS-containing products. Flow-weighted average total AS concentrations in influent wastewater were at least 2.4 times lower than expected based on mass balance predictions and were probably due to AS loss during waste-water conveyance. Removal of AS at two trickling filter treatment plants exceeded 90 %. AS was not detected in the receiving streams monitored.