A METHOD FOR THE ANALYSIS OF PHENOL AND MONOCHLORINATED AND BROMINATED PHENOLS FROM COMPLEX AQUEOUS SAMPLES

An analytical procedure for the extraction and quantitation of phenol and monochloro- and monobromophenols from complex aqueous samples is described. The method is developed using spiked samples (400 ng/L) of both ultrapure water and final sewage effluent. The potential loss of spiked compounds through adsorption onto particulate matter is eliminated by initially filtering the matrix prior to spiking. Following acidification (pH 2.0), the addition of excess salt increases the ionic strength of the solution and enhances the transfer of phenols from the aqueous phase into the organic extract. Further filtration of the extract following phase separation facilitates the recovery of an emulsion-free extract that is concentrated and cleaned up by alkali back extraction. Final derivatization with pentafluorobenzoyl chloride enhances the response of the gas chromatograph–electron-capture detector, facilitating adequate recoveries down to nanogramper-liter levels. The method is applicable to the recovery of six monosubstituted phenols; extraction efficiencies for individual compounds range from 60 to 82% and have a mean standard deviation of 9.3%. © 1994, Oxford University Press. All rights reserved.