On-line microdialysis-high-performance liquid chromatographic determination of aniline and 2-chloroaniline in polymer industrial wastewater

Determination of aniline and 2-chloroaniline in polymer industrial wastewat er was examined using high-performance liquid chromatography with on-line m icrodialysis. After dilution, aniline and 2-chloroaniline in the sample wer e diffused through a cellular dialysis membrane into the perfusion stream u nder controlled conditions. Conditions for obtaining optimum dialysis effic iency such as flow-rate and polarity modifier in the perfusion stream, pH a nd added salt in the sample solution, as well as chromatographic conditions were investigated. The results indicate that the dialysis achieved at a sa mple matrix pH value of 9.5 with 0.1 M NaCl addition, and the perfusate at 10-mul/min flow-rate offered optimum dialysis efficiency. The aniline and 2 -chloroaniline were well separated in an acceptable time on a reversed-phas e C, column eluted with 40% aqueous methanol solution at pH 7.0 and 1.0 ml/ min flow-rate. The proposed method provided a very simple procedure to dete rmine aniline and 2-chloroaniline in wastewater. Application was illustrate d by the analysis of aniline and 2-chloroaniline in wastewater released fro m a polymer factory. (C) 2001 Elsevier Science B.V. All rights reserved.