An Improved Accurate Method for The Automated Determination of Residual Chlorine in Saline Water

摘要

The determination of residual chlorine with o-tolidine in saline water has been studied. The method proposed is based on the use of reverse flow injection analysis for the monitoring of chlorine in saline samples with low cost and reduction of waste production. The linearity of the method (up to 1.8 mg L-1) covers the chlorine concentrations used in most water treatment processes. The precision of the method was 0.93 % (RSD) for 1.4 mg L-1 chlorine. The method is also applicable to non-saline water and the limits of detection were 0.11 mg L-1 and 0.04 mg L-1 for saline and non-saline matrices, respectively. The method has been successfully applied to the analysis of residual chlorine in both synthetic and real samples. The sample throughput was 60 h-1.