Simplified procedure for the determination of chemical oxygen demand using silver nitrate to suppress chloride interference

Abstract

A sealed-flask procedure for the determination of the chemical oxygen demand of wastewaters is described. Samples are digested at 150 °C in a glassstoppered flask using springs to retain the stopper. The use of sealed-flask conditions offers two advantages over reflux conditions: simplified apparatus and experimental procedure and improved suppression of chloride interference. The proposed procedure is similar to the standard procedure in accuracy and reproducibility of results.