Effect of cyanuric acid on the rate of disinfection byproduct formation

CHED 829

David M. Robinson and Gordon H. Purser.
The formation of disinfection byproducts (DBPs) during water treatment is of great concern as chlorinated organics can pose health risks. We believe that the addition of part per million levels of cyanuric acid to drinking water at the time the residual chlorine is added may reduce the quantity of DBPs produced. The effect of cyanuric acid on the rate of production of DBPs in the water is examined using the rate of reaction between chlorine and a DBP intermediate, dichlorohydroxybenzoic acid. The rate of the reaction was followed by stopped-flow techniques as a function of reactant concentrations, pH and temperature. Evidence suggests that even small quantities of cyanuric acid added to treated water may significantly reduce the rate of DBP formation. This evidence is the subject of this presentation.