Corrosion inhibition of chlorine dioxide with carboxylic acid water treatment agents

Microorganisms in circulating cooling water can be effectively controlled by injecting chlorine dioxide. The metal corrosion due to chlorine dioxide and the corrosion inhibition property of PBTCA (2-phosphonobutane-1,2,4- tricarboxylic acid), PESA (polyepoxysuccinic acid) and TH-628 (organic carboxylic acid complex reagent) in chlorine dioxide solution were investigated by rotary weight-loss measurement and electrochemical testing. The results indicated that the concentration of 0. 8 mg/L chlorine dioxide resulted in the lowest corrosive rate of carbon stell. Complex drugs TH-628, PBTCA and PESA had good inhibition effects. In the process of corrosion of carbon steel, complex reagent TH-628 has inhibition effect on the reactions of both anode and cathode. So t is a mixed inhibitor.