INFLUENCE OF THE ANODE MATERIAL ON THE PROCESS OF ELECTROCHEMICAL OXIDATION OF MALATHIONE

Abstract

Organophosphorus pesticides and expired pharmaceuticals, particularly malathion, are particularly common organic pollutants in water bodies. Malathion (malathion) is the active ingredient in insecticides and acaricides. For medical, sanitary, and household disinfestation, malathion-based products are used to kill lice and nits in adults and children.

Wastewater treatment for organophosphorus and biogenic phosphorus-containing compounds is a complex environmental challenge that can be addressed using various methods, but the effectiveness of individual methods does not provide the desired results. Among physicochemical methods for water treatment of organophosphorus pollutants, electrochemical methods have gained considerable interest in recent years.

This work continues our earlier research on the electrochemical oxidation of malathion using soluble anodes. This study investigates the electrochemical decomposition of malathion from aqueous solutions using insoluble anodes. In the main experiments, the temperature, current density, and malathion concentration were held constant to investigate the influence of the anode material and electrolyte background on the anodic oxidation of malathion. The optimal current density was 10 mA/cm², which was maintained throughout all experiments. Quantitative analysis of malathion was performed using an SF 2000 spectrophotometer.

Using SnO₂ and PbO₂ anodes in a chloride medium accelerates the electrochemical decomposition of malathion due to the release of chlorine gas and the formation of active chlorine. At a current density of 10 mA/cm² and a temperature of 20°C, an aqueous malathion solution with a concentration of 57 mg/L is completely oxidized. Furthermore, insoluble SnO₂ and PbO₂ anodes, as well as the chloride background electrolyte, are environmentally safe.