Photocatalytic decomposition of difenoconazole from wastewaters

Abstract

Due to the rapid development of industry and growth of population, water consumption is increased. Beside this, releasing of xenobiotics, which represent significant pollutants into watercourse, like heavy metal ions, pesticides, paints, and solvents, made this problem much bigger. Therefore, they can enter into aquatic organisms directly from industrial plants or into human bodies indirectly through agricultural products. New technologies, including photocatalytic decomposition, are necessary for wastewater treatment as a highly efficient and low-cost process. Photocatalysis implies the degradation of various types of harmful organic substances to simple molecules such as CO2, SO2, ions, and water. The applied process has no detrimental effect on the environment and does not require additional chemicals for precipitation of the products. In this work, photodegradation of the pesticide difenoconazole (DFC) using a TiO2-based photocatalyst was examined using doubled wall thermoregulated quartz reactor. As a replacement for UVC radiation, solar imitated Ultra Vitalux (UV) lamp (300W) was used. Determination of DFC concentration was performed using a UV method. Degradation kinetics follows pseudo-first order. After 120 minutes, the DFC was completely degraded. Chemical oxygen demand (COD) also confirmed that successfully indicating that this process can be used in treating of industrial wastewater.