Investigation of photocatalytic degradation of diazinon using titanium dioxide (TiO2) nanoparticles doped with iron in the presence of ultraviolet rays from the aqueous solution

Abstract

Diazinon is one of organophosphate pesticides which it is classifi ed as a relatively dangerous substance (Class II by World Health Organization). The aim of this study was to determine the effi ciency of photocatalytic degradation of diazinon using titanium dioxide (TiO2) nanoparticles doped with iron in the presence of ultraviolet light in aqueous solution. This cross-sectional study was conducted at the laboratory scale in a 2 L reactor. The nanoparticles were synthesized by sol-gel method. The degradation of diazinon was evaluated in various amounts of pH, time, nanoparticles dosage, and the concentration of diazinon. The obtained results were analyzed using Excel2007 and SPSS V. 16 software and regression test. The results showed that the increasing pH, reducing the concentration of diazinon and increasing contact time can lead to increase the removal effi ciency. The optimum pH was obtained to be in neutral range and at the pH=7. In addition, the optimum amount for contact time, nanoparticle dosage and diazinon concentration was found to be 60 min, 100mg/L and 50mg/L, respectively. The maximum removal effi ciency was 98.58. Photocatalytic processes have high capacity in removing of diazinon and can effectively mineralized this compound. Furthermore, the TiO2 nanoparticles are not toxic and they can be used to remove the pollutants in various industries. Thus, doped nanoparticles due to the small amount of nano-materials, low energy consumption and high effi ciency can be used as a good alternative to the removal of diazinon.