REMOVAL OF CARBAMATE INSECTICIDE FROM WASTEWATER USING UV/TIO2 AND UV/ZNO

Abstract

Pesticides are widely used in agriculture to ensure good yields and proper harvesting as well as minimal storage losses. Most pesticides are resistant to chemical and/or photochemical degradation under typical environmental conditions. The presence of pesticides residues in water and food-chains may have a harmful effect on human health and on the equilibrium of ecosystems. Carbamates is a group in which having a very huge family used as insecticides, herbicides and fungicides. These are commonly used as insecticides similar to organophosphates and contains carbofuran compound which is highly toxic in nature. Zinc oxide (ZnO), Titanium dioxide (TiO2) considered as a catalyst of choice for such surface reactions as it has good chemical stability, low cost, and high UV/solar photo activity. Photo catalytic degradation of this insecticide with help of semiconductors like TiO2 and ZnO in presence of UV or solar light is an environmentally friendly and ecological process. ZnO and TiO2 considered as a catalyst of choice for such surface reactions as it has good chemical stability, low cost, and high UV/solar photo activity. Photo catalytic degradation of carbamate insecticide by using TiO2 and ZnO in presence of UV light the parameter that impact on rate of reduction are contact time, concentration of insecticide, pH of solution and mass of catalyst. As Carbamate is colorless so we need to add some reagents before measurement of absorbance. NaOH, add the mixture of HCl and Sodium Nitrite, and finally add coupling agent Sulfonic acid or Nitro aniline. Finally add these all mixture of reagents in above distilled water solution of Carbamate. The maximum reduction of Carbamate is 90%, and 92 % for 10 ppm solution resp. at 120 min. using ZnO/UV and TiO2/UV process with 1.5 Gms/lit of ZnO and TiO2 catalyst amounts. Both the processes are economical and having same efficiency for Carbamate reduction.