Study on the Effective Process Parameters for Degradation of Herbicide Bentazone in Contaminated Water by Nano Metal Oxides of Titanium)IV(and Iron)III(Based on Natural Zeolite

In this study, the photocatalyst of TiO2/Fe2O3 based on clinoptilolite natural zeolite was synthesized by co-precipitation method and its function in degradation of Bentazone, as one of the most widely used herbicides in agriculture, was evaluated. The effect of process parameters simultaneously including pollutant concentration (1-40 mg/l), pH (4-10) and hydrogen peroxide concentration (25-100 mg/l) on photocatalytic degradation efficiency of Bentazone was investigated using design of experiments in response surface methodology. Synthesized photocatalyst was characterized by XRD, XRF, FT-IR, FE-SEM and EDX analyses. The results of XRD, FT-IR, and EDX confirmed the presence of TiO2 and Fe2O3 nanoparticles on the surface of clinoptilolite. The FE-SEM results confirmed the deposition of TiO2/Fe2O3 on the surface of clinoptilolite zeolite and also the approximate particle size of TiO2/Fe2O3 was 52 nm. According to XRF results, the synthesized nanoparticles had Fe3ﴸ optimal molar ratio of 0.06. The results showed that Bentazone concentration, pH and hydrogen peroxide concentration were the most effective factors on photocatalytic degradation efficiency of Bentazone, respectively. According to the experimental data at optimal conditions (pH, pollutant concentration and hydrogen peroxide concentration are 10, 10 mg/l and 50 mg/l, respectively), degradation efficiency of Bentazone was obtained 97% and the degradation efficiency was 78% at maximum concentration of pollutant (40 mg/l). This study showed that the synthesized photocatalyst has acceptable efficiency for degradation of non-biodegradable pollutant and removal pesticides from contaminated water.