Comparison between the efficiency of advanced oxidation process and coagulation for removal organophosphorus and carbamat pesticides

ABSTRACT

Water pollution by pesticides has adverse effects on the environment and human health, as well .In recent years, advanced oxidation processes, have been gone through to a very high degree for pesticides removal. Poly-Aluminum chloride [PAC] used for water treatment, can be effective on pesticides removal. The aim of this research was to study the use of UV/O3 and PAC in the removal of pesticides from drinking water. In this descriptive- analytical survey, specific concentrations of pesticides [1,5,10,15,20 ppm];namely Diazinon, Chlorpyrifos, Carbaril were prepared through addition to deionized water. Dichloromethane was used for samples extraction, samples extracted with Liquid-Liquid and Solid-phase extraction, finally entered bath reactor at pH [6,7,9] .The samples then exposed to UV/O3at contact time of [0.5,1,1.5 and 2 hours]. In the PAC pilot, the effects of various concentrations of pesticides, and PAC - ranging [12/24 and 36 ppm] were investigated for the efficacy of pesticides removal. All samples analyzed by GC/MS/MS and HPLC. It was found that in U V/O3 reactor, with the rise of pH, decrease in pesticides concentration, and rise of contact time, the efficiency of removal increased too. In the PAC pilot, increase in PAC concentration and decrease in pesticides concentration, both increased the efficiency. Besides, both of the methods showed high efficiencies in the removal of both pesticides,i-e. halogenated Organophosphorus [Chlorpyrifos], non- halogenated Organophosphorus [Diazinon] at the degree of over [%80]; In case of carbamate pesticides [e.g. Carbaril] efficiency was over [>%90]. One-Way Anova and Two -Way Anova were used to analyze the obtained data. According these results these two methods are suggested for the removal of pesticides from aqueous solutions