Degradation of pesticides in aqueous solution by goethite

ポスター発表梗概
Recently, the environmental pollution, especially marine ecosystem, by pesticides has become a serious problem. Due to their heavy use in agriculture and to their persistence, many of these compounds are present in surface and ground waters and have to be considered a potential risk for marine life as well as for drinking water quality. Various pesticides have been found as contaminants in surface and ground waters and microbial degradation is considered to be the primary mechanism for their dissipation from soil. In general, biological methods commonly require a long time for the wastewater containing pesticides at high concentration. Therefore, the rapid and simple wastewater treatment of pesticides is now required urgently. A variety of effective treatment techniques for aqueous pesticides have been proposed by ultrasonic irradiation, direct photolysis, UV irradiation in the presence of ozone or Fenton reagent and TiO2 as a photocatalyst. Iron oxide and hydrogen peroxide are common constituents of natural and atmospheric waters. Hence, we have investigated the degradation and mineralization of pesticides in water using the goethite/H2O2 system. The many factors, such as pH value and initial concentrations of goethite and H2O2, affected on the degradation were evaluated.