光催化降解有机磷农药研究

Research on Photocatalytic Degradation of Organophosphorus Pesticide

通过控制调节TiO_2的用量,来探究光催化降解乐果适宜工艺的条件。通过室内试验发现,有机磷农药只有在光照和催化剂同时存在的条件下,才能被有效地降解为PO_4^(3-)。此外,对于TiO_2光催化降解乐果而言,催化剂的用量存在一个最佳值,即在TiO_2的用量为4.0 g/L时,农药的降解率最大。之后通过正交实验,得到农药降解的最佳条件,即反应物的起始浓度为0.05 mol/L,pH值11,光照强度为250 W时,乐果的降解率最大,其降解率为37.5%。

Through adjusting amount of TiO_2, suitable process conditions for the photocatalytic degradation of dimethoate were investigated. Through indoor test, it＇s found that organophosphorus pesticide can be only degraded into PO_4（3-） in the presence of light and the catalyst at the same time. In addition, for the TiO_2 photocatalytic degradation of dimethoate, the dosage of the catalyst has effect on the degradation result, suitable TiO_2 dosage is 4.0 g/L. Through orthogonal experiment, the best condition of pesticide degradation was obtained as follows： initial concentration of reactant 0.05 mol/L, pH 11, light intensity 250 W. Under above conditions, the degradation rate of dimethoate rate is the maximum, 37.5%.