镧掺杂TiO_2降解有机磷农药乐果的研究

Study on Degradation of Organophosphorus Pesticide Dimethoate by La-doped TiO_2

[目的]探讨改性后的TiO2对市售农药乐果的降解率。[方法]镧掺杂TiO2光催化降解乐果溶液,用钼酸铵分光光度法测定降解前后乐果溶液的浓度。[结果]镧掺杂显著提高了TiO2对乐果的降解率;当催化剂制备时,镧的最佳掺入量为0.15%,最佳煅烧温度为600℃;催化剂光催化降解乐果溶液时,在催化剂投入量为2 g/L、乐果溶液的起始浓度较低、光照时间为4 h时,乐果溶液的降解效率最好。[结论]镧掺杂后的TiO2能有效降解低浓度乐果溶液。

[Objective] To discuss the degradation of organophosphorous pesticide dimethoate by modified TiO2.[Method] Dimethoate solution was photocatalytic degraded by La-doped TiO2,and the concentration of the solution was detected by ammonium molybdate spectrophotometry before and after degradation.[Result] Doping of La enhanced TiO2＇s degradation of dimethoate;during the preparation of catalyst,the best doping amount of La was 0.15%,and the optimal calcination temperature was 600 ℃;during the photocatalytic degradation of dimethoate solution,the catalyst amount was 2 g/L,initial concentration of dimethoate solution was low,the degradation efficiency was the best when illumination time was 4 h.[Conclusion] La-doped TiO2 could effectively degrade low concentration of dimethoate solution.