纳米TiO_2协同Fenton试剂光催化降解甲基橙

STUDY ON THE PHOTOCATALYTIC DEGRADATION OF METHYL ORANGE BY NANOMERTER TiO_2 SYNERGIZED WITH FENTON

采用纳米TiO2协同Fenton试剂光催化降解甲基橙,研究了纳米TiO2与Fenton试剂的协同效应,考察了H2O2用量、甲基橙溶液的初始浓度及初始pH值对降解效率的影响,并对其降解动力学规律作了初步探讨。结果表明:纳米TiO2强化了Fenton试剂对甲基橙的降解效率,它们之间产生了较强烈的协同效应。在实验过程中,纳米TiO2协同Fenton试剂光催化降解初始浓度30mg/L、pH=3.0的甲基橙120min,其降解率达到99.4%,分别是同等实验条件下单独纳米TiO2降解率的2.63倍,单独Fenton试剂降解率的2.32倍,是两者算术和的1.2倍。在实验浓度范围内,甲基橙的降解反应符合准一级动力学过程;与Fenton反应相比,在0.2、0.4、0.6g/L纳米TiO2的协同作用下,甲基橙的降解表现反应常数分别提高了1.71、2.51和3.36倍,半衰期相应缩短。另外,H2O2用量、甲基橙溶液初始浓度及初始pH对降解率有一定影响。

The photecatalytic degradation of methyl orange using Fenton synergized by nanometer TiO2 was investigated. The influence of H2 O2 concentration, initial concentration and pH of methyl orang on degradation efficiency was investigated, and the degradation kinetics was discussed. The results showed that, the synergistic effect to the degradation of methyl orange by Fenton synergized with nanometer TiO2 was observed. The photecatalytic degradation efficieney of 99.4%, which was 2.63 times alone by TiO2,2.32 times alone by Fenton, 1.2 times of their geometrical accumulation at the some experimental conditions, was reached in the synergistic system within 120min. The photocatolytic degradation of methyl orange by synergistic system and Fenton was followed with the pseudo first order kinetics under 0.2g/L, 0.4g/L, 0.6g/L nanometer TiO2 ,the pseudo first order kinetics constant of synergistic system increased 1.71,2.51and 3.36 times, respectively, compared with that of Fenton alone. The half life was shortened. Otherwise, H2O2 concentration, initial concentration and pH of methyl orange influenced its degradation efficiency.