Fe3O4/ZrO2-H2O2非均相类Fenton体系对3,4-二氯三氟甲苯的降解

以浸渍法制备的新型纳米Fe3O4/ZrO2为催化剂,3,4-二氯三氟甲苯(3,4-DCBTE)为目标污染物,用Fe3O4/ZrO2-H2O2非均相类Fenton体系对目标污染物进行降解,考察催化剂的催化效果和温度、pH、H2O2投加量和掺杂比等因素对催化剂催化效果的影响。结果表明,以纳米Fe3O4/ZrO2作为催化剂的非均相类Fenton体系对3,4-二氯三氟甲苯的处理效果极佳;随着温度的升高,纳米Fe3O4/ZrO2的催化效果不断提高;当pH降低时,催化剂的催化效果有明显提升,原始pH(pH=5.7)时反应去除效果最佳,去除率可达88.6%;催化剂用量的增加同样可以提高3,4-二氯三氟甲苯的降解效率;催化剂中Fe3O4:ZrO2的物质的量比为1:2时效果较其他掺杂比的催化剂效果更好,去除率最终可以达到96.82%;当H2O2投加量增加时,3,4-二氯三氟甲苯的降解效率先提高后降低,投加量为0.3 mL时去除效果最好,几乎可以完全去除目标有机物。以Fe3O4/ZrO2-H2O2非均相类Fenton体系处理3,4-二氯三氟甲苯时,目标污染物的降解符合一级反应动力学。

Degradation of 3,4-dichlorobenzotrifluoride by Fe3O4/ZrO2-H2O2 heterogeneous Fenton-like system

3,4-dichlorobenzotrifluoride (3,4-DCBTE) was dehalogenated with oxidation treatment by means of heterogeneous Fenton-like system, using nanoscale Fe3O4/ZrO2 as catalyst. This innovative nanoscale catalyst was prepared by the impregnated method. To find the most optimum catalytic conditions of nanoscale Fe3O4/ZrO2, the influence factors were investigated. The results indicated that the treatment effect of 3,4-DCBTE was significantly improved by adding nanoscale Fe3O4/ZrO2, the removal efficiency can reach 94.59% and the removal efficiency only need 20 minutes to reach 80%. As the temperature increasing, the catalytic effect of nanoscale Fe3O4/ZrO2 catalyst was constantly improved obviously. As the pH reducing, the effect of nanoscale Fe3O4/ZrO2 catalyst was also improved, when pH was not adjusted (pH=5.7), the removal efficiency was the best which can reach 88.6%. Also, an increase with the amount of catalyst could enhance the degradation effect. If the molar ratio of Fe3O4:ZrO2 is 1:2, the catalytic effect was better than others doping ratio catalysts. With the increase of dosage of hydrogen peroxide (H2O2), the degradation efficiency of 3,4-DCBTE firstly increased and then decreased. The optimum removal efficiency was observed with the dosage of 0.3 mL. The results also suggested that the reaction process followed the first-order kinetics.