FeAlOx/MMT催化Fenton反应降解高浓度苯酚废水

以蒙脱土为载体制备负载型Fe/Al复合氧化物(FeAlOx/MMT)用于催化Fenton反应降解高浓度苯酚废水。实验结果表明,活性相FeAlOx中Fe/Al摩尔比为0.22时制备所得催化剂对Fenton反应具有最佳活性,且Fe/Al复合氧化物并未嵌入蒙脱土层间。在低温和高pH条件下催化体系存在诱导期,诱导期内FeAlOx/MMT缓释出Fe离子并进而由Fe离子催化溶液中的Fenton反应。通过对非均相催化降解苯酚废水的动力学研究发现,H2O2初始浓度、溶液的pH和反应温度对COD降解效率具有显著影响。调节降解过程中的温度序列和氧化剂引入程序能够缓解高温和高双氧水浓度双重因素耦合导致的HO.自消耗。在优化的降解条件下使用理论用量的H2O2可使得1 g/L的苯酚废水中苯酚降解率达到100%,而COD的降解率则达到97%。

Degradation of phenol of high concentration by FeAlOx/MMT catalyzed Fenton reaction

Fe/Al complex oxide supported on montmorillonite(FeAlOx/MMT) was applied in the heterogeneous catalyzed Fenton reaction for the degradation of phenol solutions of high concentration.The experimental results show that the prepared FeAlOx/MMT catalysts with the Fe/Al molar ratio of 0.22 are highly effective for the Fenton reaction and the Fe/Al complex oxide is confirmed to be supported outside the layer structure of montmorillonite.Under lower reaction temperatures and higher pH values,an induction period can be observed during which ferric ions are gradually released into the solution from the surface of FeAlOx/MMT catalysts.Consequently,the Fenton reaction in the solution is catalyzed by the released ferric ions.On the basis of reaction kinetics data,it is found that the initial concentration of H2O2,pH value of the solution and the reaction temperature have an overwhelming effect on the degradation efficiency of COD of phenol solutions.The unnecessary self-consuming of HO· due to the coupling between the high reaction temperature and high concentration of H2O2 can be partially controlled by applying temperature gradient and batch-wise addition of H2O2.Under the optimized reaction condition,phenol in the wastewater with the initial concentration of 1 g/L can be completely removed,with a high degradation rate of COD of 97% obtained.