微波改性沸石/类芬顿技术的脱色效果

Decolorization Effect of Zeolite Modified by Microwave and Fenton-like Technology

采用微波法对天然沸石进行改性并负载铁,制备了改性沸石负载铁催化剂,在H2O2存在的条件下考察了微波改性沸石/类芬顿技术对水中孔雀石绿(MG)的脱色效果。结果表明,微波改性沸石的载铁量比未改性的和浸煮法改性的分别提高了37%和9%,对MG的脱色率分别提高了32%和13%;随着温度的升高,对MG的脱色效果增强;当过氧化氢浓度为40mmol/L时,对MG的脱色效果最好;羟基自由基是MG脱色反应的主要氧化活性物种;催化剂在高温(70℃)下使用时会有少量铁溶出,但再生后处理效果即可得到恢复。

The natural zeolite was modified by microwave, and Fe （ Ⅲ） was loaded to prepare a modified zeolite catalyst. The decolorization effect of malachite green （MG） by zeolite modified by micro- wave and Fenton-like technology in the presence of H202 was investigated. The results show that the Fe（ Ⅲ） loading on the zeolite modified by microwave rises by 37% and 9%, the decolorization rate of MG rises by 32% and 13% respectively in comparison with that of natural zeolite and that of natural zeo- lite modified by boiled Na2SO4 solution. The decolorization rate of MG is increased with the increase of temperature. The optimal decolorization rate of MG is achieved at the concentration of H2 02 40 mmol/L. The hydroxyl radical is the reactive intermediate in this system. Small parts of iron on the zeolite will dis- solve when the catalysts are used at high temperature （70 ℃ ）, but the catalytic ability can be recovered by the regeneration.