不同载体对催化臭氧氧化降解甲基橙的影响

INFLUENCE OF THE CATALYTIC OZONE OXIDATION ON DEGRADATION OF METHYL ORANGE BY DIFFERENT CARRIER MATERIAL

以偶氮染料甲基橙模拟废水为目标物,采用静态实验对比的方法,分析了活性炭、Al_2O_3和ZSM-5沸石3种载体材料与O_3之间的协同作用,考察了载体种类、pH、自由基抑制剂叔丁醇等因素对甲基橙去除率的影响。结果表明:与单独臭氧氧化和单独载体材料吸附相比,3种载体材料的加入均能明显提高臭氧氧化的效率,并且3种载体在臭氧氧化体系中的作用不同。在中性条件下,活性炭/O_3反应体系中活性炭吸附有机物起主要作用,同时在载体表面发生自由基反应,为Al_2O_3/O_3体系处理效果提高的主要原因;ZSM-5沸石对臭氧催化并不是表面自由基反应的作用,而是作为反应场所促进了臭氧和有机物的表面反应。

Choosing methyl orange（MO） as model compound,this paper studied the synergy between three carrier materials and ozone by using static experimental comparison method. The influences of carrier types,pH and a radical scavenger tertbutyl alcohol（TBA） on the degradation of MO during catalytic ozonation by three carrier materials were discussed. The results showed that carrier materials/O_3 process,compared with sole ozonation,significantly increased the removal efficiency of MO,and the effect of the three carrier materials in the ozone oxidation system was different. Under the neutral condition,activated carbon adsorbing organic matter in activated carbon/O_3 reaction system played a major role. It also catalysed a radical pathway on the surface of the carrier. The generation of hydroxyl radicals was the main reason of high catalytic activity with γ-Al_2O_3. On the hand,ZSM-5 zeolites were not based on radical chain reaction to catalytic ozonation,ZSM-5 zeolite promoted the surface reaction of ozone and the organic as places,instead providing free radicals.