紫外强化湿式催化过氧化氢氧化降解活性艳红X-3B的实验及机理分析  

Experiments and mechanism analysis on the degradation of Reactive Brilliant Red X-3B by UV-assisted CWPO

作　　者：涂盛辉[1] 朱细平[1] 刘婷[1] 梁海营[1] 杜军[1] 彭海龙[1] 

机构地区：[1]南昌大学环境与化学工程学院,南昌330031

出　　处：《环境化学》2014年第9期1531-1537,共7页Environmental Chemistry

基　　金：国家自然科学基金项目(51162022;21201098)资助

摘　　要：比较湿式催化过氧化氢氧化(CWPO)和光催化联合湿式催化过氧化氢氧化(UV-CWPO)对活性艳红X-3B的处理效果,结果发现后者具有较大的优势,反应150 min后,染料脱色率分别为84.10%和99.28%.动力学实验表明,两者均符合一级反应动力学方程,且相同反应温度下,UV-CWPO工艺表观动力学系数为CWPO工艺的1.64—2.75倍;两者表观活化能Ea分别为40.24 kJ·mol-1和32.79 kJ·mol-1,UV-CWPO工艺具有更低的反应活化能,意味着该工艺下染料分子更容易氧化为各种中间体,进而引起染料脱色.比较CWPO工艺和UV-CWPO工艺反应机理,发现两者在链的引发期不同,并通过叔丁醇作为羟基自由基捕获剂证实前者羟基自由基(·OH)产生量较后者更少.利用GC-MS检测分析CWPO工艺和UV-CWPO工艺降解活性艳红X-3B过程中产生的中间产物,结果表明两者产生了相同的中间产物,但是前者产生量明显更少,这说明UVCWPO工艺对活性艳红X-3B降解更充分.This article compared the treatment effect of Reactive Red X-3B by catalytic wet peroxide oxidation（ CWPO） and UV-assisted catalytic wet peroxide oxidation（ UV-CWPO）,and found that the latter had significant advantage. After 150 min reaction,the decolorization rates of the dye were84. 10% and 99. 28% respectively. The kinetic experiments showed that both processes fitted well to pseudo-first order kinetics model. The apparent kinetic rate of UV-CWPO process was 1. 64—2. 75 times faster than CWPO process at the same temperature,and the apparent activation energy Eawas40. 24 and 32. 79 kJ·mol-1respectively. UV-CWPO process had a lower activation energy,which meant that in the process the dye molecules were more easily oxidized to a variety of intermediates.Similarities and differences in the reaction mechanism between CWPO and UV-CWPO process were explored and compared. The result indicated that the difference of both processes lied in the initiation of chains,and the former produced less hydroxyl radical（ ·OH）,which was confirmed by tert-butanol. The degradation intermediates were detected by GC-MS. The results showed that CWPO and UV-CWPO process produced the same types of intermediates,but the former produced significantly less amount..

关 键 词：UV-CWPO CWPO 活性艳红 反应机理 羟基自由基 中间产物 

分 类 号：X788[环境科学与工程—环境工程]