Ti(Ⅳ)催化H_2O_2/O_3降解乙酸  

Degradation of acetic acid by Ti(Ⅳ)-catalyzed H_2O_2/O_3

作　　者：李文文[1] 刘朋朋[1] 张华[1] 石锐[1] 童少平[1] 马淳安[1] 

机构地区：[1]浙江工业大学化学工程与材料学院,绿色化学合成技术国家重点实验室培育基地,浙江杭州310032

出　　处：《化工学报》2010年第7期1790-1795,共6页CIESC Journal

基　　金：国家自然科学基金项目(50578146; 20876151);浙江省自然科学基金项目(Y5080178)~~

摘　　要：研究了酸性条件下Ti(Ⅳ)对H2O2/O3体系[Ti(Ⅳ)/H2O2/O3]降解水中乙酸效率的影响,优化了工艺参数,并对其机理进行了分析。结果表明:在pH为2.8条件下,加入Ti(Ⅳ)能明显提高H2O2/O3降解乙酸的效率,如30min后Ti(Ⅳ)/H2O2/O3对乙酸的去除率达到了52.0%,而H2O2/O3的去除率为5.6%。在本实验条件下,当钛离子浓度为6mg·L-1,过氧化氢投加量为120mg·L-1时,Ti(Ⅳ)/H2O2/O3体系对乙酸具有较高的降解率。pH对Ti(Ⅳ)/H2O2/O3降解效率的影响并不明显,这可能与体系在不同pH条件下均存在特定的引发剂有关。鉴于H2O2/O3的缺陷和特点,Ti(Ⅳ)/H2O2/O3更适合在酸性条件下使用,是H2O2/O3体系的有益补充。叔丁醇实验结果表明:Ti(Ⅳ)/H2O2/O3体系降解乙酸遵循羟基自由基机理。定量化计算表明,H2O2/O3和Ti(Ⅳ)/H2O2/O3的Rct值分别为5.548×10-9和2.128×10-7,表明后者能产生更多的羟基自由基。The effect of Ti（Ⅳ）on the efficiency of acetic acid degradation by H2O2/O3 was investigated under acid condition.The processing parameters were optimized,and the degradation mechanism was also analyzed. The results indicated that addition of Ti（Ⅳ）could promote greatly the oxidation of acetic acid by H2O2/O3 at pH 2.8,the efficiency of its decomposition reached 52.0% in 30 min for Ti（Ⅳ）/H2O2/O3 and only 5.6% for alone H2O2/O3.When Ti（Ⅳ）and H2O2 concentrations were 6 mg·L-1 and 120 mg·L-1,Ti（Ⅳ）/H2O2/O3 had the highest degradation efficiency of acetic acid.The effect of pH was not significant,which might be related to the specific initiating mechanism for various pH values.In view of the shortcomings and characteristics of H2O2/O3,Ti（Ⅳ）/H2O2/O3 system that can be a complement to H2O2/O3 process,is suitable for application in acid solution.The test by using tert-butyl alcohol showed that acetic acid degradation in Ti（Ⅳ）/H2O2/O3 system followed a hydroxyl radical-type mechanism.The Rct values of H2O2/O3 and Ti（Ⅳ）/H2O2/O3 calculated by relative method were 5.548×10-9 and 2.128×10-7,respectively,indicating that Ti（Ⅳ）/H2O2/O3 system could generate more hydroxyl radicals.

关 键 词：臭氧 Ti(Ⅳ) H2O2 乙酸 降解 

分 类 号：X703[环境科学与工程—环境工程]