铬改性分子筛催化降解三氯乙烯研究  

Catalytic degradation of trichloroethylene over Cr/zeolite catalysts

作　　者：钱金泽[1] 李森[1] 罗勇[1] 陈明良[1] 

机构地区：[1]上海化工研究院,上海200062

出　　处：《环境科学学报》2016年第9期3419-3427,共9页Acta Scientiae Circumstantiae

基　　金：上海市浦江人才计划资助(2014;B类;No.14PJ1432600)~~

摘　　要：采用等体积浸渍法制备了Cr Ox改性系列分子筛催化剂.采用XRD、H2-TPR和NH3-TPD等对所制催化剂进行分析表征,结果表明分子筛表面有铬氧化物存在,且改性的催化剂具有氧化还原性和酸性.在固定床连续反应器-气相色谱在线检测装置上考察了所制备催化剂对三氯乙烯的催化燃烧降解活性,反应空速为15000 h^(-1),氧气浓度为10%.结果表明,Cr改性氢型丝光分子筛(H-MOR)活性最优,反应温度为309℃时2.5%Cr/H-MOR对三氯乙烯转化率达90%;稳定性实验结果表明2.5%Cr/H-MOR稳定性良好,反应400 min后催化活性有轻微下降,回收后的催化剂采用TG和XRD表征,发现其上无积碳且结构无变化.A series of zeolite supported chromium oxide catalysts were prepared by incipient wetness impregnation. The obtained catalysts were further characterized by using XRD,H2-TPR and NH3-TPD. The characterization results indicate that the chromium oxides were introduced on the surface of zeolite and the synthesized catalysts definitely possess proper acidic and redox property. The obtained catalysts were used in catalytic degradation of trichloroethylene（ TCE） in a continuous fixed bed reactor-online gas chromatography equipment with GHSV of 15000 h-1and oxygen concentration of10%. In the case of reaction temperature of 309 ℃,2. 5% Cr/H-MOR catalyst performed the best activity in catalytic degradation of TCE and the conversion of TCE was 90%. Moreover,the stability test results show that 2.5%Cr/H-MOR was durable,and the catalytic activity decreased slightly after400 min. The recycled catalyst was characterized by XRD and TG,and the results imply that no carbon deposition and structural change occurred.

关 键 词：三氯乙烯 催化燃烧 分子筛 铬氧化物 

分 类 号：X701[环境科学与工程—环境工程]