MO_x-CeO_2/HZSM-5催化剂催化氧化含氯挥发性有机物研究  

Catalytic oxidation of chlorinated volatile organic compounds over MO_x-CeO_2/HZSM-5 catalysts

作　　者：薛晓敏[1] 黄琴琴[1] 周仁贤[1] 

机构地区：[1]浙江大学催化研究所,杭州310028

出　　处：《环境科学学报》2011年第11期2394-2402,共9页Acta Scientiae Circumstantiae

基　　金：国家重点基础研究计划(973)项目(No.2004CB719504)~~

摘　　要：采用浸渍法制备了不同过渡金属掺杂的MOx-CeO2/HZSM-5(M分别表示Cr、Mn、Fe、Co、Ni和Cu)催化剂,研究了各催化剂对1,2-二氯乙烷(DCE)的催化降解性能.结果表明,过渡金属掺杂后,MOx-12%CeO2/HZSM-5催化剂催化氧化1,2-二氯乙烷(DCE)的活性明显提高.各催化剂(记为M-CeO2/HZSM-5)对DCE的催化氧化活性顺序为:9%Ni-12%CeO2/HZSM-5>9%Co-12%CeO2/HZSM-5、9%Mn-12%CeO2/HZSM-5>9%Cu-12%CeO2/HZSM-5、9%Cr-12%CeO2/HZSM-5>9%Fe-12%CeO2/HZSM-5>12%CeO2/HZSM-5.掺杂Co、Mn和Cu的催化剂上产生了较多的C2HCl3和C2Cl4等多氯烃副产物,尤其9%Cu-12%CeO2/HZSM-5催化剂上还产生少量的C2H2Cl4,容易产生二次污染.9%Cr-12%CeO2/HZSM-5催化剂具有良好的DCE催化降解性能,由于CrOx与CeO2之间的强相互作用,提高了活性氧物种的流动性,从而促进了DCE的脱氯降解和深度氧化.The catalytic performance of MOx-CeO2/HZSM-5 （M= Cr,Mn,Fe,Co,Ni and Cu） catalysts prepared by an impregnation method were evaluated in the oxidation of 1,2-dichloroetane （DCE）.The introduction of secondary transition-metal-oxide component can greatly improve the catalytic activity of CeO2/HZSM-5 for DCE destruction.The catalytic activities of MOx-CeO2/HZSM-5 catalysts decrease as the order of 9%Ni-12%CeO2/HZSM-5 9%Co-12%CeO2/HZSM-5,9%Mn-12%CeO2/HZSM-5 9%Cu-12%CeO2/HZSM-5,9%Cr-12%CeO2/HZSM-5 9%Fe-12%CeO2/HZSM-5 12%CeO2/HZSM-5.Large amounts of polychlorohydrocarbon such as C2HCl3 and C2Cl4 were generated over Ni,Co,Mn and Cu impregnated catalysts.Moreover,small concentration of C2H2Cl4 was found when 9%Cu-12%CeO2/HZSM-5 was used as the catalyst.The generation of polychlorohydrocarbon can cause secondary pollution.Among all the catalysts,9%Cr-12%CeO2/HZSM-5 not only displayed high activity for DCE destruction,but also produced the least polychlorohydrocarbons and showed high selectivity to CO2 and HCl.The improved capability of dehydrochlorination and the deep oxidation of DCE were attributed to strong interactions between CrOx and CeO2,which prompted the migration of active oxygen species on 9%Cr-12%CeO2/HZSM-5 surface.

关 键 词：催化氧化 挥发性有机物(VOCs) 1 2-二氯乙烷 CEO2 过渡金属氧化物 HZSM-5分子筛 

分 类 号：X131[环境科学与工程—环境科学]