限域纳米空间制备高效HCl氧化CuO-CeO_2催化剂  

Synthesis of Efficient CuO-CeO_2 Catalysts in Limited Nanospace for HCl Oxidation

作　　者：邹冲[1,2] 戴勇[1,2] 费兆阳[1,2] 陈献[2] 汤吉海[2] 崔咪芬[2] 乔旭[1,2] 

机构地区：[1]南京工业大学材料化学工程国家重点实验室,江苏南京210009 [2]南京工业大学化学化工学院,江苏南京210009

出　　处：《分子催化》2015年第3期238-245,共8页Journal of Molecular Catalysis(China)

基　　金：科技支撑计划(2011BAE18B01);国家自然科学基金(21306089);江苏省高校自然科学基金(13KJB530006)

摘　　要：利用KIT-6的有序介孔作为限域空间制备了一系列的介孔Cu O-Ce O2催化剂.借助XRD、BET、Raman、ESEM、TEM和H2-TPR等手段对催化剂进行表征,并考察其在HCl氧化反应中的催化性能.结果表明:铜含量<35%时,Cu O物种高度分散在催化剂的表面或者进入Ce O2晶格,催化剂具有高比表面积(>140 m2·g-1)和较小的晶粒尺寸,其中25Cu O-Ce O2催化剂具备最高的表面氧空位浓度和最优的低温氧化还原性能,并在HCl氧化反应中表现出最佳的催化活性,O2/HCl=6,370℃时转化率达到90%.反应动力学结果表明,25Cu O-Ce O2中更多的高分散的Cu O促进了HCl在催化剂表面的吸附和活化,更高浓度的氧空位增强了氧分子的吸附和活化.A series of meosoporous CuO-CeO2 composite catalysts were prepared using the ordered pores of hard template KIT-6 as a limited nanospace.The prepared catalysts were characterized by XRD,BET,Raman,ESEM, TEMand H2-TPR.The performance of catalysts for gas-phase HCl catalytic oxidation to Cl2 were also investigated. The results showed that CuO species could highly disperse on the surface of CuO-CeO2 catalysts with Cu loading be-low 35%,as well as some Cu2+dissolved into the CeO2 lattice.In addition,the catalysts gained good surface area (>140 m2 ·g-1 )and small grain size.Among all catalysts,25CuO-CeO2 obtained the highest surface oxygen va-cancies concentrations,suitable CuO dispersion and best reducibility at low temperature,leading to a 90% conver-sion of HCl at 370 ℃ (O2 /HCl =6).Kinetic studies showed that the more highly dispersed CuO provided more ac-tive sites for HCl adsorption and activation,while the oxgen vacancies could obviously enhanced the adsorption and activation of gas-phase oxygen.

关 键 词：CuO-CeO2 硬模板 氯化氢 氯气 氧空位 

分 类 号：O643.36[理学—物理化学] TB383.1[理学—化学]