不同的沉淀剂对铁酸铜催化剂水煤气变换活性和热稳定性的影响(英文)  

Effect of various precipitants on activity and thermal stability of CuFe_2O_4 water-gas shift catalysts

作　　者：林性贻[1] 张勇[1] 殷玲[1] 

机构地区：[1]福州大学化肥催化剂国家工程研究中心,福建福州350002

出　　处：《燃料化学学报》2014年第9期1087-1092,共6页Journal of Fuel Chemistry and Technology

基　　金：Supported by National Engineering Research Center of Chemical Fertilizer Catalysts,Fuzhou University

摘　　要：以氢氧化钾、碳酸钠和碳酸氢钠为沉淀剂,采用共沉淀法制备3种铁酸铜催化剂,并对其水煤气变换活性和热稳定性进行了评价。测试发现,以氢氧化钾为沉淀剂制得的催化剂表现出优异的水煤气变换活性。通过X射线粉末衍射仪(XRD)、N2物理吸附(N2-physisorption)、H2-程序升温还原(H2-TPR)、CO2-程序升温脱附(CO2-TPD)和循环伏安法(CV)等技术手段研究了不同的沉淀剂对催化剂的微观结构和表面性质的影响。结果发现,氢氧化钾能有效促进CuFe2O4的生成、抑制CuO和CuFe2O4晶格的长大、促使CuO在催化剂表面的较好分散、增强催化剂的还原能力、增加弱碱性位点的数量。它们显著改善了催化剂的催化活性和热稳定性。Three kinds of CuFe2 O4 catalyts s were synthesized by cop-recipitation method using potassium hydroxide （ A） , sodium carbonate （ B） and sodium bicarob nate（ C） as the precipitants.Their catalty ic activity and thre mal stability were evalau ted in water-g as shift reaction （ WGSR） .The micor structure and surface property fo as-prepared catalysts was investigated by X-ray diffraction （XRD）, N2-physisorpit on, H2-temperature programmed reduction （H2-TPR）, CO2-temperature programmed desorption （CO2-TPD） and cyclic voltammetry （ CV） .The results show that the catalyst prepared with potassium hydroxide as precipitant exhibits excellent WGSR activity. Potsa sium hydroxide plays an important role in promoting the generation of CuFe2 O4 , restraining growth of crystalline CuO and CuFe2 O4 , resulting in much better dispersion of CuO on the surface of catalyts s, enhancing the reducibility of catalsy ts, and increasing the amount of weak basic sites.These factors remarkably improve the activity and thermal stability of catla ysts.

关 键 词：水煤气变换反应 铁酸铜催化剂 还原性 弱碱性位 热稳定性 

分 类 号：O643[理学—物理化学]