摘要
采用并流沉淀法分别制备了CuO-CeO_2(物质的量比为5∶1)、CuO-ZnO(物质的量比为5∶4)、CuO-ZnO-CeO_2(物质的量比为5∶4∶1)三组目标催化剂,通过X射线衍射(XRD)、氢气升温还原(H2-TPR)、CO_2程序升温脱附(CO_2-TPD)、氮气吸附-脱附、X射线光电子能谱(XPS)、N2O滴定表征技术对催化剂的物化性能进行了测试,并在高温高压微催化反应器中对催化剂进行活性评价。研究了CuO-ZnO-CeO_2组成对CO_2加氢合成甲醇的影响。结果表明,与二组分催化剂相比较,三组分CuO-ZnO-CeO_2催化剂物化性能及催化活性发生了很大变化,催化剂表面碱性位增强,热稳定性增强,CuO颗粒粒径变小,铜分散度以及氧空位浓度提高,最终催化活性显著提高。其中,CuO-ZnO-CeO_2催化剂中,CuO颗粒粒径为8.2 nm,铜的比表面积为68.4 m^2/g,铜分散度为7.19%,甲醇的选择性和收率分别为48.6%和0.057 mmol/(g·min),催化剂活性较好。
Three catalysts,CuO-CeO2( 5 ∶ 1 molar ratio),CuO-ZnO( 5 ∶ 4 molar ratio) and CuO-ZnO-CeO2( 5 ∶4 ∶1 molar ratio),were prepared by coprecipitation method.The physicochemical properties of the catalysts were characterized by X-ray diffraction( XRD),hydrogen temperature reduction( H2-TPR),CO2 temperature programmed desorption( CO2-TPD),nitrogen adsorption desorption,X-ray photoelectron spectroscopy( XPS),N2O titration. The activity of the catalyst was evaluated in a catalytic microreactor. The results showthat,the physicochemical properties and catalytic activity of the ternary CuO-ZnO-CeO2 catalyst are different from that of the binary catalyst,specifically,the strength of surface alkaline sites are increased,the thermal stability is enhanced,the particle size of CuO particles is reduced,the dispersion of copper and the concentration of oxygen vacancies are increased,and the catalytic activity is finally improved. In the CuO-ZnO-CeO2 catalyst,the CuO particle size is 8.2 nm,the specific surface area of copper is 68. 4 m^2/g,the copper dispersion is 7. 19%,the selectivity and the yield of methanol are 48.6% and 0.057 mmol/( g·min),respectively.
作者
霍海辉
高文桂
毛文硕
纳薇
闫晓峰
叶海船
HUO Hai-hui;GAO Wen-gui;MAO Wen-shuo;NA Wei;YAN Xiao-feng;YE Hai-chuan(State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming University of Science and Technology,Kunming 650093,China;Faculty of Metallurgy and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China;Faculty of Chemical Engineering,Kunming University of Science and Technology,Kunming 650093,China)
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2019年第5期523-531,共9页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金(51304099)
国家科技支撑计划课题(2011BAC01B03)资助~~
