酸化及碱化膨润土负载镍催化CO_2甲烷化反应  

Catalytic Methanation of CO_2 over Ni Supported on Acidified and Alkalified Bentontie

作　　者：张荣斌[1] 徐校燕[1] 王亮[1] 姚刘晶[1] 古宁宇[1] 杨震宇[1] 居艳[1] 

机构地区：[1]南昌大学化学系,南昌330031

出　　处：《应用化学》2011年第2期203-208,共6页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(20763005);江西省教育厅基金(GJJ10291)资助项目

摘　　要：采用盐酸和氢氧化钾对膨润土(BEN)进行改性处理,通过浸渍法制备了改性后膨润土负载的镍催化剂,并对其在二氧化碳甲烷化过程中的催化性能进行了研究。借助BET、XRD、TPR和TPD等测试技术对催化剂进行了表征。结果表明,用碱处理后的膨润土比表面积小于酸处理膨润土的,但以碱处理的膨润土为载体所制备的镍催化剂(Ni/alkali-BEN)具有更高的催化活性和生成甲烷的选择性。CO2-TPD和TPR研究表明,碱处理膨润土后能使镍的还原温度降低,活性中心数量增加,CO2吸附量增大。TPR和XRD测试结果表明,催化剂中易还原的NiO是最主要的镍物种,并且在Ni/alkali-BEN上NiO更多,这可能是其活性高的重要原因。HCl and KOH were used to modify bentonite（BEN）.The Ni catalysts supported on acidified and alkalified bentonite had been prepared by aqueous impregnation.Methanation of carbon dioxide was used as a probe reaction to characterize the catalytic performance.The samples were characterized by BET,XRD,TPR and TPD.The results showed that a higher catalyst activity was achieved for Ni/alkali-BEN,although the alkali-BEN had lower surface area.CO2-TPD and H2-TPR study showed that Ni/alkali-BEN could absorb more carbon dioxide and be reduced easier.XRD and TPR analysis indicated that nickel oxide was the dominant species for both catalysts,which was easily reduced to metal nickel.The amount of nickel oxide presented in the Ni/alkali-BEN was higher than that of Ni/acid-BEN,which might account for the higher activity of Ni/alkali-BEN.

关 键 词：改性膨润土 二氧化碳加氢 甲烷化 

分 类 号：O643.3[理学—物理化学]