不同载体Ni基负载型催化剂对甲烷部分氧化制合成气催化行为研究  

Catalytic performance of nickel-based catalysts with different supports in partial oxidation of methane to synthesis gas

作　　者：王润平[1] 毛树红[1] 段秀琴[1] 李文斌[1] 王齐[1] 池永庆[1] 

机构地区：[1]太原科技大学化学与生物工程学院,山西太原030021

出　　处：《燃料化学学报》2015年第2期228-234,共7页Journal of Fuel Chemistry and Technology

基　　金：太原科技大学校青年基金(20123017)

摘　　要：采用浸渍法制备了单一载体(Al2O3、Zr O2、Ce O2)和Zr O2、Ce O2改性的Al2O3复合载体的Ni催化剂,考察了在甲烷部分氧化制备合成气反应中的催化性能。通过N2-物理吸附、H2程序升温还原、X射线衍射、NH3程序升温脱附和程序升温氧化等技术对催化剂进行了表征。结果表明,在单一载体催化剂中,Ni/Al2O3具有较大的比表面积,其初始反应活性较高,但该催化剂表面易形成大量的积炭而快速失活。Ni/Zr O2和Ni/Ce O2催化剂比表面积较小,活性金属Ni在其表面分散性差,催化剂具有较低的CH4转化率。而Ce O2和Zr O2改性的Al2O3复合载体催化剂,具有较大的比表面积,反应活性明显高于单一载体催化剂。Ce O2-Al2O3复合载体催化剂具有最高的反应活性和较好的反应稳定性。同时表明,含Ce O2催化剂反应后表面积炭较少,Ce O2的储放氧功能增强了催化剂对O2的活化,提高催化剂活性的同时,可以抑制积炭的生成。A series of Ni-based catalysts with different supports（ Al2O3,Zr O2,Ce O2,Ce O2-Al2O3 and Zr O2-Al2O3） were prepared by the methods of impregnation.The effects of supports on the physical structures and catalytic performance of the resultant catalysts in partial oxidation of methane（ POM） were investigated.The catalysts were characterized by N2 physical adsorption,X-ray diffraction,temperature programmed reduction by hydrogen,temperature programmed desorption of ammonia and temperature programmed oxidation.The results showed that the Ni/Al2O3 catalyst had a large BET specific surface area and high initial activity.However,the Ni/Al2O3 catalyst showed a serious deactivation due to the formation of large amount of carbon deposited on the surface of the catalyst.Ni/Zr O2 and Ni/Ce O2 catalysts displayed lowactivity,which resulted from its lowBET specific surface area and poor Ni O dispersion.The Ni/Zr O2-Al2O3 catalyst showed high activity and the Ni /Ce O2-Al2O3 catalyst exhibited the best activity and coking resistance among the catalysts.Ce O2 could effectively suppress carbon formation and the transformation to inactive carbon species,due to the oxygen storage and release ability.

关 键 词：甲烷 部分氧化 镍 载体 

分 类 号：O643[理学—物理化学]