La-Ni/Al2O3-ZrO2催化剂中钙钛矿型LaNiO3的形成及其CO甲烷化性能  

Formation of perovskite-type LaNiO3 on La-Ni/Al2O3-ZrO2 catalysts and their performance for CO methanation

作　　者：王宏伟[1] 吴俊霞 王晓燕[1] 王红 刘进荣[1] WANG Hong-wei;WU Jun-xia;WANG Xiao-yan;WANG Hong;LIU Jin-rong(College of Chemical Engineering,Inner Mongolia University of Technology,Hohhot 010051,China)

机构地区：[1]内蒙古工业大学化工学院,内蒙古呼和浩特010051

出　　处：《燃料化学学报》2021年第2期186-197,共12页Journal of Fuel Chemistry and Technology

基　　金：the National Natural Science Foundation of China(21962014);Natural Science Foundation of Inner Mongolia(2016MS0219).

摘　　要：尽管Ni基催化剂已被工业化应用于CO甲烷化反应,但催化剂的积炭和烧结仍是需要解决的主要问题。本研究采用中和水解+柠檬酸络合法制备了负载型LaNiO3/Al2O3-ZrO2 CO甲烷化催化剂,研究了La-Ni负载量和载体焙烧温度对催化剂结构和催化活性的影响,用XRD、H2-TPR、BET、XPS、TEM等表征手段研究了催化剂前驱体到还原后的结构演变。结果表明,以均相的Al-Zr固溶体为载体制备的催化剂更易于形成LaNiO3结构的活性组分,LaNiO3还原的Ni0是保持高温活性的主要原因。La-Ni的负载量影响LaNiO3的存在和Ni还原状态。其中30%的La-Ni负载量易于形成LaNiO3,该催化剂还原后产生的Ni0和La2O3高度分散在载体表面,并且Ni0纳米粒子被载体和La2O3锚定,抑制了Ni0粒子在高温条件下的迁移和聚集而表现出高的热稳定性。The carbon deposition and sintering of Ni-based catalysts,used in CO methanation,are the main problems to be solved.In this paper,supported LaNiO3/Al2O3-ZrO2 catalyst was prepared by neutralization hydrolysis-citric acid complexation method.The effects of La-Ni loading and calcination temperature of support on the structure and catalytic activity of the catalyst were investigated.The structural evolution of catalyst precursor before and after reduction was studied via XRD,H2-TPR,BET,XPS,TEM and other characterization methods.The results showed that the catalyst supported by homogeneous Al-Zr solid solution was beneficial to form the active component with LaNiO3 structure,and the Ni0 derived from LaNiO3 was the key factor for keeping the activity at high temperature.The La-Ni loading affected the formation of LaNiO3 and the reduction state of Ni.Among the catalysts studied,30%of the La-Ni loading was more favorable for the formation of perovskite LaNiO3.The Ni0 and La2O3 reduced from LaNiO3 were highly dispersed on the surface of the support,and the Ni0 nanoparticles were anchored by the support and La2O3,which inhibited the migration and aggregation of Ni0 particles at high temperature and thus led to high thermal stability.

关 键 词：CO甲烷化 铝锆复合氧化物 钙钛矿 镍 氧化镧 

分 类 号：O643[理学—物理化学]