Abstract 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.

中文翻译：

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

摘要 用于CO甲烷化的镍基催化剂的积碳和烧结是需要解决的主要问题。本文采用中和水解-柠檬酸络合法制备负载型LaNiO3/Al2O3-ZrO2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。通过XRD、H2-TPR、BET、XPS、TEM等表征方法研究了催化剂前驱体还原前后的结构演变。结果表明，均相Al-Zr固溶体负载催化剂有利于形成具有LaNiO3结构的活性组分，而LaNiO3衍生的Ni0是保持高温活性的关键因素。La-Ni负载量影响LaNiO3的形成和Ni的还原状态。在所研究的催化剂中，30% 的 La-Ni 负载量更有利于钙钛矿型 LaNiO3 的形成。由LaNiO3还原而成的Ni0和La2O3高度分散在载体表面，Ni0纳米粒子被载体和La2O3锚定，抑制了Ni0粒子在高温下的迁移和聚集，从而具有较高的热稳定性。