工业Ni/Al2O3催化剂在高温反应时（甲烷化、甲烷干气重整等）常存在Ni颗粒烧结和再生困难等问题。本项目基于NiAl2O4尖晶石的高温合成及其中的Ni可还原的化学原理，系统研究NiO纳米颗粒进入Al2O3通过固相反应生成表层NiAl2O4,和Ni纳米颗粒从NiAl2O4表面还原溢出分散的过程机理，通过调控NiO和Ni的扩散、反应、迁移、聚并等过程，以及NiAl2O4相界面的演变和Ni-载体之间的相互作用，探索NiO-Ni尖晶石-Ni颗粒-催化性能的构效关系和Ni活性颗粒的还原溢出分散机制，探讨失活Ni催化剂的直接再生方法，研究含Ni-Al多元尖晶石在Al2O3表面的形成过程和不同金属组分还原过程的个性特征、共性规律及协同效应，开发含高稳定性和活性的Ni新型复合催化剂，对于探明尖晶石型催化剂的科学理论和解决工业Ni催化剂存在的问题具有重要意义。

Ni/Al2O3 catalysts have been widely used in chemical industry. However, there are still some critical issues to be addressed, such as the sintering of Ni nanoparticles, carbon deposition, and the difficulty in regeneration of deactivated catalysts. Based on the chemistry principles of solid reaction between NiO and Al2O3 to produce highly stable spinel NiAl2O4, and reduction reaction of Ni species in NiAl2O4 at the high temperatures, this project will focus on the systematic investigation of the solid reaction and reduction reaction processes, in which, how NiO nanoparticles immerge into the Al2O3 to create surface NiAl2O4 and how Ni nanoparticles emerge from NiAl2O4 surface respectively. These will include the diffusion, reaction, immigration, and aggregation of NiO and Ni nanoparticles during the different processes, the change of interfacial NiAl2O4 spinel phase, and the interaction of Ni-supports. The structure-performance of NiO nanoparticles, Ni spinel, Ni nanoparticle, and their catalytic properties in both methanation (CO and CO2) and methane reforming with CO2 will be discussed to find the novel control strategy of re-dispersion of active Ni nanoparticles during reduction. In addition, the direct regeneration of deactivated Ni catalysts will be explored. Furthermore, the formation of Ni-Al multiple spinels on Al2O3 surface and the reduction of multiple metal species will be studied to understand their individual characteristics and general rules, as well as the synergistic effects, which will be helpful for developing new Ni composite catalysts. The successful implementation of this project will be significant not only in understanding the fundamental science of spinel-based catalysts but also in addressing some key issues occurred in industrial Ni catalysts.