Xiao Han, Dong Jiaming, Zhang Yimin, Cao Xiaohua, Li Yanhong, He Dedong, Luo Yongming, Wang Pingyan, Wang Hao
Faculty of Chemical Engineering, Kunming University of Science and Technology Kunming 650500 P. R. China
The Higher Educational Key Laboratory for Odorous Volatile Organic Compounds Pollutants Control of Yunnan Province, The Innovation Team for Volatile Organic Compounds Pollutants Control and Resource Utilization of Yunnan Province, Kunming University of Science and Technology Kunming 650500 P. R. China.
RSC Adv. 2024 Dec 10;14(52):39061-39068. doi: 10.1039/d4ra06740a. eCollection 2024 Dec 3.
The presence of abundant hydroxyl groups on the surface of AlO can promote the dispersion of Ni species but produce an inactive NiAlO phase at high temperatures. Moreover, the catalysts prepared by the conventional incipient wetness impregnation method lack the sites for the activation of CO, which leads to coke deposition and thus affects the catalyst activity. The above restricts the utilization of Ni in conventional Ni/AlO catalysts. In this paper, AlO support was pre-treated by acetic acid to selectively remove hydroxyl groups without affecting the coordination environment of Al. Results revealed that the AlO support after hydroxyl removal not only showed moderate metal-support interaction but also produced more sites for the adsorption and activation of the reactant, which significantly improves the utilization of nickel species and the stability of the catalyst. The conversion of CH and CO at 700 °C was as high as 88% and 90%, respectively, and has an excellent stability of 50 h. This study provides a feasible strategy for the design of highly active methane dry-reforming catalysts.
AlO表面大量羟基的存在可促进Ni物种的分散，但在高温下会生成无活性的NiAlO相。此外，通过传统等体积浸渍法制备的催化剂缺乏CO活化位点，这会导致积炭，进而影响催化剂活性。上述情况限制了传统Ni/AlO催化剂中Ni的利用率。本文采用乙酸对AlO载体进行预处理，以选择性去除羟基而不影响Al的配位环境。结果表明，去除羟基后的AlO载体不仅表现出适度的金属-载体相互作用，还产生了更多用于反应物吸附和活化的位点，这显著提高了镍物种的利用率和催化剂的稳定性。700℃下CH和CO的转化率分别高达88%和90%，并具有50 h的优异稳定性。该研究为高活性甲烷干重整催化剂的设计提供了一种可行策略。
