Effect of hydration on the surface basicity and catalytic activity of Mg-rare earth mixed oxides for aldol condensation

作     者：Zheng Wang Pascal Fongarland Guanzhong Lu Wangcheng Zhan Nadine Essayem 

作者机构：Key Laboratory for Advanced Materials and REsearch Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Institut de REcherches sur la Catalyse et l'Environnement de Lyon(IRCELYON)CNRS-Universite Lyon 12 Avenue Albert Einstein69626 Villeurbanne CedexFrance 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2018年第36卷第4期

页      面：359-366页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术] 0708[理学-地球物理学] 0703[理学-化学] 

基　　金：Project supported by National Basic Research Program of China(2010CB732300) 111 Project(B08021) China Scholarship Council for the Joint-Training Scholarship Program with Institut de Recherches sur la Catalyse et l'Environnement de Lyon(IRCELYON)and Universite Claude Bernard Lyon 1(UCBL1) 

主　　题：Mg rare earth mixed oxide Hydration treatment Water tolerance Aldol condensation Solid base catalyst Rare earths 

摘      要：Magnesium and rare earth mixed oxides（Mg3 REOx（RE=La, Y. Ce）） were prepared and characterized by Xray diffraction（XRD）, N_2 adsorption-desorption, infrared spectra and microcalorimetry of CO_2. The results reveal that the Mg_3 CeO_x catalyst is present in the form of Mg-Ce-O solid solution,while the Mg3 LaOx and Mg_3 YO_x catalysts are probably rare earth oxides dispersed on MgO surface. As a result, among the calcined Mg_3 REO_x catalysts, the Mg_3 CeO_x catalyst presents the highest rate constant for acetone aldolization, which is well correlated to its more homogeneous distribution of basic sites. In contrary, the Mg_3 YO_x catalyst exhibit the lowest catalytic activity for acetone aldolization. Upon hydration pre-treatment, the basic properties on the surface of the Mg_3 REO_x catalysts were changed markedly. The Mg_3 YO_x catalyst after hydration treatment shows the highest amount of basic sites on catalyst surface, and then exhibits the highest activity among the hydrated Mg_3 REO_x catalysts. These results make it possible to fine-tune basic sites for acetone aldolization.