Cobalt Element Effect of Ternary Mesoporous Cerium Lanthanum Solid Solution for the Catalytic Conversion of Methanol and CO2 into Dimethyl Carbonate

Molecules

Hua Shi¹  Xu Li²  Yunhan Gu²  Yanji Wang²  Qingyan Cheng² 

[1] China Tianchen Engineering Corporation, Tianjin 300499, China;Key Laboratory of Green Chemical Technology and High Efficient Energy Saving of Hebei Province, Tianjin Key Laboratory of Chemical Process Safety, School of Chemical Engineering, Hebei University of Technology, Tianjin 300401, China;

关键词: solid solution;    catalyst;    cobalt;    dimethyl carbonate;    oxygen vacancy;   

DOI  :  10.3390/molecules27010270

来源: DOAJ

【 摘 要 】

A citric acid ligand assisted self-assembly method is used for the synthesis of ternary mesoporous cerium lanthanum solid solution doped with metal elements (Co, Zr, Mg). Their textural property was characterized by X-ray diffraction, transmission electron microscopy, N₂ adsorption-desorption, X-ray photoelectron spectroscopy and TPD techniques, and so on. The results of catalytic testing for synthesis of dimethyl carbonate (DMC) from CH₃OH and CO₂ indicated that the DMC yield reached 316 mmol/g on Ce-La-Co solid solution when the reaction temperature was 413 K and the reaction pressure was 8.0 MPa. It was found that Co had synergistic effect with La and Ce, doping of Co on the mesoporous Ce-La solid solution was helpful to increase the surface area of the catalyst, promote CO₂ adsorption and activation, and improve the redox performance of solid solution catalyst. The conversion of Co²⁺ to Co³⁺ resulted in the continuous redox cycle between Ce⁴⁺ and Ce³⁺, and the oxygen vacancy content of the catalyst was increased. Studies have shown that the catalytic performance of Ce-La-Co solid solution is positively correlated with oxygen vacancy content. On this basis, the reaction mechanism of DMC synthesis from CO₂ and CH₃OH on the catalyst was speculated.

【 授权许可】

Unknown