文献类型：期刊文献

英文题名：Mechanisms of Caromatic-C bonds cleavage in lignin over NbOx-supported Ru catalyst

作者：Dong, Lin[1];Xia, Jie[2,3];Guo, Yong[1];Liu, Xiaohui[1];Wang, Haifeng[2,3];Wang, Yanqin[1]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Res Inst Ind Catalysis, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Res Inst Ind Catalysis, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[3]East China Univ Sci & Technol, Sch Chem & Mol Engn, Ctr Computat Chem, Shanghai 200237, Peoples R China

年份：2021

卷号：394

起止页码：94

外文期刊名：JOURNAL OF CATALYSIS

收录：;EI(收录号：20210409828407);WOS:【SCI-EXPANDED(收录号:WOS:000623666100010)】；

基金：This work was supported financially by the NSFC of China (No. 21832002, 21808063, 21872050, 21873028, 91945302, 22002043), Shanghai ShuGuang project (17SG30) and the Science and Technology Commission of Shanghai Municipality (10dz2220500, 18ZR1408500).

语种：英文

外文关键词：Lignin; Hydrogenolysis; C-aromatic-C bonds; NbOx species; Catalytic mechanism

摘要：Efficient and selective cleavage of C-aromatic-C linkages in lignin to enhance the productivity of monocyclic aromatic hydrocarbons is an extremely challenging and attractive task. Previously, we reported a Ru/NbOPO4 catalyst that realized the catalytic cleavage of both interunit C-C and C-O bonds in one-pot lignin conversions [Chem, 2019, 5, 1521-1536]. However, the roles of NbOx species in the selective C-aromatic-C cleavage are not clear and need to be extensively studied. Herein, we focus on the exploration of the catalytic mechanisms of C-aromatic-C bond cleavage over NbOx-supported Ru catalyst, by comparing with those of Ru/TiO2, Ru/ZrO2, and Ru/Al2O3 catalysts. It shows that the Ru/Nb2O5 catalyst exhibits high activity and remarkable selectivity to monocyclic hydrocarbons. A combined diffuse reflectance infrared Fourier Transform spectra (DRIFTS) and density functional theory (DFT) calculation analysis unambiguously confirmed that (i) NbOx not only can strongly adsorb phenylcyclohexane via benzene ring, but also selectively activate C-aromatic-C bond between benzene ring and cyclohexane; (ii) NbOx can promote the protonation of phenylcyclohexane with the assistance of H3PO4; and (iii) NbOx can significantly reduce the barrier of C-aromatic-C bonds cleavage of the carbocation intermediate (C6H5(H)C6H11+). A detail underlying mechanism has been established, which would have further implications to promote the design of new, high efficient catalysts. (C) 2021 Elsevier Inc. All rights reserved.