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Indexed by:期刊论文

Date of Publication:2017-11-29

Journal:INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

Included Journals:SCIE、EI

Volume:56

Issue:47

Page Number:14034-14042

ISSN No.:0888-5885

Abstract:Various TiO2, SiO2, Al2O3, and Nb2O5-Al2O3 supported Pt catalysts have been prepared by urea precipitation method for catalytic hydrodeoxygenation (HDO) of diphenyl ether (DPE) as a 4-O-5 aryl-ether lignin model compound. The selectivity toward deoxygenated product cyclohexane increased obviously with Nb2O5-nH(2)O decorated, owing to the significant promotion effect of NbOx species and acid sites on C-O bond cleavage. At higher pressure (3.0 MPa H-2), DPE underwent a HYD route, while direct hydrogenolysis route occurred at low pressure (0.1 MPa H-2). In addition, the reaction rate constants and activation energies were obtained in the temperature range from 160 to 220 degrees C. Based, on the Arrhenius law, the activation energy for the cleavage of the C-O bond in DPE was calculated to be 91.22 kJ/mol. It was noteworthy that the Pt/20Nb Al2O3 showed higher stability than Pt/Al2O3 for hydrodeoxygenation of diphenyl ether, which can be attributed to its water -tolerant Lewis acid sites.