Efficient hydrodeoxygenation of guaiacol to phenol over Ru/Ti–SiO2 catalysts: the significance of defect-rich TiOx species. Issue 15 (11th July 2022)

• Record Type: Journal Article
• Authors: Wang, Xinchao; Wang, Zhuangqing; Zhou, Leilei; Liu, Yanchun; Yang, Yinze; Zhang, Liyan; Shang, Zongling; Li, Hui; Xiao, Tingting; Zhang, Chao; Zhao, Fengyu
• Is Part Of: Green chemistry. Volume 24:Issue 15(2022)
• Page Start: 5822
• Page End: 5834
• Publication Date: 2022-07-11
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/d2gc01714h
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : Under relatively mild conditions (240 °C and 0.4 MPa H2 ), Ru/Ti–SiO2 exhibited higher activity for C–O bond cleavage compared with both Ru/SiO2 and Ru/TiO2 catalysts, and achieved high guaiacol conversion (83.6%) and phenol selectivity (70.4%). Abstract : Selective hydrodeoxygenation of lignin-derived phenolics to value-added aromatic products such as phenol with high efficiency and low energy consumption remains an important challenge in the field of biomass conversion. Herein, we fabricated a series of Ti-modified SiO2 supported catalysts (Ru/Ti–SiO2 ) with rich Ti 3+ defects and size-controllable Ru particles via a facile wet impregnation method for the conversion of guaiacol in an aqueous phase. Under relatively mild conditions (240 °C and 0.4 MPa H2 ), Ru/Ti–SiO2 exhibited higher activity for C–O bond cleavage compared with both Ru/SiO2 and Ru/TiO2 catalysts, and achieved high guaiacol conversion (83.6%) and phenol selectivity (70.4%). The catalytic activity was increased with the introduction of the Ti modifier, and the deoxygenation ability of the Ru/Ti–SiO2 catalyst gradually increased with the Ti content. The presence of Ti–O–Si linkages in the Ti-modified SiO2 support promoted the formation of defect-rich TiO x species, which further inhibited the aggregation of Ru particles and increased their dispersion, regardless of the high reduction temperature and high Ru loading. Besides, those small-sized TiO x interacted with Ru electronically and promoted the formation of Ru 0 species. The interface between Ru and TiO x species (Ru 0 –Ti 3+ ) of the Ru/Ti–SiO2 catalyst was confirmed as the main active sites for the deoxygenation of guaiacol, benefiting the activation of the C–O bond.