SiO2-supported Pd nanoparticles for highly efficient, selective and stable phenol hydrogenation to cyclohexanone

• Published in: Molecular catalysis Vol. 538; p. 112975
• Main Authors: Xu, Junyuan, Zhu, Lihua, Zhang, Huan, Deng, Xin, Li, Kaihui, Chen, Bing Hui
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2023
• Subjects: Cyclohexanone; High dispersion; Phenol selective hydrogenation; SiO2; Cyclohexanone; Phenol selective hydrogenation; High dispersion; SiO2
• ISSN: 2468-8231; 2468-8231
• DOI: 10.1016/j.mcat.2023.112975

•The Pd/SiO2 catalysts with different Pd contents (Pd-0.16 wt%, 0.26 wt%, 0.52 wt%, 2.60 wt%) are prepared via sodium borohydride reduction.•Highly dispersed Pd nanoparticles are stably loaded on silica support with high specific surface area.•Pd/SiO2 (0.26 wt%) shows good catalytic performance for selective hydrogenation of phenol under mild reaction conditions (conversion-80.6%, selectivity to cyclohexanone-92.1%, TOF-1106.1 h−1).•Pd/SiO2 is also stable for phenol hydrogenation. Cyclohexanone is significant chemical reagent for organic synthesis, so it is key to design and prepare a highly active and environmentally friendly catalyst for the conversion of phenol to cyclohexanone. The results in this work show that the Pd-based supported nanocatalysts (Pd/SiO2) with various Pd contents (Pd/SiO2–1 with 0.16 wt% Pd, Pd/SiO2–2 with 0.26 wt% Pd, Pd/SiO2–3 with 0.52 wt% Pd, Pd/SiO2–4 with 2.60 wt% Pd) have high conversion and selectivity in phenol selective hydrogenation to cyclohexanone under relatively moderate reaction parameters, Pd/SiO2–2 with the highest conversion of 80.6%, selectivity of 92.1% and turnover frequency (TOF) of 1106.1 h−1. This excellent activity is attributed to the highly dispersed Pd nanoparticles (NPs) on silica with high surface area. The Pd/SiO2 catalysts are with high Pd dispersion and strong interaction of Pd-SiO2, which have been proved by XRD, XPS, BET, TEM, HRTEM, STEM, STEM-EDS elemental analysis techniques. The as-prepared materials have good catalytic behaviors in the selective hydrogenation of phenol and good stability, facilitating phenol hydrogenation to cyclohexanone and preventing the excessive hydrogenation of cyclohexanone to cyclohexanol. [Display omitted]