Preparation of Ni-rice husk carbon catalysts for the hydrodeoxygenation of vanillin

Publication date: October 2018Source: New Carbon Materials, Volume 33, Issue 5Author(s): Zhi-hao CHEN, Wei CHAO, Yi FENG, Lu JIN, Yan-chao ZHU, Xiao-min YANG, Zi-chen WANGAbstractNi-rice husk carbon catalysts with Ni loadings from 2 to 8 wt% were prepared by impregnating rice husk activated carbon with Ni(NO3) 2·6H2O solutions, followed by carbothermal reduction at temperatures from 500 to 950 °C. The valance, particle size and dispersion of nickel nanoparticles on the carbon, the graphitization extent of the carbon, and the pore structure of the catalysts were investigated by XRD, TEM, Raman spectroscopy and nitrogen adsorption. The activity and selectivity of the catalysts for the hydrodeoxygenation of vanillin to 2-methoxy-4-methylphenol were evaluated. Results indicate that by increasing the carbothermal reduction temperature, the specific surface area and micropore volume decrease, mesopore volume and average pore size increase, nickel particle size increases and the (002) peak of carbon appears and becomes sharp above 900 °C. The selectivity of all catalysts investigated is 100%. The catalytic activity is closely related to the Ni content and its dispersion on the carbon. A high Ni loading of over 6 wt% and reduction at temperatures higher than 800 °C lead to aggregation of the nickel nanoparticles, which lowers the catalytic activity.Graphical abstractNi-rice husk carbon catalysts with Ni loadings from 2 wt% to 8 wt% were prepared by impregnating rice husk activate...

Source: New Carbon Materials - October 30, 2018 Category: Chemistry Source Type: research