Efficient Ni/SiO2 catalyst derived from nickel phyllosilicate for xylose hydrogenation to xylitol

The lignocellulosic biomass utilization is a feasible way to obtain alternative fuels and chemicals. Xylitol as an ideal sweetener is one of the top twelve value-added chemicals derived from biomass. Xylitol is also used in the pharmaceutical and cosmetics industries. Thus, the production of xylitol from biomass is significantly important. A silica supported nickel catalyst derived from nickel phyllosilicate for efficient aqueous phase xylose hydrogenation to xylitol was developed in this study. Higher xylose conversion was observed over the nickel phyllosilicate derived catalyst compared to nickel oxide derived nickel catalyst prepared by impregnation and commercial Raney Ni catalyst. The excellent xylitol selectivity (approximately 99 %) was also obtained over the nickel phyllosilicate derived catalyst. The differences in structure and property resulted from different preparation methods were investigated by means of XRF, N2 physisorption, XRD, FT-IR, H2-TPR, TEM as well as H2TPD. The higher nickel dispersion of nickel phyllosilicate derived catalysts, which could be synthesized by ammonia evaporation and deposition-precipitation using Na2CO3 as precipitator, led to higher xylose conversion. In addition, the phyllosilicate derived nickel catalyst demonstrated outstanding stability. Consequently, phyllosilicate derived nickel catalyst is promising for the industrial application for the production of xylitol form xylose aqueous hydrogenation thanks to its higher activity and selectivity as well as good stability.