Abstract:

Activated carbon(AC) was modified by supercritical fluidic methanol in order to obtain materials with different surface properties. Several techniques were used to characterize the activated carbon and Ru/AC catalysts including N2 physisorption, Boehm titration, XPS and temperature-programmed reduction(TPR). The results show that supercritical fluid treatment does not remarkably change the surface structure of activated carbon, but significantly reduce the amount of the surface acidic groups. Thus Ru deposited on them will assemble. These led to a higher dispersion of Ru and enhanced the activity of the catalysts prepared by impregnation of AC supported with RuCl3 solution. The activities of Ru/AC catalysts for hydrogenation of glucose were tested under 4.0 MPa and 120 ℃. The results show that activities of Ru/AC catalysts prepared by supercritical fluid treatment are increased, and the highest reaction rate(in Ru mass unit) for hydrogenation of glucose reaches 118.65 mmol/(min·g), which was 1.96 times higher than that without treatment.

Key words: supercritical fluid, ruthenium catalyst, surface group, glucose hydrogenation, activated carbon