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.%采用超临界甲醇处理活性炭,水浸渍制备负载钌炭催化剂,用N2物理吸附、Boehm滴定、X光电子能谱(XPS)和程序升温还原(TPR)等测试技术研究了超临界甲醇处理对活性炭表面结构及表面基团相对含量的影响,并以葡萄糖加氢生产山梨醇为模型反应对钌基催化剂的性能进行了评价.研究结果表明,超临界甲醇处理活性炭,活性炭的孔结构性能变化不大,但可有效降低活性炭表面含氧酸性基团的含量,使催化剂的还原温度升高,增强了载体和活性组分间的相互作用,有效的提高了钌的分散度,从而提高所负载催化剂的催化活性.在实验范围内,当超临界甲醇的温度为300℃,处理时间为12 h时,在4.0 MPa、120℃、葡萄糖的质量分数为50％的反应条件下,催化剂的反应速率(按Ru单位质量计)达到了118.65 mmol/(min·g),是未处理活性炭的1.96倍.
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