不同硅源的Cu/SiO2催化糠醛加氢制2-甲基呋喃

以硅溶胶和气相二氧化硅为载体，采用氨蒸法制备了Cu/SiO₂-sol和Cu/SiO₂-aer两种催化剂，采用N₂吸附脱附、X射线衍射（XRD）、傅里叶红外光谱（FT-IR）、透射电子显微镜（TEM）、N₂O-H₂滴定、氢气程序升温还原（H₂-TPR）、氨程序升温脱附（NH₃-TPD）及X射线光电子能谱（XPS）对样品进行表征，在固定床反应器中考察两种催化剂对糠醛气相加氢制2-甲基呋喃的催化性能。结果表明，Cu/SiO₂-sol催化剂具有更好的催化活性，在150 h反应时间内，糠醛转化率为100%，2-MF选择性在91%以上。这主要归因于以硅溶胶为硅源可以生成更多页硅酸铜，还原后催化剂表面Cu的分散性更高、弱酸位更多，有利于提高糠醛的转化率与2-甲基呋喃的选择性。同时Cu/SiO₂-sol具有较大的孔容孔径，有利于降低反应过程中积炭，延长催化剂寿命。

Catalytic hydrogenation of furfural to produce 2-methylfuran over Cu/SiO2 catalysts prepared by different silicon sources

Both Cu/SiO₂-sol and Cu/SiO₂-aer catalysts were prepared by the ammonia evaporation method using silicon sol and aerosil as silicon sources, respectively. The catalysts were characterized by N₂ adsorption-desorption, XRD, FT-IR, TEM, N₂O-H₂ titration, H₂-TPR, NH₃-TPD and XPS. The catalytic performances of Cu/SiO₂ catalysts for hydrogenation of furfural to produce 2-methylfuran were investigated in a fixed bed reactor. Compared with Cu/SiO₂-aer catalyst, the Cu/SiO₂-sol catalyst exhibits a higher catalytic performance. The conversion of furfural is 100% and the selectivity of 2-methylfuran is above 91% during the reaction of 150 h. CuO/SiO₂-sol catalyst favors the formation of rich copper phyllosilicate phase, which could provide more weak acid sites and better Cu dispersion on the surface of Cu/SiO₂-sol catalyst. Besides, the larger pore size of Cu/SiO₂-sol contributes to reducing the carbon deposition, which is beneficial to long service life of the catalyst.