铝基类水滑石和复合氧化物负载Pt催化剂的制备及对甲基苯酚加氢脱氧反应的催化性能

采用共沉淀法制备了多种铝基类水滑石，焙烧后得到对应的复合氧化物；以水滑石或复合氧化物为载体，制备了系列Pt基催化剂，研究了该催化剂对甲基苯酚加氢脱氧反应的催化性能。结果表明，Pt基催化剂的性能与载体的组分组成和结构相关；当以不经焙烧的类水滑石做载体时，所制备的Pt基催化剂具有较高的活性。其中，Pt-Ni-Al-H催化剂的加氢脱氧活性最高，对甲基苯酚转化率达到99.8%，甲苯选择性为1.4%，而Pt-Zn-Al-H催化剂的直接脱氧活性最高，在275℃和氢压2MPa下反应1h后，甲苯选择性达到84.1%。研究发现，反应过程中所生成的甲基环己烷可进一步发生脱氢反应转化为甲苯，说明所制备的Pt基催化剂具有较好的脱氢活性，可节省脱氧过程中的氢气消耗量。

Preparation of Al-based layered double hydroxides and corresponding mixed oxides supported Pt catalysts and their performance in the hydrodeoxygenation of p-cresol

Al-based layered double hydroxides and corresponding mixed oxides were prepared and used as the supports for the Pt based catalysts; their catalytic performance in the hydrodeoxygenation (HDO) of p-cresol was then investigated. The results indicate that the catalytic performance of Pt based catalysts is related to the composition and structure of the support; Pt directly supported on the Al-based layered double hydroxides exhibits higher activity in p-cresol HDO than that supported on corresponding mixed oxides. Especially, for the HDO at 275 ℃ and 2 MPa for 1 h, the conversion of p-cresol over Pt-Ni-Al-H is 99.8%, with a selectivity of 1.4% to toluene, whereas the selectivity to toluene over Pt-Zn-Al-H reaches 84.1%. Moreover, the Pt based catalysts are also active for the dehydrogenation of methylcyclohexane to toluene, which can effectively reduce the hydrogen consumption in HDO.