高选择性苯乙酮加氢Ni-Sn-B/SiO2非晶态催化剂的制备及表征

采用化学还原法制备了一系列三元非晶态Ni-Sn-B／SiO2催化剂,并考察了Sn含量对催化剂的苯乙酮选择加氢制备苯乙醇反应的活性及选择性的影响,同时对Sn改性前后的催化剂进行了系统的表征．XRD结果表明,Sn物种在催化剂表面高度分散,没有改变催化剂的非晶态结构．SEM结果也表明Sn的修饰并不改变非晶态合金的特征形貌．在苯乙酮加氢反应中,当Sn／SiO2=10wt％时,羰基加氢产物苯乙醇的得率可高达97．5％,且苯环加氢产物仅为0．5％,显示了良好的羰基加氢选择性．结合XPS结果,我们将该催化剂优异的催化性能归因于非晶态合金独特的电子结构、活性组分的高度分散及催化剂中Sn氧化物对羰基的选择性活化．

Highly Selective Amorphous Ni-Sn-B/SiO2 Catalysts in Acetophenone Hydrogenation to 1-Phenyl Ethanol

A series of amorphous Ni-Sn-B/SiO 2 catalysts with different tin contents were prepared by salt impregnation and KBH 4 reduction. The as-prepared catalysts exhibited excellent activity and selectivity in liquid phase hydrogenation of acetophenone (AP) to 1-phenyl ethanol (PE). A PE yield as high as 97.5% was achieved over the 10% Sn-NiB/SiO 2 catalyst, which is much higher than that over the amorphous Ni-B/SiO 2 or industrial Raney Ni catalyst. According to the characterizations including ICP, nitrogen physisorption, XRD, SEM, DSC and XPS, the superior catalytic behavior of the amorphous Ni-Sn-B/SiO 2 catalysts is attributed to the unique electronic structure of the amorphous alloy, the enhanced dispersion of the active components, as well as the activation of the carbonyl group by surface tin oxide.