Influence of the support composition and acidity on the catalytic properties of mesoporous SBA-15, Al-SBA-15, and Al2O3-supported Pt catalysts for cinnamaldehyde hydrogenation
Influence of the support composition and acidity on the catalytic properties of mesoporous SBA-15, Al-SBA-15, and Al2O3-supported Pt catalysts for cinnamaldehyde hydrogenation
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DOI：
10.1016/j.jcat.2011.06.017
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发表时间：
2011-08-15
影响因子：
7.3
通讯作者：
Murzin, Dmitry Yu.
中科院分区：
文献类型：
--
作者：
Handjani, Soraya;Marceau, Eric;Murzin, Dmitry Yu.
在化学成分不同的介孔载体上制备了三种具有相似金属颗粒尺寸（< 2 nm）的 Pt 催化剂，并在肉桂醛的液相加氢中进行了测试。 Pt/SBA-15 和 Pt/Al-SBA-15 有利于 C=C 键的氢化，后一种催化剂的反应速率明显更高。酸性载体改变了铂纳米粒子的吸附特性，改变了它们的表面电子密度以及可能的形态。相比之下，Pt/Al2O3 是该系列中对肉桂醇选择性最强的催化剂，C=C 和 C=O 氢化反应以相同的速率发生。假定靠近颗粒的路易斯酸性位点的存在有利于分子通过极性 C=O 键的吸附。即使肉桂醛氢化不需要酸性位点进行，载体的组成和酸度也会显着影响反应速率和选择性。 (C) 2011 Elsevier Inc. 保留所有权利。
Three Pt catalysts exhibiting similar metal particles size (< 2 nm) were prepared on mesoporous supports differing by their chemical composition and tested in the liquid phase hydrogenation of cinnamaldehyde. The hydrogenation of the C=C bond was favored with Pt/SBA-15 and Pt/Al-SBA-15, with significantly higher reaction rates on the latter catalyst. The acidic support changes the adsorptive properties of the platinum nanoparticles, modifying their surface electron density and possibly their morphology. In contrast, Pt/Al2O3 was the most selective catalyst of the series toward cinnamyl alcohol, with C=C and C=O hydrogenations taking place at the same rate. The presence of Lewis acidic sites close to the particles is assumed to favor the adsorption of molecules via their polar C=O bond. Even if cinnamaldehyde hydrogenation does not require acidic sites to be performed, the composition and acidity of the support significantly influence the reaction rate and selectivity. (C) 2011 Elsevier Inc. All rights reserved.