A comparative study on Pt/CeO2 and Pt/ZrO2 catalysts for crotonaldehyde hydrogenation
A comparative study on Pt/CeO2 and Pt/ZrO2 catalysts for crotonaldehyde hydrogenation
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DOI：
10.1016/j.molcata.2012.05.002
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发表时间：
2012-09
影响因子：
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通讯作者：
Lin Zhu;Jiqing Lu;Ping Chen;Xiao Hong;Guanqun Xie;Gengshen Hu;M. Luo
中科院分区：
文献类型：
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作者：
Lin Zhu;Jiqing Lu;Ping Chen;Xiao Hong;Guanqun Xie;Gengshen Hu;M. Luo
以巴豆醛为原料，在Pt/CeO 2和Pt/ZrO 2催化剂上进行气相加氢反应。结果表明，两种催化剂均失活，巴豆醛转化率分别从Pt/CeO 2催化剂的31%和20%下降到6%和7%。程序升温氧化法分析表明，失活催化剂表面生成了有机物，CO通过脱羰反应对Pt原子的化学吸附产生了中毒作用。对于Pt/ZrO 2催化剂，巴豆醇的选择性达到48%，并且在反应过程中保持稳定，而对于Pt/CeO 2催化剂，巴豆醇的选择性急剧下降，从51%降至33%。Pt/CeO 2催化剂选择性的降低是由于CO与CeO 2中还原态Ce 3+反应在催化剂表面形成碳存款所致。而Pt/ZrO 2催化剂表面无碳存款，反应过程中选择性稳定。
Vapor-phase hydrogenation of crotonaldehyde was carried out over Pt/CeO2and Pt/ZrO2catalysts. It was found that both catalysts suffered deactivation, with the conversion of crotonaldehyde decreasing from 31 to 6% over the Pt/CeO2catalyst and 20 to 7% over the Pt/ZrO2catalyst, which was due to the formation of organic compounds on the catalyst surface as revealed by temperature programmed oxidation technique on the spent catalysts, and the poisoning effect of CO chemisorptions on Pt atoms via decarbonylation reaction. For the Pt/ZrO2catalyst, selectivity to crotyl alcohol reached 48% and kept stable during the reaction, while for the Pt/CeO2catalyst, the selectivity to crotyl alcohol decreased dramatically from 51 to 33%. The decrease of selectivity for the Pt/CeO2catalyst was attributed to carbon deposit formed on the catalyst surface by the reaction between CO and reduced Ce3+ion in CeO2. However, for the Pt/ZrO2, no carbon deposit was formed on the catalyst surface, which could account for the stable selectivity during the reaction process.