Oxidation of ethylbenzene to acetophenone by a Mn catalyst supported on a modified nanosized SiO2/Al2O3 mixed-oxide in supercritical carbon dioxide
Oxidation of ethylbenzene to acetophenone by a Mn catalyst supported on a modified nanosized SiO2/Al2O3 mixed-oxide in supercritical carbon dioxide
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DOI：
10.1016/j.apcatb.2012.02.019
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发表时间：
2012-05-30
影响因子：
22.1
通讯作者：
Gil, A.
中科院分区：
文献类型：
--
作者：
Arshadi, M.;Ghiaci, M.;Gil, A.
在无有机溶剂的超临界二氧化碳中，以SiO_2/Al_2O_3负载的锰为催化剂，叔丁基氢过氧化氢选择性氧化乙苯为苯乙酮，转化率为91%，选择性为98%。催化剂可以重复使用至少8次，而不会有明显的活性损失。这一过程简化了反应产物的分离，并且在温和的条件下只使用二氧化碳作为溶剂。本文还研究了多壁碳纳米管表面负载的锰纳米催化剂的电化学性能。结果表明，以2-氨基乙基-3-氨丙基三甲氧基硅烷(2-AE-3-APTMS)为载体的改性SiO_2/Al_2O_3复合氧化物上的锰催化剂具有较好的氧化环境、较低的氧化电位和较低的电荷转移阻力，因而具有比3-氨基丙基三甲氧基硅烷(3-APTES)更高的催化活性和选择性。(C)2012爱思唯尔B.V.保留所有权利。
The selective oxidation of ethylbenzene to acetophenone with tert-butyl hydroperoxide in the presence of an SiO2/Al2O3-supported manganese catalyst occurs with a conversion of 91% and a selectivity of 98%, in the absence of an organic solvent, in supercritical carbon dioxide. The catalysts could be reused at least eight times without significant loss of activity. This procedure simplifies the isolation of the reaction products and has the advantage of using only carbon dioxide as a solvent under mild conditions. The electrochemical data for Mn nanocatalysts immobilized at the surface of multi-walled carbon nanotubes were also studied. The results indicate that the Mn catalysts anchored on the modified SiO2/Al2O3 mixed-oxide via 2-aminoethyl-3-aminopropyltrimethoxysilane (2-AE-3-APTMS) have an easily oxidizable environment, lower oxidation potential and lower charge-transfer resistance, thus leading to a higher catalytic activity and selectivity than when 3-aminopropyltrimethoxysilane (3-APTES) is used. (C) 2012 Elsevier B.V. All rights reserved.