The relationship of morphology and catalytic performance of CeO2 catalysts for reducing nitrobenzene to azoxybenzene under the base-free condition
The relationship of morphology and catalytic performance of CeO2 catalysts for reducing nitrobenzene to azoxybenzene under the base-free condition
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DOI：
10.1016/j.cclet.2020.05.023
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发表时间：
2020-06
影响因子：
9.1
通讯作者：
Xueke Zhou;Haitao Zhao;Shaojun Liu;Yang Yang-Yang;Ruiyang Qu;Chen Zhen;Xiang Gao
中科院分区：
文献类型：
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作者：
Xueke Zhou;Haitao Zhao;Shaojun Liu;Yang Yang-Yang;Ruiyang Qu;Chen Zhen;Xiang Gao
提出了在无碱条件下，氧化铈的形貌是硝基苯还原为偶氮氧苯的关键因素。为了提高偶氮氧苯的收率，研究了ceo2催化剂的构效关系。合成了7种不同形貌的ceo2催化剂，以获得不同的Ce3+比例和不同的比表面积。值得注意的是，随着Ce3+比例的增加，这些样品对硝基苯还原为偶氮氧苯的催化性能增强。该催化剂表面Ce3+比例最高，在150℃、1 MPa CO条件下，7 h对硝基苯的转化率为100%，偶氮苯的选择性为89.8%。初步机理分析表明，偶氮苯对副产物偶氮苯的存在导致偶氮苯具有较高的选择性。
CeO2morphology was proposed to be a crucial factor for reducing nitrobenzene to azoxybenzene under the base-free condition. Herein, the structure-activity relationship of CeO2catalysts was explored to improve the azoxybenzene yield. A series of CeO2catalysts were synthesized with seven morphologies to obtain different Ce3+proportion and various surface areas. Notably, the catalytic performance of these samples for reducing nitrobenzene to azoxybenzene enhanced with the increasing Ce3+proportion. With the highest surface Ce3+proportion, the Rod-CeO2catalyst exhibited 100% conversion of nitrobenzene and 89.8% azoxybenzene selectivity in 7 h at 150 °C under 1 MPa CO. Moreover, the preliminary mechanistic analysis indicated that the inhabitation of azoxybenzene to by-product azobenzene resulted in the high selectivity of azoxybenzene.