Sn掺杂影响Pt/CeO_(2)催化CO_(2)氧化丙烷脱氢性能的研究  

Impacts of Sn Doping on Pt/CeO_(2) Catalysts for the Oxidative Dehydrogenation of Propane with Carbon Dioxide

作　　者：彭超 刘忠文[1] PENG Chao;LIU Zhongwen(Key Laboratory of Syngas Conversion of Shaanxi Province,School of Chemistry&Chemical Engineering,Shaanxi Normal University,Xi’an 710119,China)

机构地区：[1]陕西省合成气转化重点实验室,陕西师范大学化学化工学院,陕西西安710119

出　　处：《化学反应工程与工艺》2025年第1期216-229,共14页Chemical Reaction Engineering and Technology

基　　金：国家自然科学基金(22338010)。

摘　　要：采用水热法合成了Sn掺杂的CeO_(2)(xSn-CeO_(2)),再浸渍Pt,制备了一系列Pt/xSn-CeO_(2)催化剂,并考察了其催化丙烷氧化脱氢(CO_(2)-ODP)反应的性能。结果表明,Sn掺杂形成了Ce1-xSnxO_(2)固溶体,且随Sn含量增加,Pt/xSn-CeO_(2)催化剂表面氧缺陷浓度先增大后降低,而Pt电子密度则单调降低。反应结果表明,随催化剂中Sn掺杂量从0增加到5%(质量分数),初始丙烷转化率先增大后降低;而初始CO_(2)转化率和丙烯选择性则分别呈现单调降低和单调升高的变化规律。其中,Pt/1Sn-CeO_(2)催化CO_(2)-ODP的性能最佳,其初始丙烷转化率和丙烯选择性分别为48.3%和73.2%。关联分析Sn影响Pt/CeO_(2)催化CO_(2)-ODP的结构和活性结果表明,氧缺陷含量和Pt电子密度是影响Pt/xSn-CeO_(2)催化CO_(2)-ODP活性的关键因素。上述认识为进一步优化设计Pt基CO_(2)-ODP高性能催化剂提供了重要的参考价值。A series of Pt/xSn-CeO_(2) catalysts was prepared by impregnating Pt into the hydrothermally synthesized xSn-CeO_(2),and was evaluated as a catalyst for the oxidative dehydrogenation of propane with carbon dioxide(CO_(2)-ODP).Experimental results revealed that the Ce1-xSnxO_(2) solid solution was formed over Pt/xSn-CeO_(2) catalysts irrespective of the Sn loadings.Moreover,the Pt electron density monotonically decreased while the oxygen-defect content firstly increased then decreased with increasing the Sn loadings in Pt/xSn-CeO_(2).The catalytic performance of Pt/xSn-CeO_(2) for CO_(2)-ODP strongly depended on Sn loadings.With increasing the Sn loading from 0 to 5%,the initial propane conversion firstly increased then decreased while the initial CO_(2) conversion and propylene selectivity monotonically decreased and increased,respectively.Thus,the Pt/1Sn-CeO_(2) showed the best catalytic performance for CO_(2)-ODP with an initial propane conversion of 48.3%and propylene selectivity of 73.2%.The correlation of the catalyst characterizations and catalytic results concluded that the Pt electron density and oxygen-defect content over the surface of Pt/xSn-CeO_(2) catalysts,which were regulated by the amount of the Sn doping,were key factors in determining the activity of CO_(2)-ODP.These understandings on the dual functions of the Sn doping and impacts on the catalytic performance were important for the further design and optimization of a high-performance Pt-based CO_(2)-ODP catalysts.

关 键 词：二氧化碳 丙烷 氧化脱氢 Pt基催化剂 Sn掺杂CeO_(2) 

分 类 号：O643.38[理学—物理化学]