高比表面铀氧化物固体酸的制备及其催化乙醇脱水性能的研究  

Preparation of Uranium Oxide-based Solid Acids with High Specific Surface Area and its Catalytic Performance for Ethanol Dehydration

作　　者：马雅婷 刘璐 罗明悦 赵玉宝[1] MA Yating;LIU Lu;LUO Mingyue;ZHAO Yubao(School of Chemistry and Chemical Engineering,University of South China,Hengyang,Hunan 421001,China)

机构地区：[1]南华大学化学化工学院,湖南衡阳421001

出　　处：《南华大学学报(自然科学版)》2024年第6期63-69,共7页Journal of University of South China:Science and Technology

基　　金：国家自然科学基金资助项目(22272074)。

摘　　要：以未除去模板剂的介孔氧化硅为主体,经模板交换同时引入UO_(2)^(2+)及SO_(4)^(2-)物种等过程,制得比表面积高达180 m^(2)/g的铀氧化物固体酸。物性表征的分析结果表明,所得样品中的铀氧化物处于高分散状态,U为正六价;NH_(3)程序升温脱附研究结果显示,高分散态铀氧化物固体酸的总酸量高达6.02 mmol/g,为体相铀氧化物固体酸的23倍;反应温度为300℃、乙醇重时空速为2.5 h^(-1)时,高分散态铀氧化物固体酸的乙醇转化率和乙烯选择性均为100%。在体积分数为60%的乙醇、乙醇重时空速为2.5 h^(-1)以及300℃反应条件下,高分散态铀氧化物表现出良好的酸催化稳定性:连续反应11 h,乙醇转化率保持在100%,乙烯的选择性保持在98.8%以上。The uranium oxide solid acid with high specific surface area of up to 180 m^(2)/g is prepared by introducing UO_(2)^(2+)and SO_(4)^(2-)species into mesoporous silicon oxide,without removing the template.The analysis results indicate that the uranium oxide in the samples are highly dispersed and U is hexavalent.The results of temperature-programmed desorption of ammonia show that the total acid content of highly dispersed uranium oxide solid acid is as high as 6.02 mmol/g,which is 23 times that of bulk phase uranium oxide solid acid.When the reaction temperature is 300℃and the space velocity is 2.5 h^(-1),the ethanol conversion and the selectivity to ethylene of the highly dispersed uranium oxide solid acid are 100%.In ethanol with a volume fraction of 60%,WHSV of 2.5 h^(-1)and 300℃,the highly dispersed uranium oxide exhibits good catalytic stability:the conversion of ethanol hits 100%and the selectivity to ethylene remains above 98.8%after continuous reaction for 11 h.

关 键 词：三氧化铀 酸改性 乙醇脱水 乙烯 

分 类 号：O643.36[理学—物理化学]