摘要
采用一步水热合成法将WO3引入介孔分子筛SBA-15的骨架内,考察了不同反应温度、不同反应溶液酸度和不同TEOs预水解时间对其结构的影响,并利用N2吸附~脱附、xRD、紫外-可见固体漫反射等手段对其进行了表征。结果表明,反应温度和反应溶液酸度对样品比表面积的影响不明显,TEOS预水解时间过长或过短均不利于W进入到骨架结构当中,其最佳预水解时间为30min。同时,随着反应温度的升高,样品的晶胞参数、晶面间距、孔径、孔容逐渐增大;随着体系酸度的增加,样品的孔容、平均孔径逐渐减小,样品中非骨架W物种则增多。
A series of W-SBA-15 composite were synthesized via hydrothermal process. The influence of various reaction factors, such as solution acidity, reaction temperatures and TEOS pre-hydrolysis time, on the structure of WSBA-15 composite was investigated. The structure of the as-synthesized W-SBA-15 was characterized by XRD, DR UV-vis and nitrogen adsorption-desorption measurements. The results were as follows: (1) The W-SBA-15 samples retain the mesopore structure of SBA-15 synthesized under different conditions. (2) With the increase of reaction solution acidity, the specific surface area of the sample did not change obviously, but its pore size and pore volume decreased. Meanwhile, the ratio of non-skeleton tungsten oxides increased. (3) With the reaction temperature increasing, the specific surface area and wall thickness had little change, and the cell parameter, cell space, pore size and pore volume increased. (4) TEOS pre-hydrolysis time influenced the formation of skeleton tungsten and the optimal time is 30 min.
出处
《石油学报(石油加工)》
EI
CAS
CSCD
北大核心
2008年第B10期140-144,共5页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
河南省杰出人才创新基金(No.0221001200)和郑州大学创新性实验基金(2007CXSY045)资助
关键词
水热合成
W—SBA-15
结构表征
hydrothermal synthesis
W-SBA-15
structure characterization