| 十三氟辛基修饰的疏水有机-无机杂化二氧化硅膜孔结构、氢气分离及水热稳定性 |
| Pore Structure, Hydrogen Separation and Hydrothermal Stability of Hydrophobic Organic-Inorganic Hybrid Silica Membranes Modified by Perfluorooctyl Groups |
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| 摘要: 采用1，2-双（三乙氧基硅基）乙烷（BTESE）和十三氟辛基三乙氧基硅烷（PFOTES）为前驱体，在酸性条件下通过溶胶-凝胶法制备了十三氟辛基修饰的有机-无机杂化SiO2膜材料。利用接触角测量、红外光谱、动态光散射和N2吸附等测试技术分别对膜材料的疏水性、溶胶粒径和孔结构进行表征，并深入研究有支撑膜材料的氢气渗透、分离性能以及长期水热稳定性。结果表明，十三氟辛基修饰后的膜材料由亲水性变成了疏水性，当nPFOTES/nBTESE=0.6时膜材料对水的接触角达到（110.4±0.4）°，膜材料还保持微孔结构，孔径分布在0.5~0.8nm。氢气在修饰后的膜材料中的输运遵循微孔扩散机理，在300℃时，氢气的渗透率达到8.5×10-7mol·m-2·s-1·Pa-1，H2/CO2，H2/CO和H2/SF6的理想分离系数分别为5.49，5.90和18.36，均高于相应的Knudsen扩散分离因子。在250℃且水蒸气物质的量分数为5%水热环境下陈化250h，氢气渗透率和H2/CO2的理想分离系数基本保持不变，膜材料具有良好的水热稳定性。 |
| 关键词: 十三氟辛基 有机-无机杂化SiO2膜 孔结构 氢气分离 水热稳定性 |
| 基金项目: 国家自然科学基金（No.21171014，50502002）；国家863计划课题（No.2009AA03Z213）；北京市教育委员会科技计划重点项目（No.KZ201410005006）资助项目。 |
| Abstract: Organic-inorganic hybrid silica membranes were prepared by sol-gel technique using1,2-bis(triethoxysilyl)ethane (BTESE) and 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES) as precursors under acidic condition. The hydrophobic property, sol particle size distribution and pore structure of the modified silica membranes were characterized by contact angle measurement, FT-IR, dynamic light scattering and N2 adsorption, respectively. The hydrogen permeation, separation and hydrothermal stability of the supported membranes were also investigated in detail. The results show that hydrophobic microporous membranes are obtained after modification by perfluorooctyl groups, with a water contact angle of (110.4±0.4)° and a pore size ranging from 0.5 to 0.8 nm at a PFOTES/BTESE molar ratio of 0.6. At 300 ℃, the transport of hydrogen in the modified supported hybrid silica membranes complies with a micropore diffusion mechanism, with a high hydrogen permeance of 8.5×10-7 mol·m-2·s-1·Pa-1, a H2/CO2, H2/CO and H2/SF6 permselectivity of 5.49, 5.90 and 18.36, respectively, higher than those of the corresponding Knudsen value. Under a humid condition with a temperature of 250 ℃ and a water vapor molar ratio of 5%, the hydrogen permeance and H2/CO2 permselectivity of the modified silica membranes remain almost constant, indicative of an excellent hydrothermal stability for the membranes. |
| Keywords: perfluorooctyl groups organic-inorganic hybrid silica membranes pore structure hydrogen separation hydrothermal stability |
| 投稿时间：2013-10-26 修订日期：2013-12-10 |
| 摘要点击次数: 2275 |
| 全文下载次数: 2006 |
| 刘相革,韦奇,丁元利,聂祚仁,李群艳.十三氟辛基修饰的疏水有机-无机杂化二氧化硅膜孔结构、氢气分离及水热稳定性[J].无机化学学报,2014,30(5):1111-1118. |
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