Preparation and microstructural analysis of high-performance mordenite membranes in fluoride media
Preparation and microstructural analysis of high-performance mordenite membranes in fluoride media
复制标题
氟化物介质中高性能丝光沸石膜的制备及微观结构分析
DOI：
10.1016/j.micromeso.2012.02.023
复制
发表时间：
2012-07-01
影响因子：
5.2
通讯作者：
Kita, Hidetoshi
中科院分区：
文献类型：
--
作者：
Zhou, Rongfei;Hu, Zhongli;Kita, Hidetoshi
采用一次水热法在多孔管状莫来石载体上制备了高性能的丝光沸石膜。采用X射线衍射（XRD）、场发射扫描电子显微镜（FE-SEM）、能量色散X射线光谱（EDX）、魔角旋转核磁共振（MAS NMR）和水滴接触角等手段对丝光沸石膜和丝光沸石粉进行了表征。氟源和合成温度对膜的微观结构（亲水性和结晶形态）和渗透汽化性能有影响。F-19 MASNMR证据表明，氟阴离子作为阳离子的抗衡物存在于丝光沸石晶体的通道中。使用NH 4F改性的凝胶制备的八种丝光沸石膜（M-3系列）显示出1.50 +/- 0.25 kg m（-2）h（-1）的高通量以及对于水/乙醇（10/90 wt.%）的1380 +/- 110的高分离因子。混合物在75摄氏度。该膜对水/异丙醇混合物也显示出良好的水选择性。在氟化物介质中制备的丝光沸石膜的高性能归因于较薄的沸石层和良好的表面亲水性。(C)2012 Elsevier Inc. All rights reserved.
High-performance mordenite membranes were prepared in fluoride media on porous tubular mullite supports by a single hydrothermal synthesis. Mordenite membranes and powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), magic-angle spinning nuclear magnetic resonance (MAS NMR) and contact angle with water droplets. The microstructure (i.e. hydrophilicity and crystal morphology) and pervaporation (PV) performance were influenced by the fluoride source and synthesis temperature. The F-19 MAS NM R evidence shows the fluorine anion is present in channels of the mordenite crystal as a counterion of cations. Eight mordenite membranes (M-3 serial) prepared using NH4F-modified gels exhibited high fluxes of 1.50 +/- 0.25 kg m(-2) h(-1) together with high separation factors of 1380 +/- 110 for a water/ethanol (10/90 wt.%) mixture at 75 degrees C. The membranes also displayed good water-selective for the water/i-propanol mixture. The high performance is attributed to the thin zeolite layer and good surface hydrophilicity of mordenite membranes prepared in fluoride media. (C) 2012 Elsevier Inc. All rights reserved.