Pervaporation of organic/water mixtures through B-ZSM-5 zeolite membranes on monolith supports
Pervaporation of organic/water mixtures through B-ZSM-5 zeolite membranes on monolith supports
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DOI：
10.1016/s0376-7388(02)00617-8
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发表时间：
2003-04-15
影响因子：
9.5
通讯作者：
Noble, RD
中科院分区：
文献类型：
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作者：
Bowen, TC;Kalipcilar, H;Noble, RD
在Al 2 O3包覆的SiC多通道载体上制备了高质量的硼取代ZSM-5沸石膜。整料具有比管状载体更大的表面积与体积比，并且对于大规模应用更实用。使用具有66个通道（2 mm × 2 mm，10.6cm（2）表面积cm（-3））和22个通道（4 mm × 4 mm，7.2cm（2）cm（-3））的两种类型的支持物。所述膜有效地从5重量%的乙醇和丙酮中去除乙醇和丙酮。在303-333 K的温度范围内通过渗透蒸发有机/水二元进料。的膜是选择性的，因为丙酮和醇优先吸附和抑制水的运输，但不同的吸附强度和分子大小所造成的扩散差异也很重要。对极性分子动力学直径的计算方法进行了比较。丙酮/水分离因子在303 K时为330，在333 K时下降到220。甲醇，乙醇，2-丙醇，和1-丙醇的分离因子分别为8.4，31，42，和75，在333 K和相对独立的温度。除甲醇外，这些分离因子明显高于B-ZSM-5管式膜的分离因子。在333 K时，甲醇、乙醇、1-丙醇、2-丙醇和丙酮的通量分别为0.90、0.16、0.047、0.071和0.22 kg m（-2）h（-1），并随温度升高而增加。甲醇和乙醇通量与B-ZSM-5管式膜的那些相当。(C)2003 Elsevier Science B. V.保留所有权利。
High-quality, boron-substituted ZSM-5 zeolite membranes were prepared on Al2O3-coated SiC multi-channel monolith supports. Monoliths have larger surface to volume ratios than tubular supports and are more practical for large-scale applications. Two types of supports with 66 channels (2 mm x 2 mm, 10.6 cm(2) surface area cm(-3)) and 22 channels (4 mm x 4 mm, 7.2 cm(2) cm(-3)) were used. The membranes effectively removed alcohols and acetone from 5 wt.% organic/water binary feeds by pervaporation over a temperature range of 303-333 K. The membranes were selective because acetone and the alcohols preferentially adsorbed and inhibited water transport, but diffusion differences caused by different adsorption strengths and molecular sizes were also important. Methods for calculating molecular kinetic diameters for polar molecules are compared. The acetone/water separation factor was 330 at 303 K, and it decreased to 220 at 333 K. Methanol, ethanol, 2-propanol, and 1-propanol separation factors were 8.4, 31, 42, and 75, respectively, at 333 K and were relatively independent of temperature. With the exception of methanol, these separation factors are significantly higher than those reported for a B-ZSM-5 tubular membrane. The fluxes at 333 K were 0.90, 0.16, 0.047, 0.071, and 0.22 kg m(-2) h(-1) for methanol, ethanol, 1-propanol, 2-propanol, and acetone, respectively, and increased with temperature. The methanol and ethanol fluxes are comparable to those for the B-ZSM-5 tubular membrane. (C) 2003 Elsevier Science B.V. All rights reserved.