多壁碳纳米管(MWNT)经硫酸/硝酸混酸处理后，获得的羧基化多壁碳纳米管通过溶液共混制备了羧基化多壁碳纳米管/壳聚糖(MWNT-COOH/CS)杂化膜，用于乙醇/水体系的渗透汽化脱水。采用FTIR、TEM等表征了混酸处理前后的多壁碳纳米管及杂化膜的结构，实验测定了杂化膜在乙醇/水溶液中的溶胀吸附行为及其对乙醇/水体系的渗透汽化性能。结果表明：(1)多壁碳纳米管经混酸处理后在杂化膜中的分散性大大改善；(2)和乙醇相比，杂化膜对水具有优先吸附、溶胀特征，且随MWNT-COOH填充量的增加，杂化膜在乙醇/水溶液中的平衡溶胀度增大，水和乙醇在杂化膜中的扩散系数增大；(3) 对于90wt％的乙醇/水体系，杂化膜表现出较好的渗透汽化脱水性能，杂化膜的渗透通量随MWNT-COOH填充量的增加而增大，而分离因子略有下降。

multi-walled carbon nanotube(MWNT) was modified by H2SO4/HNO3 mixture and then loaded into chitosan(CS) to prepare MWNT-COOH/CS hybrid membrane for pervaporation dehydration of ethanol/water mixtures. The structure of MWNT、MWNT-COOH and hybrid membrane were characterized by transmission electron microscopy(TEM) and FTIR, and the results show that the modification of MWNT promoted the dispersion of MWNT-COOH in the membrane matrix. The diffusion coefficient of water in the hybrid membrane was higher than that of ethanol, diffusion selectivity(αD,w/e) and solubility selectivity(αS,w/e) increased with the increasing MWNT-COOH content in the membrane matrix based on the sorption experiment. For pervaporation of 90wt% ethanol/water mixtures, the permeation flux of the hybrid membrane increased, selectivity (αw/e) slightly decreased with the increasing MWNT-COOH content in the membrane matrix.

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