ZSM-5分子筛填充壳聚糖膜的制备与性能研究

采用液相共混的方法制备了ZSM-5分子筛填充壳聚糖膜.扫描电镜表征表明分子筛在膜中分散均匀,膜表面没有明显缺陷.考察了填充膜在碳酸二甲酯/甲醇混合液中的溶胀和吸附行为,探讨了填充膜中分子筛含量及操作温度对渗透汽化膜分离性能的影响.结果表明膜优先吸附甲醇,其分离性能主要由溶解过程控制;随着膜中分子筛含量的增加,膜的溶胀度增大,渗透通量大幅度提高;渗透通量与操作温度符合Arrhenius关系式.与壳聚糖均质膜相比,ZSM-5分子筛填充壳聚糖膜对甲醇和碳酸二甲酯混合物具有更好的分离效果.

PREPARATION AND CHARACTERIZATION OF PERVAPORATION MEMBRANES OF ZSM-5 ZEOLITE INCORPORATED CHITOSAN

ZSM-5 zeolite-incorporated chitosan membranes were prepared by the so lution blending method.The membranes were characterized with scanning electron m icroscopy (SEM) to assess their surface morphology.The results showed that zeol ite was uniformly distributed in the membrane matrix and the membranes were fre e of possible defects.Sorption studies indicated that the degree of swelling inc reased w ith the zeolite content,increasing, and the separation selectivity of dimethyl c a rbonate (DMC)/methanol mixtures was dominated by solubility selectivity rather t han diffusivity selectivity.Finally,the effects of zeolite content and operati ng temperature on pervaporation properties were investigated.With increasing the zeolite content,the permeation flux of the membranes increased s ignificantly. From the temperature-dependent permeation values,the Arrhenius activation para meters were estimated.The pervaporation results indicated that the membranes in corporated with the ZSM-5 zeolite exhibited better separation properties for DM C/methanol mixtures comparing with homogeneous chitosan membranes.