PREPARATION AND CHARACTERIZATION OF THIN-FILM COMPOSITE REVERSE OSMOSIS MEMBRANE ON A NOVEL AMINOSILANE-MODIFIED POLYVINYL CHLORIDE SUPPORT

ABSTRACT Herein, the influence of pure and modified polyvinyl chloride (PVC) support layers on the performance of thin-film composite (TFC) membranes was investigated in water desalination. Accordingly, the PVC support was modified using (3-Aminopropyl) triethoxysilane (APTES) through bulk modification. The supports were synthesized at different doses of APTES (0-6 wt%) and characterized with various analytical techniques. The results showed that APTES affected considerably both the morphology and surface properties of the support layer. Afterwards, the polyamide (PA) layer was formed via an identical interfacial polymerization (IP). The separation experiments showed that modification of the support improved the performance of the TFC membranes, which stems from the improvement in the degree of cross-linking of the PVC structure. At an appropriate condition, permeate fluxes were 0.89 L.m-2.h-1.bar-1 and 2.70 L.m-2.h-1.bar-1for TFC membranes with pure and modified PVC support layers, respectively. Interestingly, there were no significant changes in salt rejection of the prepared membranes.

摘要 本研究以水脱盐过程为应用场景，探究了纯聚氯乙烯（PVC）基底层与改性聚氯乙烯基底层对薄膜复合（TFC）膜性能的影响。据此，研究采用(3-氨丙基)三乙氧基硅烷（APTES）通过本体改性法对PVC基底进行改性。通过调控APTES的添加量（0~6 wt%）制备了一系列PVC基底膜，并利用多种分析表征技术对其进行了表征。结果表明，APTES改性对基底层的形貌与表面性能均具有显著影响。随后，采用统一的界面聚合（IP）工艺制备了聚酰胺（PA）活性层。分离性能实验结果显示，基底改性可有效提升TFC膜的综合性能，该性能提升源于PVC基体交联度的提高。在适宜工艺条件下，纯PVC基底TFC膜与改性PVC基底TFC膜的透水通量分别为0.89 L·m⁻²·h⁻¹·bar⁻¹与2.70 L·m⁻²·h⁻¹·bar⁻¹。值得注意的是，所制备膜的脱盐率未出现显著变化。