ABSTRACT

Post treatment is a very competent and scalable approach to develop the higher water-flux and salt-rejection membrane since it does not require any change in existing manufacturing process. The virgin Thin Film Composite Reverse Osmosis (TFC-RO) membrane was exposed to various concentrations of Poly (ethylene Glycol) diacrylate (PEGDA) and Ethylene glycol dimethacrylate (EGDMA) after activation with sodium hypochlorite for 1 h. Crosslinkers modified membranes were characterized for degree of wettability by contact angle analyses, surface morphology and surface roughness study by Scanning electron micrographs and Atomic force micrographs, chemical structural modifications by Attenuated total reflectance Fourier transform Infrared spectroscopy. These treatments resulted in improved membrane performance. 3500 mg/l PEGDA-treated membrane permeate flux increased by 48.7% and salt-rejection by 3.43%. 2000 mg/l EGDMA treated membrane demonstrated 46.13% increase in water-flux and 3.08% increase in salt-rejection as compared with virgin membrane. Organic fouling study indicated that fouling in PEGDA-treated membrane was significantly lower than virgin membrane. Heavy metal ion removal performances for Zinc and Chromium were also higher for modified membranes. Thus, the surface modification by crosslinkers led to increase in selectivity for certain metal ions and better antifouling performance as compared to virgin membrane.

摘要

后处理是开发更高水通量和脱盐膜的一种非常有效且可扩展的方法，因为它不需要对现有制造工艺进行任何更改。在用次氯酸钠活化 1 小时后，将原始薄膜复合反渗透 (TFC-RO) 膜暴露于不同浓度的聚 (乙二醇) 二丙烯酸酯 (PEGDA) 和乙二醇二甲基丙烯酸酯 (EGDMA)。通过接触角分析，通过扫描电子显微照片和原子力显微照片对表面形态和表面粗糙度进行研究，通过衰减全反射傅里叶变换红外光谱对化学结构改性，对交联剂改性膜的润湿程度进行表征。这些处理导致改进的膜性能。3500 mg/l PEGDA 处理的膜渗透通量增加了 48.7%，脱盐率增加了 3.43%。与原始膜相比，经 2000 mg/l EGDMA 处理的膜的水通量增加了 46.13%，脱盐率增加了 3.08%。有机污染研究表明，PEGDA 处理的膜中的污染明显低于原始膜。改性膜对锌和铬的重金属离子去除性能也更高。因此，与原始膜相比，交联剂的表面改性提高了对某些金属离子的选择性和更好的防污性能。有机污染研究表明，PEGDA 处理的膜中的污染明显低于原始膜。改性膜对锌和铬的重金属离子去除性能也更高。因此，与原始膜相比，交联剂的表面改性提高了对某些金属离子的选择性和更好的防污性能。有机污染研究表明，PEGDA 处理的膜中的污染明显低于原始膜。改性膜对锌和铬的重金属离子去除性能也更高。因此，与原始膜相比，交联剂的表面改性提高了对某些金属离子的选择性和更好的防污性能。