聚酰胺反渗透膜是目前广泛应用的一款商用化水处理膜.然而其表面活性层聚酰胺的结构致密,会导致水通量与截盐率出现"trade-off"现象.针对该问题提出,选择具有多孔结构的、亲水性超交联聚合物复合材料作为添加剂,在界面聚合过程中引入聚酰胺活性层中,为水分子提供更多水通道.同时,纯烃本质的超交联聚合物与聚酰胺的高度相容性,保证了反渗透复合膜的高效截盐性能.经过脱盐性能测试,结果显示添加3.0 mg PDA@HCP-B-SO3H的反渗透复合膜具有最高的水通量为44.4 L·m-2·h-1,截盐率高达99.6％.相比于聚酰胺反渗膜,3.0-PDA@HCP-B-SO3H PA RO的水通量提升了 26.5％,截盐率基本保持不变;相比于只嫁接-SO3H的HCP-B-SO3H PA RO,水通量提升了 11.6％(35.0 L·m-2·h-1上升至39.8 L·m-2·h-1),截盐率基本持平.这说明添加具有多孔结构的、亲水性强的改性超交联聚合物作为添加剂,是一种十分有效地提升聚酰胺反渗透膜性能的方法.
Addition of the Modified Hyper-cross-linked Polymers to Improve the Desalting Performance of Polyamide Composite Reverse Osmosis Membrane
Polyamide reverse osmosis(PA RO)membrane is a kind of commercial water treatment membrane widely used at present.However,the structure of the active layer is dense,which leads to the"trade-off"phenomenon of water flux and salt rejection.To solve this problem,this paper proposes that a hydrophilic hyper-crosslinked polymers with porous structure is selected as an additive to introduce polyamide active layer in the interfacial polymerization process to provide more H2O channels for higher water flux.At the same time,the high compatibility between the pure hydrocarbon hyper-crosslinked polymers and polyamide ensures the efficient salt-rejection performance of the PA RO composite membrane.The results show that the PA RO membrane with 3.0 mg PDA@HCP-B-SO3H has the highest water flux and the salt rejection is as high as 99.6％.Compared with the PA RO membrane,the water flux of 3.0-PDA@HCP-B-SO3H PA RO is increased by 26.5％,and the salt rejection remains basically unchanged.Compared with HCP-B-SO3H grafted with only-SO3H,the water flux increased by 11.6％,and the salt rejection was basically the same.It is obviously shows that the addition of modified hyper-crosslinked polymers with porous structure and strong hydrophilicity is a very effective method to improve the performance of PA RO membranes.
万方数据
维普
