季铵盐壳聚糖/聚砜复合纳滤膜的制备及性能表征

Preparation and characterization of quaternized chitosan/PS composite nanofiltration membrane

通过涂敷交联法制备了一种新型荷正电纳滤膜,其中以三甲基壳聚糖酰氯(TMC)为膜材料配制铸膜液,以聚砜超滤膜为基膜,环氧氯丙烷为交联剂.试验在全面考察该复合纳滤膜制备工艺基础上,重点探讨了交联时间对复合纳滤膜性能的影响.结果显示:该方法极大地缩短了交联时间,最优交联时间仅为2 h;同时最优条件所制备纳滤膜的纯水透过系数为14.09L/(m^2·h·MPa),表面粗糙度约为4 nm;对无机盐的截留顺序符合以下规律:MgCl_2>NaCl>MgSO_4>Na_2SO_4,满足荷正电纳滤膜的Donnan平衡模型.

A series of novel positively charged nanofiltration membrane having a polysulfone(PS) UF membrane as the substrate were prepared by coating the aqueous solution of trimethyl chitosan chloride (TMC) and subsequently crosslinking with epichlorohydrin(ECH).Besides a comprehensive study on preparation of the NF membrane,the effect of cross-linking time on the performance of composite NF membrane was focused specially.The results suggest that the optimal cross-linking time is only 2 h,which is greatly shortened when compared with other existing research;The pure water permeability of NF membrane is 14.09 L/(m^2·h·MPa),and surface roughness is about 4 nm;The rejection of this membrane to the electrolyte solutions decreases in the order of MgCl_2,NaCl,MgSO_4 and Na_2SO_4,meeting the Donnan equilibrium mode of the positively charged NF membrane.