纤维素微纳晶体制备复合超滤膜材料的研究

Preparation of composite ultrafiltration membrane made of cellulose micro/nano crystal

为改善普通聚砜超滤膜水通量低、亲水性差、不耐污染的缺点,该文以纤维素浆粕为原料,通过超声波辅助酸催化水解的方式制得纤维素微纳晶体,并对其性能进行表征;将所得产品和聚砜共混,采用浸没沉淀相转化工艺制备超滤膜材料,测定超滤膜的水通量、截留率、平均孔径、孔隙率、抗张强度等性能。结果表明:随着纤维素微纳晶体用量的增加,超滤膜的水通量逐渐增大;当纤维素添加量与聚砜质量分数达30%时,超滤膜水通量可达234.2L/(m2.h),牛血清蛋白溶液截留率为93.4%。纤维素微纳晶体的加入提高了膜的水通量,明显改善了聚砜超滤膜的性能。此外,通过红外及原子力显微镜对复合超滤膜进行了表征。

The polysulphone uhrafihration membrane has some disadvantages, such as low water flux, bad hydrophile property and anti-fouling ability. In order to conquer these disadvantages, with the cellulose pulp as raw materials, the cellulose micro/nano crystal was prepared by the acid-catalyzed hydrolysis method assisted by the ultrasonic treatment. Its properties were evaluated. Mixing the cellulose micro/nano crystal into the polysulphone membrane, the authors obtained the composite uhrafiltration membrane by the phase inversion via immersion precipitation. The uhrafihration membrane properties were tested. The results show that the pure water flux of uhrafihration membrane increased with the content of cellulose micro/nano crystal increasing. When the mass ratio of the cellulose to polysulphone reached 30%, the composite membrane＇s pure water flux was 234.2 L/m^2 per hour and the preserving ratio of the Bovine Serum Albumin （BSA） solution （1 g/L） was 93.4%. The cellulose micro/nano crystal can increase the pure water flux of the membrane and obviously improve its properties. The composite membrane is also characterized by fast infrared controller and atomic force microscope.