壳聚糖/聚丙烯腈复合纳滤膜制备及脱盐性研究

Study on preparation and desalination of chitosan/polyacrylonitrile composite nanofiltration membranes

为了有效脱除水中阳离子,制备了聚丙烯腈纳滤膜和壳聚糖/聚丙烯腈复合纳滤膜。分别采用热重、红外光谱、扫描电镜和X射线衍射等方法对膜样品的热稳定性、表面官能团、微观形貌以及微结构进行了表征。考察了运行时间、进料浓度、壳聚糖复合等因素对钙离子的截留效果影响。结果显示:壳聚糖与聚丙烯腈膜间复合良好,复合使膜微结构趋于致密;随进料中离子质量浓度升高,纳滤膜对钙离子截留率先增后减;而复合壳聚糖不仅使Ca^2+离子截留率提高到近乎100%,同时也改善了抗污染性。

In order to effectively remove cations from water,polyacrylonitrile nanofiltration membranes and chitosan/polyacrylonitrile composite nanofiltration membranes were prepared.Thermogravimetric analysis,infrared spectra,scanning electron microscope and X-ray diffraction were applied to characterize the thermal stability,surface functional groups,morphology and microstructure of the membrane samples,respectively.The effects of running time,feed concentration,and chitosan compositing on the rejection of calcium ions were investigated.The results show that the composition between chitosan and polyacrylonitrile is quite good,which makes the microstructure of membranes tends to be dense.The rejection first increases and then decreases with feed ion concentration increasing.The chitosan compositing not only elevates the rejection of Ca^2+to near 100%,but also improves the anti-fouling ability.