氧化石墨烯/聚酰亚胺复合膜的制备及其纳滤分离性能的研究

Preparation of graphene oxide/polyimide composite membrane and its nanofiltration separation performance

本文以均苯四甲基酸酐(PMDA)、4,4-二氨基二苯醚(ODA)作为原料,在合成过程中加入氧化石墨烯进行掺杂,制备出氧化石墨烯/聚酰亚胺复合膜,并考察了其纳滤分离性能。结果表明,在1.6MPa,膜面流速为0.25m·s^(-1),操作温度20℃的条件下,膜通量为46.9L·(m^(2)·h)^(-1),Ca^(2+)、Mg^(2+)截留率分别为91.21%和77.78%;对比相同条件下的纯聚酰亚胺纳滤膜,膜通量提升33.47%,Ca^(2+)、Mg^(2+)截留率分别提升了13.28%和18.98%。因为氧化石墨烯具有很高的比表面积,并且在表面具有大量的亲水基团等特殊结构,所以通过掺杂可以明显提高聚酰亚胺纳滤膜的分离性能。

In this paper,graphene oxide/polyimide composite membrane was prepared by doping graphene oxide with pyromellitic PMDA and ODA as raw materials,and nanofiltration separation performance of the membrane was investigated.The result showed that the membrane flux was 46.9L·(m^(2)·h)^(-1)at 1.6MPa and the membrane surface velocity was 0.25m·s^(-1),and the operating temperature was 20℃,the rejection rates of Ca^(2+)and Mg^(2+)were91.21%and 77.78%.Compared with the pure polyimide nanofiltration membrane under the same conditions,the membrane flux increased by 33.47%,and the rejection of Ca^(2+)and Mg^(2+)increased by 13.28%and 18.98%.Because graphene oxide has a high specific surface area and a large number of hydrophilic groups and other special structures on the surface,so the separation performance of polyimide nanofiltration membrane can be significantly improved by doping graphene oxide.