摘要
以商用PMDA-ODA型聚酰胺酸为涂膜液,采取旋转涂膜技术在煤基板状炭膜支撑体上制备成C/C复合膜。研究了旋转涂膜次数、支撑体性质、支撑体表面预浸渍处理及加入表面改性剂对C/C复合膜气体分离性能的影响,采用扫描电镜对炭膜的复合效果和微结构进行表征。结果表明:随着旋转涂膜次数的增加,气体的渗透速率下降、分离系数增加;与无烟煤支撑体相比,以烟煤支撑体制备的C/C复合膜气体渗透速率和分离系数均较大;无烟煤支撑体经预浸渍处理后可以提高C/C复合膜的气体渗透速率;涂膜液中加入表面改性剂可以改善涂膜液和支撑体的复合效果,经一次涂膜即可制备出具有分子筛分性质的C/C复合膜。以烟煤为支撑体制备的C/C复合膜对H2/N2、CO2/N2和O2/N2的分离系数分别为94.3、18.3和10.2;空气中O2/N2分离系数为10.8,氧气的渗透速率为4.99×10-9m o.lm-.2s-.1Pa-1,一次富集氧气浓度达到74.4%。
Plate-like C/C composite membranes were prepared by spin-coating pyromellitic dianhydride-oxydianiline（PMDA-ODA） polyamic acid（PAA） on membrane supports from bituminous coal and anthracite.The effects of coating time,the properties and pretreatment of the membrane supports,and modification by a blending surface modifier in PAA on the gas separation performance of the membranes were investigated.Scanning electron microscopy was used to characterize the microstructure of the membranes.Results indicate that the single gas permeation rates of the membranes decrease and selectivities increase with an increase in coating time.The gas separation performance of the bituminous coal-based membranes is better than that of anthracite-based ones.The pre-immersion treatment of anthracite supports can greatly improve the gas permeation rate of the membranes.A surface modifier improves the binding strength between the carbon plate and PAA,and membranes with the surface modifier additive exhibit molecular sieving after only one spin-coating.For the bituminous coal-based membranes,the selectivities of H2/N2,CO2/N2,O2/N2 are 94.3,18.3,10.2 respectively,and the selectivity for O2/N2 of air is 10.8 with the O2 permeation rate of 4.99×10-9 mol·m-2·s-1·Pa-1.The O2 concentration can reach 74.4% after one enrichment.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2011年第4期271-277,共7页
New Carbon Materials
基金
国家自然科学基金面上与重点项目(20776024
20976021
20836006)
国家863项目(2009AA03Z215)~~
关键词
C/C复合膜
煤
聚酰胺酸
制备
气体分离
C/C composite membranes
Coal
Polyamic acid
Preparation
Gas separation
作者简介
通讯作者：王同华（1958-），男，山东人，教授，从事炭材料、功能炭材料及膜材料的研究．E-mail：wangth@dlut．edu．cn
