耐高温PBI基质子-电子混合传导复合膜的构制及其氢渗透性能研究

Preparation of protonic-electronic mixed conducting PBI-based composite membrane with high-temperature tolerance and its hydrogen permeation

以3,3′-二氨基联苯胺(DABz)和间苯二甲酸(IPA)为原料,采用熔融聚合法合成了低分子量可耐高温的聚[2,2′-(间苯基)-5,5′-联苯并咪唑](mPBI)有机膜材料;以异氰尿酸三缩水甘油酯(TGIC)为交联剂,并浸渍磷酸提供质子传导路径,添加片状石墨作为电子导体,得到质子-电子混合导体mPBI-TGIC/石墨/H3PO4交联复合膜.对交联复合膜进行结构和性能表征,结果表明交联复合膜具有良好的机械性能和抗氧化稳定性.用于H2/CO2混合气体分离,300℃时,H2选择性高达100%,渗透量为4.93×10^-9 mol/(m^2·s·Pa);280℃时,可稳定运行160 h.表明mPBI-TGIC/石墨/H3PO4交联复合膜具有良好的耐高温性,有望用于工业高温气体的分离.

Based on 3,3′-diaminobenzidine(DABz)and isophthalic acid(IPA)as raw materials,poly[2,2′-(m-phenyl)-5,5′-bibenzimidazole](mPBI)with low molecular weight has been synthesized by the“melt polymerization method”.The mPBI TGIC/graphite/H3PO4 cross-linked composite membrane has been obtained using triglycidyl isocyanurate(TGIC)as cross-linking agent and flake graphite as electronic conductor combining with impregnated phosphoric acid.The structural and performance characterization of the cross-linked composite membrane show that the cross-linked composite membrane has good mechanical properties and anti-oxidation stability.For separation of H2/CO2 mixed gas,the hydrogen selectivity is up to 100%,and the permeation flux is 4.93×10^-9 mol/(m^2·s·Pa)at 300℃.The 160 h long-term stability at 280℃indicates that mPBI TGIC/graphite/H3PO4 cross-linked composite membrane has good high temperature resistance and applicable for high-temperature hydrogen separation.