Fe3O4掺杂制备气体分离功能炭膜  

Polymide/Fe_3O_4-carbonized Membranes for Gas Separation

作　　者：赵选英[1] 王同华[1] 李琳[1] 刘颖[1] 曹义鸣[2] 

机构地区：[1]大连理工大学化工学院材料化工系精细化工国家重点实验室,炭素材料实验室,大连116012 [2]中国科学院大连化学物理研究所,大连116023

出　　处：《无机材料学报》2010年第1期47-52,共6页Journal of Inorganic Materials

基　　金：国家自然科学基金面上与重点项目(20776024,20836006)

摘　　要：采用共混法在聚酰亚胺前驱体中引入Fe3O4纳米粒子,经高温热解炭化制备了杂化功能炭膜.采用XRD、TEM和VSM等分析方法对所制备的功能炭膜进行表征,并探讨了Fe3O4纳米粒子的掺杂量及炭化终温对功能炭膜气体分离性能的影响.结果表明,Fe3O4纳米粒子在热解炭化过程中发生了物相形态的改变,并对前驱体起到了催化石墨化的作用,使功能炭膜具有类石墨片层和乱层炭的两种炭结构形态,同时具有磁性.气体渗透实验表明,掺杂Fe3O4纳米粒子使所制备的功能炭膜具有"分子筛分"的分离特征,提高了炭膜的气体渗透性能,特别是对小分子气体H2的渗透性提高了61倍,H2/CO2的分离选择性也明显得到改善.Fe3O4的掺杂量和炭化终温对炭膜的气体分离性能有显著影响.Fe3O4添加量为20wt%的功能炭膜对H2、CO2、O2、N2和CH4等纯气体的渗透系数分别为15476、4385、1565、193和114Barrers[1Barrer=1×10-10cm3(STP).cm/(cm2.s.cmHg)].Novel functional carbon membranes for gas separation were designed and prepared by incorporating Fe_3O_4 nanoparticles into carbon membranes precursor polyimide.The as-synthesized membranes were characterized by TEM,XRD and VSM.The effects of Fe_3O_4 addition and the final pyrolysis temperature on the gas permeability were investigated.The results show that Fe_3O_4 nanoparticles transformed into other phase morphologies are helpful to form the graphite-like layers during the pyrolysis process,which make the membrane with two types of carbon structure ： amorphous carbon and graphite-like layers.All the functional carbon membranes exhibit magnetism.Single gas permeation test results show that the as-synthesized membranes exhibit an outstanding molecular sieving capability together with high gas permeability.The gas permeability of H2 is 61 times higher than the pure carbon membrane and the H2/CO2 selectivity is also improved.Fe_3O_4 addition and the final pyrolysis temperature siginificantly impair the gas permeability.When the Fe_3O_4 content is 20wt%,the permeabilities of pure gas H2,CO2,O2,N2,CH4 in the functional carbon membrane are 15476,4385,1565,193 and 114 Barrers（1Barrer=1×10-10 cm3（STP） ·cm/（cm2·s·cmHg））,respecticvely.The final pyrolysis temperature also has a remarkable effect on the gas separation performance.

关 键 词：磁性 功能炭膜 气体分离 渗透性能 

分 类 号：TQ028[化学工程]