添加磁性纳米粒子制备气体分离功能炭膜

以聚酰胺酸为炭膜前驱体,分别以Fe_3O_4、γ-Fe_2O_3、Zn_(0.5)Ni_(0.5)Fe_2O_4以及二茂铁为掺杂物,经高温热解制备了4种Fe系物质掺杂的气体分离功能炭膜,对所制备的功能炭膜微结构及磁性能进行了表征.结果表明,各掺杂物在热解炭化过程中发生了物相结构的变化,其中Fe_3O_4和Zn_(0.5)Ni_(0.5)Fe_2O_4纳米粒子对前驱体起到了催化石墨化的作用.气体渗透测试结果表明,各掺杂物所制备的功能炭膜以分子筛分机理为主导进行气体分离,且气体渗透性能都有了显著的提高,特别是小分子气体H2渗透性最大提高了近48倍,Fe3O4掺杂所制备的功能炭膜,其H_2、CO_2、O_2、N_2和CH_4等单组分气体的渗透系数分别达到了12 194、3 433、1 175、136和74 Barters1Barter=1×10~(-10)cm~3(STP)·cm/cm~2·s·cmHg].经FeO_4、γ-Fe_2O_3和Zn_(0.5)Ni_(0.5)Fe_2O_4掺杂制备的功能炭膜更是提高了H_2/CO_2的分离选择性.

Functional carbon membranes fabricated by doping magnetic nanoparticles for gas separation

Functional carbon merrIbranes for gas separation are designed and prepared by incorporating Fe_3O_4,γ-Fe_2O_3,Zn_(0.5)Ni_(0.5)Fe_2O_4 nanoparticles into carbon membrane precursor polyimide,as well as fermeene.The synthesized membranes are characterized.Results show that all the doponts have changed into other phase morphologies during the pyrolysis process,while Fe_3O_4 and Zn_(0.5)Ni_(0.5)Fe_2O_4 nanoparticles are influential in the formation of graphite-like layers.Gas permeation test results show that all the functionl carbon membranes exhibite an outstanding molecular sieving capability together with high gas permeability,especially to micromolecule gas H2 whose permeability is increased by 48 times at most.The permeabilities of pure gas H_2,CO_2,O_2,N_2,CH_4 in functional carbon membrane doping with Fe_3O_4 are 12 194,3 433,1 175,136,74 Barrers γ-Fe_2O_3 and Zn_(0.5)Ni_(0.5)O_4 have an improved selectivity in sepemting H_2 and CO_2.