具有不同取代基数量铁酞菁衍生物改性双极膜的性能研究

摘要

Iron phthalocyanines ( Pc ) with different quantities of carboxyl groups were added into carboxy-methylcellulose (CMC) cation exchange membrane to prepare the modified CMC/CS bipolar membranes (BPMs,CS: chitosan). Results showed that after modification by iron phthalocyanines, the ion exchange capacity and hydrophilicity of CMC membrane and the mechanical properties of the BPM increased, and the swelling degrees of the BPM decreased. Furthermore, a high charge density area formed in the inter-layer of the BPM after modification, which sped up water dissociation, lowered the membrane impedance and the cell voltage. At the current density of 60 mA/cm2, the cell voltages of Fe2Pc2 (COONa) 12-CMC/ CS BPM,FePc( COONa)8-CMC/CS BPM,FePc( COONa)4-CMC/CS BPM and CMC/CS BPM were 5.6, 6.2,6.5 V and 8.9 V respectively.%分别用具有不同取代基数量铁酞菁衍生物加入羧甲基纤维素钠(CMC)阳离子交换膜中,制备改性的CMC/CS双极膜(BPM,CS∶壳聚糖).结果表明,经铁酞菁改性后,阳膜的离子交换容量、亲水性和双极膜的机械性能均获得提高,双极膜的溶胀度下降.此外,改性后,铁酞菁衍生物可在双极膜中间界面层形成高荷电区,促进水解离,降低膜阻抗和槽电压.当电流密度为60 mA/cm2时,Fe2Pc2(COONa) 12-CMC/CS BPM,FePc(COONa) 8-C MC/CS BPM,FePc (COONa)4-CMC/CS BPM和CMC/CS BPM的膜电压分别为5.6,6.2,6.5,8.9V.