CJMAED™ 均相阴离子交换膜在氯化钠和硫酸钠溶液中的传输特性。
Transport Characteristics of CJMAED™ Homogeneous Anion Exchange Membranes in Sodium Chloride and Sodium Sulfate Solutions.
机构信息
Membrane Institute, Kuban State University, 149 Stavropolskaya St., 350040 Krasnodar, Russia.
CAS Key Laboratory of Soft Matter Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials, School of Chemistry and Material Science, University of Science and Technology of China, Hefei 230026, China.
出版信息
Int J Mol Sci. 2021 Jan 31;22(3):1415. doi: 10.3390/ijms22031415.
The interplay between the ion exchange capacity, water content and concentration dependences of conductivity, diffusion permeability, and counterion transport numbers (counterion permselectivity) of CJMA-3, CJMA-6 and CJMA-7 (Hefei Chemjoy Polymer Materials Co. Ltd., China) anion-exchange membranes (AEMs) is analyzed using the application of the microheterogeneous model to experimental data. The structure-properties relationship for these membranes is examined when they are bathed by NaCl and NaSO solutions. These results are compared with the characteristics of the well-studied homogenous Neosepta AMX (ASTOM Corporation, Japan) and heterogeneous AMH-PES (Mega a.s., Czech Republic) anion-exchange membranes. It is found that the CJMA-6 membrane has the highest counterion permselectivity (chlorides, sulfates) among the CJMAED series membranes, very close to that of the AMX membrane. The CJMA-3 membrane has the transport characteristics close to the AMH-PES membrane. The CJMA-7 membrane has the lowest exchange capacity and the highest volume fraction of the intergel spaces filled with an equilibrium electroneutral solution. These properties predetermine the lowest counterion transport number in CJMA-7 among other investigated AEMs, which nevertheless does not fall below 0.87 even in 1.0 eq L solutions of NaCl or NaSO. One of the reasons for the decrease in the permselectivity of CJMAED membranes is the extended macropores, which are localized at the ion-exchange material/reinforcing cloth boundaries. In relatively concentrated solutions, the electric current prefers to pass through these well-conductive but nonselective macropores rather than the highly selective but low-conductive elements of the gel phase. It is shown that the counterion permselectivity of the CJMA-7 membrane can be significantly improved by coating its surface with a dense homogeneous ion-exchange film.
使用微相分离模型对实验数据进行分析,研究了 CJMA-3、CJMA-6 和 CJMA-7(中国合肥科聚先进材料股份有限公司)阴离子交换膜(AEM)的离子交换容量、含水量和电导率、扩散渗透率以及反离子迁移数(反离子选择透过性)的浓度依赖性之间的相互作用。当这些膜被 NaCl 和 NaSO 溶液浸泡时,研究了这些膜的结构-性能关系。将这些结果与研究充分的均质 Neosepta AMX(ASTOM 公司,日本)和非均质 AMH-PES(Mega a.s.,捷克共和国)阴离子交换膜的特性进行了比较。结果发现,在 CJMAED 系列膜中,CJMA-6 膜具有最高的反离子选择透过性(氯化物、硫酸盐),非常接近 AMX 膜。CJMA-3 膜具有与 AMH-PES 膜相近的传输特性。CJMA-7 膜的交换容量最低,凝胶相内充满平衡电中性溶液的空间的体积分数最高。这些特性决定了在研究的其他 AEM 中,CJMA-7 中的反离子迁移数最低,即使在 1.0 eq L 的 NaCl 或 NaSO 溶液中也不低于 0.87。CJMAED 膜选择透过性降低的原因之一是扩展的大孔,这些大孔位于离子交换材料/增强布的边界处。在相对浓度较高的溶液中,电流更倾向于通过这些导电性好但非选择性的大孔,而不是凝胶相的高选择性但低导电性的部分。结果表明,通过在 CJMA-7 膜的表面涂覆致密均相离子交换膜,可以显著提高其反离子选择透过性。