四价钒离子VO^(2+)在几种阳离子交换膜中的自扩散行为

Self-diffusion behaviour of VO^(2+) in several cation exchange membranes

研究了VO2+在3种阳离子交换膜PE01,NF120以及Nafion1135中的自扩散行为,采用UV-3802可见-紫外分光光度仪测定VO2+浓度,建立浓度与时间的关系,用Ct=Ct∞(1-exp(-αt))经验方程拟合实验数据,得到VO2+在3种膜PE01,NF120以及Nafion1135中的自扩散方程.结合Fick扩散理论,推导出了VO2+在膜中的扩散系数D与方程中经验常数α的关系,计算出了VO2+在3种阳离子交换器Nafion1135,PE01以及NF120中的扩散系数分别为2.66×10-13,2.09×10-13和3.26×10-13m2/s.在所研究的阳离子交换膜中,PE01膜对VO2+具有最好的阻隔作用.

The self-diffusion behaviour of VO^(2+) in several cation exchange membranes PE01,NF120 and Nafion1135 were studied.A UV-Vis spectrometer was used to determine the concentration of VO^(2+) in the diffusion cell,and the relationship of the concentration of the diffused ion VO^(2+) and diffusion time was established.These C～t relation curves can be represented by a general experimental equation C_(Rt)=C_(Rt∞)[1-(exp(αt)]) with different α value,thus obtained three equations for VO^(2+) diffusion in different membranes.According to the Fick diffusion theory, the relation between experiment parameter α and the diffusion coeffcients D of VO^(2+) in different membranes was obtained,2.66×10^(-13),2.09×10^(-13) and 3.26×10^(-13) m^2/s for VO^(2+) in PE01,NF120 and Nafion1135 membrane respectively.In the studied membranes,PE01 has the highest ability for retarding VO^(2+) across the membrane.