201×7树脂对铁氰络合物的吸附动力学

Adsorption kinetics of 201 × 7 resin for iron cyanocomplexes

对201×7树脂吸附铁氰化合物的过程进行动力学研究。结果表明，201×7树脂对铁氰化合物有很好的吸附效果。在298K时，201×7树脂对亚铁氰化络合离子[Fe（CN）6]^4-和铁氰化络合离子[Fe（CN）6]^3-的静态饱和吸附量分别为8．620和12．072mg／mL。用均相颗粒扩散模型和收缩核模型对吸附参数进行描述，表明201×7树脂对[Fe（CN）6]^3-和[Fe（CN）6]^4-的吸附过程均属于液膜扩散控制。由树脂对[Fe（CN）6]^4-和[Fe（CN）6]^3-的等温吸附线得到Freundlich常数n分别为4．786和6．145：吸附过程中分离系数S和选择系数K均大于1，表明201×7树脂对[Fe（CN）6]^4-和[Fe（CN）6]^3-两种络合离子都是容易吸附的，而且[Fe（CN）6]^3-离子比[Fe（CN）6]^4-离子更容易被吸附。

Kinetics measurements on the adsorption of iron cyanocomplexes with the 201 × 7 ion-exchange resin were investigated. The results show that the 201 × 7 resin has good adsorption ability for iron cyanocomplexes. The static saturated adsorptive capacity at 298 K is 8.620 and 12.072 mg/mL for ferrocyanide [Fe（CN）6]^4- and ferdcyanide [Fe（CN）6]^3-, respectively. Analyses of the respective rate data in accordance with homogeneous particle diffusion model and shell progressive model are used to explain the ions adsorption kinetics, which indicates that the controlling step of adsorbing [Fe（CN）6]^3- and [Fe（CN）6]^4- is liquid film diffusion. Isotherm adsorption curves deduce that Freundlich constant, n, is 4.786 and 6.145 for [Fe（CN）6]^4- and [Fe（CN）6]^3-, respectively. In adsorption process, the separation factor S and selectivity coefficient K are both greater than 1. The facts indicate that both [Fe（CN）6]^4- and [Fe（CN）6]^3- are easily adsorbed on 201 × 7 resin, furthermore, the adsorption of [Fe（CN）6]^3- on 201 × 7 resin is easier than that of [Fe（CN）6]^4-.