海藻酸纤维对水溶液中Fe~(3+)的吸附动力学研究

以海藻酸纤维作为吸附材料研究了纤维对水溶液中Fe3+的吸附性能,用准一级动力学方程、准二级动力学方程、Elovich方程、粒子扩散方程、双常数方程和指数函数方程数学模型对不同Fe3+浓度、吸附时间的吸附曲线进行分析,研究了其吸附的动力学机理。结果表明:在研究的浓度和条件范围内,准二级动力学模型、Elovich方程和双常数方程的拟合度较好,模拟值与实验值吻合较好,说明海藻酸纤维吸附Fe3+是复杂的非均相扩散的化学吸附过程。粒子扩散方程表明颗粒内扩散不是控制海藻酸纤维吸附Fe3+过程的唯一步骤,而是由膜扩散和颗粒内扩散联合控制。

Adsorption kinetic studies of Fe3+ onto alginic acid fiber from aqueous solution

The adsorption property of alginic acid fiber for Fe3+ in aqueous solution were studied.The adsorption curves were analyzed at different Fe3+ concentration and adsorption time using Lagergren-first order kinetic equation,Lagergren-second order kinetic equation,Elovich equation,intraparticular diffusion equation,double constant euqation and index function equation.The kinetic adsorption mechanism was studied.The results showed that the Lagergren-second-order equations,Elovich equation and double constant equation were fit well and a good agreement between the calculated and experimental data was obtained,which indicated that the adsorption of Fe3+ on alginic acid fiber is a complex heterogeneous diffusion chemical adsorption process.The intraparticular diffusion equation indicated that the adsorption rate of Fe3+ on alginic acid fiber was not controlled by the intraparticle diffusion only,but by the combination of film diffusion and intraparticle diffusion.