Trgo M, Perić J, Medvidović N Vukojević
Faculty of Chemical Technology, University of Split, Teslina 10/V, 21000 Split, Croatia.
J Environ Manage. 2006 May;79(3):298-304. doi: 10.1016/j.jenvman.2005.07.009. Epub 2005 Oct 26.
The kinetics of uptake of zinc ions from aqueous solutions by natural zeolitic tuff has been investigated. Batch experiments at constant temperature and hydrodynamic conditions have been performed. A decrease in the initial zinc concentration in aqueous solutions prolongs the time needed for equilibrium. Various kinetic models including the film-diffusion model, the surface diffusion model and the heterogeneous diffusion model have been tested for the description of the experimental results of zinc concentration in the solution over time. Diffusion through the film and diffusion through the surface of the particle could be the rate limiting steps at the initial reaction time. However, the heterogeneous diffusion model seems to be the best model providing a satisfactory fitting of the experimental results from the beginning of the process to the point of equilibrium, particularly at lower initial zinc concentrations.
研究了天然沸石凝灰岩从水溶液中吸收锌离子的动力学。在恒定温度和流体动力学条件下进行了间歇实验。水溶液中初始锌浓度的降低延长了达到平衡所需的时间。为了描述溶液中锌浓度随时间变化的实验结果，测试了包括膜扩散模型、表面扩散模型和非均相扩散模型在内的各种动力学模型。在初始反应时间，通过膜的扩散和通过颗粒表面的扩散可能是速率限制步骤。然而，非均相扩散模型似乎是最好的模型，从过程开始到平衡点都能令人满意地拟合实验结果，特别是在较低的初始锌浓度下。
