Modeling of mass transfer of uranium on different nanoadsorbents for the remediation of contaminated aquatic system

摘要

Iron oxides, as a group, have important applications as pigments, catalysts, gas sensors, magnetic recording media, etc. Among these iron oxides, akaganeite (-FeOOH) and goethite (-FeOOH) have attracted much investigation because of its unique sorption, ion exchange, and catalytic properties. The present study on uranium transport through akaganeite and goethite has been performed using batch experiments. The transport mechanism of uranium which comprises a diffusion process from aqueous phase on akaganeite and goethite was described by two kinetic models consisting of derived equations: the homogenous particle diffusion model (HPDM) and the shell progressive model (SPM). It was confirmed that the process was controlled by diffusion rate of uranium that penetrated the reacted layer at uranium concentrations in range of 75-150mg/L. The effective particle diffusion coefficient D-eff values were calculated from both the HPDM and SPM equations. The theory-experiment comparison has revealed that predicted values are in excellent agreement with the experimental values.