Modeling of copper ion removal from aqueous solutions using modified silica beads

Silica beads, containing 2-hydroxy-5-nonylacetophenoncoxime (LIX84) were prepared in order to examine the removal of copper ions from aqueous waste solutions. The process for copper ion removal using the modified silica beads was mathematically modeled using both a nonequilibrium model and an equilibrium model. The external mass transfer coefficient and effective diffusivity inside the bead pore were estimated by matching the experimental data and predicted values from the model, and the results were compared. The results of the two models were similar and in good agreement because of the relatively faster reaction rate than mass transfer rate. Sensitivity analyses showed that the external mass transfer has more influence on the copper ion removal system because of hydrophobic effects.