Reverse Micellar Extraction of Copper Ions from Wastewater: Modelling and Simulation

Abstract

The waste streams from various agencies like textile, leather, electroplating, and process industries are generating pollutants in the form of effluents or by products. These waste streams consist of various carcinogenic pollutants such as dyes and heavy metals above the permissible limits. Numerous effluent treatment techniques have been implemented for the removal of these pollutants before their discharge into the water body. In this work, reverse micellar extraction was used for the removal of copper ions (heavy metal ions) from the waste stream. Mathematical models namely, the ion exchange reaction model and electrostatic model were developed in order to compare the experimental data with model predictions with regard to the effect of process parameters such as initial metal ion concentration, sodium bis-2-ethyl hexyl sulphosuccinate (AOT) concentration, and organic to aqueous phase volume ratio on final copper ion concentration in the aqueous phase. The ion exchange reaction model was based on chemical and electrostatic interactions between heavy metal ions and the surfactant head groups at the reverse micellar interface, whereas the electrostatic model was based on the adsorption of metal ions on the reverse micellar interface due to electrostatic force of attraction with no chemical bonding. The developed mathematical models were found in close agreement with the experimental data. Atomic absorption spectroscopy (AAS) was used to measure the metal ion concentration in the aqueous phase.