Adsorption studies of pomegranate peel activated charcoal for nickel (II) ion

Abstract

Presence of toxic heavy metals in air, soil, and water are growing threats to the environment. In this study, removal of divalent nickel from aqueous solutions has been investigated by utilizing a low cost pomegranate peel activated charcoal (PPAC) adsorbent. Adsorption capacity of the prepared charcoal at various parameters such as pH, contact time, metal ion concentration and adsorbent dose has been studied. Batch equilibrium experiments showed that maximum nickel adsorption takes place at neutral pH, while the maximum adsorption capacity for PPAC was 10.82 mg g-1. It was also found that percentage removal of nickel is directly proportional to the adsorbent dose with maximum adsorption at an adsorbent dose of 0.5g/50 ml for various concentrations (10-150 ppm) and contact time of 50 minutes. Experimental equilibrium data was verified for Langmuir and Freundlich isotherm models to establish the adsorbate-adsorbent interaction phenomena. The values of regression coefficient for Langmuir and Freundlich isotherm are found to be 0.942 and 0.931 respectively which showed that data fitted well in both models.