Experimental investigation and thermodynamic study of heavy metal removal from industrial wastewater using pomegranate peel

Abstract

The objective of the study is to treat industrial wastewater and perform a thermodynamic experimental study for more economical and efficient adsorption process. This has been done by biosorption and chemisorption of chromium ions from synthetic wastewater into already prepared pomegranate peel as a natural adsorbent. Pomegranate peel proved to be an economic solution since it is available locally and it has an elevated adsorption capacity. Adsorption has been done in a fixed bed column (10 cm inside diameter, and 30 cm height) with continuous flow rate of 1 ml/min. The characteristic properties of adsorption for the pomegranate peel, analyzed by FTIR and SEM, proved that pomegranate peel is a good adsorbent because of its effective combinations and holes on its exterior. Also, comparing between adsorption ability of pomegranate peel together with Langmuir and Freundlich models indicates that Langmuir is preferable in fitting the experimental data. However, the elimination efficiency of the pomegranate peel was 90%, and the greatest adsorption capability was 9.45 mg/g. While, thermodynamic study results showed that endothermic adsorption was approved from positive values of ΔH°, also the negative values of ΔG° proved that the adsorption is unprompted and convenient.