Removal of Lead and Cadmium ions from Wastewater by Using Eco-friendly Nanocomposite

Abstract

Eco-friendly nanocomposite (HS) was prepared from agriculture sources and characterized for remediation of wastewater from lead and cadmium ions. The nanocomposite was prepared from humic acid with silica (HS) which was prepared from compost and rice husk. The nanocomposite was characterized by FTIR, XRD, SEM, Zeta potential, BET and SEM-EDX. The removal of metal ions was studied using a variety of operating parameters, including pH, metal ion concentration, adsorbent dosage, and contact time. In both Pb 2+ and Cd 2+ , the best removal efficiency was found at pH 5.6 and 6. Pb 2+ and Cd 2+ had equilibrium times of 30 and 60 minutes, respectively. The adsorption process was exothermic and spontaneous in nature, according to thermodynamics. In terms of describing and evaluating the adsorption process, the Langmuir, Freundlich, and Temkin models are the most accurate, according to isotherm adsorption studies. Nanocomposite (HS) before and after adsorption was confirmed by EDX to involve lead and cadmium ions. The adsorption capacity of HS was 22.86 and 6.25 mg/g for Pb 2+ and Cd 2+ , respectively.