Biosorption of Rubber Seed Shell as a Waste Material in the Removal of Cadmium Ion from Contaminated Water

Abstract

Heavy metal ion contamination in industrial wastewater is a major source of concern. Among the numerous approaches, biosorption has attracted the greatest attention in the removal of heavy metal ions from water. In particular, cadmium is bio-accumulative that poses a threat to our health when it exists in excess in our bloodstream. Here, the elimination of Cd (II) ions from wastewater using adsorbent derived from rubber seed shell (RSS). Further, thermogravimetric analysis was performed to determine the stability of materials. According to the hard and soft acids and bases (HSAB) principle, the rubber seed shell as novel bioadsorbent creates hard surface sites for cadmium ion adsorption. Batch experiments were carried out to determine the effects of pH, contact time, initial metal ions concentration, and biosorbent dosage on the removal efficiencies of Cd2+ ion using rubber seed shell. Adsorption isotherms and kinetics models were also performed for the elimination of Cd2+ ion. The optimum conditions was conducted and achieved 96% removal efficiencies of Cd2+ ion from water (pH 5.6, temperature 60°C, and initial metal concentration of 150 mg/L, the adsorption dosage 180 mg/g). The outcome of the present investigations indicated that the increasing use of bioadsorbent materials due to their low cost, regeneration ability, high adsorption efficiency, and higher removal percentage of metal ions from water sources.