Biosorptive removal of Pb(II) and Cd(II) ions from aqueous solution by dried biomass from Ficus religiosa

This research work presents the capability of Ficus religiosa as an eco-friendly biosorbent to remove heavy metals (lead and cadmium) from their aqueous solutions. The biomass from Ficus religiosa is available as waste in the form of dried branches. FTIR analysis indicated the presence of oxygen containing functional groups and a change in the vibrational frequencies indicated the attachment of Pb(II) and Cd(II) ions with these functional groups. Pseudo-second-order kinetic model was followed at all studied initial concentrations of metal ions. Langmuir and Dubinin-Radushkevich models were followed by Pb(II)-FR system and Langmuir model described the equilibrium of Cd(II) biosorption by FR. The maximum biosorption capacity of biosorbent for lead was 91.74 mg/g and for cadmium was 76.21 mg/g. The process was spontaneous, feasible and endothermic in nature. An increase in change in standard entropy indicated the establishment of equilibrium. It can be concluded from this research work that Ficus religiosa can be used as an alternative biosorbent for decontamination of lead and cadmium from aqueous solution due to feasible sorption conditions, low cost and biosorbent having good affinity for lead and cadmium ion.