Nickel-Cadmium (Ni-Cd) rechargeable batteries are widely used as portable power source in many electronic devices. Once obsolete, disposable of these batteries in an environmental concern due to the presence of heavy metals nickel and cadmium (Cd).1Pollution by heavy metals is a serious environmental health concern, as most of them are non-biodegradable, have low permissible limit as well as toxic to the living beings. The sustainable solution to this problem is the adoption of novel cleaner technologies to recover and recycle heavy metals.2, 3 The above strategy was applied to recover Cd from Ni-Cd battery waste by employing Acrylamide grafted chitosan based ion imprinted polymers (CdIIP). CdIIP was synthesised using Cd (template), Acrylamide grafted chitosan (polymer) and Epichlorohydrin (EPI) as the crosslinker. Chitosan is a cheap biosorbent, extensively used for recovery of heavy metals. Grafting the chitosan helps to improve its efficiency. 2, 4, Computational studies were performed to select suitable grafting agent as well as appropriate crosslinker. The Gibbs free energy revealed Acrylamide to be the best grafting agent (∆G -17.98Kcal/mol). Amongst the crosslinking agent, (EPI) (∆G -723.08Kcal/mol) was found to be better than Glutaraldehyde (∆G-107.31Kcal/mol) which was also confirmed by EDS results. FT-IR, SEM and EDS confirmed the successful preparation of CdIIP. The molecular recognition abilities were described by Langmuir adsorption model. The kinetic data fitted into pseudo second order equation. CdIIP and control polymer (NIP), depicted the adsorption capacity (BIIP) 238 ± 25 mg/g and (BNIP) 71 ± 6 mg/g respectively. CdIIP could efficiently recovery 84.3% of Cd from the leached Ni-Cd battery waste.
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