Abstract
In the present study, chitosan-N-vinyl imidazole was first synthesized and characterized and then its capacity for removal of mercury (II) ions from water was assessed. The graft copolymerization of N-vinyl imidazole onto chitosan chains has been developed in aqueous medium using microwave irradiation. The obtained copolymer was characterized by Fourier Transform Infrared (ATR-FTIR), solid-state Citation13C Nuclear Magnetic Resonance (NMR), Differential Scanning Calorimetric (DSC) and Thermogravimetric Analysis (TGA). Mercury (II) ions removal capacity by the chitosan-N-vinyl imidazole were investigated in aqueous solutions using different amounts of these ions at pH = 6.0. The effect of the contact time, kinetics and thermodynamic studies on the adsorption of mercury ions was also reported. The maximum adsorption capacity was found to be 112.35 mg g−1 from the Langmuir isotherm model at 25 °C. The obtained negative value of (kJ mol−1) and (kJ mol−1) indicated the spontaneous and endothermic nature of the reactions. The regeneration of CS-N-vinyl imidazole was investigated using PEG-400 in water as desorbing agent. This data make chitosan-N-vinyl imidazole a potential material adsorbent for mercury (II) removal.
Synthesize of CS-N-vinyl imidazole is done under microwave irradiation.
Removal of mercury in aqueous solution was performed in batch studies.
Mercury adsorption has been simulated using Langmuir and Freundlich models.
Thermodynamic properties of the adsorption process have been determined.
Regeneration has been studied using PEG-400 as desorbing agent.