Adsorption of Ag(I) on glycidyl methacrylate/N,N′-methylene bis-acrylamide chelating resins with embedded iron oxide

Glycidyl methacrylate/N,N′-methylene bis-acrylamide (GMA/MBA) resins modified by embedded iron oxide (Fe2O3) were prepared. Amino and thiol functionalities were immobilized on the obtained resins. The uptake of Ag(I) by the resins using batch and column techniques was investigated. The oxide-containing resins showed higher uptake values relative to the corresponding oxide-free ones. The uptake of Ag(I) on the resins was found to follow pseudo second-order kinetics. The uptake process was investigated at different temperatures and ΔH°, ΔS° and ΔG° were calculated. Regeneration of the resins was achieved using thiourea, HNO3 and acidified thiourea with HNO3. Regeneration efficiency was found to be 98% over five cycles with no appreciable change in durability.