Synthesis of poly(acrylamide-co-methyl methacrylate) chemicaly cross-linked hydrogels for efficient adsorption of red erionyl dye

Polyacrylamide (Poly (AAm)) and poly(acrylamide-co-methyl methacrylate) (poly (AAm-co-MMA)) hydrogels were synthesized by solution free radical polymerization initiated by Potassium persulfate initiator (KPS) at different feed mol monomer ratios and N,N-methylene bisacrylamide (BIS) as a crosslinking agent. The obtained hydrogels were characterized by FTIR, scanning electron microscopy (SEM) and swelling behaviour. The swelling properties of Poly (AAm) and poly (AAm-co-MMA) hydrogels were studied in distilled water at different pH. The effect of temperature on swelling behaviour of these hydrogels has been analysed by variation from 25 to 50?C. Poly(AAm-co-MMA) hydrogels were considered for the removal of Red Erionyl textile dyes from aqueous solutions. Two kinetics models were applied; the first and the second order kinetics as well as the Freundlich and Langmuir isotherms were tested. The result confirms that the adsorption process of Red Erionyl dye follows second-order kinetics and their equilibrium data were fitted well to the linear Langmuir model.