Removal of crystal violet from aqueous solution by sorption into semi-interpenetrated networks hydrogels constituted of poly(acrylic acid-acrylamide-methacrylate) and amylose.

The dynamic remove of Crystal Violet (CV) by Semi-IPN hydrogels constituted of poly(acrylic acid-acrylamide-methacrylate) and amylose was studied. Adsorption capacity, kinetic and isotherm studies of CV onto hydrogels have been evaluated. It was found that the sorption process agreed very well with the Langmuir model and the adsorption of CV depended on the length of the side chain, amylose content and pH of the solution. For three types of hydrogels, n1-1, n2-1 and n4-1, the equilibrated amounts of CV adsorbed on the hydrogels decreased in the following order: n4-1 (28.6 mg/g)>n2-1 (25.0 mg/g)>n1-1 (20.0mg/g). Increasing the amylose content led to decrease the equilibrated amounts of CV adsorbed on the hydrogels. Moreover, adsorption kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model, indicating that the chemical adsorption was the rate-limiting step. Copyright 2009 Elsevier Ltd. All rights reserved.