Removal of Reactive Yellow Dye from Aqueous Solutions Using Hydrogel Nanocomposites Based on Montmorillonite Clay

This study investigates the efficacy of hydrogel nanocomposites as adsorbents for the removal of reactive yellow (RY) dye from aqueous solutions. Sodium montmorillonite (MMT) nanofillers were incorporated into poly N-isopropylacrylamide (poly (NIPAM)) and polyacrylic acid (poly (AAC)) hydrogels to create the nanocomposites. XRD, TGA, FTIR, and SEM techniques were used to characterize the resulting materials. The effects of several parameters on the adsorption process were comprehensively examined, including nanocomposite dose, solution pH, contact time, and initial dye concentration. The results showed that an acidic environment (pH 7), with a contact time of 90 minutes and a dosage of 0.05 g of the nanocomposite, was optimal for achieving maximum adsorption capacity of RY dye. Poly (AAC) nanocomposites, poly (NIPAM) nanocomposites, and poly (NIPAM-co-AAC) nanocomposites showed the highest adsorption capacities of 168.3, 108.22, and 128.9 mg/g, respectively. The Langmuir and Freundlich isotherm models were used to fit the experimental data, with the Freundlich model demonstrating a superior fit. Kinetic studies further indicated that the dye adsorption process adhered to the pseudo-second-order kinetic model.