Nanocomposite hydrogel based on Sodium Alginate and MnO 2 : A Simple Strategy for Catalytic Degradation of Organic Dye

In the present work, degradation of crystal violet (CV) was studied using a heterogeneous Fenton-like system in aqueous solution A mesoporous nanocomposite hydrogel was synthesized based on sodium alginate biopolymer and AMPS/AAm monomers through radical polymerization followed by incorporation of manganese oxide nanoparticles within the hydrogel. The structure, and morphology of the nanocomposite hydrogel (MnO ₂ /NCH) were analyzed using the Brunauer-Emmett-Teller (BET), Field emission scanning electron microscope (FESEM), energy dispersive X-ray analysis, (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Zeta Potential, and Dynamic Light Scattering (DLS). The effect of different parameters such as initial pH of solution, amount of the loaded metal ion, time, temperature, dose of H ₂ O ₂ , dose of catalyst, and dye concentration on dye removal was studied. The degradation ratio in optimal conditions was over 98% in a relatively short time (20 min). The high reusability was obtained for the catalyst in consecutive cycles. The degradation studies indicate that the catalytic reaction follows the pseudo zero-order kinetic model.