Carboxymethyl cellulose embedded silica membrane impregnated with ZVI NPs for the catalytic detoxification of methyl orange dye and its kinetic and optimization studies.

Polymer composites, carboxymethyl cellulose (CMC) and silica-coated carboxymethyl cellulose (CMCSi) were used as supports for zero-valent iron nanoparticles (Fe0 NPs), yielding dip-catalysts represented as CMC@Fe0 and CMCSi@Fe0. The catalysts were created through the adsorption of Fe3+ ions on the polymer matrices, with the subsequent chemical reduction with NaBH4 in aqueous solution. Using FTIR, XRD, and FESEM, structural and morphological topographies were characterized. The composite's catalytic efficiency was evaluated through the degradation of methyl orange (MO) dye. CMCSi@Fe0 and CMC@Fe0 achieved 89.4 % and 85.0 % degradation in 8 and 13 min. Kinetic modeling disclosed that CMCSi@Fe0 followed pseudo-first-order kinetics (R2 = 0.921, kapp = 4.44 min-1), where CMC@Fe0 best fitted a zero-order (R2 = 0.917). The impact of reaction parameters, including temperature, NaBH4 concentration, MO concentration, and pH, was thoroughly explored. At elevated temperature, acidic pH, and higher NaBH4 dosage, optimal degradation occurred. These findings validate that CMC@Fe0 and CMCSi@Fe0 membranes not only act as effective catalysts for dye detoxification but also hold the potential for water filtration and functional group transformation applications.