Composites of cellulose nanofibers and silver nanoparticles for malachite green dye removal from water

Abstract

The development of eco-friendly materials to remove toxic chemicals from water is highly sought after in the present days. In the current study, the composites of cellulose nanofiber (CNF) and silver nanoparticles (Ag NPs) were prepared and their ability to adsorb malachite green (MG) dye under different conditions was investigated. XRD, FTIR, EDX analyses of samples confirmed the presence of Ag NPs on the CNFs and the sorption of MG dye on composites. The effects of various parameters (such as contact time, CNFs - Ag NPs dose, initial MG concentration, pH, and temperature) on MG degradation were evaluated. The maximum removal was obtained at a pH of 8 and temperature of 303 K. The adsorption equilibrium was described well by the Freundlich isotherm model suggesting multilayer physical adsorption. The maximum uptake of MG dye using CNF-Ag NPs composites was found to be 142 mg/g, which is superior to the silver-based composites reported in the literature. Adsorption kinetics were predicted by the pseudo-first-order kinetic model rather than the pseudo-second-order kinetic model. This method is promising due to its cost-effective nature as well as the use of bio-based materials.

Keywords

• Silver nanoparticles
• Cellulose nanofibers
• Malachite green
• Dye removal
• Composites