Adsorption of azo dyes by a novel bio-nanocomposite based on whey protein nanofibrils and nano-clay: Equilibrium isotherm and kinetic modeling

Excessive discharge of synthetic azo dyes into the aquatic ecosystem is a global concern. Here, we develop green approach to remediate dye pollutants by fabricating an easily separable bio-nanocomposite, based on nanofibrils from whey protein concentrate together with montmorillonite. The nanocomposite was characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and surface area analysis. Nanofibrils lead uniform dispersion montmorillonite in matrix also reinforce nanocomposite. adsorption efficacy monitored cationic (Chrysoidine-G, Bismarck brown-R), reactive (reactive black-5, orange-16), acidic (acid red-88, acid red-114) direct (direct violet-51, Congo red) dyes. adsorbed different kinetics, quicker slower. Greater than 93% Chrysoidine-G over wide range concentration pH. Acidic pH higher temperature are more favorable for process. Equilibrium data were reasonably fitted linear (Nernst) isotherm model indicating existence unlimited number sites which consistent high experimental uptake 731 mg/g. Kinetic well-described pseudo-second-order intra-particle diffusion models. We conclude that this environmentally friendly has good potential use wastewater treatment related purposes.