Red mud-chitosan microspheres for removal of coexistent anions of environmental significance from water bodies

Aluminium industry waste red mud was combined with Chitosan so as to prepare novel composite in the form of beads. The Red mud–Chitosan beads (Rm-Ch) were studied for applicability in the removal of fluoride, chromate and phosphate ions from aqueous solution. The beads were characterized for surface morphology, elemental analysis, thermal stability and presence of functional groups. Thermodynamic, kinetics and isotherm studies carried for all the three anions revealed that the adsorption process is spontaneous, exothermic and follows pseudo second order kinetics in accordance with Langmuir adsorption isotherm. The adsorption capacities for these three ions were found to be 6.15 mg g-1, 30.88 mg g-1 and 23.54 mg g-1 respectively. [Display omitted]