ABSTRACT
In this investigation, we synthesize and characterize zirconium (Zr) and Zr-Fe coated biosolid biochar (BSBC) to determine the sorption capacity of arsenate, As(V). The combined results of specific surface area (BET-N2), FTIR, XRD, SEM, and TEM confirmed that Zr(IV) and Zr-Fe were successfully coated onto BSBC. The effects of reaction time, pH, initial As(V) concentration, adsorbate doses, temperature, ionic strength, at different concentrations on the adsorption of As(V) were investigated. At equilibrium, the experimental sorption data were successfully modelled using Langmuir (R2 = 0.98) and Freundlich (R2 = 0.99) isotherms where Freundlich model fitted well. Kinetic data were fitted with pseudo first order and second order model where best fitted with second order kinetics (R2 = 0.99). The maximum sorption capacity of Zr-BSBC and Zr-FeBSBC composites were 18.97 and 27.73 mg/g, respectively at pH 6. The thermodynamic parameters (viz. changes in Gibbs free energy, enthalpy, and entropy) suggested that the adsorption process is spontaneously endothermic and feasible in nature. The results suggest that Zr-O and Zr-O-Fe coated BSBC could serve as promising adsorbents for remediating As(V) contaminated water.
