Predictive approach for simultaneous biosorption and bioaccumulation of arsenic by Corynebacterium glutamicum MTCC 2745 biofilm supported on NL/MnFe2O4 composite

The potential use of Corynebacterium glutamicum MTCC 2745 biofilm supported on NL/MnFe2O4 composite for eliminating both As(III) and As(V) from synthetic wastewater was inspected in a batch assay. Effects of operating parameters like pH, biosorbent dose, contact time, temperature and initial adsorbate concentration onto the removal efficiency was investigated. Minimum contact time to achieve equilibrium is 260 min at pH 7.0 at 30 °C temperature for both ions. Existence of functional groups onto the surface of biosorbent attached with biofilm that may interact with the As(III) and As(V) ions was proved by FT–IT, to estimate the applicability of this system for the elimination of those ions. To determine the most suitable correlation for the equilibrium curves employing the method of the nonlinear regression for curve fitting analysis, isotherm studies were carried out for As(III) and As(V) utilizing 30 isotherm models. The pattern of biosorption/bioaccumulation fitted well with Vieth and Sladek isotherm model for As(III) and Brouers–Sotolongo and Fritz–Schlunder-V isotherm models for As(V). D–R isotherm studies indicated that ion-exchange might play a prominent role. Desorption study was also performed with different concentrations of NaOH solution.