The effective removal of toxic pollutants from water and waste water, is a challenging issue for environmental protection. In the present work, the performance of Artocarpus Heterophyllus (jackfruit) leaves have been examined for reduction of toxic Cr (VI) and Cd (II) from synthetic wastewater. Characterization of the adsorbent was made to evaluate the surface morphology and chemical composition, by Scanning Electron Micrograph (SEM) and Energy Dispersive Spectroscopy (EDS). Characteristic surface groups [Fourier Transform Infra-Red (FTIR)], surface area and surface structure [Brunauer–Emmett–Teller, (BET)] were also determined. The influences of various factors which control the removal process were studied experimentally in batch method and optimized. High removal efficiency was obtained at pH ≤ 2 for Cr (VI); and for Cd (II) it was ≥ 6. The experimental data were tested using different kinetic and isotherm models. Artocarpus Heterophyllus leaf was found suitable to remove 99.7 % Cr (VI) and 98.4 % Cd (II) from a strength of 20 mg L-1 solution at 0.5 g L-1 adsorbent concentration, at their respective favorable pHs. The reaction followed pseudo second order kinetic model for both the cases. The calculated sorption energy of 16.16 and 12.68 kJ mol-1, suggested chemical nature for both the cases. Desorption studies showed the effective reuse of Artocarpus Heterophyllus leaf for three times. The relatively high equilibrium adsorption capacity of 32.29 and 20.37 mg g-1 for Cr (VI) and Cd (II) respectively, suggested use of Artocarpus Heterophyllus leaf as a reasonably good green bio-adsorbent. The modeling of the complex adsorption process based on artificial neural network approach exhibited reliability and high degree of proficiency (R values of 0.999) in the model’s prediction and experimental data indicated its applicability in forecasting removal efficiency for both the metal ions.
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