The ternary blends consisting of biodegradable polymer-based ternary blends composites were prepared by the solution blending method with glutaraldehyde. Prepared ternary blends were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. Subsequently, the adsorbent activity for heavy metal, chromium, was estimated in terms of the existent initial concentration, adsorbent dose, contact time, and pH. The adsorption study was performed for the pH ranging from pH 4.0 to 8.0. It was observed that the sorption efficiency, increased with increasing the pH of the solution from 4.0 to 5.5. At low pH values of the solution, the amine groups were propagated to various degrees, reducing the number of binding sites available for metal ion uptake so that the extent of chromium uptake is low in the high concentrations of protons. Moreover, the protonation of amine groups is induced an electrostatic repulsion of cations. When the pH of the solution was more than 5.5, the sorption rate began to decrease. Besides, the quantity of adsorbate on absorbent was fitted as a function in Langmuir and Freundlich isotherm. The sorption kinetics were tested for pseudo first- and pseudo second-order reactions. The kinetic experimental data correlated with the second-order kinetic model and rate constants of sorption for kinetic models were calculated and accordingly, the correlation coefficients were obtained. The investigation emphasized that the composite was very effective for the adsorption of Cr (VI).
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