Eucalyptus (camaldulensis) bark-based composites for efficient Basic Blue 41 dye biosorption from aqueous stream: Kinetics, isothermal, and thermodynamic studies

Abstract

For the recycling of polluted water bodies to protect and maintain the eco-friendly future environment herein for the first time Eucalyptus Bark (EB) and its composites were designed to eliminate the dye Basic Blue 41 (BB41) from an aqueous medium. Physicochemical properties of as-fabricated native EB and their composites were analytically determined. From the batch adsorption experiments, the optimum recorded adsorption factors by as-designed adsorbents were pH: 8 for EB, 7 for MG/EB, and 10 for Ppy/EB, adsorbent dosage: 0.05 g/L, agitation speed: 120 rpm, contact time: 90 min, particle size of adsorbent: ≤ 300 μm, initial concentration: 200 mg/L, and temperature: 300 K. Under optimized conditions, as-prepared adsorbents exhibited high BB41 dye adsorption capacity and decolorization efficiency (186.7 mg/g and 93.0%) due to existence of negatively charged functional groups on the adsorbent surface because of its cellulosic nature. Isothermal and kinetic studies revealed that BB41 adsorption experimental data were best fitted by Freundlich and pseudo 2nd order models. From thermodynamic examination, the adsorption process is spontaneous, chemisorption, and exothermic in nature. Furthermore, the influence of salts and surfactants on dye adsorption capabilities by adsorbents has also been determined. From desorption experiments, it was concluded that low concentration of eluting agents is responsible for high amounts of dye desorption. This study revealed that the magnetic and polypyrrole composites with EB biomass have promising adsorption potential and this class of adsorbent could be used for the eco-friendly remediation of wastewater containing BB41 dye.