Green fabrication and efficiency of activated biochar-layered double hydroxide (LDH) nanocomposites against toxic Pink-XFG dye

Removal of dyes has been a matter of great interest for researchers because of health and toxicity issues. In this research work, green biochar was produced using precipitation technique, and by the adsorption process, it was supported on layered double hydroxide (LDH). Biochar/LDH composites were synthesized from Neem, Amaltas, and Keekar stems, eggshells, and Eucalyptus (N, A, K, Egg, and Eu's biochar/LDH-composite). These composites were employed to remove synthetic dyes from an aqueous solution. Recent studies have identified optimal conditions for LDH-composites under various parameters: pH 9 or 10 with a dosage of 0.05 g/50 mL yields higher adsorption capacities across different LDH composites, ranging from 40.74 to 48.30 mg/g at a reaction time of 90 min using a Pink-XFG dye concentration of 10 ppm, which is favorable. Temperatures of 303–308 K are suitable. Second-order kinetics, along with the Langmuir and Freundlich adsorption isotherms, along with exothermic reactions, presented good-fit results on adsorption kinetics and equilibrium data. The adsorption potential was significantly affected by various concentrations of electrolytes, surfactants, detergents, and heavy metal ions. 0.5 N hydrochloric acid was determined to be the most efficient agent for the process of desorption. These methods are very cost-effective, eco-friendly, and easy to manufacture.