Eco-Engineered Polyaniline-Fe₃O₄@Biochar Hybrid from Delonix regia Seeds for Dye Wastewater Purification

The current report examined the potential of polyaniline modified Fe ₃ O ₄ -Delonix regia seed biochar nanocomposite to adsorb congo red from synthetic wastewater. In this study, biochar was synthesized through carbonization process at a peak temperature of 500°C. Fe ₃ O ₄ nanoparticles were synthesized using aqueous extract of Delonix regia seed pod. The consequence of pH, concentration and stirring speed on removal of congo red is examined. A maximum removal efficiency of 91.63% was obtained at optimal conditions of pH − 8, initial CR concentration – 50 mg/L and agitation speed − 500 rpm. The adsorption result demonstrated that experimental consequences fit well with Langmuir adsorption isotherm and pseudo second order kinetics was followed. A maximum sorption ability of 384.615 mg/g was obtained. Thermodynamic results shown that the sorption is spontaneous, reversible and endothermic one. The adsorption mechanism was explored and electrostatic attraction is the major rate controlling one. The current study established the efficiency of polyaniline modified Fe ₃ O ₄ -Delonix regia seed biochar nanocomposite as an sorbent in removal of congo red. The solid agro waste is effectively transformed and applied in industrial wastewater treatment.