Mango stone biocomposite preparation and application for crystal violet adsorption: A mechanistic study

Abstract Mango stone biocomposite (MSBC) was prepared and employed for the adsorption of crystal violet (CV) dye. Process variables were optimized and maximum dye adsorption of 352.79 mg/g was achieved at pH 8, 0.05 g adsorbent dose, 30 min contact time, 33 °C for dye initial concentration of 400 mg/L. Salt and surfactants pre-treatments of MSBC did not affect the CV adsorption. The CV equilibrium adsorption data followed pseudo second order kinetic model and Langmuir adsorption isotherm. Thermodynamic parameters (ΔG°, ΔH° and ΔS°) revealed that the CV adsorption onto MSBC was an exothermic and spontaneous process. SEM analysis revealed that the surface morphology of dye loaded MSBC was changed significantly and hydroxyl and carbonyl groups were main functional group responsible for CV adsorption onto MSBC. The prepared MSBC also showed recyclable nature and might be potential candidate for dyes removal form textile effluents.