Microporous activated carbon from Madhuca Longifolia flower for efficient methylene blue dye removal in wastewater treatment

This work focuses on developing microporous-activated carbon from the cost-effective Madhuca Longifolia flower using the potassium hydroxide activator at an activation temperature of 750 degrees C to remove methylene blue dye from an aqueous medium. The pore size, morphology, elemental composition, and specific surface area were analyzed using field emission scanning electron microscopy and the Brunauer-Emmett-Teller method. The prepared activated carbon showed a well-developed microstructure with a specific surface area of 764.68 m2/g. Fourier transform infrared spectroscopic study confirmed the alcoholic and carboxylic hydroxyl groups, which play a vital role in the adsorption kinetics. The pseudo-second-order kinetic model investigation revealed that chemical adsorption was the most important factor in this adsorption study. The Langmuir isotherm model fits this study's equilibrium data well and concludes that the Methylene Blue adsorption process might be a homogeneous monolayer adsorption. The developed activated carbon exhibited high absorptivity, with a maximum adsorption capacity of 168.54 mg/g for methylene blue dye in the aqueous medium. These findings confirmed that the sustainable and low-cost Madhuca Longifolia flower-derived activated carbon has a promising potential for removing pollutants such as methylene blue dye in drinking water.