Kinetics Analysis of Crystal Violet Adsorption from Aqueous Solution onto Flamboyant Pod Biochar

Abstract

The increasing presence of presistent synthetic dyes, like crystal violet (CV), in wastewater poses a significant threat to aquatic ecosystems and human health due to its genotoxicity and carcinogenicity. Biochar derived from agricultural waste offers a promising, cost-effective, and eco-friendly approach for dye removal. This study explores the potential of flamboyant pod biochar (FPB) as a novel and sustainable adsorbent for CV removal. FPB offers a unique advantage as it utilizes readily available flamboyant pod waste, promoting waste valorization and a cost-effective approach. FPB was synthesized through a simple process involving milling, sun-drying, and pyrolyzing flamboyant pod waste at 300 °C. Batch adsorption experiments were conducted to evaluate the influence of contact time and initial dye concentration on removal efficiency. Kinetic modeling using pseudo-first-order and pseudo-second-order models explored the underlying mechanisms governing the adsorption process. The pseudo-second-order kinetic model exhibited a superior fit (R² > 0.87) compared to the pseudo-first-order model, suggesting a chemisorption mechanism governing the adsorption process. These findings demonstrate the potential of FPB as a low-cost, sustainable adsorbent for CV removal from wastewater.