Research on Dye Adsorption Behavior of Tobacco Carbon-based Adsorbent

In order to address the demands of dye wastewater treatment, high-efficiency adsorption materials were prepared from tobacco waste in this study. The tobacco-based carbon absorbent was prepared via a simple carbonization and pore-forming strategy with tobacco waste as the precursor. The physicochemical properties and adsorption behavior of the materials were characterized using instruments such as UV-Vis spectrophotometer, Fourier transform infrared spectroscopy, and scanning electron microscopy. The results indicate that the KOH- activated adsorbent (AC@KOH) possesses a uniform microporous structure (2.8614 nm) and a high specific surface area (1125.351 m²/g) which is 210 times higher than original unmodified biochar (AC). The adsorption capacity of AC@KOH for methylene blue and rhodamine B reaches 640.75 mg/g and 639.45 mg/g, respectively. The adsorption process is accorded with the pseudo-second-order kinetic model, predominantly involving chemical adsorption. The adsorption behavior of AC@KOH is governed by a synergistic effect of multiple interactions, including coordination, hydrogen bonding, ion-π or π-π interactions, electrostatic interactions, and physical pore confinement effects. This study successfully develops a high-performance tobacco-based carbon adsorbent, providing theoretical references and design insights for low-cost, practical green treatment of dye wastewater.