Self-nitrogen doped carbons aerogel derived from waste cigarette butts (cellulose acetate) for the adsorption of BPA: Kinetics and adsorption mechanisms

Abstract

The fabrication of highly porous functionalized carbon materials is the demand of current scenario for the removal of toxic pollutants form aqueous solution. Therefore, waste cigarette butts that consist of cellulose acetate and other nitrogen rich compounds, such as nicotine and harmine have been used for the fabrication of N-doped carbon aerogel (NDC) via hydrothermal and carbonization process. As-fabricated NDC was characterized via, elemental analysis, FTIR, Raman, TGA, XRD, BET, SEM and XPS and used for the adsorption of bisphenol –A (BPA). The outcomes of adsorption essay and its kinetics support that the adsorption of BPA over NDC was carried out via pseudo-second-order kinetic model and via Langmuir model isotherm. The values for ΔG and ΔH were found negative and positive respectively, and support that the adsorption process is spontaneous and endothermic. The nature of adsorbent as well as in-situ and post characterization of the adsorbent support the adsorption mechanism, and the conclusions support that the hydrogen bonding, electrostatic as well as the π-π interactions were employed between the BPA and NDC during adsorption. In addition, the regeneration of the NDC was efficiently achieved and BPA removal efficiency remained high (92.47%) after seven cycles.

Keywords

• Cellulose acetate
• Nicotine
• Nanocomposite
• FTIR
• Bisphenol-A
• N-doped carbon