Effect of barium activation on chitosan derived carbon: enhancement of CO₂ adsorption capacity

ABSTRACT

Spherical carbon was synthesised from chitosan, which was impregnated with different compositions of barium by ‘wet impregnation method’ and subsequently activated by thermal treatment. The as-prepared carbon and barium-activated carbons were characterised for their textural, thermal properties and elemental composition using SEM, EDS, CHN analyser, TGA, FT-IR, XRD and BET surface area analyser. The surface area of the unimpregnated carbon was found to be around 20 m²/g, whereas that of carbon impregnated with 10, 20 and 30 wt% barium was found to be 259.01, 106.60, and 99.21 m²/g, respectively. The TGA results showed that the barium-loaded carbons have higher thermal stability (beyond 500^°C) as compared to the unloaded carbon. Moreover, the 10 wt% barium-loaded carbon exhibited a CO₂ adsorption capacity of 86.23 mg/g at ambient temperature with excellent regeneration, which was higher in comparison with the unimpregnated carbon that possessed 60.00 mg/g. Being CO₂ a weak Lewis acid molecule, the barium-activated carbon, which is a weak base, could positively influence its CO₂ adsorption capacity.

KEYWORDS:

• Chitosan
• activated carbon
• barium
• CO₂ adsorption

Acknowledgements

The authors are grateful to the Director, DEBEL, Bangalore, for providing experimental facilities. The authors would also like to thank Dr R. Ramani for conducting the TGA analysis and Bangalore Institute of Technology, Bangalore, for BET surface area analysis. One of the authors, MK, thankfully acknowledges a research fellowship from DRDO, the Government of India.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.