ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

CO₂ adsorption by KOH-activated hydrochar derived from banana peel waste

Chirag Goel, Sooraj Mohan, P. Dinesha, and Marc A. Rosen

Department of Mechanical and Industrial Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, India

E-mail: dinesha.p@manipal.edu

Received: 19 May 2023  Accepted: 31 January 2024

Abstract:

Hydrothermal carbonization is one of the effective methods of converting wet lignocellulosic biomass into carbon-rich hydrochar. Due to its characteristic application on CO₂ capture and storage, many researchers have studied the CO₂ uptake on activated hydrochar. The present work studies the CO₂ uptake from banana-peel-derived activated hydrochar which is not presented in the literature. Hydrochar is obtained at three different temperatures (180, 200, and 220 °C) and activated using KOH. Characterization studies including SEM, XRD and FTIR were performed to examine the structure and chemistry of the derived activated hydrochar. The hydrochar sample (BP-180) when activated with a KOH/hydrochar ratio of 3 and an activation temperature of 700 °C has a well-developed microstructure with a surface area and pore volume of 243.4 m²/g and 0.0931 cm³/g, respectively. Samples obtained at higher process temperatures (BP-200 and BP-220) showed much lower porosity. Similarly, the maximum CO₂ adsorption is recorded for BP-180 (3.8 mmol/g), followed by BP-200 and BP-220 with maximum adsorption capacities of 3.71 and 3.18 mmol/g, respectively, at 1 bar and 25 °C.

Keywords: Activated carbon; CO2 adsorption; Banana peel waste; Hydrochar; Climate change

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03355-z

Chemical Papers 78 (6) 3845–3856 (2024)