Activated biocarbons derived from molasses as new tailored CO2 adsorbents

Karolina Kiełbasa

doi:10.3389/fchem.2023.1184389

Activated biocarbons derived from molasses as new tailored CO₂ adsorbents

Front Chem. 2023 Jun 19:11:1184389. doi: 10.3389/fchem.2023.1184389. eCollection 2023.

Author

Karolina Kiełbasa¹

Affiliation

¹ Department of Catalytic and Sorbent Materials Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Szczecin, Poland.

Abstract

An innovative and cost-effective method for enhancing CO₂ capture by modifying the textural properties of derived activated biocarbons was explored. A molasses solution was prepared with a sucrose concentration of 1 mol/dm³. A two-step synthesis process was involved, which includes the hydrothermal synthesis of spherical carbonaceous materials from molasses followed by chemical activation. The carbonaceous material to activation agent ratio was studied from 1 to 4. The CO₂ adsorption of all activated biocarbons was tested at 0, 10, and 20°C and a pressure of up to 1 bar. The results showed a significant correlation between CO₂ adsorption and the textural properties of the activated biocarbons. The activated biocarbon with the highest CO₂ adsorption of 7.1 mmol/g at 1 bar and 0°C was successfully produced by modifying with KOH. The selectivity of CO₂ over N₂ calculated on the basis of the Ideal Adsorbed Solution Theory was excellent (16.5). The Sips model was found to be the most suitable, and the isosteric heats of adsorption were also specified.

Keywords: CO2 adsorption; CO2/N2 selectivity; activated biocarbon; adsorption models; molasses.