Chemical Activation of Banana Peel Waste-Derived Biochar Using KOH and Urea for CO2 Capture

• Published in: Materials 2024-02, Vol.17 (4), p.872
• Main Authors: Sreńscek-Nazzal, Joanna, Kamińska, Adrianna, Serafin, Jarosław, Michalkiewicz, Beata
• Format: Article
• Language: English
• Subjects: Activated carbon; Adsorbents; Adsorption; Biomass; Carbon dioxide; Carbon sequestration; Carbonaceous materials; Decomposition; Emissions; Fruit juices; High temperature; Laboratories; Nitrogen; Raw materials; Sorbents; Temperature; Ureas
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17040872

This article describes the synthesis and characterization of porous carbon derived from waste banana peels by chemical activation with KOH or by activation KOH and urea modification. The as-synthesized samples were carefully characterized by various techniques. The prepared carbonaceous materials possess highly developed micropore and mesopore structures and high specific surface area (up to 2795 cm2/g for materials synthetized with KOH and 2718 cm2/g for activated carbons prepared with KOH and urea). A series of KOH-activated samples showed CO2 adsorption at 1 bar to 5.75 mmol/g at 0 °C and 3.74 mmol/g at 25 °C. The incorporation of nitrogen into the carbon sorbent structure increased the carbon uptake capacity of the resulting materials at 1 bar to 6.28 mmol/g and to 3.86 mmol/g at 0 °C and 25 °C, respectively. It was demonstrated that treatment with urea leads to a significant increase in nitrogen content and, consequently, CO2 adsorption, except for the material carbonized at 900 °C. At such a high temperature, almost complete decomposition of urea occurs. The results presented in this work could be used in the future for utilization of biomass such as banana peels as a low-cost adsorbent for CO2 capture, which could have a positive impact on the environment and human health protection.