Performance of activated carbons synthesized from fruit dehydration biowastes for supercapacitor applications

Abstract

This research documents variability in electrode performance of activated carbons (ACs) produced from two different commercial fruit dehydration wastes through hydrothermal carbonization and chemical activation pathway. Commercial spent osmotic solutions (SOSs) from blueberry dehydration (BSOS) and glycerated cherry dehydration (CSOS) waste materials were subjected to hydrothermal carbonization at 250°C under nitrogen conditions for 30 min to extract hydrochars. BSOS‐ and CSOS‐derived hydrochar powders were further activated using phosphoric acid at 900°C to produce ACs. Results showed that the two commercial fruit dehydration wastes resulted in ACs with different pore characteristics, where the AC‐CSOS showed a higher level diversity in mesoporosity in addition higher surface area once compared to AC‐BSOS. The produced ACs were utilized in a symmetrical electrical double layer supercapacitor (EDLCs) to measure their performance as an electrode. The EDLCs fabricated from AC‐CSOS delivered a higher level of performance, where these materials showed up to 48 F/g specific capacity. Overall, the AC electrodes derived from the SOSs were comparable to many bio‐derived electrodes used for EDLCs, but subsequent enhancement to surface chemistry and surface area is required to outperform some of the best ACs and engineered carbon materials in this application. © 2018 American Institute of Chemical Engineers Environ Prog, 38:e13030, 2019