Valorization of Terminalia catappa Fruit Waste into Activated Carbon through KOH-Assisted Pyrolysis
Iwan Nugraha Gusniar, Agus Sutanto, Gunawarman, Nidya Chitraningrum, Eri Widianto, Alifah Naira Soraya, Rizal Hanifi, Kardiman, Siswadi

a Department of Mechanical Engineering, Faculty of Engineering, Universitas Andalas, Limau Manis, Padang, West Sumatera, 25166, Indonesia.
b Department of Mechanical Engineering, Faculty of Engineering, Universitas Singaperbangsa Karawang, Telukjambe Timur, Karawang 41361, Indonesia.
c Research Center for Biomass and Bioproduct, National Research and Innovation Agency (BRIN), KST Soekarno, Cibinong, 16911, Indonesia.
d Department of Physics, Faculty of Engineering, Universitas Singaperbangsa Karawang, Telukjambe Timur, Karawang 41361, Indonesia.

Abstract

Biomass derived carbon materials are increasingly considered as sustainable alternatives to conventional adsorbents due to their availability and low cost. In this work, Terminalia catappa fruit waste was utilized as a precursor to produce activated carbon via KOH assisted pyrolysis at 400 C and 800 C. Raman spectra show the characteristic D (1348 cm) and G (1595 cm) bands, representing disordered and graphitic carbon structures, respectively. The higher-temperature sample exhibits a more pronounced G band, indicating improved structural ordering, although defect related features remain evident. FTIR analysis reveals the presence of oxygen containing functional groups, including OH, CO, and C same C stretching associated with aromatic structures, with reduced intensity observed at higher temperature, suggesting enhanced carbon stabilization. Morphological observations confirm that higher pyrolysis temperature promotes more developed and interconnected pore structures. Elemental analysis further indicates that carbon is the dominant component, confirming effective biomass conversion. These results demonstrate that Terminalia catappa fruit waste can be converted into porous activated carbon through a simple and efficient process, with potential applications in environmental remediation, energy related fields, and microwave absorption materials.

Keywords: Activated carbon, Terminalia catappa, KOH activation, pyrolysis, biomass valorization

Topic: Material Physics