EFFECT OF PYROLYSIS TEMPERATURE ON THE STRUCTURE, TEXTURE AND THERMAL STABILITY OF MAIZE COB BIOCHAR

Journal: Acta Chemica Malaysia (ACMY)
Author: V.O. Idode, J.M. Okuo, F.E. Okieimen
ISSN: 2576-6732
e-ISSN: 2576-6724

This is an open access journal distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: 10.26480/acmy.02.2025.131.134

The aim of this study was to investigate the effect of pyrolysis temperature on the structural, textural, and thermal stability characteristics of maize cob biochar. Biochar was produced by pyrolysis of maize cobs at different temperature (250°C, 300°C, and 350°C), and the resulting biochars were characterized using scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) surface analysis, X-ray fluorescence spectroscopy (XRS-FP), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR). Results showed that increasing pyrolysis temperature led to the development of more pronounced pore structures and increased BET surface area (251.0–325.4 m²/g), with the highest micropore surface area observed at 300°C. Elemental analysis revealed a decrease in nutrient and mineral content with increasing temperature. TGA indicated improved thermal stability at higher temperatures, particularly for the 350°C biochar. FTIR spectra demonstrated a decline in labile functional groups and increased aromaticity with temperature. The findings suggest that maize cob biochars produced at lower temperatures retain more functional groups and mineral elements beneficial for soil amendment, while those produced at higher temperatures exhibit greater thermal stability and aromaticity, making them suitable for long-term carbon sequestration and soil remediation applications.