Determination of the Pyrolytic Characteristics of Various Biomass Pellets

Abstract

Biomass pellets are widely used for combustion but can also serve as sustainable feedstocks for pyrolysis. This study examined wood (WP), palm-pruning (PP), reed (RD), and daphne (DP) pellets. We present a compact framework linking composition (proximate/ultimate and lignocellulosic fractions) with TG/DTG, FTIR, TGA-derived indices (CPI, Ddev, Rw), Tpmax and Rav to predict product selectivity and temperature ranges. TG/DTG showed the following sequence: hemicellulose (≈200–315 °C) first, cellulose (≈315–400 °C) with a sharp maximum, and lignin ≈200–600 °C. Low-ash WP and DP had sharper, higher peaks, favoring concentrated devolatilization and condensables. Mineral-rich PP and RD began earlier and showed depressed peaks from AAEM catalysis, shifting toward gases and ash-richer chars. Composition shaped these patterns: higher cellulose increased Rav and CPI; links to Tpmax were moderated by ash. Lignin strengthened a high-T shoulder, while hemicellulose promoted early deacetylation (RD’s 1730 cm−1 acetyl C=O) and release of CO2 and acids. Correlations (|r| ≥ 0.70) supported these links: VM with total (m∞) and second stage mass loss; cellulose with Rav and CPI (Tpmax moderated by ash); lignin and O/C with Tf and last stage mass loss; ash negatively with Ti, Tpmax, and m∞. The obtained results guide the sustainable valorization of biomass pellets by selecting temperatures for liquids, H2/CO-rich gases or low-ash aromatic chars.