Characterization and kinetic analysis of leaves and stems of Lippia origanoides bagasse: exploring its potential as solid fuel

Biomass is one of the most promising renewable energy sources due to its worldwide availability, the possibility of producing heat and power on demand, and its potential CO₂ neutrality. However, there is a lack of characterization of residual biomasses from agro-industrial processes. This study presents a comprehensive characterization and kinetic modeling of Lippia origanoides bagasse, a residual biomass from essential oil extraction. The proximate analysis revealed moisture contents of 9.47% (leaves), 9.26% (stems), and 9.89% (mixture), with volatile matter reaching up to 75.67% in stems and ash content as low as 5.50%, indicating favorable combustion properties. The estimated higher heating value (HHV) of the stem fraction was 18.65 MJ/kg, which is 6.7% higher than the leaves fraction and 1.9% higher than the mixture. Elemental composition showed carbon contents of 46.43% (stems), 43.77% (leaves), and 45.64% (mixture), supporting its energy potential. Kinetic parameters were determined using the independent parallel reaction scheme (IPRS), with activation energies ranging from 61.3 to 256.7 kJ/mol depending on the biomass type and atmosphere. This approach represents a significant advancement over previous single-step kinetic models applied to this biomass. Modeled decomposition curves showed excellent agreement with experimental data (%Fit < 5%). These findings highlight the potential of Lippia origanoides bagasse—particularly its stem fraction—as a viable solid fuel and provide ro bust parameters for simulating its thermal behavior.