Synthesis, characterization and thermo-kinetic analysis of sawdust biochar for adsorbent and combustion drives

Biochar is synthesized using two wood species as Dalbergia sissoo wood (DSW) and Mangifera indica wood (MIW), employing pyrolysis of sawdust on a lab-scale. Chemical analysis of these biochars is carried out using elemental analyzer, BET, FTIR, FE-SEM-EDX, and TGA-DTG-DTA analyses. Results showed that high surface area (87.12 and 88.04 m²/g), pore volume (0.0439 and 0.0443 cm³/g), and gross calorific value (28.19 and 28.00 MJ/kg) of DSW and MIW biochar indicate their suitability as sorbent and energy source. Thermogravimetric modeling, based on Coats-Redfern method, is applied on combustion data of biochar samples obtained at 10 and 20 °C/min. Activation energy of DSW- and MIW-biochar are estimated as 2.61–80.49 kJ/mol and 2.58–77.90 kJ/mol, respectively. Statistical analysis of results (R² > 0.90) indicated the adequacy of proposed kinetic modeling in reproducing the experimental combustion behavior. The propitious outcome of this study account for favoring sawdust-biochar as a good adsorbent and combustion feedstock.