The effect of pyrolysis conditions on char reactivity has been studied using Raman spectroscopy. Thispaper reports on the relationship between the properties of biomass char and the gasification rate. The gasificationkinetics of biomass char have been revealed by measuring the rate of weight loss during its reactionwith CO2 as a function of temperature. First-order kinetic rate constants are determined by fitting theweight loss data using a random pore model. The relationship between the char structure and CO2 gasificationreactivity was investigated in the range of 15–600 °C/min at a constant pyrolysis pressure (0.1 Mpa),and 0.1–3.0 Mpa at a constant heating rate (15 °C/min). The experimental results reveal that the reactivityof biomass char is determined by the pyrolysis condition. The CO2 gasification rates in char generated at0.1 Mpa exhibited approximately twice the values as compared to those obtained at 3 Mpa. This is becausethe uniformity of the carbonaceous structure increases with the pyrolysis pressure. The uniformity of carbonaceousstructures would affect the CO2 gasification reactivity, and the decreasing uniformity would leadto the progression of cavities on the char surface during the CO2 gasification process. The gasification rateof biomass char increases with the heating rate at pyrolysis. This is due to the coarseness (surface morphology)of biomass char and rough texture, which increases with the heating rate.
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