Effect of fast pyrolysis conditions on structural transformation and reactivity of herbaceous biomasses at high temperatures

□The results of the ²⁹Si solid-state NMR study indicated that the silicates in rice husk chars were mainly amorphous □No significant changes appeared in the ²⁹Si solid-state NMR for Q², Q³ and Q⁴ branches of rice husk chars □The presence of silicates in the rice husk affected the obtained char morphology by the formation of a glassy char shell due to the softening of the amorphous silicon oxides □Silicates present in rice husk chars did not affect the reactivity in oxidation □High alkali content in wheat straw increased the char reactivity.