Insight into the pyrolysis behavior of corn straw through TG-FTIR, Py-GC/ MS experiments and ReaxFF MD simulations

Corn straw is a renewable carbon-neutral fuel, which can be pyrolyzed to obtain a variety of high-quality chemical products. This work investigated the pyrolysis characteristics, product distribution, and main gas products formation of corn straw by experiments and ReaxFF-MD simulations. And the pyrolysis mechanism of the initial products (alcohols and certain furans) was analyzed. Based on TG-FTIR and Py-GC/MS experiments, the pyrolysis products of corn straw mainly included furans, phenols, acids, ketones, esters, and aldehydes. And the main gas products were H2O, CH4, CO, CO2, etc. Through kinetic analysis, the activation energy of corn straw pyrolysis decreased slightly with the increase of heating rate. After the corn straw model was built and verified, the pyrolysis behavior of the main pyrolysis products at different temperatures and heating rates was analyzed. The simulations showed that high yields of H2, CH4, bio-oil, and CH3OH could be obtained by controlling the reaction temperature. Moreover, the reaction proceeded more thoroughly with decreasing heating rate at the same temperature. And the yield of small molecular gases such as H2, H2O, CO, and CO2 was also higher.