Pyrolysis and CO<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si56.svg" display="inline" id="d1e1609"><mml:msub><mml:mrow /><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math> gasification of barley straw: Effect of particle size distribution and chemical composition

We evaluate how the heterogeneity of precursor may affect pyrolysis and CO2 gasification behavior aimed at activated carbon applications. Barley straw, ground classified into five size ranges, is characterized by non-isothermal thermogravimetry tests various heating rates. Fixed volatile matter contents decrease with particle size. Also, finest fraction enriched in minerals exogenous contamination accumulation silicon-rich leaves. Faster kinetics are found for small sizes, caused their higher alkali heat-mass transfer Char-CO2 conversion rates show an unexpected behavior, not previously reported. Higher reactivity fraction, decreasing significantly temperatures beyond 750 °C. The high content promotes catalytic effect on lower temperatures, hindering reaction forming low-melting-point potassium silicates. Results help improve pretreatment strategies to enhance quality.