Potassium-Induced Phenomena and Their Effects on the Intrinsic Reactivity of Biomass-Derived Char during Steam Gasification

Abstract

The mineral content of biomass plays an important role in the gasification rate of biomass-derived char. The understanding and quantification of mineral-related phenomena are thus of importance when considering gasification reactor design. In the present work, the potassium-induced catalytic phenomena during gasification of biomass-derived char have been studied. Char samples with similar structure and different intrinsic potassium content were gasified in a steam atmosphere at a temperature range of 700−800 °C. It was found that for all the samples, irrespective of the temperature and the initial potassium content, there is a critical K/C ratio (5 × 10 −3 ), whereafter the catalytic phenomena prevail. The instantaneous conversion rate of the char is positively correlated with the potassium content and the progressively increasing conversion. The application of the modified random pore model was able to capture the later stages of conversion by the introduction of two additional parameters (c and p). It was found that these constants are not just fitting parameters but that there is an underlying physical significance with c being directly related to the intrinsic potassium content while being temperature independent and with p being temperature dependent.

Influence of anionic species on the low temperature pyrolysis performance of heated tobacco sheets catalyzed by sodium salts

“…Currently, a variety of catalysts, including molecular sieves ( Carlson et al, 2011 ; Martinez and Corma, 2011 ; Zhang et al, 2011 ; Dickerson and Soria, 2013 ; Li et al, 2014 ; Jia et al, 2017 ; Dai et al, 2020 ; Liang et al, 2021 ; Mardiana et al, 2022 ), mesoporous materials ( Iliopoulou et al, 2007 ; Perego and Bosetti, 2011 ; Xu et al, 2012 ; Antunes et al, 2016 ; Herbst and Janiak, 2017 ; Shen et al, 2020 ), metal oxides ( Barta et al, 2014 ; Matson et al, 2011 ; O'Neill et al, 2015 ; Robinson et al, 2016 ; Thompson et al, 2015 ), and alkali/alkaline earth metals ( Xiong et al, 2021 ; Esso et al, 2022 ; Ge et al, 2022 ; Macedo et al, 2022 ; Wang et al, 2022 ; Ding et al, 2023 ), are widely employed in high temperature catalytic conversion processes for biomass. Heated tobacco sheets, as a unique type of biomass resource, have the potential to benefit from the application of these catalysts in low temperature catalytic pyrolysis.…”