Thermal decomposition of cellulosic materials: Insights into mechanisms and product evolution

This review provides an in-depth exploration of the thermal decomposition behavior of cellulose and cellulosic materials such as cotton and paper, with a focus on the underlying reaction mechanisms. Following a brief overview of the motivations behind studying cellulose decomposition, it introduces key concepts in thermal decomposition, specifically pyrolysis – namely in inert atmosphere – and thermo-oxidation. It then delves into the detailed pathways involved in cellulose decomposition, with special emphasis on the formation of volatile compounds, tar and char – carbon-rich residue. To offer a comprehensive understanding of this complex process, the review also examines the critical factors that influence the balance between volatilization and charring, including heating rate, moisture content, presence of metal ions, cellulose morphology and treatment with functional additives such as flame retardants. These elements are thoroughly discussed to present a complete and nuanced view of cellulose thermal decomposition.