Wheat straw is a renewable agricultural by-product that is currently underutilized in the production of bioenergy and bioproducts due to its high ash content, as well as high transport costs due to its low volumetric energy density. The thermogravimetric analysis of this material produces derivative curves with a single broad peak, making it difficult to identify the three conventional pseudo-components (cellulose, hemicellulose, and lignin), which is resolved using the second derivative to determine inflection points. Model-fitting methods and isoconversional methods were applied to determine the degradation kinetics of wheat straw at two different particle sizes, as well as that of a reference feedstock (beech wood), and the obtained values were used to divide the degradation curves to be compared to the experimental data. Seven different pyrolysis reaction networks from the literature were given a similar treatment to determine which provides the best estimation of the actual pyrolysis process for the case of the feedstocks under study. The impact of the potassium content in the feedstock was considered by comparing the original pathway with a modification dependent on the experimental potassium content and an estimated optimum value.
Lignin is the second most abundant renewable material after cellulose. However, its economic use is currently relegated to low‐value energy production. This biomaterial holds great potential as a source of renewable biofuels, bio‐based chemicals, advanced materials, and integrated biorefineries. Fractionation and depolymerization methods yield liquid repositories of promising aromatic monomers and lignin oligomers (LO) that retain many of the structural components found in the native material. However, analyzing this complex mixture is challenging due to the wide range of molecular sizes and heterogeneous chemical structure, which makes their structural elucidation a critical obstacle – unlocking the full potential of lignin hinges upon developing appropriate standards and analytical methods to address existing knowledge gaps. This review provides a comprehensive examination of current analytical techniques for elucidating the chemical structure of lignin oligomers, exploring synthesis methods, molecular structures, and their advantages and limitations. Built upon these findings, opportunities for synergy between synthetic oligomers and lignin utilization can be revealed, such as bioactive compound production and biorefinery integration. Moreover, we underscore the need for standardized analytical methods to facilitate the design of lignin oligomer standards and their diverse applications.