Raffaele Loffredo

Lignin valorization represents a key opportunity for advancing sustainable and circular bio-based economies, yet its techno-economic feasibility remains uncertain due to feedstock variability and limited process standardization. This study aims to critically assess the current state of lignin valorization by analyzing process modelling, simulation-based techno-economic studies, and evaluating the market of major lignin-derived products. Data from the literature were used to estimate process yields, energy requirements, and economic indicators such as net present value and payback selling price across multiple conversion pathways. The analysis shows that economic performance strongly depends on both lignin type and targeted product. High-value, low-volume products such as vanillin and phenolic compounds emerge as the most economically promising despite relatively low yields, while bulk chemicals and fuels, including BTX aromatics, remain less competitive under current technological conditions. Lignin-based carbon fibers and resins exhibit significant potential in advanced materials applications, although their large-scale deployment is still constrained by high production costs and intermediate technology readiness levels. Overall, the results highlight that improved feedstock standardization, process integration, and data reliability are essential to enhance comparability and scalability. A more targeted alignment between lignin types and applications, supported by coordinated research and policy frameworks, is necessary to accelerate the transition toward commercially viable lignin-based value chains.