Recent advances in the valorization of waste biomass materials for heterogeneous catalysts towards biodiesel production: a review

The increasing global energy demand, depletion of fossil fuel reserves, and environmental degradation have motivated research into sustainable alternatives, with biodiesel emerging as a promising renewable energy source. Heterogeneous catalysts are preferred for biodiesel production because of their activity, reusability, and capacity to support the circular economy through the use of waste-derived precursors. In particular, the benefits of using biobased precursors for heterogeneous catalyst synthesis need to be further explored. Previous reviews on this subject often focus on general catalyst types, without providing a focused discussion on the specificities of waste-derived catalysts. This provides a limited understanding of the unique benefits, challenges, and sustainability implications of waste-derived catalysts. The current review addresses these gaps by providing a comprehensive evaluation of the advancements in heterogeneous catalysts derived from bio-based precursors for biodiesel synthesis. Various catalyst types, including acidic, basic, bifunctional, and nanostructured catalysts, were analyzed, with a focus on their synthesis methods, performance, and limitations. The findings reveal that bio-derived heterogeneous catalysts offer distinct advantages, such as catalytic activity, porosity, high thermal stability, reusability, and reduced environmental impact, making them suitable for large-scale biodiesel production. However, challenges such as active site leaching, sensitivity to impurities, and fouling were identified, highlighting the need for innovative solutions. The review also emphasizes the role of advanced synthesis techniques in enhancing catalyst performance. This study highlights the potential of bio-derived catalysts in promoting sustainable energy production and calls for further research to optimize their scalability, cost-effectiveness, and integration into industrial biodiesel production systems. • Reviews recent advances in biomass-derived heterogeneous catalysts for biodiesel. • Examines synthesis routes linking structure, stability, and catalytic activity. • Compares the performance of some waste-derived catalysts for sustainable production. • Highlights characteristics and their influence on productivity. • The review identifies future pathways for sustainable biodiesel.