Sustainable Biodiesel Production with Heterogeneous Catalysts: Insights from a Systematic Literature Review

Abstract

This study reviews advancements in biodiesel production using heterogeneous catalysts guided by the PRISMA framework. It emphasizes the potential of waste-derived, cost-effective catalysts for sustainable biodiesel synthesis. Results reveal that CaO/hectorite achieves a 95% yield with reusability for seven cycles. With magnetic properties, the CaO/MgO/Fe₃O₄ magnetite catalyst yields 95.64% and ensures easy recovery. An eco-friendly CaO catalyst from shrimp shell waste delivers a 97.1% yield, highlighting effective waste utilization. Amidoxime-modified PAN fibres convert 94% of stearic acid but show reduced efficiency after 13 cycles. Optimal conditions include reaction temperatures of 55 to 65°C, methanol-to-oil ratios of 10.5:1 to 18:1, and catalyst loadings of 3 to 8%. These parameters consistently improve yields and catalyst reusability. Advanced methods, such as Response Surface Methodology (RSM), enhance performance optimization. Material characterization tools like XRD, SEM, and FTIR validate catalysts' structural integrity and effectiveness. Emerging techniques, including microwave heating and machine learning models, significantly enhance process efficiency while reducing costs. This review highlights the novelty of integrating waste-derived catalysts with innovative optimization techniques for scalable biodiesel production. Future work should focus on extending the catalyst lifespan and enhancing stability under industrial conditions. These developments support sustainable biodiesel production, aligning with ecological and economic objectives.