Renewable energy sources, such as biofuels, represent promising alternatives to reduce dependence on fossil fuels and mitigate climate change. Their production through enzymatic hydrolysis has gained relevance by converting agro-industrial waste into fermentable sugars and residual oils, which are essential for the generation of bioethanol and biodiesel. The fungus Aspergillus stands out as a key source of enzymes, including cellulases, xylanases, amylases, and lipases, which are crucial for the breakdown of biomass and oils to produce bioethanol and fatty acid methyl esters (FAME). This review examines the current state of these technologies, highlighting the significance of Aspergillus in the conversion of energy-rich waste materials. While the process holds significant potential, it faces challenges such as the high costs associated with enzymatic production and final processing stages. Agro-industrial waste is proposed as an energy resource to support a circular economy, thereby eliminating reliance on non-renewable resources in these processes. Furthermore, advanced pretreatment technologies—including biological, physical, and physicochemical methods, as well as the use of ionic liquids—are explored to enhance process efficiency. Innovative technologies, such as genetic engineering of Aspergillus strains and enzyme encapsulation, promise to optimize sustainable biofuel production by addressing key challenges and advancing this technology towards large-scale implementation.

Biorefineries play a crucial role in the transition towards a circular economy by integrating biomass valorization into different products and energy sources. This article provides a comprehensive overview of the historical and technological advancements in the utilization of lignocellulosic biomass in biorefinery. It discusses the optimization of operational parameters at laboratory, pilot, and industrial scales, highlighting the progress made in bioenergy technologies. Furthermore, it addresses the global implementation of biorefinery by incorporating political aspects and their impacts. This study outlines insights and guidelines regarding future directions for the large-scale deployment of biorefinery, contributing to the promotion of an environmentally sustainable circular economy. Perspectives include enhancing process integration and developing innovative biomass conversion processes to further optimize biorefinery operations and maximize resource efficiency. Additionally, ongoing efforts to streamline regulatory frameworks and foster international collaboration will play a pivotal role in accelerating global implementation of biorefinery.