Sustainable biofuel production from marine macroalgae: strategic pathways for a decarbonized circular bioeconomy

Abstract Global energy demands and fossil fuel environmental impacts necessitate sustainable renewable alternatives. Seaweed (macroalgae), as a third-generation feedstock, offers a promising solution. This review evaluates the potential of seaweed-derived biofuels, including bioethanol, biogas, and biodiesel. It examines the classification, morphology, and biochemical composition of brown, red, and green algae, highlighting their suitability for biomass conversion. Furthermore, the review analyzes cultivation methodologies, essential pretreatment techniques, and specific biochemical pathways for biofuel production. While acknowledging seaweed’s potential, critical challenges are addressed, including cultivation demands, species specificity, complex biomass structures, cost-effectiveness, and scalability. Special emphasis is placed on regional perspectives and policy hurdles in the Arab world. By synthesizing current advancements, this review provides strategic insights into seaweed-based biorefineries’ role in fostering a circular bioeconomy, contributing to global energy security and environmental sustainability.