Revolutionizing waste management through acetone–butanol–ethanol fermentation for green energy and advancing circular bioeconomy

Abstract

The fermentation of acetone-butanol-ethanol (ABE) has been used in industrial bioprocessing since the 1850s, and it has been regaining attention because of its potential for the creation of sustainable biofuels and bioproducts. Renewable energy sources with ABE fermentation, usually display lesser life cycle greenhouse gas emissions when compared to fossil-based energy system. However, their overall environmental performance depends on parameters such as feedstock type, process efficiency, and downstream processing. Therefore, ABE fermentation signifies a promising, though context-dependent, strategy for reducing air pollution and greenhouse gas emissions. The bioproduction of ABE involves various Clostridium species, which go through a unique two-phase metabolism pathway to produce the biofuel. While there are several challenges associated with ABE production, advances in genetic engineering, adaptive evolution, and synthetic biology help solve many problems to enhance fermentation efficiency. This review gives a rationalised overview of ABE fermentation by combining microbial, and process engineering aspects along with sustainability considerations. This work focuses on the combined importance of renewable feedstocks, process optimization, and circular bioeconomy approaches, supported by recent studies and current research trends. It also highlights the role of life cycle assessment in evaluating environmental impacts and identifying key challenges in the process. Overall, the review discusses the main limitations, and future research needs to improve the scalability, cost-effectiveness, and environmental performance of ABE fermentation, supporting its potential role in developing a sustainable bio-based economy.