A review on comprehensive strategies for decarbonizing bioethanol production process

Bioethanol plays a crucial role in the global transition to sustainability, serving as a renewable fuel especially in the transportation sector, and a versatile renewable chemical precursor in industries, mitigating greenhouse gas (GHG) emissions. Although bioethanol is renewable, its production is still carbon-intensive, with most emissions arising from fermentation and cogeneration. Despite significant advancements, existing works on bioethanol have largely focused on individual decarbonization elements (e.g., CCU, CCS in bioenergy, and process intensification in ethanol production). Few studies link these strategies together to show how they could collectively move bioethanol toward carbon-negative production. This review aims to fill that gap by systematically analyzing the evolution of bioethanol production processes, identifying key sources of CO2 emissions, and critically evaluating state-of-the-art strategies—including process optimization, CCU, and CCS—within a unified framework. Overall, this review underscores that integrating process optimization, CCU, and CCS can transform bioethanol production from a low-carbon fuel into a negative-emission technology, reinforcing its pivotal role in global decarbonization efforts.