Value addition on bioethanol produced from different feedstocks: a review of recent outlook

Abstract

The present review explores the value-added potential of bioethanol production from a variety of feedstocks, focusing on advancements in technology and sustainability. It emphasizes the use of different feedstocks, including agricultural residues, non-food biomass, and algae, which offer advantages over traditional food-based crops by avoiding the competition with food resources and enhancing environmental sustainability. Technological innovations such as genetic engineering and synthetic biology have improved the efficiency of bioethanol production by developing engineered microorganisms that are better at converting biomass into bioethanol. The adoption of consolidated bioprocessing, where several steps of bioethanol production are combined into one, has reduced processing time and costs, making bioethanol production more economically feasible. The present work underscores the importance of life cycle assessments in determining the environmental impact of bioethanol regarding the reduction of greenhouse gas emissions. Electricity co-generation is an important consideration in bioethanol production as the process requires significant heat but relatively low electricity. The approach is common in bioethanol production from sugarcane, where surplus biomass is used to generate heat and electricity, enhancing energy efficiency. This not only reduces the environmental impact by minimizing waste but also enhances the economic efficiency of the bioethanol production process by creating additional revenue streams. Such a transformation process contributes to a sustainable production cycle, maximizing resource use, reducing costs, and supporting environmental conservation. From an economic perspective, the present work highlights the need for policy support and government incentives to make bioethanol more competitive with fossil fuels. Besides, the potential of bioethanol as a feedstock for producing bioplastics and bio-based chemicals, its expanding applications, and economic benefits are discussed. Future research into enhancing feedstock diversity, optimizing bioprocessing techniques, and ensuring sustainability in bioethanol production is suggested.