Advances in Bioethanol Production: Processes and Technologies

Abstract

Fossil fuels are the primary source of energy all over the world but generate undesirable health and environmental impacts. Biofuels are considered as the most potential alternative renewable sources of energy that can substitute fossil fuels. Bioethanol is currently the most important biofuel and produced from starch and lignocellulosic biomass. The process of production of bioethanol from biomass includes hydrolysis, fermentation and product purification. First-generation bioethanol is produced from starch obtained from various food crops leading to food vs fuel dilemma. Second-generation bioethanol can be produced from non-edible, non-food crops and waste biomass, but this process needs an additional expensive step of pretreatment. Many different methods of pretreatment are available, each with its own advantages and disadvantages: physical, physico-chemical, chemical and biological methods. Selection of the optimal and appropriate pretreatment methods, as well as other stages of the production of bioethanol, is important for the generation of bioethanol on a commercial scale. The present chapter discusses on different types of raw materials and biomass used and various steps and processes involved in the conversion of biomass into bioethanol. The chapter also describes the recent advances made and various strategies employed for improving technology of bioethanol production and making it commercially viable.