Perspectives and Progress in Bioethanol Processing and Social Economic Impacts
Mario Alberto Yaverino-Gutiérrez, Alán Yazid Chávez-Hita Wong, Lizbeth Ibarra-Muñoz, Ana Cristina Figueroa Chávez, Jazel Doménica Sosa-Martínez, Ana Sofia Tagle-Pedroza, Javier Ulises Hernández‐Beltrán, Salvador Sánchez-Muñoz, Joana Carolina Freire Sandes Santos, Sílvio Silvério da Silva, Nagamani Balagurusamy
Abstract
The liquid biofuel bioethanol is widely produced worldwide via fermenting sugars extracted from a variety of raw materials, including lignocellulose biomass, one of the world’s most abundant renewable resources. Due to its recalcitrant character, lignocellulose is usually pretreated by mechanical, chemical, and biological methods to maximize sugar recovery. Pretreated lignocellulose biomass undergoes a fermentation process performed sequentially or simultaneously to saccharification. The different fermentation strategies (e.g., separate or simultaneous hydrolysis and fermentation or co-fermentation) and conditions (e.g., inoculum type load, agitation, temperature, and pH) affect ethanol yield. Genetic modification of the inoculum has been focused recently to improve ethanol tolerance and as well as to use different sugars to enhance the performance of the microorganisms involved in fermentation. Nonetheless, these improvements result in a substantial increase in costs and have certain environmental costs. This review offers an overview of advancements in bioethanol production, with a primary focus on lignocellulosic feedstock, while also considering other feedstocks. Furthermore, it provides insights into the economic, social, and environmental impacts associated with bioethanol production.