2 - Lignocellulosic biomass: A feedstock to support the circular economy

Abstract

Lignocellulosic biomass (LCB) is a promising sustainable material for future liquid fuel. The diminishing fossil fuel reserves and negative environmental effects have driven accelerated research in the biofuels domain. Agroindustrial waste-derived LCB is a competitive nonfood feedstock for the sustainable production of critical liquid fuels, such as bioethanol or biobutanol, and chemical compounds through biorefinery processes. Cellulose, hemicellulose, and lignin are the primary components of LCB. Large quantities of sugars present in cellulose and hemicellulose can be biochemically synthesized using acid as a catalyst or enzymatically destroyed and converted into biofuels via fermentation. Catabolic enzymes reduce the pretreatment of lignocelluloses to simple sugars in hydrolysis reactors during bioethanol production from LCB. Intriguing pretreatment methods based on biological approaches to enhance the efficacy of bioconversion processes and overcome barriers to the commercialization of renewable biorefineries are required to increase the efficiency of bioconversion processes and remove obstacles to their commercialization. The efficient and cost-effective bioethanol production from LCB depends on developing a suitable pretreatment method. Several combinations of bioethanol, biohydrogen, biojet fuel, biomethane, and biodiesel have been evaluated in a biorefinery system, and their potential has been proven to be substantial. Several alternative pretreatment techniques, such as physical, chemical, biological, or a combination of these, help to improve lignocellulose breakdown, thereby decreasing the recalcitrance biomass and enabling enzyme access to their substrates. Nonetheless, the pretreatment of lignocellulosic materials generates several lignocellulose-derived byproducts that inhibit microbial growth and fermentation yields. The present work focuses on the sustainable utilization of lignocellulosic waste biomass, its pretreatment, and its utilization as a feedstock for biofuel production in a biorefinery.