Intensified synthesis of bioethanol from sustainable biomass

Abstract

The need for alternate energy resources has significantly increased in recent years due to the rapid depletion of currently available resources and strain on economic and environmental conditions. Production of biofuels from the sustainable lignocellulosic feedstocks can be one of the promising approaches to meet the energy requirements in an renewable fashion also minimizing the impact on environment. The production process is usually comprised of three processing steps as pretreatment for the removal of lignin, hydrolysis to yield fermentable sugars followed by actual fermentation giving biofuels like bioethanol, bio-butanol, bio-hydrogen, and biogas. The current chapter provides an overview of potential sustainable feedstock with subsequent discussion on different processes for pretreatment with an objective of intensifying the biofuel production. Dilute acid pretreatment, alkaline hydrolysis, and steam explosion have been established to be the generally applicable processes for pretreatment. Also the use of ultrasound, microwave, and hydrodynamic cavitation has been demonstrated to give process intensification in different processing steps including pretreatment, hydrolysis and fermentation overviewed in the work with specific reference to bioethanol production. Employment of these intensified processes can help in efficient processing of sustainable lignocellulosic feedstock like sugarcane waste, corn waste, food waste, paper waste, etc. which can lead to energy generation from renewable resources in economically efficient manner also giving the advantage of waste utilization.