Boundaries and openings of biorefineries towards sustainable biofuel production

In recent days, the unlimited usage of fossil fuels due to human, environmental, and social activities results in the depletion of natural availabilities and rise in global warming. Fossil fuel, the only source that provides energy, is decreased simultaneously, and there is a need for alternate sources. To meet the energy crisis, biofuels are a promising source for the energy generation because they are sustainable in nature and are easy to blend. Biorefineries are generally regarded as conversion of biomass into other beneficial products from the refineries. Need for the agricultural wastes such as sugarcane bagasse and paddy straw and industrial wastes such as paper, pulp industries, and cassava are enriched in cellulosic components. Hemicellulose and lignin, generally known as lignocellulosic compounds, also present in this biomass. These kinds of biomasses can be utilized for biofuel production along with some by-products. Different conversional techniques involve transesterification, acid hydrolysis, and some enzymatic methods are used for the treatment of biomass. This chapter will address the pretreatment methods, conversion of biomasses into biofuels, and purification process.