Avaliação da produção de etanol de segunda geração

Abstract

Currently, sustainability has had an important place in society. It is increasingly necessary to find ways to live in balance with nature, in order to not to exhaust natural resources, nor to cause situations of environmental imbalance, which can cause damage and even dangers to human life. In this context, the search for alternatives to renewable energy sources, replacing non-renewable sources, has an important aspect. This work is a bibliographical evaluation of the production of second-generation ethanol, a process where lignocellulosic feedstock is used, which is abundant in nature and has as its final product a sustainable alternative to fossil fuels. Firstly, an introduction is made, which describes the general aspects of Brazil's current energy supply, some definitions and a brief history of ethanol production in Brazil, as well as possible raw materials for ethanol production. Next, the main steps of the production process are explored, such as pretreatments, hydrolysis and fermentation. The pretreatments are physical (size reduction, pyrolysis and irradiation), physical-chemical (pretreatment with hot water, steam explosion and fiber explosion with ammonia), chemicals (acid pretreatment, basic pretreatment and organosolv), and the biological ones. After, an analysis of the hydrolysis of the lignocellulosic material is done, and lastly, the main aspects on the fermentation are reported to obtain the ethanol.