Pré-tratamento alcalino e hidrólise enzimática do capim-elefante (pennisetum purpureum) para obtenção de açúcares fermentescíveis

Abstract

The progressive depletion of fossil fossil reserves and the need to protect the environment demonstrate the need for a change in the current energy scenario. Although Brazil is the second largest producer of ethanol, it is still necessary to diversify the production matrix, expanding the portion of the parcel. Second-generation ethanol is still considered a new process, which produces quantities of reducing sugars from lignocellulosic biomass, and stands out for allowing the increase of bioethanol production in already installed plants, without an increase in cultivated areas, as well. how it promotes the use of agricultural residues, cereal grains and pastures. Therefore, there is a need for studies with different raw materials, especially low-cost biomass, which have great availability and production potential, such as elephant grass (Pennisetum purpureum). On the other hand, the second generation bioethanol production process cannot be aggressive to the environment and, therefore, it is necessary to reduce the chemical agents used, such as Sodium Hydroxide (NaOH). In this context, the objective of this work was to study the best experimental condition for obtaining fermentable sugars, reduction and reduction of the chemical agent. Therefore, different conditions of the process parameters of the alkaline chemical pretreatment were studied, as well as the physical pretreatment. Thus, in the present work it was verified by Tukey test with 95% confidence, that the concentration of the chemical agent NaOH used by the research group in enzymatic and microbiological processes (GPPEN) of the Federal University of Fronteira Sul (Campus Chapecó) can be reduced from 0,20 to 0,15 g / g biomass, obtaining the same results. There is no need to increase the autoclave pressure from 1,1 to 1,3 bar, but it is necessary to increase the time of this equipment (from 0,5 to 1 hour) and the incubation time (from 24 to 48 hours) when reducing the amount of chemical agent NaOH by 25%.