Assessing the potential of first generation ethanol production process by thermotolerant yeast

• Grant number: 16/06546-3
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): June 01, 2016
• Effective date (End): May 31, 2017
• Field of knowledge: Engineering - Chemical Engineering - Chemical Process Industries
• Principal researcher: Rosineide Gomes da Silva Cruz
• Grantee: Bruna Marques Tobal
• Home Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

This project has the purpose of giving continuity to the studies of first generation (1G) ethanol production process contributing to the research developed in the area of Biochemical Engineering of the Chemical Engineering Department at São Carlos Federal University. Despite of the use of a consolidate technology in Brazilian ethanol production process there is space for the implementation of improvements in the process. This project will be developed in the thematic area that involves the study of ethanol fermentation using a carbon source (reducing sugars) from sorghum and sugar cane. The 1G ethanol production by fermentative route consists of a series of chemical reactions catalyzed by the yeast Saccharomyces cerevisiae, usually in temperatures from 30 to 34ºC. During the process, there is the need for cooling the vats in order to keep the temperature constant. As temperature increase cell viability reduces causing a drop in the ethanol production. Thus, the search for yeasts which ferment at temperatures above 34ºC and that have good productivity in ethanol has been attracting attention in the literature. The proposed project aims to evaluate the ethanol production process using a thermotolerant yeast strain. Experiments will be carried out in shaker flasks in batch mode using temperatures ranging from 30 to 45ºC. The temperature that provides the better result in terms of ethanol productivity will be used in an experiment to be performed in a bioreactor. From experimental data kinetic parameters of the mathematical model of the process will be estimated. In previous work developed by the research group evaluating ethanol production by fermentation using CO2 as stripping gas, it was found that higher temperatures increased ethanol removal. Thus, this work can contribute to the use of higher temperatures in the ethanol production process by fermentation extraction, which was 34ºC so far.