Kinetics of acid hydrolysis of the liquid stream of hydrothermal Pretreament

• Grant number: 13/05369-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: July 01, 2013
• End date: April 30, 2015
• Field of knowledge: Engineering - Chemical Engineering
• Principal Investigator: Aline Carvalho da Costa
• Grantee: Pedro Yoritomo Souza Nakasu
• Host Institution: Faculdade de Engenharia Química (FEQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 08/57873-8 - An integrated process for total bioethanol production and zero CO2 emission, AP.BIOEN.TEM

Abstract

Although the hydrothermal pretreatment is considered very promising as it uses an environmentally friendly solvent (water), leads to high recovery of pentoses and reduces inhibitors formation, the hydrolysis process of the hemicelluloses is not complete, resulting in high xylooligosaccharides formation. As these compounds cannot be directly fermented, a post-hydrolysis step is indispensable for the total utilization of the pentoses.Although the acid post-hydrolysis has more economic advantages, it can lead to a significant degradation of the monosaccharides and formation of compounds that inhibit the posterior fermentation. The use of dicarboxylic organic acids (maleic and oxalic) can be a good alternative to obtain hydrolysates with lower levels of inhibitors. In comparison with sulfuric acid, the most used acid in hydrolysis processes, these acids are less corrosive and more selective.Within this context, in this project a kinetic study of the post-hydrolysis of the hemicellulosic hydrolysate obtained from hydrothermal pretreatment of sugarcane bagasse will be performed. Maleic, oxalic and sulfuric acids will be compared in terms of xylose yield and selectivity as a function of the severity factor. Also, the hydrolysis liquid streams will be fermented by the wild yeast Scheffersomyces stipitis NRRL Y7124 (formerly named Pichia stipitis), capable of fermenting xylose. Once the results are obtained, mass balances for the ethanol production process from hydrothermically pretreated bagasse will be performed, considering fermentation of the hexoses obtained from the enzymatic hydrolysis of the solid fraction of the pretreatment and fermentation of the pentoses from the post-hydrolysis of the liquid fraction of the pretreatment. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

NAKASU, P. Y. S.; CHAGAS, M. F.; COSTA, A. C.; RABELO, S. C.. Kinetic Study of the Acid Post-hydrolysis of Xylooligosaccharides from Hydrothermal Pretreatment. BioEnergy Research, v. 10, n. 4, p. 1045-1056, DEC 2017. (13/05369-2)

NAKASU, P. Y. S.; IENCZAK, L. J.; COSTA, A. C.; RABELO, S. C.. Acid post-hydrolysis of xylooligosaccharides from hydrothermal pretreatment for pentose ethanol production. FUEL, v. 185, p. 73-84, DEC 1 2016. (13/05369-2)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

NAKASU, Pedro Yoritomo Souza. Kinetics of acid hydrolysis of the pretreatment liquor obtained by hydrothermal pretreatment. 2015. Master's Dissertation - Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Química Campinas, SP.