Lime Pretreatment and Fermentation of Enzymatically Hydrolyzed Sugarcane Bagasse

Author(s)

Rabelo, Sarita C. ^[1] ; Maciel Filho, Rubens ^[1] ; Costa, Aline C. ^[1]

Affiliation

^[1] Univ Estadual Campinas, UNICAMP, Sch Chem Engn, BR-13083970 Campinas, SP - Brazil

• Document type: Journal article
• Source: Applied Biochemistry and Biotechnology; v. 169, n. 5, p. 1696-1712, MAR 2013.
• Web of Science Citations: 14

Abstract

Sugarcane bagasse was subjected to lime (calcium hydroxide) pretreatment and enzymatic hydrolysis for second-generation ethanol production. A central composite factorial design was performed to determine the best combination of pretreatment time, temperature, and lime loading, as well as to evaluate the influence of enzymatic loadings on hydrolysis conversion. The influence of increasing solids loading in the pretreatment and enzymatic hydrolysis stages was also determined. The hydrolysate was fermented using Saccharomyces cerevisiae in batch and continuous mode. In the continuous fermentation, the hydrolysates were concentrated with molasses. Lime pretreatment significantly increased the enzymatic digestibility of sugarcane bagasse without the need for prior particle size reduction. In the optimal pretreatment conditions (90 h, 90 A degrees C, 0.47 g lime/g bagasse) and industrially realistic conditions of hydrolysis (12.7 FPU/g of cellulase and 7.3 CBU/g of beta-glucosidase), 139.6 kg lignin/ton raw bagasse and 126.0 kg hemicellulose in the pretreatment liquor per ton raw bagasse were obtained. The hydrolysate from lime pretreated sugarcane bagasse presented low amounts of inhibitors, leading to ethanol yield of 164.1 kg ethanol/ton raw bagasse. (AU)

• FAPESP's process: 07/01525-9 - Evaluation of pre-treatment and modeling of enzymatic hydrolysis of sugar cane bagasse for ethanol production
• Grantee: Sarita Candida Rabelo
• Support Opportunities: Scholarships in Brazil - Doctorate