Bioethanol production from carbohydrate-enriched residual biomass obtained after lipid extraction of Chlorella sp. KR-1. (November 2015)

• Record Type: Journal Article
• Authors: Lee, Ok Kyung; Oh, You-Kwan; Lee, Eun Yeol
• Is Part Of: Bioresource technology. Volume 196(2015)
• Page Start: 22
• Page End: 27
• Publication Date: 2015-11
• Subjects: Chlorella sp. KR-1 -- Residual biomass -- Saccharification -- Bioethanol fermentation; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2015.07.040
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Chlorella sp. KR-1 was accumulated 36% (w/w) of carbohydrates and 38% (w/w) of lipids. The lipid was converted to biodiesel while lipid-extracted residual biomass was used for bioethanol fermentation. A saccharification yield of almost 100% was obtained using dilute acid method. A 0.4 g ethanol/g fermentable sugar and 0.16 g ethanol/g residual biomass were produced. Abstract: The residual biomass of Chlorella sp. KR-1 obtained after lipid extraction was used for saccharification and bioethanol production. The carbohydrate was saccharified using simple enzymatic and chemical methods using Pectinex at pH 5.5 and 45 °C and 0.3 N HCl at 121 °C for 15 min with 76.9% and 98.2% yield, respectively, without any pretreatment. The residual biomass contained 49.7% carbohydrate consisting of 82.4% fermentable sugar and 17.6% non-fermentable sugar, which is valuable for bioethanol fermentation. Approximately 98.2% of the total carbohydrate was converted into monosaccharide (fermentable + non-fermentable sugar) using dilute acid saccharification. The fermentable sugar was subsequently fermented to bioethanol through separate hydrolysis and fermentation with a fermentation yield of 79.3%. Overall, 0.4 g ethanol/g fermentable sugar and 0.16 g ethanol/g residual biomass were produced.