Reduction of fermentation lag phase in biofuel production using a novel activated biochar material

Authors: Klasson, K Thomas; Dien, Bruce; Hector, Ronald - Ron

Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/1/2012
Publication Date: 12/8/2012
Citation: Klasson, K.T., Dien, B.S., Hector, R.E. 2012. Reduction of fermentation lag phase in biofuel production using a novel activated biochar material. In: Proceedings of the U.S.-Japan Cooperative Program in Natural Resources Food and Agriculture Panel, USDA-ARS, December 8-13, 2012, Wyndmoor, Pennsylvania. pp. 1-2.

Interpretive Summary: Biomass feedstocks can be prepared for biofuel manufacture by treatment with a dilute acid that breaks down parts of the material in to smaller components that can be converted to bioethanol by fermentation. The reaction with acid often produces chemicals that are inhibitory to the later fermentation step. This work evaluates the use of agricultural wastes (flax shive) as starting materials for making activated biochars to remove these chemicals. Results show that the chemicals furfural and hydroxymethylfurfural are adsorbed by steam-activated biochar prepared from flax shive. Removal of these chemicals from the liquid significantly improved the fermentation behavior of the yeast, shortening the time of fermentation. No negative effects were noted from addition of activated biochar to the process.

Technical Abstract: Lignocellulosic feedstocks can be prepared for ethanol fermentation by treatment with a dilute mineral acid catalyst that hydrolyzes the hemicellulose and possibly cellulose into soluble carbohydrates. The acid catalyzed reaction scheme is sequential, whereby released monosaccharides are further degraded to furans and other chemicals that are inhibitory to the subsequent fermentation step. This work evaluates the use of agricultural residues (flax shive) as starting materials for making activated biochars to adsorb these degradation products. Results show that both furfural and hydroxymethylfurfural are adsorbed by steam-activated biochar prepared from flax shive. Decontamination of the hydrolyzates significantly improved the fermentation behavior of the Saccharomyces cerevisiae yeast, including significantly reducing the lag phase. No negative effects were noted from addition of activated biochar to the process.