AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production

Tongjun Liu, David Hodge

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

In this study, AHP pretreatment conditions, enzymatic hydrolysis and ethanol fermentation of switchgrass were investigated. Compare to different concentration of NaOH, to adjust the pH at 11.5 constantly during pretreatment can significantly enhance the efficient of bioconvertion from switchgrass to fermentable sugars such as glucose and xylose. Under this condition, the digestibility can reach 70%. The optimal conditions of enzymatic hydrolysis were using mixture of accelerase, xylanase and pectinase by the enzyme protein ratio of 63:27:10. The enzymatic hydrolysis conducted under this condition can get much higher xylose yield, which is 3 times of the yield before optimization. In fermentation step, comparison of different strains, Pichia stipitis CBS 6054, Saccharomyces cerevisiae GLBRC Y35, GLBRC 76 and 77 were tested. Meanwhile, different hydrolyzates were used in this study, which were detoxified (by using activated carbon), undetoxified enzymatic hydrolyzates, hydrolyzates with and without washing after pretreatment, hydrolyzate got from pretreated biomass with H 2SO 4 adjusting pH to 4.6-4.8 followed by enzymatic hydrolysis. The results showed that during pretreatment some inorganic (sodium from NaOH and sulfate used for pH adjustment) and organic (aromatics which were derived from lignin, acetate which came from hemicellulose, and other oxidation products such as aliphatic carboxylic acids) inhibitors could be generated. p-coumaric acid and ferulic acid are components of lignin in grasses, which can go into solutions under alkaline conditions and also can be removed by activated carbon. Process integration challenges AHP pretreatment at higher solids loadings which are necessary for producing ethanol of high titers as concentrations of these soluble fermentation inhibitors increase simultaneously.

LanguageEnglish (US)
Title of host publication11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings
StatePublished - 2011
Event2011 AIChE Annual Meeting, 11AIChE - Minneapolis, MN, United States
Duration: Oct 16 2011Oct 21 2011

Other

Other2011 AIChE Annual Meeting, 11AIChE
CountryUnited States
CityMinneapolis, MN
Period10/16/1110/21/11

Profile

Enzymatic hydrolysis
Fermentation
Ethanol
ferulic acid
Xylose
Lignin
Activated carbon
Polygalacturonase
Acids
Corrosion inhibitors
Carboxylic Acids
Carboxylic acids
Washing
Sugars
Yeast
Sulfates
Glucose
Acetates
Biomass
Enzymes

ASJC Scopus subject areas

  • Chemical Engineering(all)

Cite this

Liu, T., & Hodge, D. (2011). AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production. In 11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings

AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production. / Liu, Tongjun; Hodge, David.

11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings. 2011.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Liu, T & Hodge, D 2011, AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production. in 11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings. 2011 AIChE Annual Meeting, 11AIChE, Minneapolis, MN, United States, 10/16/11.
Liu T, Hodge D. AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production. In 11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings. 2011.
Liu, Tongjun ; Hodge, David. / AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production. 11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings. 2011.
@inproceedings{e0c01aac1b4a4b689298705d6d5a49f9,
title = "AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production",
abstract = "In this study, AHP pretreatment conditions, enzymatic hydrolysis and ethanol fermentation of switchgrass were investigated. Compare to different concentration of NaOH, to adjust the pH at 11.5 constantly during pretreatment can significantly enhance the efficient of bioconvertion from switchgrass to fermentable sugars such as glucose and xylose. Under this condition, the digestibility can reach 70{\%}. The optimal conditions of enzymatic hydrolysis were using mixture of accelerase, xylanase and pectinase by the enzyme protein ratio of 63:27:10. The enzymatic hydrolysis conducted under this condition can get much higher xylose yield, which is 3 times of the yield before optimization. In fermentation step, comparison of different strains, Pichia stipitis CBS 6054, Saccharomyces cerevisiae GLBRC Y35, GLBRC 76 and 77 were tested. Meanwhile, different hydrolyzates were used in this study, which were detoxified (by using activated carbon), undetoxified enzymatic hydrolyzates, hydrolyzates with and without washing after pretreatment, hydrolyzate got from pretreated biomass with H 2SO 4 adjusting pH to 4.6-4.8 followed by enzymatic hydrolysis. The results showed that during pretreatment some inorganic (sodium from NaOH and sulfate used for pH adjustment) and organic (aromatics which were derived from lignin, acetate which came from hemicellulose, and other oxidation products such as aliphatic carboxylic acids) inhibitors could be generated. p-coumaric acid and ferulic acid are components of lignin in grasses, which can go into solutions under alkaline conditions and also can be removed by activated carbon. Process integration challenges AHP pretreatment at higher solids loadings which are necessary for producing ethanol of high titers as concentrations of these soluble fermentation inhibitors increase simultaneously.",
author = "Tongjun Liu and David Hodge",
year = "2011",
language = "English (US)",
isbn = "9780816910700",
booktitle = "11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings",

}

TY - GEN

T1 - AHP pretreatment, high solid loading enzymatic hydrolysis and fermentation of switchgrass for ethanol production

AU - Liu,Tongjun

AU - Hodge,David

PY - 2011

Y1 - 2011

N2 - In this study, AHP pretreatment conditions, enzymatic hydrolysis and ethanol fermentation of switchgrass were investigated. Compare to different concentration of NaOH, to adjust the pH at 11.5 constantly during pretreatment can significantly enhance the efficient of bioconvertion from switchgrass to fermentable sugars such as glucose and xylose. Under this condition, the digestibility can reach 70%. The optimal conditions of enzymatic hydrolysis were using mixture of accelerase, xylanase and pectinase by the enzyme protein ratio of 63:27:10. The enzymatic hydrolysis conducted under this condition can get much higher xylose yield, which is 3 times of the yield before optimization. In fermentation step, comparison of different strains, Pichia stipitis CBS 6054, Saccharomyces cerevisiae GLBRC Y35, GLBRC 76 and 77 were tested. Meanwhile, different hydrolyzates were used in this study, which were detoxified (by using activated carbon), undetoxified enzymatic hydrolyzates, hydrolyzates with and without washing after pretreatment, hydrolyzate got from pretreated biomass with H 2SO 4 adjusting pH to 4.6-4.8 followed by enzymatic hydrolysis. The results showed that during pretreatment some inorganic (sodium from NaOH and sulfate used for pH adjustment) and organic (aromatics which were derived from lignin, acetate which came from hemicellulose, and other oxidation products such as aliphatic carboxylic acids) inhibitors could be generated. p-coumaric acid and ferulic acid are components of lignin in grasses, which can go into solutions under alkaline conditions and also can be removed by activated carbon. Process integration challenges AHP pretreatment at higher solids loadings which are necessary for producing ethanol of high titers as concentrations of these soluble fermentation inhibitors increase simultaneously.

AB - In this study, AHP pretreatment conditions, enzymatic hydrolysis and ethanol fermentation of switchgrass were investigated. Compare to different concentration of NaOH, to adjust the pH at 11.5 constantly during pretreatment can significantly enhance the efficient of bioconvertion from switchgrass to fermentable sugars such as glucose and xylose. Under this condition, the digestibility can reach 70%. The optimal conditions of enzymatic hydrolysis were using mixture of accelerase, xylanase and pectinase by the enzyme protein ratio of 63:27:10. The enzymatic hydrolysis conducted under this condition can get much higher xylose yield, which is 3 times of the yield before optimization. In fermentation step, comparison of different strains, Pichia stipitis CBS 6054, Saccharomyces cerevisiae GLBRC Y35, GLBRC 76 and 77 were tested. Meanwhile, different hydrolyzates were used in this study, which were detoxified (by using activated carbon), undetoxified enzymatic hydrolyzates, hydrolyzates with and without washing after pretreatment, hydrolyzate got from pretreated biomass with H 2SO 4 adjusting pH to 4.6-4.8 followed by enzymatic hydrolysis. The results showed that during pretreatment some inorganic (sodium from NaOH and sulfate used for pH adjustment) and organic (aromatics which were derived from lignin, acetate which came from hemicellulose, and other oxidation products such as aliphatic carboxylic acids) inhibitors could be generated. p-coumaric acid and ferulic acid are components of lignin in grasses, which can go into solutions under alkaline conditions and also can be removed by activated carbon. Process integration challenges AHP pretreatment at higher solids loadings which are necessary for producing ethanol of high titers as concentrations of these soluble fermentation inhibitors increase simultaneously.

UR - http://www.scopus.com/inward/record.url?scp=84857228823&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84857228823&partnerID=8YFLogxK

M3 - Conference contribution

SN - 9780816910700

BT - 11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings

ER -