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.

    Original languageEnglish (US)
    Title of host publication11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings
    StatePublished - 2011
    Event2011 AIChE Annual Meeting, 11AIChE - Minneapolis, MN, United States

    Other

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

    Profile

    Enzymatic hydrolysis
    Fermentation
    Ethanol
    Xylose
    Lignin
    Activated carbon
    Acids
    Affinity Labels
    Butylene Glycols
    Corrosion inhibitors
    Carboxylic acids
    Washing
    Sugars
    Yeast
    Glucose
    Biomass
    Enzymes
    Sodium
    Proteins
    Oxidation

    ASJC Scopus subject areas

    • Chemical Engineering(all)

    Cite this

    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, 16-21 October.

    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.

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

    @inbook{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",
    isbn = "9780816910700",
    booktitle = "11AIChE - 2011 AIChE Annual Meeting, Conference Proceedings",

    }

    TY - CHAP

    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 -