Combined Sedimentation and Filtration Process for Cellulase Recovery During Hydrolysis of Lignocellulosic Biomass
A combined sedimentation and ultrafiltration process was investigated for recovering cellulase enzymes during the hydrolysis of lignocellulosic biomass. Lignocellulosic particles larger than approx 50 µm in length were first removed via sedimentation using an inclined settler. Ultrafiltration was then used to retain the remaining lignocellulosic particles and the cellulose enzymes, while transmitting fermentable sugars and other small molecules. The permeate flux from the ultrafiltration step for a feed consisting of 0.22 w/v% cellulase is 64 ± 5 L/m2-h, while that for a feed consisting of the settler overflow from a mixture 0.22 w/v% cellulase and 10 wt% lignocellulose fed to the settler is 130 ± 20 L/m2-h. The higher permeate flux in the latter case is presumably due to binding of a portion of the cellulase enzymes to the lignocellulosic particles during hydrolysis and filtration, preventing the enzymes from fouling the membrane. A filter paper activity assay shows little loss in enzymatic activity throughout the combined sedimentation/ultrafiltration separation process.
KeywordsApply Biochemistry Lignocellulosic Biomass Total Protein Feed Solution National Renewable Energy Laboratory
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- 2.McCoy, M. (1998), Chemical Engineering News 76, 29–32.Google Scholar
- 4.Wooley, R., Ruth, M., Sheehan, J., Ibsen, K., Madjeski, H., and Galvez, A. (1999), Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis Current and Futuristic Scenarios, National Renewable Energy Laboratory, Golden, CO.CrossRefGoogle Scholar
- 21.Tan, L. U. L., Yu, E. K. C., Mayers, P., and Saddler, J. N. (1986), Appl. Microbiol. Biotech. 25, 256–261.Google Scholar
- 27.Kaya, F., Heitmann, J. A., and Joyce, T. W. (1996), Cellulose Chem. Technol. 30, 49–56.Google Scholar
- 31.McMillan, J. D., Dowe, N., Mohagheghi, A., and Newman, M. (1999), Reducing the Cost of Saccharification and Fermentation by Decreasing the Cellulase Enzyme Loading Required for Cellulose Conversion, National Renewable Energy Laboratory, Golden, CO.Google Scholar