The effect of particle size on hydrolysis reaction rates and rheological properties in cellulosic slurries
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The effect of varying initial particle sizes on enzymatic hydrolysis rates and rheological properties of sawdust slurries is investigated. Slurries with four particle size ranges (33 µm<x≤75 µm, 150 µm<x≤180 µm, 295 µm<x≤425 µm, and 590 µm<x≤850 µm) were subjected to enzymatic hydrolysis using an enzyme dosage of 15 filter paper units per gram of cellulose at 50°C and 250 rpm in shaker flasks. At lower initial particle sizes, higher enzymatic reaction rates and conversions of cellulose to glucose were observed. After 72 h 50 and 55% more glucose was produced from the smallest size particles than the largest size ones, for initial solids concentration of 10 and 13% (w/w), respectively. The effect of initial particle size on viscosity over a range of shear was also investigated. For equivalent initial solids concentration, smaller particle sizes result in lower viscosities such that at a concentration of 10% (w/w), the viscosity decreased from 3000 cP for 150 µm<x≤180 µm particle size slurries to 61.4 cP for 33 µm<x≤75 µm particle size slurries. Results indicate particle size reduction may provide a means for reducing the long residence time required for the enzymatic hydrolysis step in the conversion of biomass to ethanol. Furthermore, the corresponding reduction in viscosity may allow for higher solids loading and reduced reactor sizes during large-scale processing.
Index EntriesBiomass enzymatic hydrolysis non-Newtonian particle suspension red oak wood sawdust slurry viscosity
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- 2.McCloy, B. W. and O’Connor, D. V. (1999), Wood ethanol opportunities and barriers. Report for Forest Sector Table.Google Scholar
- 3.Robert, H. F. and McKeever, D. B. (2004), Recovering wood for reuse and recycling: a United States perspective. Management of Recovered Wood Recycling, Bioenergy and Other Options, Thessaloniki, European COST E31 Conference.Google Scholar
- 7.Charles E. W., Lee, Y. Y., Dale, B. E., et al. (2005), 2nd World Congress on Industrial Biotechnology and Bioprocessing.Google Scholar
- 10.Yerkes D. W., Zhang, H., Berson, E. R., Loha, V., Modi, S., and Tanner, R. D. (1995), Indina Chem. Eng. 37, 3, 80–89.Google Scholar
- 19.David, J. G. and John, N. S. (1996), Biotechnol. Bioeng. 51, 375–383.Google Scholar
- 24.Millett, M. A., Baker, A. J., and Scatter, L. D. (1976), Biotechnol. Bioeng. Symp. No. 6, 125–153.Google Scholar
- 25.Fan, L. T., Lee, Y., and Gharpuray, M. M. (1982), Adv. Biochem. Eng. 23, 157–187.Google Scholar
- 26.Ebeling, T., Paillet, M., Borsali, R., et al. (1999), Am. Chem. Soc. 15(19), 6123–6126.Google Scholar
- 27.Oldshue, J. Y. (1983), Fluid Mixing Technology, McGraw Hill, New York, NY.Google Scholar
- 28.Hodge, D., Karim, M. N., Farmer, J., Schell, D. J., and McMillan, J. D. (2005), 27th Symposium on Biotechnology for Fuels and Chemicals, Denver, CO, 1–4 May.Google Scholar