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Jonathan J. Stickel

Photo of Jonathan J. Stickel

Jonathan Stickel is a senior research engineer in the Biochemical Process R&D group of the National Bioenergy Center at NREL. His primary role is the leader (Principal Investigator) for the Process Science of Enzymatic Hydrolysis subtask of the NREL Biomass Program. This work involves fundamental and applied research of the fluid mechanics, mass transfer, and reaction kinetics of biomass undergoing enzymatic hydrolysis in order to improve overall conversion yields and process economics.


Ph.D., Chemical Engineering, University of California at Davis, 2006
B.S., Chemical Engineering, Rensselaer Polytechnic Institute, 1999

Professional Experience

  • Senior Research Engineer, National Renewable Energy Laboratory, Golden, CO, 2009–present
  • Research Engineer, National Renewable Energy Laboratory, Golden, CO, 2007–2009
  • Process Development Engineer, Bayer Healthcare, Berkeley, CA, 2005–2007
  • Graduate Student Researcher, University of California, Davis, CA, 2001–2005
  • Process Engineering Associate, Biogen Idec (Biogen, Inc.), Cambridge, MA, 1999–2001

Research Interests

Jonathan Stickel has broad research interests in fluid mechanics, rheology, separation science, reaction engineering, mathematical modeling, and scientific computing. He is currently applying his expertise in these areas to the biochemical conversion of ligno-cellulosic biomass to liquid transportation fuels. During the conversion process, the ground biomass feedstock is degraded by chemical and biological catalysts in the presence of water to become a liquid slurry. The reacting biomass slurry is a heterogeneous, multi-phase material with complex physical and chemical properties. Well-established Newtonian fluid mechanics and solution reaction kinetics do not apply to these biomass slurries. Jonathan is performing fundamental and applied research to understand the fluid mechanics, mass transfer, and reaction kinetics of the biomass slurries in order to develop predictive modeling capabilities.

While performing research with the specific goal of improving the economics of biomass conversion, Jonathan develops mathematical models and numerical methods that sometimes have broad application. Recently, he implemented data smoothing by a regularization method in Octave and Python, as described in Computers and Chemical Engineering in 2010 (see full reference below).


  1. Griggs, A. J.; Stickel, J. J.; Lischeske, J. J. (2011). "A mechanistic model for enzymatic saccharification of cellulose using continuous distribution kinetics II: Cooperative enzymatic action, solution kinetics, and inhibition." Biotechnology and Bioengineering (109:3); pp. 676-685.

  2. Griggs, A. J.; Stickel, J. J.; Lischeske, J. J. (2011). "A mechanistic model for enzymatic saccharification of cellulose using continuous distribution kinetics I: Depolymerization by EGI and CBHI." Biotechnology and Bioengineering (109:3); pp. 665-675.

  3. Stickel, J. J.; Griggs, A. J. (2011). "Mathematical modeling of chain-end scission using continuous distribution kinetics." Chemical Engineering Science (68:1); pp. 656-659.

  4. Dibble, C. J.; Shatova, T. A.; Jorgenson, J. L.; Stickel, J. J. (2011). "Particle morphology characterization and manipulation in biomass slurries and the effect on rheological properties and enzymatic conversion." Biotechnology Progress (27:6); pp. 1751-1759.

  5. Zhu, Y. M.; Malten, M.; Torry-Smith, M.; McMillan, J. D.; Stickel, J. J. (2011). "Calculating sugar yields in high solids hydrolysis of biomass." Bioresource Technology (102:3); pp. 2897-2903.

  6. Weiss, N. D.; Stickel, J. J.; Wolfe, J. A.; Nguyen, Q. A. (2010). "A Simplified Method for the Measurement of Insoluble Solids in Pretreated Biomass Slurries." Applied Biochemistry and Biotechnology (162:4); pp. 975-987.

  7. Stickel, J. J. (2010). "Data Smoothing and Numerical Differentiation by a Regularization Method." Computers and Chemical Engineering (34:4); pp. 467-475.

  8. Roche, C. M.; Dibble, C. J.; Stickel, J. J. (2009). "Laboratory-Scale Method for Enzymatic Saccharification of Lignocellulosic Biomass at High-Solids Loadings." Biotechnology for Biofuels (2:28).

  9. Roche, C. M.; Dibble, C. J.; Knutsen, J. S.; Stickel, J. J.; Liberatore, M. W. (2009). "Particle Concentration and Yield Stress of Biomass Slurries during Enzymatic Hydrolysis at High-Solids Loadings." Biotechnology and Bioengineering (104:2); pp. 290-300.

  10. Stickel, J. J.; Knutsen, J. S.; Liberatore, M. W.; Luu, W.; Bousfield, D. W.; Klingenberg, D. J.; Scott, C. T.; Root, T. W.; Ehrhardt, M. R.; Monz, T. O. (2009). "Rheology Measurements of a Biomass Slurry: An Inter-Laboratory Study." Rheologica Acta (48:9); pp. 1005-1015.

  11. Stickel, J. J.; Phillips, R. J.; Powell, R. L. (2007). "Application of a Constitutive Model for Particulate Suspensions: Time-Dependent Viscometric Flows." Journal of Rheology (51:6); pp. 1271-1302.

  12. Stickel, J. J.; Phillips, R. J.; Powell, R. L. (2006). "A Constitutive Model for Microstructure and Total Stress in Particulate Suspensions." Journal of Rheology (50:4); pp. 379-413.

  13. Stickel, J. J.; Powell, R. L. (2005). "Fluid Mechanics and Rheology of Dense Suspensions." Annual Review of Fluid Mechanics (37); pp. 129-149.

  14. Stickel, J. J.; Fotopoulos, A. (2001). "Pressure-Flow Relationships for Packed Beds of Compressible Chromatography Media at Laboratory and Production Scale." Biotechnology Progress (17:4); pp. 744-751.

  15. Abatemarco, T.; Stickel, J. J.; Belfort, J.; Frank, B. P.; Ajayan, P. M.; Belfort, G. (1999). "Fractionation of multiwalled carbon nanotubes by cascade membrane microfiltration." Journal of Physical Chemistry B (103); pp. 3534-3538.

Contact Information

Jonathan J. Stickel, Ph.D.
Senior Research Engineer
National Bioenergy Center
National Renewable Energy Laboratory
1617 Cole Blvd., MS 3511
Golden, CO 80401
Phone: 303-384-6867
Fax: 303-384-6877