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Mark Nimlos

Group Research Manager III-Physics | 303-384-7704
Orcid ID

Research Interests

Dr. Mark R. Nimlos is a principal scientist in the National Renewable Energy Laboratory's (NREL's) National Bioenergy Center (NBC). He has more than 25 years of experience in the design and management of complex, multiparty, biomass-related research programs and projects with a focus on thermochemical conversion research, reaction kinetics, computational modeling, photochemistry, and molecular spectroscopy. Nimlos has served as lead scientist and manager on numerous projects funded by the U.S. Department of Energy and by private industry. He has authored or co-authored more than 100 peer-reviewed scientific papers and/or book chapters.

  • Catalytic upgrading of pyrolysis vapors

  • Catalytic production of coproducts from biomass pyrolysis vapors

  • Combustion chemistry of biofuels

  • Mechanisms of biomass pyrolysis

Affiliated Research Programs

  • Catalytic Pyrolysis Science (PI)

  • Computational Pyrolysis Consortium (contributor)

  • Catalytic Upgrading of Pyrolysis Products (collaborator)

  • Catalytic Development/Testing: Deconstruction (collaborator)

  • Thermochemical Platform Analysis (collaborator)

  • Thermochemical Feedstocks Interface (collaborator)

Areas of Expertise

  • Chemical reaction energetics and kinetics

  • Biomass pyrolysis and gasification

  • Heterogeneous catalysis

    • Zeolite upgrading of biomass pyrolysis vapors

    • Photocatalytic oxidation

  • Molecular modeling

    • Quantum modeling in zeolites

    • Quantum modeling and kinetic modeling of reaction

    • Molecular dynamics modeling

  • Photochemistry

  • Molecular spectroscopy


  • Ph.D., Chemical Physics, University of Colorado at Boulder, 1986

  • B.S., Chemistry, University of Massachusetts, 1981

Professional Experience

  • Section Lead, NREL, NBC, Biomass Molecular Sciences, 2007–present

  • Staff Scientist, NREL (Solar Energy Research Institute), NBC, 19902007

  • Postdoctoral Researcher, Solar Energy Research Institute, 19891990


  1. "Cellobiohydrolase I enzymes," U.S. Patent No. 8,637,293 (2014)

Featured Publications

Biomass Pyrolysis and Gasification

  1. "Catalytic Fast Pyrolysis of Biomass: The Reactions of Water and Aromatic Intermediates Produces Phenols," Green Chemistry (2015)

  2. "Real-Time Monitoring of the Deactivation of HZSM-5 During Upgrading of Pine Pyrolysis Vapors," Green Chemistry (2014)

  3. "Upgrading Biomass Pyrolysis Vapors over βZeolites: Role of Silica-to-Alumina Ratio," Green Chemistry (2014)

  4. "Molybdenum Incorporated Mesoporous Silica Catalyst for Production of Biofuels and Value-Added Chemicals via Catalytic Fast Pyrolysis," Green Chemistry (2015)

  5. "Application of an Fourier Transform-Infrared Imaging Tool for Measuring Temperature or Reaction Profiles in Pyrolyzed Wood," Energy & Fuels (2011)

  6. "Biomass Pyrolysis and Gasification of Varying Particle Sizes in a Fluidized-Bed Reactor," Energy & Fuels (2011)

  7. "Pilot-Scale Gasification of Corn Stover, Switchgrass, Wheat Straw, and Wood: 1. Parametric Study and Comparison with Literature," Industrial & Engineering Chemistry Research (2010)

  8. "Elucidation of Biomass Pyrolysis Products Using a Laminar Entrained Flow Reactor and Char Particle Imaging," Energy & Fuels (2011)

  9. "Real-Time and Post-Reaction Microscopic Structural Analysis of Biomass Undergoing Pyrolysis," Energy & Fuels (2009)

Decomposition of Model Compounds

  1. "The Thermal Decomposition of the Benzyl Radical in a Heated Micro-Reactor. I. Experimental Findings," Journal of Chemical Physics (2015)

  2. "Biomass Pyrolysis: Thermal Decomposition Mechanisms of Furfural and Benzaldehyde," Journal of Chemical Physics (2013)

  3. "Polarized Matrix Infrared Spectra of Cyclopentadienone: Observations, Calculations, and Assignment for an Important Intermediate in Combustion and Biomass Pyrolysis," Journal of Physical Chemistry A (2014)

  4. "Direct Detection of Products from the Pyrolysis of 2-Phenethyl Phenyl Ether," Journal of Physical Chemistry A (2011)

  5. "Unimolecular Thermal Decomposition of Phenol and d5-Phenol: Direct Observation of Cyclopentadiene Formation via Cyclohexadienone," Journal of Chemical Physics (2012)

Computational Modeling

  1. "Ethanol Dehydration in HZSM-5 Studied by Density Functional Theory: Evidence for a Concerted Process," Journal of Physical Chemistry A (2015)

  2. "Biomass Particle Models with Realistic Morphology and Resolved Microstructure for Simulations of Intraparticle Transport Phenomena," Energy & Fuels (2015)

  3. "Bimolecular Decomposition Pathways for Carboxylic Acids of Relevance to Biofuels," Journal of Physical Chemistry A (2015)

  4. "Comparison of Unimolecular Decomposition Pathways for Carboxylic Acids of Relevance to Biofuels," Journal of Physical Chemistry A (2014)

  5. "Binding Preferences, Surface Attachment, Diffusivity, and Orientation of a Family 1 Carbohydrate-binding Module on Cellulose," Journal of Biological Chemistry (2012)

  6. "Mechanisms of Glycerol Dehydration," Journal of Physical Chemistry A (2006)

Biomass Preteatment

  1. "Investigation of Xylose Reversion Reactions in Dilute Acid Pretreatment," Energy & Fuels (2013)

  2. "Glucose Reversion Reaction Kinetics," Journal of Agricultural and Food Chemistry (2009)


  1. "Intense, Hyperthermal Source of Organic Radicals for Matrix-Isolation Spectroscopy," Review of Scientific Instruments (2003)

  2. "Propargyl Radical: Ab Initio Anharmonic Modes and the Polarized Infrared Absorption Spectra of Matrix-Isolated HCCCH2," Journal of Physical Chemistry A (2005)

  3. "Polarized Infrared Absorption Spectra of Matrix-Isolated Allyl Radicals," Journal of Physical Chemistry A (2001)

  4. "Polarized Infrared Absorption Spectrum of Matrix-Isolated Methylperoxyl Radicals, CH3OO X̃ 2A,'' Journal of Physical Chemistry A (2002)

  5. "The Pyrolysis of Anisole (C6H5OCH3) Using a Hyperthermal Nozzle," Fuel (2001)

  6. "The Infrared Spectrum of the Matrix-Isolated Phenyl Radical," Journal of the American Chemical Society (2001)

View all NREL Publications for Mark R. Nimlos.