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Energy and Environment Directorate

Richard Hallen

Richard Hallen

Pacific Northwest National Laboratory
PO Box 999
Richland, WA 99352
(509) 375-6919


Rich Hallen has been at the lab for 30 years working as a research chemist in the area of chemical reactions and separation of components in complex mixtures. Areas of past research have included synthetic fuel production, gas separations, homogeneous and heterogeneous catalysis, industrial chemical synthesis, and waste treatment. More recent research has focused on the development and deployment of new chemical synthesis processes based upon alternate feedstocks. The research efforts are developing new materials from bio-based renewable resources and new processes for production of fuels and chemicals from renewable resources, primarily agricultural based feedstocks. One key area of research has involved catalytic transformation of fermentation derived compounds. Current efforts are focused on the conversion of biomass resources to high volume industrial chemicals and production of renewable jet and diesel fuels. Currently, serving as Team Lead for the Fuel Conversion Area of the NAABB consortium and is the PNNL project manager for the NABC consortium.

Research Interests

  • Developing new materials from bio-based renewable resources.
  • Developing new processes for production of fuels and chemicals from renewable resources (primarily agricultural based feedstocks).
  • Catalytic transformation of fermentation-derived compounds.
  • Conversion of biomass resources to high volume industrial chemicals and production of renewable jet and diesel fuels.

Education and Credentials

  • M.S., Chemistry, Oregon State UniversityB.S., Mathematics and Physical Sciences, Lewis-Clark State College

Awards and Recognitions

  • R & D 100 Award. "Carbohydrate Conversion Process." Walkup, P. C., C. A. Rohrmann, D.E. Eakin, R. T. Hallen, and G. L. Roberts. 1991.
  • Federal Laboratory Consortium Award for Excellence in Technology Transfer. "Conversion of Fermentable Carbohydrates to Acrylate Esters." Walkup, P. C., C. A. Rohrmann, D.E. Eakin, and R. T. Hallen. 1990.

PNNL Patents

PNNL Publications


  • Butcher MG, PA Meyer, RT Hallen, KO Albrecht, CK Clayton, E Polikarpov, KG Rappe, SB Jones, and JK Magnuson. 2018. "Fungal Metabolites as Precursors to Renewable Transportation Fuels." Fuel 215:123-141.  doi:10.1016/j.fuel.2017.10.052
  • Jarvis JM, JM Billing, YE Corilo, AJ Schmidt, RT Hallen, and T Schaub. 2018. "FT-ICR MS Analysis of Pine-Algal HTL Biocrude Blends." Fuel 216:341-348.  doi:10.1016/j.fuel.2017.12.016
  • Marrone PA, DC Elliott, JM Billing, RT Hallen, TR Hart, P Kadota, JC Moeller, MA Randel, and AJ Schmidt. 2018. "Bench-Scale Evaluation of Hydrothermal Processing Technology for Conversion of Wastewater Solids to Fuels." Water Environment Research 90(4):329-342. 


  • Jarvis JM, JM Billing, RT Hallen, AJ Schmidt, and T Schaub. 2017. "Hydrothermal Liquefaction Biocrude Compositions Compared to Petroleum Crude and Shale Oil." Energy and Fuels 31(3):2896-2906.  doi:10.1021/acs.energyfuels.6b03022
  • Marrone PA, DC Elliott, JM Billing, RT Hallen, TR Hart, P Kadota, JC Moeller, MA Randel, and AJ Schmidt. 2017. "Bench-Scale Evaluation of the Genifuel Hydrothermal Processing Technology for Wastewater Solids." In Proceedings of the Water Environment Federation, (WEFTEC 2017), September 30 - October 4, 2017, Chicago, Illinois, pp. 3032-3061.  Water Environment Federation, ALEXANDRIA, VA.  doi:10.2175/193864717822157702
  • Olarte MV, AB Padmaperuma, J Ferrell, ED Christensen, RT Hallen, RB Lucke, SD Burton, TL Lemmon, MS Swita, G Fioroni, DC Elliott, and C Drennan. 2017. "Characterization of Upgraded Fast Pyrolysis Oak Oil Distillate Fractions from Sulfided and Non-Sulfided Catalytic Hydrotreating." Fuel 202:620-630.  doi:10.1016/j.fuel.2017.03.051
  • Snowden-Swan LJ, Y Zhu, MD Bearden, TE Seiple, SB Jones, AJ Schmidt, JM Billing, RT Hallen, TR Hart, J Liu, KO Albrecht, SP Fox, GD Maupin, and DC Elliott. 2017. Conceptual Biorefinery Design and Research Targeted for 2022: Hydrothermal Liquefacation Processing of Wet Waste to FuelsPNNL-27186, Pacific Northwest National Laboratory, Richland, WA. 



  • Andersen A, SM Kathmann, MA Lilga, KO Albrecht, RT Hallen, and D Mei. 2014. "Effects of Potassium Doping on CO Hydrogenation Over MoS2 Catalysts: A First-Principles Investigation." Catalysis Communications 52:92-97.  doi:10.1016/j.catcom.2014.02.011
  • Jones SB, Y Zhu, DB Anderson, RT Hallen, DC Elliott, AJ Schmidt, KO Albrecht, TR Hart, MG Butcher, C Drennan, LJ Snowden-Swan, R Davis, and C Kinchin. 2014. Process Design and Economics for the Conversion of Algal Biomass to Hydrocarbons: Whole Algae Hydrothermal Liquefaction and UpgradingPNNL-23227, Pacific Northwest National Laboratory, Richland, WA. 
  • Jones SB, Y Zhu, LJ Snowden-Swan, D Anderson, RT Hallen, AJ Schmidt, KO Albrecht, and DC Elliott. 2014. Whole Algae Hydrothermal Liquefaction: 2014 State of TechnologyPNNL-23867, Pacific Northwest National Laboratory, Richland, WA. 
  • Sudasinghe N, B Dungan, P Lammers, KO Albrecht, DC Elliott, RT Hallen, and T Schaub. 2014. "High resolution FT-ICR mass spectral analysis of bio-oil and residual water soluble organics produced by hydrothermal liquefaction of the marine microalga Nannochloropsis salina." Fuel 119:47-56.  doi:10.1016/j.fuel.2013.11.019
  • Sudasinghe N, JR Cort, RT Hallen, MV Olarte, AJ Schmidt, and T Schaub. 2014. "Hydrothermal Liquefaction Oil and Hydrotreated Product from Pine Feedstock Characterized by Heteronuclear Two-Dimensional NMR Spectroscopy and FT-ICR Mass Spectrometry." Fuel 137:60-69.  doi:10.1016/j.fuel.2014.07.069


  • Zhu Y, KO Albrecht, DC Elliott, RT Hallen, and SB Jones. 2013. "Development of Hydrothermal Liquefaction and Upgrading Technologies for Lipid-Extracted Algae Conversion to Liquid Fuels." Algal Research 2(4):455-464.  doi:10.1016/j.algal.2013.07.003
  • Dagle RA, VMC Lebarbier, JA Lizarazo Adarme, DL King, Y Zhu, MJ Gray, SB Jones, MJ Biddy, RT Hallen, Y Wang, JF White, JE Holladay, and DR Palo. 2013. Single-Step Syngas-to-Distillates (S2D) Synthesis via Methanol and Dimethyl Ether Intermediates: Final ReportPNNL-22984, Pacific Northwest National Laboratory, Richland, WA. 
  • Elliott DC, TR Hart, AJ Schmidt, GG Neuenschwander, LJ Rotness, Jr, MV Olarte, AH Zacher, KO Albrecht, RT Hallen, and JE Holladay. 2013. "Process Development for Hydrothermal Liquefaction of Algae Feedstocks in a Continuous-Flow Reactor ." Algal Research 2(4):445-454. 



  • Albrecht KO, and RT Hallen. 2011. A Brief Literature Overview of Various Routes to Biorenewable Fuels from Lipids for the National Alliance for Advanced Biofuels and Bio-products (NAABB) ConsortiumPNNL-20279, Pacific Northwest National Laboratory, Richland, WA. 
  • Billing JM, RC Daniel, RT Hallen, PP Schonewill, RW Shimskey, and RA Peterson. 2011. "Chemical cleaning of porous stainless steel cross-flow filter elements for nuclear waste applications." In American Filtration and Separations Society Annual Meeting, May 10-12, 2011, Lousiville, Kentucky.  American Filtration & Separations Society, Kingwood, TX. 
  • Andersen A, SM Kathmann, MA Lilga, KO Albrecht, RT Hallen, and D Mei. 2011. "Adsorption of Potassium on the MoS2(100) Surface: A First-Principles Investigation." Journal of Physical Chemistry C 115(18):9025-9040.  doi:10.1021/jp110069r


  • Lilga MA, RT Hallen, and MJ Gray. 2010. "Production of Oxidized Derivatives of 5-Hydroxymethylfurfural (HMF)." Topics in Catalysis 53(15-18):1264-1269. 



  • Geeting JGH, RT Hallen, and RA Peterson. 2006. "Ultrafilter Conditions for High Level Waste Sludge Processing." Separation Science and Technology 41(11):2313-2324. 


  • Geeting JGH, and RT Hallen. 2005. "Filtration, Washing, and Caustic Leaching of Hanford Tank AZ-101 Sludge." Separation Science and Technology 40(1-3):1-15. 
  • Geeting JGH, RT Hallen, and RA Peterson. 2005. "Optimization of Ultrafilter Feed Conditions Using Classical Filtration Models." Journal of Membrane Science 265(1-2):137-141.  doi:10.1016/j.memsci.2005.05.008
  • Hallen RT, JGH Geeting, MA Lilga, TR Hart, and FV Hoopes. 2005. "Assessment of the Mechanisms for Sr-90 and Tru Removal from Complexant-Containing Tank Wastes at Hanford." Separation Science and Technology 40(1-3):171-183. 



  • Gauger AM, and RT Hallen. 2001. "Individual Reactions of Permanganate & Various Reductants." Journal of Undergraduate Research 1:54. 


  • Fryxell GE, J Liu, TA Hauser, Z Nie, KF Ferris, SV Mattigod, M Gong, and RT Hallen. 1999. "Design and Synthesis of Selective Mesoporous Anion Types ." Chemistry of Materials 11(8):2148-2154. 
  • Rassat SD, JH Sukamto, RJ Orth, MA Lilga, and RT Hallen. 1999. "Development of Electrically Switched Ion Exchange Process for Selective Ion Separations." Separation and Purification Technology 15(3):207-222. 


  • Bowman LE, NH Reade, RT Hallen, and A Butenhoff. 1998. "Advances in Carbon Dioxide Based Sizing and Desizing." Textile Research Journal 68(10):732-738. 

Energy and Environment

Core Research Areas