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Energy and Environment Directorate

Mariefel Olarte

Mariefel Olarte

Pacific Northwest National Laboratory
PO Box 999
Richland, WA 99352
(509) 375-2200


Dr. Mariefel V. Olarte joined PNNL in 2011 after completing her graduate studies from the Georgia Institute of Technology with a doctorate degree in Chemical Engineering under Prof. Christopher W. Jones and Prof. Pradeep K. Agrawal. Her research is focused on catalytic upgrading of bio-oils to produce hydrocarbons and the analysis of the reactant and product streams. This involves working with teams at PNNL and external collaborators to develop catalyst, process and analytical methods. She has experience in the catalytic conversion of biomass to renewable fuels and chemicals and had worked on aqueous phase reforming of pine, biomass fractionation (aqueous- and ionic liquid-phase acid hydrolysis and lignin depolymerization) and catalytic upgrading of phenolic compounds. Since joining PNNL, she is mainly involved in the catalytic upgrading of pyrolysis oil and characterization of biomass-derived streams. Aside from these, she has also worked on catalytic hydrothermal gasification and hydrothermal liquefaction technologies, oxidative lignin depolymerization as well as in the commissioning a demonstration scale hydrotreater (20L) and distillation systems. Recently, she has interest in machine learning applications in chemistry and chemical processes.

Research Interests

  • Catalytic upgrading of biomass for renewable fuel and chemical production
  • Catalyst synthesis and characterization
  • Analysis of biomass-derived liquid products

Education and Credentials

  • Ph.D. Chemical Engineering, Georgia Institute of Technology
  • M.S. Paper Science and Engineering, Georgia Institute of Technology
  • B.S. Chemical Engineering, University of the Philippines Los BaƱos

PNNL Publications


  • Denson M.D., E. Terrell, P. Kostetskyy, L.J. Broadbelt, M.V. Olarte, and M. Garcia-Perez. 2023. "Theoretical Insights on the Fragmentation of Cellulosic Oligomers to form Hydroxyacetone and Hydroxyacetaldehyde." Energy and Fuels 37, no. 18:13997-14005. PNNL-SA-181688. doi:10.1021/acs.energyfuels.3c01924
  • Denson M.D., E. Terrell, P. Kostetskyy, M.V. Olarte, L.J. Broadbelt, and M. Garcia-Perez. 2023. "Elucidation of Structure and Physical Properties of Pyrolytic Sugar Oligomers derived from Cellulose Depolymerization/Dehydration Reactions: A Density Functional Theory Study." Energy and Fuels 37, no. 11:7834-7847. PNNL-SA-184731. doi:10.1021/acs.energyfuels.3c00641
  • Doll C.G., A.E. Plymale, M.J. O'Hara, C.J. Thompson, A.R. Cooper, H. Wang, and M.V. Olarte. 2023. "Demonstration of low-level biogenic fuel content using quench curve and direct liquid scintillation counting (LSC) methods." Fuel 334, no. Part 1:Art. No. 126468. PNNL-SA-173920. doi:10.1016/j.fuel.2022.126468
  • Eswaran S., M.V. Olarte, R.J. Rallo Moya, L.N. Marrlett, J.A. Harper, M.S. Anderson, and E.M. Shapiro, et al. 2023. "HT Model: Using the Molecular Transformer for predicting hydrotreating reactions." Energy and Fuels 37, no. 19:14922-14935. PNNL-SA-186589. doi:10.1021/acs.energyfuels.3c02224
  • Manrique R., E. Terrell, P. Kostetskyy, F. Chejne, M.V. Olarte, L.J. Broadbelt, and M. Garcia-Perez. 2023. "Elucidating Biomass-Derived Pyrolytic Lignin Structures from Demethylation Reactions Through Density Functional Theory Calculations." Energy and Fuels 37, no. 7:5189-5205. PNNL-SA-181824. doi:10.1021/acs.energyfuels.2c04292
  • Pires A.P., M. Garcia-Perez, M.V. Olarte, W.R. Kew, A.J. Schmidt, K. Zemaitis, and M.D. Denson, et al. 2023. "Comparison of the Chemical Composition of Liquids from the Pyrolysis and Hydrothermal Liquefaction of Lignocellulosic Materials." Energy and Fuels 37, no. 10:7221-7236. PNNL-SA-174549. doi:10.1021/acs.energyfuels.2c03239


  • Doll C.G., A.E. Plymale, C.J. Thompson, M.J. O'Hara, and M.V. Olarte. 2022. Determination of Biogenic Content by 14C in fuels using Liquid Scintillation Analysis Laboratory Analytical Procedure (LAP). PNNL-32719. Richland, WA: Pacific Northwest National Laboratory. Determination of Biogenic Content by 14C in fuels using Liquid Scintillation Analysis Laboratory Analytical Procedure (LAP)
  • Sulejmanovic D., J. Keiser, Y. Su, M.D. Kass, J. Ferrell, M.V. Olarte, and J.E. Wade Iv, et al. 2022. "Effect of Carboxylic Acids on Corrosion of Type 410 Stainless Steel in Pyrolysis Bio-Oil." Sustainability 14, no. 18:Art. No. 11743. PNNL-SA-177580. doi:10.3390/su141811743


  • Doll C.G., A.E. Plymale, A. Cooper, I.V. Kutnyakov, M.S. Swita, T.L. Lemmon, and M.V. Olarte, et al. 2021. "Determination of low-level biogenic gasoline, jet fuel, and diesel in blends using the direct liquid scintillation counting method for 14C content." Fuel 291. PNNL-SA-157538. doi:10.1016/j.fuel.2020.120084
  • Lackey H.E., H.A. Colburn, M.V. Olarte, T.L. Lemmon, H.M. Felmy, S.A. Bryan, and A.M. Lines. 2021. "On-line Raman measurement of radiation-enhanced reaction of cellobiose with hydrogen peroxide." ACS Omega 6. PNNL-SA-165646. doi:10.1021/acsomega.1c04852
  • Ma R., U. Sanyal, M.V. Olarte, H.M. Job, M.S. Swita, S.B. Jones, and P.A. Meyer, et al. 2021. "Role of peracetic acid on the disruption of lignin packing structure and its consequence on lignin depolymerisation." Green Chemistry 23, no. 21:8468-8479. PNNL-SA-159270. doi:10.1039/D1GC02300D
  • Thorson M.R., D.M. Santosa, R.T. Hallen, I.V. Kutnyakov, M.V. Olarte, M.D. Flake, and G.G. Neuenschwander, et al. 2021. "SCALEABLE HYDROTREATING OF HTL BIOCRUDE TO PRODUCE FUEL BLENDSTOCKS." Energy and Fuels 35, no. 14:11346-11352. PNNL-SA-160510. doi:10.1021/acs.energyfuels.1c00956


  • Colburn H.A., H.E. Lackey, M.V. Olarte, H.M. Felmy, A.M. Lines, and S.A. Bryan. 2020. Radiation-Induced Catalysis of Chemical Reactions. PNNL-30788. Richland, WA: Pacific Northwest National Laboratory. Radiation-Induced Catalysis of Chemical Reactions
  • Wei H., M.V. Olarte, and G. Goh. 2020. "Multiple-objective Reinforcement Learning for Inverse Design and Identification." In Proceedings of the 34th AAAI Conference on Artificial Intelligence (AAAI-2020), February 7-12, 2020, New York. Palo Alto, California:AAAI Press. PNNL-SA-147355.


  • Albrecht K.O., M.V. Olarte, and H. Wang. 2019. "Upgrading Fast Pyrolysis Liquids." In Thermochemical Processing of Biomass: Conversion into Fuels, Chemicals and Power, 2nd Edition, edited by R.C. Brown. 207-255. Hoboken, New Jersey:John Wiley & Sons Ltd. PNNL-SA-130792. doi:10.1002/9781119417637.ch7
  • Han Y., M. Gholizadeh, C. Tran, S. Kaliaguine, C. Li, M.V. Olarte, and M. Garcia-Perez. 2019. "Hydrotreatment of pyrolysis bio-oil: A review." Fuel Processing Technology 195. PNNL-SA-142929. doi:10.1016/j.fuproc.2019.106140
  • Olarte M.V., K.O. Albrecht, J.T. Bays, E. Polikarpov, B. Maddi, J.C. Linehan, and M.J. O'Hagan, et al. 2019. "Autoignition and Select Properties of Low Sample Volume Thermochemical Mixtures from Renewable Sources." Fuel 238. PNNL-SA-134830. doi:10.1016/j.fuel.2018.10.115
  • Zacher A.H., D.C. Elliott, M.V. Olarte, H. Wang, S.B. Jones, and P.A. Meyer. 2019. "Technology Advancements in Hydroprocessing of Bio-oils." Biomass & Bioenergy 125. PNNL-SA-138596. doi:10.1016/j.biombioe.2019.04.015


  • Brittain A.D., N.J. Chrisandina, R.E. Cooper, M. Buchanan, J.R. Cort, M.V. Olarte, and C. Sievers. 2018. "Quenching of Reactive Intermediates During Mechanochemical Depolymerization of Lignin." Catalysis Today 302. PNNL-SA-120623. doi:10.1016/j.cattod.2017.04.066
  • Lewis, Sr. S.A., R.M. Connatser, M.V. Olarte, and J. Keiser. 2018. "Determining Aromatic and Aliphatic Carboxylic Acids in Biomass-Derived Oil Samples Using 2,4-Dinitrophenylhydrazine and Liquid Chromatography-Electrospray Injection-Mass Spectrometry/Mass Spectrometry." Biomass & Bioenergy 108. PNNL-SA-131788. doi:10.1016/j.biombioe.2017.10.043
  • Olarte M.V., J.J. Bravo-Suarez, H. Wang, and F. Tao. 2018. "Preface." Catalysis Today 302. PNNL-SA-138643. doi:10.1016/j.cattod.2017.11.015
  • Wei H., M.V. Olarte, and G.B. Goh. 2018. "Multiple-objective Reinforcement Learning for Inverse Design and Identification." In Proceedings of the 32nd Conference on Neural Information Processing Systems (NeurlPS 2018), December 3-8, 2018, Montreal, Canada, edited by S. Bengio, et al. Red Hook, New York:Curran Associates, Inc. PNNL-SA-139575.


  • Eckstein S., P.H. Hintermeier, M.V. Olarte, Y. Liu, E. Barath, and J.A. Lercher. 2017. "Elementary steps and reaction pathways in the aqueous phase alkylation of phenol with ethanol." Journal of Catalysis 352. PNNL-SA-125449. doi:10.1016/j.jcat.2017.06.002
  • Hintermeier P.H., S. Eckstein, D. Mei, M.V. Olarte, D.M. Camaioni, E. Barath, and J.A. Lercher. 2017. "Hydronium-Ion-Catalyzed Elimination Pathways of Substituted Cyclohexanols in Zeolite H-ZSM5." ACS Catalysis 7, no. 11:7822-7829. PNNL-SA-131496. doi:10.1021/acscatal.7b01582
  • Olarte M.V., A.B. Padmaperuma, J. Ferrell, E.D. Christensen, R.T. Hallen, R.B. Lucke, and S.D. Burton, et al. 2017. "Characterization of Upgraded Fast Pyrolysis Oak Oil Distillate Fractions from Sulfided and Non-Sulfided Catalytic Hydrotreating." Fuel 202. PNNL-SA-119855. doi:10.1016/j.fuel.2017.03.051
  • Prodinger S., H. Shi, S. Eckstein, J.Z. Hu, M.V. Olarte, D.M. Camaioni, and M.A. Derewinski, et al. 2017. "Stability of Zeolites in Aqueous Phase Reactions." Chemistry of Materials 29, no. 17:7255-7262. PNNL-SA-123271. doi:10.1021/acs.chemmater.7b01847
  • Stankovikj F., A. McDonald, G.L. Helms, M.V. Olarte, and M. Garcia-Perez. 2017. "Characterization of the Water-Soluble Fraction of Woody Biomass Pyrolysis Oils." Energy and Fuels 31, no. 2:1650-1664. PNNL-SA-121870. doi:10.1021/acs.energyfuels.6b02950
  • Stankovikj F., C. Tran, S. Kaliaguine, M.V. Olarte, and M. Garcia-Perez. 2017. "Evolution of Functional Groups during Pyrolysis Oil Upgrading." Energy and Fuels 31, no. 8:8300-8316. PNNL-SA-125910. doi:10.1021/acs.energyfuels.7b01251


  • Agblevor F., D.C. Elliott, D.M. Santosa, M.V. Olarte, S.D. Burton, M.S. Swita, and S. Beis, et al. 2016. "Red Mud Catalytic Pyrolysis of Pinyon Juniper and Single-Stage Hydotreatment of Oils." Energy and Fuels 30, no. 10:7947-7958. PNNL-SA-122742. doi:10.1021/acs.energyfuels.6b00925
  • Choi J., A.H. Zacher, H. Wang, M.V. Olarte, B.L. Armstrong, H. Meyer, and I. Soykal, et al. 2016. "Molybdenum carbides, active and in situ regenerable catalysts in hydroprocessing of fast pyrolysis bio-oil." Green Chemistry 30, no. 6:5016-5026. PNNL-SA-116507. doi:10.1021/acs.energyfuels.6b00937
  • Ferrell J., M.V. Olarte, E.D. Christensen, A.B. Padmaperuma, R.M. Connatser, F. Stankovikj, and D. Meier, et al. 2016. "Standardization of Chemical Analytical Techniques for Pyrolysis Bio-oil: History, Challenges, and Current Status of Methods." Biofuels, Bioproducts & Biorefining 10, no. 5:496-507. PNNL-SA-123869. doi:10.1002/bbb.1661
  • Olarte M.V., A.H. Zacher, A.B. Padmaperuma, S.D. Burton, H.M. Job, T.L. Lemmon, and M.S. Swita, et al. 2016. "Stabilization of Softwood-Derived Pyrolysis Oils for Continuous Bio-oil Hydroprocessing." Topics in Catalysis 59, no. 1:55-64. PNNL-SA-111135. doi:10.1007/s11244-015-0505-7
  • Shangguan J., M.V. Olarte, and Y. Chin. 2016. "Mechanistic Insights on C-O and C-C Bond Activation and Hydrogen Insertion during Acetic Acid Hydrogenation Catalyzed by Ruthenium Clusters in Aqueous Medium." Journal of Catalysis 340. PNNL-SA-115243. doi:10.1016/j.jcat.2016.04.024
  • Wang H., S. Lee, M.V. Olarte, and A.H. Zacher. 2016. "Bio-oil stabilization by hydrogenation over reduced metal catalysts at low temperatures." ACS Sustainable Chemistry & Engineering 4, no. 10:5533-5545. PNNL-SA-118919. doi:10.1021/acssuschemeng.6b01270


  • Weber R.S., M.V. Olarte, and H. Wang. 2015. "Modeling the Kinetics of Deactivation of Catalysts during the Upgrading of Bio-Oil." Energy and Fuels 29, no. 1:273-277. PNNL-SA-106604. doi:10.1021/ef502483t


  • Sudasinghe N., J.R. Cort, R.T. Hallen, M.V. Olarte, A.J. 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. PNNL-SA-102800. doi:10.1016/j.fuel.2014.07.069
  • Zacher A.H., D.C. Elliott, M.V. Olarte, D.M. Santosa, F. Preto, and K. Iisa. 2014. "Pyrolysis of Woody Residue Feedstocks: Upgrading of Bio-Oils from Mountain-Pine-Beetle-Killed Trees and Hog Fuel." Energy and Fuels 28, no. 12:7510-7516. PNNL-SA-104767. doi:10.1021/ef5017945
  • Zacher A.H., M.V. Olarte, D.M. Santosa, D.C. Elliott, and S.B. Jones. 2014. "A Review and Perspective of Recent Bio-Oil Hydrotreating Research." Green Chemistry 16, no. 2:885-896. PNNL-SA-96894. doi:10.1039/c3gc41782d


  • Elliott D.C., T.R. Hart, A.J. Schmidt, G.G. Neuenschwander, L.J. Rotness, M.V. Olarte, and A.H. Zacher, et al. 2013. "Process Development for Hydrothermal Liquefaction of Algae Feedstocks in a Continuous-Flow Reactor." Algal Research 2, no. 4:445-454. PNNL-SA-96121.


  • Elliott D.C., T.R. Hart, G.G. Neuenschwander, L.J. Rotness, M.V. Olarte, A.H. Zacher, and Y. Solantausta. 2012. "Catalytic Hydroprocessing of Fast Pyrolysis Bio-oil from Pine Sawdust." Energy and Fuels 26, no. 6:3891-3896. PNNL-SA-86336. doi:10.1021/ef3004587
  • Elliott D.C., T.R. Hart, G.G. Neuenschwander, L.J. Rotness, M.V. Olarte, and A.H. Zacher. 2012. "Chemical Processing in High-Pressure Aqueous Environments. 9. Process Development for Catalytic Gasification of Algae Feedstocks." Industrial and Engineering Chemistry Research 51, no. 33:10768-10777. PNNL-SA-87140. doi:10.1021/ie300933w

Energy and Environment

Core Research Areas