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Title: Standardization of chemical analytical techniques for pyrolysis bio-oil: history, challenges, and current status of methods

Here, we discuss the standardization of analytical techniques for pyrolysis bio-oils, including the current status of methods, and our opinions on future directions. First, the history of past standardization efforts is summarized, and both successful and unsuccessful validation of analytical techniques highlighted. The majority of analytical standardization studies to-date has tested only physical characterization techniques. In this paper, we present results from an international round robin on the validation of chemical characterization techniques for bio-oils. Techniques tested included acid number, carbonyl titrations using two different methods (one at room temperature and one at 80 °C), 31P NMR for determination of hydroxyl groups, and a quantitative gas chromatography–mass spectrometry (GC-MS) method. Both carbonyl titration and acid number methods have yielded acceptable inter-laboratory variabilities. 31P NMR produced acceptable results for aliphatic and phenolic hydroxyl groups, but not for carboxylic hydroxyl groups. As shown in previous round robins, GC-MS results were more variable. Reliable chemical characterization of bio-oils will enable upgrading research and allow for detailed comparisons of bio-oils produced at different facilities. Reliable analytics are also needed to enable an emerging bioenergy industry, as processing facilities often have different analytical needs and capabilities than research facilities. We feel that correlations in reliablemore » characterizations of bio-oils will help strike a balance between research and industry, and will ultimately help to -determine metrics for bio-oil quality. Lastly, the standardization of additional analytical methods is needed, particularly for upgraded bio-oils.« less
 [1] ;  [2] ;  [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  4. Washington State Univ., Pullman, WA (United States)
  5. Thunen Inst. of Wood Research (TI), Hamburg (Germany)
  6. VTT Technical Research Centre of Finland Ltd (VTT), Espoo (Finland)
Publication Date:
Report Number(s):
Journal ID: ISSN 1932-104X; BM0102060; CEBM007
Grant/Contract Number:
AC05-00OR22725; AC36-08-GO28308; AC06-76RLO1830; AC36-08GO28308; AC06-76RL01830
Accepted Manuscript
Journal Name:
Biofuels, Bioproducts & Biorefining
Additional Journal Information:
Journal Volume: 10; Journal Issue: 5; Journal ID: ISSN 1932-104X
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fuels, Engines and Emissions Research Center (FEERC); National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Bioenergy Technologies Office (EE-3B)
Country of Publication:
United States
09 BIOMASS FUELS; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; bio-oil; analysis; analytical; titration; round robin; pyrolysis
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1320384