skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Review of NMR characterization of pyrolysis oils

Abstract

Here, pyrolysis of renewable biomass has been developed as a method to produce green fuels and chemicals in response to energy security concerns as well as to alleviate environmental issues incurred with fossil fuel usage. However, pyrolysis oils still have limited commercial application, mainly because unprocessed oils cannot be readily blended with current petroleum-based transportation fuels. To better understand these challenges, researchers have applied diverse characterization techniques in the development of bio-oil studies. In particular, nuclear magnetic resonance (NMR) is a key spectroscopic characterization method through analysis of bio-oil components. This review highlights the NMR strategies for pyrolysis oil characterization and critically discusses the applications of 1H, 13C, 31P, 19F, and two-dimensional (2-D NMR) analyses such as heteronuclear single quantum correlation (HSQC) in representative pyrolysis oil studies.

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Univ. of Tennessee, Knoxville, TN (United States)
  2. Southeast Univ., Nanjing (People's Republic of China)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  4. Auburn Univ., Auburn, AL (United States)
  5. Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee Institute of Agriculture, Knoxville, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1324221
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Energy and Fuels
Additional Journal Information:
Journal Name: Energy and Fuels; Journal ID: ISSN 0887-0624
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS

Citation Formats

Hao, Naijia, Ben, Haoxi, Yoo, Chang Geun, Adhikari, Sushil, and Ragauskas, Arthur J. Review of NMR characterization of pyrolysis oils. United States: N. p., 2016. Web. doi:10.1021/acs.energyfuels.6b01002.
Hao, Naijia, Ben, Haoxi, Yoo, Chang Geun, Adhikari, Sushil, & Ragauskas, Arthur J. Review of NMR characterization of pyrolysis oils. United States. doi:10.1021/acs.energyfuels.6b01002.
Hao, Naijia, Ben, Haoxi, Yoo, Chang Geun, Adhikari, Sushil, and Ragauskas, Arthur J. 2016. "Review of NMR characterization of pyrolysis oils". United States. doi:10.1021/acs.energyfuels.6b01002. https://www.osti.gov/servlets/purl/1324221.
@article{osti_1324221,
title = {Review of NMR characterization of pyrolysis oils},
author = {Hao, Naijia and Ben, Haoxi and Yoo, Chang Geun and Adhikari, Sushil and Ragauskas, Arthur J.},
abstractNote = {Here, pyrolysis of renewable biomass has been developed as a method to produce green fuels and chemicals in response to energy security concerns as well as to alleviate environmental issues incurred with fossil fuel usage. However, pyrolysis oils still have limited commercial application, mainly because unprocessed oils cannot be readily blended with current petroleum-based transportation fuels. To better understand these challenges, researchers have applied diverse characterization techniques in the development of bio-oil studies. In particular, nuclear magnetic resonance (NMR) is a key spectroscopic characterization method through analysis of bio-oil components. This review highlights the NMR strategies for pyrolysis oil characterization and critically discusses the applications of 1H, 13C, 31P, 19F, and two-dimensional (2-D NMR) analyses such as heteronuclear single quantum correlation (HSQC) in representative pyrolysis oil studies.},
doi = {10.1021/acs.energyfuels.6b01002},
journal = {Energy and Fuels},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 8
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 3works
Citation information provided by
Web of Science

Save / Share:
  • Renewable transportation fuels from biomass have the potential to substantially reduce greenhouse gas emissions and diversify global fuel supplies. Thermal conversion by fast pyrolysis converts up to 75% of the starting plant material (and its energy content) to a bio-oil intermediate suitable for upgrading to motor fuel. Woody biomass, by far the most widely-used and researched material, is generally preferred in thermochemical processes due to its low ash content and high quality bio-oil produced. However, the availability and cost of biomass resources, e.g. forest residues, agricultural residues, or dedicated energy crops, vary greatly by region and will be key determinatesmore » in the overall economic feasibility of a pyrolysis-to-fuel process. Formulation or blending of various feedstocks, combined with thermal and/or chemical pretreatment, could facilitate a consistent, high-volume, lower-cost biomass supply to an emerging biofuels industry. However, the impact of biomass type and pretreatment conditions on bio-oil yield and quality, and the potential process implications, are not well understood. This literature review summarizes the current state of knowledge regarding the effect of feedstock and pretreatments on the yield, product distribution, and upgradability of bio-oil.« less
  • Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. As such, carbonyl content has previously been used as a method of tracking bio-oil aging and condensation reactions with less variability than viscosity measurements. Given the importance of carbonyls in bio-oils, accurate analytical methods for their quantification are very important for the bio-oil community. Potentiometric titration methods based on carbonyl oximation have long been used for the determination of carbonyl content in pyrolysis bio-oils. Here in this study, we present a modification of the traditional carbonyl oximation procedures that results inmore » less reaction time, smaller sample size, higher precision, and more accurate carbonyl determinations. Some compounds such as carbohydrates are not measured by the traditional method (modified Nicolaides method), resulting in low estimations of the carbonyl content. Furthermore, we have shown that reaction completion for the traditional method can take up to 300 hours. The new method presented here (the modified Faix method) reduces the reaction time to 2 hours, uses triethanolamine (TEA) in the place of pyridine, and requires a smaller sample size for the analysis. Carbonyl contents determined using this new method are consistently higher than when using the traditional titration methods.« less
  • The effluents of pulp bleaching are the main problem of wastewater disposal faced by the pulp industry because of their non-biodegradability. Today the demand for quality discharges requires better methods than conventional biological processes. The changes recently proposed to the federal regulations for controlling discharges from pulp and paper industry operations in Canada have required many operations to install secondary biological effluent treatment process. Such treatment often produce sludges that must be removed from the system and disposed of routinely, usually daily or weekly. This paper describes pyrolytic oils obtained from sludges from the paper and pulp industry.
  • Quantitative 13C NMR analysis of model catalytic fast pyrolysis (CFP) oils following literature procedures showed poor agreement for aromatic hydrocarbons between NMR measured concentrations and actual composition. Furthermore, modifying integration regions based on DEPT analysis for aromatic carbons resulted in better agreement. Solvent effects were also investigated for hydrotreated CFP oil.