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Title: Effects of Torrefaction Temperature on Pyrolysis Vapor Products of Woody and Herbaceous Feedstocks

Abstract

A variety of hardwood, softwood, and herbaceous feedstocks (oak, southern yellow pine mix, loblolly pine, pinyon-juniper mix, and switchgrass) were each torrefied at 200, 250, and 300 °C. Each of the feedstocks was pyrolyzed and the resulting vapors were analyzed with a molecular beam mass spectrometer (py-MBMS). Compositional analysis was used to measure the total lignin content of three of the feedstocks (southern yellow pine, softwood; oak, hardwood; and switchgrass, herbaceous) before and after torrefaction at 300 °C, and large differences in the fraction of lignin lost during torrefaction were found between feedstocks, with oak having the largest decrease in lignin during torrefaction and switchgrass having the least. Finally, it is hypothesized that these differences in the thermal degradation are due to, in part, the different ratios of S, G, and H lignins in the feedstocks. Additionally, the torrefaction of kraft lignin was studied using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TGA-FTIR) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR).

Authors:
 [1];  [1];  [1];  [1]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
Publication Date:
Research Org.:
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)
OSTI Identifier:
1278316
Report Number(s):
NREL/JA-5100-65847
Journal ID: ISSN 0887-0624
Grant/Contract Number:
AC36-08GO28308
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Energy and Fuels
Additional Journal Information:
Journal Volume: 30; Journal Issue: 7; Journal ID: ISSN 0887-0624
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; torrefaction; biomass; pyroylsis; py-mbms

Citation Formats

Starace, Anne K., Evans, Robert J., Lee, David D., and Carpenter, Daniel L. Effects of Torrefaction Temperature on Pyrolysis Vapor Products of Woody and Herbaceous Feedstocks. United States: N. p., 2016. Web. doi:10.1021/acs.energyfuels.6b00267.
Starace, Anne K., Evans, Robert J., Lee, David D., & Carpenter, Daniel L. Effects of Torrefaction Temperature on Pyrolysis Vapor Products of Woody and Herbaceous Feedstocks. United States. doi:10.1021/acs.energyfuels.6b00267.
Starace, Anne K., Evans, Robert J., Lee, David D., and Carpenter, Daniel L. 2016. "Effects of Torrefaction Temperature on Pyrolysis Vapor Products of Woody and Herbaceous Feedstocks". United States. doi:10.1021/acs.energyfuels.6b00267. https://www.osti.gov/servlets/purl/1278316.
@article{osti_1278316,
title = {Effects of Torrefaction Temperature on Pyrolysis Vapor Products of Woody and Herbaceous Feedstocks},
author = {Starace, Anne K. and Evans, Robert J. and Lee, David D. and Carpenter, Daniel L.},
abstractNote = {A variety of hardwood, softwood, and herbaceous feedstocks (oak, southern yellow pine mix, loblolly pine, pinyon-juniper mix, and switchgrass) were each torrefied at 200, 250, and 300 °C. Each of the feedstocks was pyrolyzed and the resulting vapors were analyzed with a molecular beam mass spectrometer (py-MBMS). Compositional analysis was used to measure the total lignin content of three of the feedstocks (southern yellow pine, softwood; oak, hardwood; and switchgrass, herbaceous) before and after torrefaction at 300 °C, and large differences in the fraction of lignin lost during torrefaction were found between feedstocks, with oak having the largest decrease in lignin during torrefaction and switchgrass having the least. Finally, it is hypothesized that these differences in the thermal degradation are due to, in part, the different ratios of S, G, and H lignins in the feedstocks. Additionally, the torrefaction of kraft lignin was studied using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TGA-FTIR) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR).},
doi = {10.1021/acs.energyfuels.6b00267},
journal = {Energy and Fuels},
number = 7,
volume = 30,
place = {United States},
year = 2016,
month = 6
}

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Free Publicly Available Full Text
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Cited by: 2works
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