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Title: Heterogeneous catalysis in complex, condensed reaction media

Abstract

Many reactions required for the upgrading of biomass into fuels and chemicals—hydrogenation, hydrodeoxygenation, hydrocracking—are ostensibly similar to those practiced in the upgrading of petroleum into fuels. But, repurposing hydroprocessing catalysts from refinery operations to treat bio-oil has proved to be unsatisfactory. New catalysts are needed because the composition of the biogenic reactants differs from that of petroleum-derived feedstocks (e.g. the low concentration of sulfur in cellulose-derived biomass precludes use of metal sulfide catalysts unless sulfur is added to the reaction stream). New processes are needed because bio-oils oligomerize rapidly, forming intractable coke and “gunk”, at temperatures so low that the desired upgrading reactions are impractically slow, and so low that the bio-oil upgrading must be handled as a condensed fluid. Ideally, the new catalysts and processes would exploit the properties of the multiple phases present in condensed bio-oil, notably the polarizability and structure of the fluid near a catalyst’s surface in the cybotactic region. The results of preliminary modeling of the cybotactic region of different catalyst surfaces in the hydrogenation of phenol suggest that Pd catalysts supported on hydrophilic surfaces are more active than catalysts based on lipophilic supports because the former serve to enhance the concentration of the phenolmore » in the vicinity of the Pd. The effect stems from thermodynamics, not the rate of mass transport. This work was supported by the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Bioenergy Technologies Office. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle.« less

Authors:
; ; ; ; ; ORCiD logo
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1372964
Report Number(s):
PNNL-SA-118180
Journal ID: ISSN 0920-5861; BM0101010
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Catalysis Today; Journal Volume: 289; Journal Issue: C
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Bio-oil; upgrading; solvophilicity; epiphilicity; cybotactic region

Citation Formats

Cantu, David C., Wang, Yang-Gang, Yoon, Yeohoon, Glezakou, Vassiliki-Alexandra, Rousseau, Roger, and Weber, Robert S. Heterogeneous catalysis in complex, condensed reaction media. United States: N. p., 2017. Web. doi:10.1016/j.cattod.2016.08.025.
Cantu, David C., Wang, Yang-Gang, Yoon, Yeohoon, Glezakou, Vassiliki-Alexandra, Rousseau, Roger, & Weber, Robert S. Heterogeneous catalysis in complex, condensed reaction media. United States. doi:10.1016/j.cattod.2016.08.025.
Cantu, David C., Wang, Yang-Gang, Yoon, Yeohoon, Glezakou, Vassiliki-Alexandra, Rousseau, Roger, and Weber, Robert S. Sat . "Heterogeneous catalysis in complex, condensed reaction media". United States. doi:10.1016/j.cattod.2016.08.025.
@article{osti_1372964,
title = {Heterogeneous catalysis in complex, condensed reaction media},
author = {Cantu, David C. and Wang, Yang-Gang and Yoon, Yeohoon and Glezakou, Vassiliki-Alexandra and Rousseau, Roger and Weber, Robert S.},
abstractNote = {Many reactions required for the upgrading of biomass into fuels and chemicals—hydrogenation, hydrodeoxygenation, hydrocracking—are ostensibly similar to those practiced in the upgrading of petroleum into fuels. But, repurposing hydroprocessing catalysts from refinery operations to treat bio-oil has proved to be unsatisfactory. New catalysts are needed because the composition of the biogenic reactants differs from that of petroleum-derived feedstocks (e.g. the low concentration of sulfur in cellulose-derived biomass precludes use of metal sulfide catalysts unless sulfur is added to the reaction stream). New processes are needed because bio-oils oligomerize rapidly, forming intractable coke and “gunk”, at temperatures so low that the desired upgrading reactions are impractically slow, and so low that the bio-oil upgrading must be handled as a condensed fluid. Ideally, the new catalysts and processes would exploit the properties of the multiple phases present in condensed bio-oil, notably the polarizability and structure of the fluid near a catalyst’s surface in the cybotactic region. The results of preliminary modeling of the cybotactic region of different catalyst surfaces in the hydrogenation of phenol suggest that Pd catalysts supported on hydrophilic surfaces are more active than catalysts based on lipophilic supports because the former serve to enhance the concentration of the phenol in the vicinity of the Pd. The effect stems from thermodynamics, not the rate of mass transport. This work was supported by the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Bioenergy Technologies Office. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle.},
doi = {10.1016/j.cattod.2016.08.025},
journal = {Catalysis Today},
number = C,
volume = 289,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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