19 research outputs found
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Composition and Technical Basis for K Basin Settler Sludge Simulant for Inspection, Retrieval, and Pump Testing
This report provides the formulation and technical basis for a K Basin Settler Tank Sludge simulant that will be used by the K Basin Closure Project (KBC) to test and develop equipment/approaches for Settler Tank sludge level measurement and retrieval in a mock-up test system of the actual Settler Tanks. The sludge simulant may also be used to demonstrate that the TOYO high pressure positive displacement pump design (reversing valves and hollow balls) is suitable for transfer of Settler Tank sludge from the K West (KW) Basin to the Cold Vacuum Drying Facility (CVDF) (~500 ft). As requested the by the K Basins Sludge Treatment Project (STP) the simulant is comprised of non-radioactive (and non-uranium) constituents
Bio-oil Stabilization by Hydrogenation over Reduced Metal Catalysts at Low Temperatures
The
thermal and chemical instability of biomass fast pyrolysis oil (bio-oil)
presents significant problems when it is being converted to hydrocarbon
transportation fuels. Development of effective approaches for stabilizing
bio-oils is critical to the success of the biomass fast pyrolysis
and bio-oil upgrading technology. Catalytic hydrogenation to remove
reactive species in bio-oil has been considered as one of the most
efficient ways to stabilize bio-oil. This paper provides a fundamental
understanding of hydrogenation of actual bio-oils over a Ru/TiO<sub>2</sub> catalyst under conditions relevant to practical bio-oil hydrotreating
processes. The results indicated hydrogenation of various components
of the bio-oil, including sugars, aldehydes, ketones, alkenes, aromatics,
and carboxylic acids, over the Ru/TiO<sub>2</sub> catalyst and 120
to 160 °C. Hydrogenation of these species significantly changed
the chemical and physical properties of the bio-oil and overall improved
its thermal stability, especially by reducing the carbonyl content,
which represented the content of the most reactive species (i.e.,
sugar, aldehydes, and ketones). The change of content of each component
in response to increasing hydrogen additions suggests the following
bio-oil hydrogenation reaction sequence: sugar conversion to sugar
alcohols, followed by ketone and aldehyde conversion to alcohols,
followed by alkene and aromatic hydrogenation, and then followed by
carboxylic acid hydrogenation to alcohols. Sulfur poisoning of the
reduced Ru metal catalysts was significant during hydrogenation; however,
the inorganics at low concentrations had minimal impact at short times
on stream, indicating that sulfur poisoning was the primary deactivation
mode for the bio-oil hydrogenation catalyst. The knowledge gained
during this work will allow rational design of more effective catalysts
and processes for stabilizing and upgrading bio-oils
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Final Project Report Project 10749-4.2.2.1 2007-2009
This is the final report for the DOE Project 10749-4.2.2.1 for the FY2007 - FY2009 period. This report is non-proprietary, and will be submitted to DOE as a final project report. The report covers activities under the DOE Project inside CRADA 269 (Project 53231) as well as project activites outside of that CRADA (Project 56662). This is the final report that is summarized from the non-proprietary quarterlies submitted to DOE over the past 2.5 years, which in turn are summaries from the proprietary technical reporting to UOP
Final Project Report Project 10749-4.2.2.1 2007-2009
This is the final report for the DOE Project 10749-4.2.2.1 for the FY2007 - FY2009 period. This report is non-proprietary, and will be submitted to DOE as a final project report. The report covers activities under the DOE Project inside CRADA 269 (Project 53231) as well as project activites outside of that CRADA (Project 56662). This is the final report that is summarized from the non-proprietary quarterlies submitted to DOE over the past 2.5 years, which in turn are summaries from the proprietary technical reporting to UOP
Chemical Processing in High-Pressure Aqueous Environments. 6. Demonstration of Catalytic Gasification for Chemical Manufacturing Wastewater Cleanup in Industrial Plants
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Catalytic Hydrothermal Gasification of Lignin-Rich Biorefinery Residues and Algae Final Report
This report describes the results of the work performed by PNNL using feedstock materials provided by the National Renewable Energy Laboratory, KL Energy and Lignol lignocellulosic ethanol pilot plants. Test results with algae feedstocks provided by Genifuel, which provided in-kind cost share to the project, are also included. The work conducted during this project involved developing and demonstrating on the bench-scale process technology at PNNL for catalytic hydrothermal gasification of lignin-rich biorefinery residues and algae. A technoeconomic assessment evaluated the use of the technology for energy recovery in a lignocellulosic ethanol plant
Molybdenum Carbides, Active and <i>In Situ</i> Regenerable Catalysts in Hydroprocessing of Fast Pyrolysis Bio-Oil
This paper describes
properties of molybdenum carbides as a potential
catalyst for fast pyrolysis bio-oil hydroprocessing. Currently, high
catalyst cost, short catalyst lifetime, and lack of effective regeneration
methods are hampering the development of this otherwise attractive
renewable hydrocarbon technology. A series of metal-doped bulk Mo
carbides were synthesized, characterized, and evaluated in sequential
low-temperature stabilization and high-temperature deoxygenation of
a pine-derived bio-oil. During a typical 60 h run, Mo carbides were
capable of upgrading raw bio-oil to a level suitable for direct insertion
into the current hydrocarbon infrastructure with residual oxygen content
and total acid number of upgraded oils below 2 wt % and 0.01 mg KOH
g<sup>–1</sup>, respectively. The performance was shown to
be sensitive to the type of metal dopant, Ni-doped Mo carbides outperforming
Co-, Cu-, or Ca-doped counterparts; a higher Ni loading led to a superior
catalytic performance. No bulk oxidation or other significant structural
changes were observed. Besides the structural robustness, another
attractive property of Mo carbides was <i>in situ</i> regenerability.
The effectiveness of regeneration was demonstrated by successfully
carrying out four consecutive 60 h runs with a reductive decoking
between two adjacent runs. These results strongly suggest that Mo
carbides are a good catalyst candidate which could lead to a significant
cost reduction in hydroprocessing bio-oils. We highlight areas for
future research which will be needed to further understand carbide
structure–function relationships and help design practical
bio-oil upgrading catalysts based on Mo carbides
Sulfur-Tolerant Molybdenum Carbide Catalysts Enabling Low-Temperature Stabilization of Fast Pyrolysis Bio-oil
Low-temperature
hydrogenation of carbonyl compounds can greatly
improve the thermal stability of fast pyrolysis bio-oil, thereby enabling
long-term operation of upgrading reactors which generally require
high temperatures to achieve deep deoxygenation. The state-of-the-art
hydrogenation catalysts, precious metals such as ruthenium, although
effective in carbonyl hydrogenation, deactivate due to high sulfur
sensitivity. In the present work, we showed that molybdenum carbides
were active and sulfur-tolerant in low-temperature conversion of carbonyl
compounds. Furthermore, due to surface bifunctionality (i.e., both
metallic and acid sites present), carbides catalyzed both Cî—»O
bond hydrogenation and C–C coupling reactions. Combined, these
reactions transformed carbonyl compounds to more stable and higher
molecular weight oligomeric compounds while consuming less hydrogen
than pure hydrogenation. The carbides proved to be resistant to other
deactivation mechanisms including hydrothermal aging, oxidation, coking,
and leaching. These properties enabled carbides to achieve and maintain
good catalytic performance in both aqueous-phase furfural conversion
and real bio-oil stabilization in the presence of sulfur. This finding
strongly suggests that molybdenum carbides can provide a catalyst
solution necessary for the development of practical bio-oil stabilization
technology
Chemical Processing in High-Pressure Aqueous Environments. 9. Process Development for Catalytic Gasification of Algae Feedstocks
Author Correction: Multi-trait analysis of genome-wide association summary statistics using MTAG (Nature Genetics, (2018), 50, 2, (229-237), 10.1038/s41588-017-0009-4)
In the version of the paper initially published, no competing interests were declared. The ‘Competing interests’ statement should have stated that B.M.N. is on the Scientific Advisory Board of Deep Genomics. The error has been corrected in the HTML and PDF versions of the article