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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 757 records · Page 42
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Processing of SOFC Anodes for Enhanced Intermediate Temperature Catalytic Activity at High Fuel Utilization (Final Report)

The overall objective was to infiltrate anodes with nanoparticle catalysts so that anode catalytic performance can be improved as anode operation temperature is reduced from 800°C to intermediate temperatures of 700°C and 600°C and as anode fuel utilization is increased. The addition of nickel nanoparticle catalysts into the anode improves performance by providing additional triple phase boundaries (TPBs), increasing the density of electrochemical reaction sites. To achieve this goal, both liquid phase and vapor phase methods for depositing nickel nanoparticles in the anode active layer, the region of the anode near the electrolyte where the electrochemical reaction occurs. It is imperative that nanoparticles are stable against coarsening during long-term operation, so the mechanisms and kinetics of nanoparticle stability during cell operation will be investigated. Finally, priority is given to processes that are scalable and easily transferable to industry, leveraging existing Ni-YSZ cermet anode technology. Utilizing nickel nanoparticles at different temperatures has different considerations that will be addressed. At the upper end of the intermediate temperature range (800°C), it is important that performance improvement is maintained over long periods by mitigating the instability of nanoparticles. At the middle of the temperature range (700°C), it is important that performance improvement is maintained at high fuel utilizations. At the lower end of the temperature range (600°C), where the performance of cells is poor due to increased resistances, it is important to improve anode performance by significantly increasing the electrochemical reaction site density, while nanoparticle durability is less of an issue. Finally, the objective was to explore mixed ionic and electronic (MIEC) nanoparticle catalysts like GDC to see if 2-phase boundaries can be created to increase the electrochemical reactions at the anode.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2022

Selective Catalytic Oxidations: Opportunities and Challenges for the Selective Conversion of Renewable Resources

The goal of this DOE-funded project was to investigate the fundamental science related to selective catalytic oxidation reactions for converting renewable polyhydroxylated bio-feedstocks into new classes of value-added chemicals. The focus was on selective oxidation catalysis, specifically the mechanisms and origin of chemoselectivity for the selective Pd-catalyzed aerobic oxidations of biomass-derived polyols and carbohydrates.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Catalytic Selective Oxidations with Porous Transition Metal Oxides

This final report covers work done concerning oxidation catalysis over the past year. There are three major areas involving synthesis, characterization, and catalysis. The synthetic focus has been on porous metal oxides. Full characterization of these systems using a variety of methods has been done using ex-situ, in situ, and operando conditions. A major goal of the work has been to study the mechanisms of catalytic oxidations including identification of reaction intermediates. Specific applications besides oxidations concern electrocatalytic water splitting, water harvesting, CO 2 capture, and environmental catalysis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Customization for Current Market Applications of the Carbon Nanotubes Produced by PNNL’s Regenerable Catalytic Pyrolysis (ReCaP) for Scaled Hydrogen Production

Here, we demonstrated the Regenerative Catalytic Pyrolysis (ReCaP) process that generates carbon dioxide-free hydrogen (CO 2 -free H 2 ) from inexpensive and domestically abundant natural gas (NG), while simultaneously producing H 2 at net production cost of $1.0/kg through the sale of valuable carbon nanotube (CNT) co-product. The specific goal of this project is to 1) scale up the production of CNT, 2) correlate the properties of the CNT with the reaction conditions, 3) perform a techno-economic analysis to obtain minimum selling price of H 2 and CNT, and 4) identify industrial partners interested in the CNT co-product.

03 NATURAL GAS↗
DOE OSTI2023

Plasma-Assisted Catalytic Conversion of CO 2 and Propane to Propylene and CO

Ethylene and propylene are critical pillars of the petrochemical and plastics industry. The current industrial route for producing these olefins, which is via steam cracking process, is extremely endothermic and highly CO 2 -intensive. In this work, Susteon, in partnership with the North Carolina State University (NCSU), New Castle University (NU), and SoCalGas, has investigate catalytic materials and process designs to produce propylene from propane by utilizing CO 2 as a soft oxidant in the presence of low temperature dielectric barrier discharge plasma. This route integrates the effect of catalysis and the presence of a plasma environment to intensify the production of the important three carbon olefin from propane at a lower temperature and near atmospheric pressure. This CO 2 oxidative dehydrogenation (CO 2 -ODH) process coproduces CO, which is a valuable by-product, critical for the petrochemical sector. Through this work, Susteon and the team have made significant progress in developing catalysts and gaining insights on the plasma-assisted CO 2 -ODH process.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2023

Catalytic upgrading of ethanol to C8+ distillate range ethers via Guerbet coupling and etherification

In this presentation we describe the catalytic approaches for conversion of ethanol into diesel fuel ethers. This involves first alcohol oligomerization, followed by acid-catalyzed dehydration. As we will show in this presentation, ethanol can be converted to higher linear and α-branched alcohols by C-C coupling reactions (ethanol oligomerization) as well as to high molecular weight esters by C-O coupling reactions with Cu/MgxAlOy (CuHT) catalysts. Alcohols may be converted to ethers via bimolecular dehydration in a subsequent step. We have identified more than 160 number of species in the products including alcohols, esters, aldehydes, ketones, and olefins. Alcohols range from C4 to C10. Both alcohols and esters follow a Schulz-Flory chain growth model. We show the relationship between the catalyst properties (BET surface area, acid and base site count and Cu loading and synthesis method) and the performance in the reactions. We also show that physical mixtures of CuHT and HT can have similar product selectivity of low loading CuHT catalysts. The selectivity towards diesel fuel precursor compounds (hereafter ‘DFPC’) increased with conversion until reaching a plateau at high ethanol conversion (~70%). Alcohol selectivity follows a Schultz-Flory distribution at all studied conversions, and that adsorbed ethanol-derived species may undergo surface oligomerization into 1-butanol and higher alcohols before desorbing in a chain-growth mechanism. Zeolite catalysts convert the C4+ alcohols into C8+ ethers in both batch and continuous flow reactors. Selectivities of up to 80% to C8+ ethers at around 70% conversion using a single pass continuous flow system are achieved. The final product feedstocks obtained from etherification have been used in technoeconomic (TEA) and lifecycle analysis (LCA), which indicate a reduction in greenhouse gas (GHG) emissions of 50% relative to conventional diesel and diesel fuel prices that are lower than biodiesel. These final feedstocks are undergoing engine testing to elucidate the physiochemical properties and compare well to diesel #2 ASTM standards.

Huber, George↗
DOE OSTI2024

Process Intensification by One-Step, Plasma-Assisted Catalytic Synthesis of Liquid Chemicals from Light Hydrocarbons

In this project, we present a plasma-assisted, catalytic process that can handle variations in production rates and gas compositions of producing wells and reliably converts the hydrocarbons to gas phase olefins, high molecular weight alkanes, and liquid chemicals. The low-temperature plasma serves as a reactive chemical environment that activates and converts the light hydrocarbons to these valuable products. We present results from the integration of a catalyst into the low-temperature plasma zone to improve reaction efficiency and product selectivity. We show that the gas composition, bulk gas temperature, and input power of the plasma, with and without catalysts, influence the production rates of liquids from natural gas feeds.

03 NATURAL GAS↗
DOE OSTI2024

Catalytic Approaches to C–O Activation in Biorenewable Feedstocks

The carbon present in biomass (the largest renewable source on the planet) continues to tempt us as a possible replacement for the carbon we currently obtain from fossil fuels. As we have recently reviewed, the challenges of extracting chemically useful feedstocks from biorenewables, and, especially, cellulosics, is largely under-developed relative to the maturity of the technologies for deriving industrially useful chemicals from petroleum. This ultimately boils down to problems in functionalization catalysis (for oil) versus defunctionalization (for cellulosics). The technology gap for achieving the selective defunctionalization of cellulosic feedstocks is much larger than it is for petroleum functionalization. This assessment suggests that the problem is not that bio-renewable feedstocks are fundamentally flawed from an economic and chemical sustainability perspective, but that we lack the technologies for deoxygenating cellulosic to more valuable chemicals. Bozell and Petersen have argued that integrated biorefineries will require a suite of products for viability (in analogy to an integrated petroleum refinery). These products will range from low-value high-volume energy related products (i.e. fuels) to high-value low-volume compounds focused on specialty markets and pharmaceuticals. The latter, although less impactful in terms of volume, is a critical economic component of the future integrated biorefinery. Our review was stimulated by their assessment of the state of the biorefinery and focused on the available chemistries for achieving low-volume high-value outcomes. To help fill this technology gap, we seek new catalytic technologies for synthesizing high-value chemicals from cellulosics and take the view that the inherent chirality of C 6 O 6 feedstocks will provide valuable materials for specialty and pharmaceutical applications, but only if one can achieve site-selective reactions that don’t denude the stereochemistry inherent to the sugars. Eliminative methods are less desirable as this deoxygenation scheme removes multiple stereocenters. The research plan outlined herein seeks methods for site-selective deoxygenation reactions that lead to high value specialty/pharma products.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Electrolyzer Integrated Modular Nano-Array Monolithic Catalytic Reactors

The project objective is to design and develop a new class of electrolyzer-integrated, modular, nanostructure array (nano-array) monolithic catalytic reactors for high-flux, robust and selective methanol synthesis. The modular reactor features metal oxide nano-array grown on an additively-manufactured channeled honeycomb monolith made of ceramic or metals; this low-pressure carbon dioxide hydrogenation reactor is fueled with hydrogen from a low-temperature water electrolyzer having reduced platinum group metal (PGM) content. Through these nanostructured monolithic reactors, methanol synthesis is enabled with cost-effective hydrogenation reactions under low-temperature (<200°C) and low-pressure (<10 atm) conditions, thus significantly reducing the energy demand of the entire process.

08 HYDROGEN↗
DOE OSTI2024

Microwave-Assisted Catalytic Conversion of Tar Using Iron Catalyst Doped with Ni/La/Ce

The goal of this research is to study the microwave-assisted catalytic dry reforming of toluene using Fe/Al2O3 as a catalyst in the presence of various dopants such as Ni/La/Ce in a conventional fixed-bed reactor. Initial studies show that both CO2 and toluene conversion can be achieved up to 85% at 500 °C. Higher toluene conversion and syngas production was achieved under microwave conditions compared to conventional thermal conditions. The pre and post-reaction catalyst characterizations were performed using X-ray diffraction analysis (XRD) and thermogravimetric analysis (TGA). The tar analysis was performed using gas chromatography–mass spectrometry (GC-MS). The product gas mainly consisted of H2, CO, methane, propane, ethylene, and ethane along with small amounts of benzene, and naphthalene. The production of benzene indicates the hydrodemethylation (HDM) process of toluene, which requires hydrogen to initiate the reaction. The reaction pathway was proposed based on the observed product gas.

Linge Gowda, Anitha Shankara↗
DOE OSTI2024

Microwave-Assisted Syngas Cleanup: Catalytic Reforming of Gasifier Tar Using a Low-Cost Iron Catalyst

In this work, we studied the microwave-assisted catalytic dry reforming of toluene using Fe/Al2O3 as a catalyst, under CO2 at different reaction temperatures. The toluene reforming reaction was conducted using microwave and conventional thermal reactors. The results showed that under microwave irradiation, a higher CO2 and toluene conversions, as well as better hydrogen yield can be observed compared to conventional toluene reforming at the same reaction temperature. The catalyst stability test was also investigated. Three reaction pathways were observed during microwave reaction: the toluene decomposition produces initial hydrogen and carbon deposit on the catalyst; the formation of methane and benzene suggests toluene hydrodemethylation that took place secondly; toluene hydrogenolysis forms light alkanes such as methane, and through reforming reaction under CO2 to syngas. The pre- and post-reaction catalyst characterizations were done to reveal the structure-reactivity relationships and compare the catalyst structure after microwave and conventional reactions.

Bai, Xinwei↗
DOE OSTI2024

Off-line Tests of the DM1200 Thermal Catalytic Oxidation (TCO) Unit (Final Report)

The River Protection Project-Waste Treatment Plant (RPP-WTP) Low-Activity Waste (LAW) and High-Level Waste (HLW) feed streams are listed for a variety of hazardous organic compounds. The permitting basis for the WTP systems may necessitate the demonstration of minimum Destruction/Removal Efficiencies (DREs) of such species from any released emissions of up to 99.99%. Results from a previous study on the fate of hazardous organics in the melter itself indicated, not only that DREs for selected test compounds approached 99.99% only at extreme melter conditions, but also that organic compounds not originally present in the feed were actually produced in the melter, In order to ensure that the required DREs for hazardous organics are met, Thermal Catalytic Oxidation (TCO) units were therefore added to both the HLW and LAW off-gas treatment systems, The extent to which these species can be destroyed or removed in the TCO units is therefore an important issue in the design and permitting of the LAW and HLW off-gas treatment systems. A further consideration is that it would be desirable, if possible, to be able to achieve all of the required DRE across the TCO alone. If that is not the case, the DRE would be distributed across several unit operations, which may then become subject to additional operational constraints that may reduce process flexibility. Compliance with the DRE requirements on the basis of the TCO unit alone is also an approach that lends itself to periodic confirmation during operations, since the TCO is located at the back-end of the off-gas treatment system where radioactivity levels are lowest.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Slashing Platinum Group Metals (PGM) in Catalytic Converters: An Atoms-to-Autos Approach

Platinum group metals (PGMs) are used in three-way catalysts (TWCs) for stoichiometric gasoline engine vehicles to simultaneously convert carbon monoxide, hydrocarbons, and nitrogen oxides into nitrogen, carbon dioxide and water. For US light duty gasoline vehicles, about 3-8 grams of PGMs are used in each catalytic converter system and the PGM loading is expected to increase for future vehicles, driven by increasingly stringent emissions standards, potentially lower engine exhaust temperatures, and higher emission control system durability requirements. The technical necessity for the current high PGM loadings is largely driven by: 1) poor atomic efficiency (or metal dispersion) of PGMs on catalyst supports with the current synthesis approaches, and 2) severe deactivation of unstable PGM nanoparticles in high temperature engine exhaust. Therefore, the project team will develop catalyst technologies that not only maximize the PGM atom efficiency and intrinsic activity in the fresh state, but also maintain the benefits during aging with extended exposure in engine exhaust.

36 MATERIALS SCIENCE↗
DOE OSTI2024

De novo Materials Design of Catalytic Surface Motifs for Water-Gas-Shift (Final Progress Report DOE Grant DE-SC0019281)

This project was aimed at developing innovative theoretical methods and models to understand essential catalysis-relevant issues such as CO 2 conversion, fuel cells, and lithium batteries. Through collaborations with experimentalists, we strive to develop new quantum and machine learning methods for the understanding of surface and interfacial chemistry that can empower the design of energy and sustainability systems. Overall, our work under this grant brings cross-disciplinary insights into catalytic materials, microenvironments, and other conditions, which can serve to provide design rules for the next generation of catalysts.

25 ENERGY STORAGE↗
DOE OSTI2022

Plasma Assisted Catalytic Conversion of Carbon Dioxide (CO2) and Propane to Propylene and Carbon Monoxide (CO)

Presented at the NETL Project Review Meetings in 2022, the presentation summary includes the following status updates: -Feasibility of the CO2-ODH reaction with plasma demonstrated at much lower temperatures than conventional processes -Presence of CO2 enhances propane conversion in the plasma reactor -Ce doped, 5 wt.%/CexZr1-xO2 catalyst demonstrated enhanced selectivity and stability for propylene production via CO2-ODH process under thermal conditions -Comprehensive characterization coupled with designed catalytic experiments identified Cr3+ as the active site CO2-ODH proceeds via dehydrogenation route -Coke formation, which causes catalyst deactivation, inhibited by both Ce and CO2

Zhou, S. James↗
DOE OSTI2025

Catalytic Activation of Pyran Ethers in Self-Solvating Saccharides with Alkaline Earth Metals (Final Report)

Catalytic activation of cellulose ethers occurs via hydroxyl-stabilized cleavage of inter-monomer glycosidic bonds. Cooperativity between two hydroxyl groups lowers the ether cleavage transition state necessary to break apart long carbohydrate chains to initiate small molecule formation as fuel precursors. Metals existing with lignocellulosic materials including alkaline earth metals (Ca 2+ , Mg 2+ ) or alkali (Na + , K + ) also can catalyze ether scission cooperatively. By bonding with carbohydrate hydroxyl groups, a metal cation disrupt the hydrogen bonding network and free carbohydrate functional groups to react; a second metal cation stabilizes the carbohydrate ether transition state and enhances the rate of polymer scission. In this work, we expanded our initial understanding of metal-catalyzed glycoside ether scission. Within polysaccharides such as cellulose, two ether groups exist: one between monomers (glycosidic linkages) and one within a pyran ring. The hydroxyl-group hydrogen bonding network and bound metal ions form low energy binding states that interact with both ether oxygens simultaneously. Based on this interaction, our primary hypothesis was that the competition between stabilizing the two ether scission transition states determines the extent of the major pathways. Metals that disrupt the hydrogen bonding network of the C6 of sugars and stabilize the glycosidic ether promote transglycosylation to levoglucosan; in contrast, metals that stabilize the pyran ether oxygen promote sugar ring fragmentation to furans such as furfural. Varying characteristics of metal cation catalysts and configurations of bound polysaccharide chains dictate the relative rates of ether scission.

09 BIOMASS FUELS↗
DOE OSTI2025

Microwave-Assisted Catalytic Gasification of Various Biomass with Mixed Plastic Wastes for H2-Rich Syngas Production

Co-gasification of plastics mixture with biomass has shown synergistic effects in Microwave (MW) reactor resulting in higher H2-rich syngas yield and reduced char/tar. This study investigates a microwave-assisted catalytic gasification of variable feedstock such as various biomass blended with mixed plastics waste using Fe-based catalyst to produce H2 rich syngas as a primary product.

catalysis, biomass gasification↗