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Spivey, James J.

Publications and source records attributed to Spivey, James J..

7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Low temperature catalytic conversion of CH 4 , CO 2 , and C 2 H 4 to value-added C 3 oxygenates and olefins via C 1 -C 2 coupling on Pd-Au/CeO 2

The catalytic conversion of CH 4 and CO 2 in the presence of more reactive co-reactants C 2 H 4 and O 2 on Pd-Au/CeO 2 is achieved at 200 °C and elevated pressures. Propene and acetone were produced from the catalyzed reaction of CH 4 +C 2 H 4 +O 2 ; addition of CO 2 to the reactant stream produced methyl acetate (MAc) but it significantly reduced the C-selectivities of propene and acetone. DRIFTS experiments confirmed the formation of methoxy species from CH 4 +CO 2 at 200 °C, which is an intermediate in the formation of MAc. Here, control experiments with blanks, and with CeO 2 did not show any propene, acetone, or MAc products. The complete oxidation of C 2 H 4 was avoided; the catalyst is stable, and reactant conversions and product yields were sustained for the observed 1200 min time-on-stream, indicating that there is little or no carbon deposition and sintering. This direct coupling of CH 4 and C 2 H 4 intermediates to higher carbon-number products at 200 °C is significant.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Metal organic framework-mediated synthesis of potassium-promoted cobalt-based catalysts for higher oxygenates synthesis

Syngas to higher oxygenates conversion was carried out on a series of potassium-promoted cobalt-based catalysts. Catalysts with different potassium composition were prepared by metal organic framework-mediated synthesis, which is the calcination of the ZIF-67 metal organic framework (MOF). Cobalt skeleton structure that originated from the MOF is preserved after the calcination. The calcined catalysts consist of Co 3 O 4 nanoparticles and surface carbon. The catalysts were reduced by H 2 /He prior to the reaction. CO hydrogenation was carried out at various temperatures (270 °C, 300 °C and 325 °C) and at 40 bar, with H 2 /CO = 1/1. The formation of methane and higher hydrocarbons is suppressed by potassium, and cobalt carbide is formed from metallic cobalt during the reaction. Thus, the K-promoted cobalt based catalyst synthesized by the MOF-mediated synthesis shows higher selectivity to ethanol, acetaldehyde and higher oxygenates, even at high temperatures.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Method of CO and/or CO.sub.2 hydrogenation to higher hydrocarbons using doped mixed-metal oxides

A method of hydrogenation utilizing a reactant gas mixture comprising a carbon oxide and a hydrogen agent, and a hydrogenation catalyst comprising a mixed-metal oxide containing metal sites supported and/or incorporated into the lattice. The mixed-metal oxide comprises a pyrochlore, a brownmillerite, or mixtures thereof doped at the A-site or the B-site. The metal site may comprise a deposited metal, where the deposited metal is a transition metal, an alkali metal, an alkaline earth metal, or mixtures thereof. Contact between the carbon oxide, hydrogen agent, and hydrogenation catalyst under appropriate conditions of temperature, pressure and gas flow rate generate a hydrogenation reaction and produce a hydrogenated product made up of carbon from the carbon oxide and some portion of the hydrogen agent. The carbon oxide may be CO, CO.sub.2, or mixtures thereof and the hydrogen agent may be H.sub.2. In a particular embodiment, the hydrogenated product comprises olefins, paraffins, or mixtures thereof.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Final Technical Report

The research summarized here has the goal of developing a fundamental understanding of how catalysts work. These materials are demonstrably essential to our daily life, from the cars we drive to the clothes we wear. Our Center advances the science behind how we prepare, analyze, and describe catalysts. This has been identified by one of the documents guiding Federal research objectives (Directing Matter and Energy: Five Challenges for Science and the Imagination): “Major challenges in heterogeneous catalysis are to more clearly define the nature of the active sites, to engineer at the molecular level catalysis with designed properties in three dimensions, and to create new catalysts for new transformations.” This directly addresses this objective.

10 SYNTHETIC FUELS↗