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Results for “Cu-Y”

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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7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Kinetic model development for single step ethanol to butene rich olefin process over Cu-Y/Beta catalysts

Here, this study presents the first intrinsic kinetic model for the single-step conversion of ethanol to butene-rich olefins over bifunctional Cu-Y/Beta catalysts, addressing a critical gap in the design and scale-up of Sustainable Aviation Fuel (SAF) processes. The reaction network comprises ten global steps involving dehydrogenation, aldol condensation, hydrogenation, and dehydration reactions, distributed across Cu and rare-earth (Y) active sites. The model incorporates dual-site functionality (Cu and Y site) and explicitly accounts for key intermediates such as crotonaldehyde and butanal. Reaction rates are formulated using Langmuir–Hinshelwood–Hougen–Watson (LHHW) kinetics. Kinetic parameters are extracted by fitting the model to lab-scale packed-bed reactor data across a wide range of temperatures and space velocities, demonstrating strong agreement in ethanol conversion and product selectivity. The reaction kinetics developed in this work provide a foundational basis for constructing reactor models that enable process optimization and scale-up of ethanol-to-jet fuel technologies.

Cu-Y/Beta catalyst↗
DOE OSTI2026

Understanding_the_deactivation_mechanisms_of_ethanol_conversion_over_Cu-Y_Beta_catalyst

Direct conversion of bioethanol to C₃⁺olefins is a promising pathway for sustainable aviation fuel (SAF) production, but catalyst deactivation limits long-term operation. The stability and deactivation mechanisms of multifunctional Cu–Y/Beta zeolite catalysts were investigated for ethanol-to-olefins conversion over 300 h time-on-stream in the presence of H2. Catalytic testing reveals progressive losses in ethanol conversion and C₃⁺ olefin selectivity accompanied by increased acetaldehyde formation. The catalyst testing studies correlate with a suite of characterizations of fresh, spent, and regenerated catalysts to identify the deactivation factors. The loss of Y Lewis acid sites is the primary deactivation element. Reversible acid site deactivation is caused by coke deposition, which blocks Y-derived Lewis acid sites responsible for aldol condensation, MPV reduction, and alcohol dehydration. Minor irreversible deactivation is observed and possibly results from hydrothermal dehydroxylation of Y–silanol interactions, resulting in permanent loss of Lewis acidity without zeolite framework degradation or Y aggregation. Cu sites undergo limited agglomeration into small nanoparticles but contribute insignificantly to catalyst deactivation, under the investigated time frame. Oxidative regeneration removes coke and redistributes Cu sites, leading to full recovery of the initial catalytic performance though the Y Lewis acid sites are unable to fully recover. These findings establish Lewis acid site degradation as the primary deactivation mechanism impacting long-term catalyst stability

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on YCu2 by Materials Project

YCu2 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Y is bonded in a 12-coordinate geometry to twelve equivalent Cu atoms. There are a spread of Y–Cu bond distances ranging from 2.94–3.11 Å. Cu is bonded in a 10-coordinate geometry to six equivalent Y and four equivalent Cu atoms. There are a spread of Cu–Cu bond distances ranging from 2.47–2.76 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YCu5 by Materials Project

Cu5Y crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Y is bonded in a 6-coordinate geometry to eighteen Cu atoms. There are six shorter (2.91 Å) and twelve longer (3.24 Å) Y–Cu bond lengths. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a 12-coordinate geometry to three equivalent Y and six equivalent Cu atoms. All Cu–Cu bond lengths are 2.50 Å. In the second Cu site, Cu is bonded to four equivalent Y and eight Cu atoms to form a mixture of face, edge, and corner-sharing CuY4Cu8 cuboctahedra. All Cu–Cu bond lengths are 2.52 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YCu by Materials Project

YCu is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Y is bonded in a body-centered cubic geometry to eight equivalent Cu atoms. All Y–Cu bond lengths are 3.01 Å. Cu is bonded in a body-centered cubic geometry to eight equivalent Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YCu by Materials Project

YCu crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Y is bonded in a 7-coordinate geometry to seven equivalent Cu atoms. There are a spread of Y–Cu bond distances ranging from 2.87–3.04 Å. Cu is bonded in a 9-coordinate geometry to seven equivalent Y and two equivalent Cu atoms. Both Cu–Cu bond lengths are 2.64 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YCu2 by Materials Project

YCu2 is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Y is bonded in a 12-coordinate geometry to twelve equivalent Cu atoms. All Y–Cu bond lengths are 3.09 Å. Cu is bonded to six equivalent Y and six equivalent Cu atoms to form a mixture of corner, edge, and face-sharing CuY6Cu6 cuboctahedra. All Cu–Cu bond lengths are 2.64 Å.

36 MATERIALS SCIENCE↗