Thermally-activated catalysis on CuNi nanoparticles

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00131581" target="_blank" >RIV/00216224:14310/23:00131581 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Thermally-activated catalysis on CuNi nanoparticles

Popis výsledku v původním jazyce

The CuNi nanoparticles (NPs) were prepared by solvothermal synthesis. The nanoparticles were characterised by electron microscopy, X-ray powder diffraction, thermal analysis (DSC), and other methods. The CuNi NPs were deposited on superfine unreactive silica supports. After purification, the nanostructured mesoporous CuNi(NPs)/SiO2 powder was obtained. The catalyst was compressed into tablets, which were activated by hydrogen involving gas (20 vol.% H2 in N2) at 300C. Tablets containing CuNi NPs with different Cu/Ni ratios were prepared. The model catalytic reaction of ethanol non-oxidative dehydrogenation to acetaldehyde was studied in the gaseous phase. The absolute ethanol (liquid) reaction feed was introduced through a syringe pump in a preheated stream on N2 (ethanol vaporization occurs). Catalytic tests were carried out in a fixed-bed stainless steel reactor. The experimental temperature range was 200 - 350C. We observe the highest ethanol conversions with acetaldehyde selectivity of about 80% and ethanol conversion of about 10% for catalytic samples involving a Cu/Ni molar ratio equal to 2.30. The highest conversion was obtained at 220C, but the catalyst deactivation upon a time was observed. The characterization of the catalyst after the use was done. The electron microscopy confirmed that the microstructure remained mesoporous and free of oxides. Oxide-free structure and nanometer-size particles of CuNi were also confirmed by X-ray powder diffraction analysis. The leading cause of catalyst deactivation is not oxidation but coke forming. The results were compared with a similar experiment on copper NPs.

Název v anglickém jazyce

Thermally-activated catalysis on CuNi nanoparticles

Popis výsledku anglicky

The CuNi nanoparticles (NPs) were prepared by solvothermal synthesis. The nanoparticles were characterised by electron microscopy, X-ray powder diffraction, thermal analysis (DSC), and other methods. The CuNi NPs were deposited on superfine unreactive silica supports. After purification, the nanostructured mesoporous CuNi(NPs)/SiO2 powder was obtained. The catalyst was compressed into tablets, which were activated by hydrogen involving gas (20 vol.% H2 in N2) at 300C. Tablets containing CuNi NPs with different Cu/Ni ratios were prepared. The model catalytic reaction of ethanol non-oxidative dehydrogenation to acetaldehyde was studied in the gaseous phase. The absolute ethanol (liquid) reaction feed was introduced through a syringe pump in a preheated stream on N2 (ethanol vaporization occurs). Catalytic tests were carried out in a fixed-bed stainless steel reactor. The experimental temperature range was 200 - 350C. We observe the highest ethanol conversions with acetaldehyde selectivity of about 80% and ethanol conversion of about 10% for catalytic samples involving a Cu/Ni molar ratio equal to 2.30. The highest conversion was obtained at 220C, but the catalyst deactivation upon a time was observed. The characterization of the catalyst after the use was done. The electron microscopy confirmed that the microstructure remained mesoporous and free of oxides. Oxide-free structure and nanometer-size particles of CuNi were also confirmed by X-ray powder diffraction analysis. The leading cause of catalyst deactivation is not oxidation but coke forming. The results were compared with a similar experiment on copper NPs.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/LUAUS23085" target="_blank" >LUAUS23085: Syntéza nových vysoce aktivních metalosilikátových katalyzátorů pro metatezi olefinů</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů