Improvement of the conventional preparation methods in Co/BEA zeolites: Characterization and ethane ammoxidation

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216275%3A25310%2F19%3A39914514" target="_blank" >RIV/00216275:25310/19:39914514 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S1293255819300779?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S1293255819300779?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.solidstatesciences.2019.04.008" target="_blank" >10.1016/j.solidstatesciences.2019.04.008</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Improvement of the conventional preparation methods in Co/BEA zeolites: Characterization and ethane ammoxidation

Popis výsledku v původním jazyce

Ethane ammoxidation into acetonitrile (AN) was successfully catalyzed by Co/BEA solids issued from improved preparation methods. The catalyst issued from the impregnation of [Co(NH3)(6)](2+) complex into BEA zeolite is very active in ethane ammoxidation (48% of ethane conversion and 90% of selectivity towards AN at 450 degrees C). Over this solid, the combustion of hydrocarbon molecules into CO2 was inhibited since the inefficient oxidic species occupied hidden sites inside the zeolite host as demonstrated by the CO-TPR experiments. However, the exchange of [Co(OH2)(6)](2+) complex, accompanying the conventional impregnation and solid-state ion exchange, favoured the formation of Co3O4 oxide species, which restricted the ethane conversion into AN during ammoxidation. Nevertheless, the exchange of aqua complex in ammonia stream inhibited the formation of oxidic species and led to efficient ammoxidation catalysts. Meanwhile, ammonia favoured the formation of Co4N (detected by XRD, TPR and TPD) to the detriment of bare Co2+ ions. In this context, very low amounts (similar to 0.05 mmol g(-1)) of bare Co2+ ions, sited in the beta-sites, are sufficient to catalyze ammoxidation at 450 degrees C. However, beside their amount, the stability of these ions is a crucial parameter to be considered and studied by FTIR upon CO adsorption at -196 degrees C.

Název v anglickém jazyce

Improvement of the conventional preparation methods in Co/BEA zeolites: Characterization and ethane ammoxidation

Popis výsledku anglicky

Ethane ammoxidation into acetonitrile (AN) was successfully catalyzed by Co/BEA solids issued from improved preparation methods. The catalyst issued from the impregnation of [Co(NH3)(6)](2+) complex into BEA zeolite is very active in ethane ammoxidation (48% of ethane conversion and 90% of selectivity towards AN at 450 degrees C). Over this solid, the combustion of hydrocarbon molecules into CO2 was inhibited since the inefficient oxidic species occupied hidden sites inside the zeolite host as demonstrated by the CO-TPR experiments. However, the exchange of [Co(OH2)(6)](2+) complex, accompanying the conventional impregnation and solid-state ion exchange, favoured the formation of Co3O4 oxide species, which restricted the ethane conversion into AN during ammoxidation. Nevertheless, the exchange of aqua complex in ammonia stream inhibited the formation of oxidic species and led to efficient ammoxidation catalysts. Meanwhile, ammonia favoured the formation of Co4N (detected by XRD, TPR and TPD) to the detriment of bare Co2+ ions. In this context, very low amounts (similar to 0.05 mmol g(-1)) of bare Co2+ ions, sited in the beta-sites, are sufficient to catalyze ammoxidation at 450 degrees C. However, beside their amount, the stability of these ions is a crucial parameter to be considered and studied by FTIR upon CO adsorption at -196 degrees C.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

<a href="/cs/project/GBP106%2F12%2FG015" target="_blank" >GBP106/12/G015: Vývoj nových nanoporézních adsorbentů a katalyzátorů</a><br>

Návaznosti

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

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název periodika

Solid State Sciences

ISSN

1293-2558

e-ISSN

—

Svazek periodika

93

Číslo periodika v rámci svazku

July

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

11

Strana od-do

13-23

Kód UT WoS článku

000471692000003

EID výsledku v databázi Scopus

2-s2.0-85065501823