Suppressing on-stream deactivation of CuSiO2 catalysts in the dehydrogenation of bioethanol to acetaldehyde

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14740%2F24%3A00138738" target="_blank" >RIV/00216224:14740/24:00138738 - isvavai.cz</a>

Result on the web

<a href="https://pubs.rsc.org/en/content/articlelanding/2024/cy/d4cy00646a" target="_blank" >https://pubs.rsc.org/en/content/articlelanding/2024/cy/d4cy00646a</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/d4cy00646a" target="_blank" >10.1039/d4cy00646a</a>

Result language

angličtina

Original language name

Suppressing on-stream deactivation of CuSiO2 catalysts in the dehydrogenation of bioethanol to acetaldehyde

Original language description

Bioethanol upgrading to valuable platform molecules is a cornerstone of the emerging "integrated biorefinery" concept. Although active catalysts have already been developed for the non-oxidative dehydrogenation of ethanol to acetaldehyde, their rapid deactivation - through coking and sintering - is still an unsolved challenge. Herein, we study a 7.4 wt% Cu-SiO2 catalyst at 573 K for 8 or 24 hours under stable ethanol feed, we report in-depth characterization of the spent catalysts to univocally describe deactivation phenomena, and we propose reaction engineering procedures based on gas co-feed (O-2 or H-2) to decisively enhance the catalyst stability. Under the standard conditions, the pristine catalyst undergoes fast deactivation, as conversion drops from similar to 95% to similar to 25% in about 8 hours. While sintering is shown to occur during the reaction, we demonstrate that the main cause of deactivation is actually the accumulation of carbonaceous deposits. Even if such deactivation is shown to be reversible (regeneration by oxidative treatment), it is more attractive to prevent it from happening. Studying the effect of gas doping, we show that introducing a small fraction of oxygen (0.44 vol%) leads to a marked decrease of the extent of coking and stabilization of catalytic activity at a much higher conversion level (75% after 24 h). A slightly higher O2 concentration (1.77 vol%) leads to complete stabilization of the ethanol conversion (90% after 24 h), but concomitantly provokes a slight drop in acetaldehyde selectivity. With the findings of this study, with optimized reaction conditions and an ameliorated catalyst formulation, an outstanding acetaldehyde productivity (2.9 gaca gcat(-1) h(-1)) was maintained fully stable for 24 h.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10400 - Chemical sciences

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

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

Publication year

2024

Confidentiality

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

Name of the periodical

Catalysis Science and Technology

ISSN

2044-4753

e-ISSN

2044-4761

Volume of the periodical

14

Issue of the periodical within the volume

17

Country of publishing house

GB - UNITED KINGDOM

Number of pages

15

Pages from-to

4912-4926

UT code for WoS article

001276569200001

EID of the result in the Scopus database

2-s2.0-85199506964