Reconstructed Mg-Al hydrotalcites prepared by using different rehydration and drying time: Physico-chemical properties and catalytic performance in aldol condensation

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22320%2F17%3A43913297" target="_blank" >RIV/60461373:22320/17:43913297 - isvavai.cz</a>

Alternative codes found

RIV/62243136:_____/17:N0000003 RIV/60461373:22350/17:43913297

Result on the web

<a href="http://www.sciencedirect.com.ezproxy.vscht.cz/science/article/pii/S0926860X17300856?via%3Dihub" target="_blank" >http://www.sciencedirect.com.ezproxy.vscht.cz/science/article/pii/S0926860X17300856?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.apcata.2017.02.020" target="_blank" >10.1016/j.apcata.2017.02.020</a>

Result language

angličtina

Original language name

Reconstructed Mg-Al hydrotalcites prepared by using different rehydration and drying time: Physico-chemical properties and catalytic performance in aldol condensation

Original language description

Aldol condensation in presence of reconstructed hydrotalcites as basic catalysts is well documented and attracts an increased attention because it allows producing complex molecules starting from relatively simpler ones. Nevertheless, more studies are necessary for the better understanding of preparation factors that affect the physico-chemical properties of these materials and their catalytic performance. This work considers the effect of the duration of the liquid-phase rehydration of Mg-Al mixed oxide as well as the drying duration of prepared samples on their physico-chemical properties and performance in aldol condensation of furfural and acetone. The properties of all materials were investigated by XRD, TGA, TGA-MS, SEM and DRIFT. Experiments on aldol condensation of furfural and acetone were performed by using a stirred batch reactor at T = 25 °C with Ac:F = 5 molar ratio. The characterization of the prepared materials showed that the recovery of HTC structure occurred within a few seconds of the contact between Mg-Al mixed oxide with liquid water. The content of functional species in all reconstituted HTCs was nearly constant and independent on preparation conditions while the amount of physisorbed water in the prepared samples decreased with increasing drying time. The calcination of as-prepared HTC followed by the subsequent rehydration of Mg-Al mixed oxide resulted in the replacement of &gt;90% carbonate groups on hydroxyls which are Br?nsted basic sites. Consequently, the activity of the reconstructed HTCs in aldol condensation of furfural and acetone was significantly higher compared to Mg-Al mixed oxide. The catalytic performance of rehydrated materials was almost independent on rehydration time while furfural conversion decreased if carrying out the reaction in an aqueous medium with increased water content. On the other hand, properly dried reconstructed HTC with the absence of physisorbed water also exhibited a very low activity in the reaction.

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

10403 - Physical chemistry

Project

<a href="/en/project/GA15-21817S" target="_blank" >GA15-21817S: Analysis of the structure/activity relationship of Mg/Al, Ca/Al and Zn/Al mixed oxides in aldol condensation and transesterification reactions</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

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

Name of the periodical

APPLIED CATALYSIS A-GENERAL

ISSN

0926-860X

e-ISSN

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Volume of the periodical

536

Issue of the periodical within the volume

APR 25 2017

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

12

Pages from-to

85-96

UT code for WoS article

000398647200010

EID of the result in the Scopus database

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