Title :

Effect of Modification of Amorphous Silica with Ammonium Agents on the Physicochemical Properties and Hydrogenation Activity of Ir/SiO2 Catalysts

Author(s) :

Kot, Monika [Auteur]
Adam Mickiewicz University in Poznań [UAM]
Wojcieszak, Robert [Auteur]
Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181
Janiszewska, Ewa [Auteur]
Adam Mickiewicz University in Poznań [UAM]
Pietrowski, Mariusz [Auteur]
Faculty of Chemistry [Poznań]
Adam Mickiewicz University in Poznań [UAM]
Zieliński, Michał [Auteur]
Faculty of Chemistry [Poznań]
Adam Mickiewicz University in Poznań [UAM]

Journal title :

Materials

Abbreviated title :

Materials

Volume number :

14

Pages :

968

Publisher :

MDPI

Publication date :

2021-02-18

ISSN :

1996-1944

HAL domain(s) :

Chimie/Catalyse

English abstract : [en]

The modification of commercial silica with solutions of NH4F or NH4Cl salts, followed by thermal treatment, enabled generation of the acidic sites in SiO2 and changed its textural properties. The use of ammonium salts ...
Show more >The modification of commercial silica with solutions of NH4F or NH4Cl salts, followed by thermal treatment, enabled generation of the acidic sites in SiO2 and changed its textural properties. The use of ammonium salts solution also caused the generation of additional porosity. Using NH4F solution caused significant decrease in the specific surface area and the increase in the average pore diameter. The number and strength of resulting acid sites depend on the nature of anion in the applied ammonium salt and the concentration of salt solution. It has been found that the sample treated with NH4F presented higher total acidity (TPD–NH3) and the amount as well as the strength of acid sites increased with the concentration of the used modifier. As modified amorphous SiO2 materials used as a support for iridium (1 wt %, Ir(acac)3) nanoparticles permitted to obtain highly active catalysts for toluene hydrogenation under atmospheric pressure. The highest activity (expressed as the apparent rate and TOF) was obtained for iridium catalysts supported on silica modified by NH4F with the highest acidity. The modification of silica with NH4F favors the generation of centers able to adsorb toluene, which results in higher activity of this catalyst.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

CNRS
Centrale Lille
ENSCL
Univ. Artois
Université de Lille

Collections :

• Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181

Research team(s) :

Valorisation des alcanes et de la biomasse (VAALBIO)

Submission date :

2022-03-24T09:02:52Z
2023-01-18T10:24:51Z