Naslov
Oxygen storage capacity versus catalytic activity of ceria–zirconia solid solutions in CO and HCl oxidation

Autori
Djerdj, Igor ; Sun, Yu ; Li, Chenwei ; Khalid, Omeir ; Cop, Pascal ; Sann, Joachim ; Weber, Tim ; Werner, Sebastian ; Turke, Kevin ; Guo, Yanglong ; Smarsly, Bernd ; Over, Herbert

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
21st Annual Conference YUCOMAT 2019 & 11th World Round Table Conference on Sintering WRTCS 2019 - Programme and Book of Abstracts / Uskoković, Dragan ; Radmilović, Velimir - Herceg Novi : Materials Research Society of Serbia, 2019, 125-125

ISBN
978-86-919111-4-0

Skup
21st Annual YUCOMAT Conference (YUCOMAT 2019) ; 11th World Round Table Conference on Sintering (WRTCS 2018)

Mjesto i datum
Herceg Novi, Crna Gora, 02.09.2019. - 06.09.2019

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
oxygen storage capacity ; ceria-zirconia solid solutions ; CO oxidation ; HCl oxidation

Sažetak
Oxygen storage in solid catalyst is very important for industrial oxidation reactions such as HCl oxidation reaction (Deacon process). Ceria nanoparticles act as promising catalysts for HCl oxidation reaction. Ceria possesses high OSC (oxygen storage capacity) which is a measure of the oxygen quantity that material can store and release. This makes ceria suitable for redox reactions which usually follow Mars-van Krevelen mechanism (surface oxygen atoms directly involved in reactions). CexZr1−xO2 solid solutions were prepared as a function of the composition x with constant specific surface area in order to explore the relationship between oxygen storage capacity (OSC) and activity of the oxidation reactions of CO and HCl. The as-prepared CexZr1−xO2 solid solutions were characterized by X-ray diffraction (XRD), Raman spectroscopy (Raman), and X-ray photoelectron spectroscopy (XPS). The complete (or total) oxygen storage capacity (“complete” OSC: OSCc) at 430 °C is shown to be linearly correlated to the CO oxidation activity at 430 °C as a function of the Ce concentration x, thus being compatible with the expected Mars–van-Krevelen mechanism. For the catalytic HCl oxidation reaction at 430 °C the activity is also shown to be linearly correlated to the OSCc with a maximum activity realized with Ce0.8Zr0.2O2. From the linear relationship of oxidation activity of HCl and OSCc (that in turn is linear to the activity of CO oxidation) we conclude that the HCl oxidation reaction over CexZr1−xO2 solid solutions proceeds via the Mars–Van-Krevelen mechanism with the reduction of CexZr1−xO2 being rate-determining.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

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