Combined in situ XPS and PTRMS Study of Ethylene Epoxidation Over Silver | Sciact - CRIS-система Института катализа

Combined in situ XPS and PTRMS Study of Ethylene Epoxidation Over Silver Научная публикация

Журнал

Journal of Catalysis
ISSN: 0021-9517 , E-ISSN: 1090-2694

Вых. Данные

Год: 2006, Том: 238, Номер: 2, Страницы: 260-269 Страниц : 10 DOI: 10.1016/j.jcat.2005.11.043

Ключевые слова

Catalyst, Epoxidation, Ethylene, In situ XPS, Oxygen, PTRMS, Silver

Авторы

Bukhtiyarov Valerii I. ¹ , Nizovskii Alexander I. ¹ , Bluhm Hendrik ² , Hävecker Michael ² , Kleimenov Evgueni ² , Knop-Gericke Axel ² , Schlögl Robert ²

Организации

1	Boreskov Institute of Catalysis, Lavrentieva ave. 5, Novosibirsk, 630090, Russia
2	Fritz-Haber-Institut der MPG, Faradayweg 4-6, Dahlem, Berlin, Germany

Ethylene epoxidation over silver was investigated by combined in situ X-ray photoelectron spectroscopy (XPS) and proton-transfer reaction mass spectrometry (PTRMS) at 300–520 K and 0.07–1 mbar. Ethylene oxide was present among the reaction products at T⩾420 K and p⩾0.3 mbar. The catalytically active surface contains two oxygen species – nucleophilic and electrophilic oxygen. The observed correlation between the abundance of electrophilic oxygen and the yield of ethylene oxide expressed as C2H4O partial pressure indicates that namely this oxygen species oxidizes ethylene to ethylene oxide. Opposite trend is observed for nucleophilic oxygen: the higher is the abundance of this species, the lower is the yield of ethylene oxide. This result is in line with the known fact that because of its oxidic nature, nucleophilic oxygen is active in total oxidation of ethylene to CO2 and H2O. The low activity of silver at T<420 K is caused by the presence of carbonates and carbonaceous residues at the silver surface that reduce the available silver surface area for the catalytic reaction. Reduction of the surface area available for the formation of active species due to accumulation of the embedded oxygen species also explains the decreased rate of ethylene oxide formation with time observed for T⩾470 K.

Bukhtiyarov V.I. , Nizovskii A.I. , Bluhm H. , Hävecker M. , Kleimenov E. , Knop-Gericke A. , Schlögl R.
Combined in situ XPS and PTRMS Study of Ethylene Epoxidation Over Silver

Journal of Catalysis. 2006. V.238. N2. P.260-269. DOI: 10.1016/j.jcat.2005.11.043 WOS Scopus РИНЦ CAPlusCA OpenAlex

Полный текст от издателя

Поступила в редакцию:	31 мар. 2005 г.
Принята к публикации:	21 нояб. 2005 г.
Опубликована online:	18 янв. 2006 г.
Опубликована в печати:	10 мар. 2006 г.

Web of science:	WOS:000235625100003
Scopus:	2-s2.0-32344440966
РИНЦ:	13522863
Chemical Abstracts:	2006:128611
Chemical Abstracts (print):	144:330972
OpenAlex:	W2169073867

БД	Цитирований
Web of science	120
Scopus	123
РИНЦ	117
OpenAlex	133