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Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Causes of deactivation of chromium-containing Y type zeolites in hydration of olefins
Summary A consequence of hydration of C2-C4 olefins to corresponding alcohols on Cr and Ce-containing Y type zeolites is a combination of reversible and irreversible deactivation of the catalyst due to considerable coke formation. Irreversible deactivation of the Y type zeolites is caused by oxidation of Cr(III)→Cr(VI) and Ce(III)→Ce(IV) during oxidative recovery of the catalyst, followed by leaching of chromium in the form of soluble Ca, La and Al chromates. Chromium introduced into high-silica zeolite is demonstrated not to occupy ion-exchange places in the high-silica zeolite lattice and when heated in air, it does not change the valence state but forms a Cr2O3 phase. This explains the stability of high-silica zeolites containing chromium.
Causes of deactivation of chromium-containing Y type zeolites in hydration of olefins
Summary A consequence of hydration of C2-C4 olefins to corresponding alcohols on Cr and Ce-containing Y type zeolites is a combination of reversible and irreversible deactivation of the catalyst due to considerable coke formation. Irreversible deactivation of the Y type zeolites is caused by oxidation of Cr(III)→Cr(VI) and Ce(III)→Ce(IV) during oxidative recovery of the catalyst, followed by leaching of chromium in the form of soluble Ca, La and Al chromates. Chromium introduced into high-silica zeolite is demonstrated not to occupy ion-exchange places in the high-silica zeolite lattice and when heated in air, it does not change the valence state but forms a Cr2O3 phase. This explains the stability of high-silica zeolites containing chromium.
Causes of deactivation of chromium-containing Y type zeolites in hydration of olefins
Tolkacheva, L.N. (Autor:in) / Novikova, L.A. (Autor:in) / Mikheikin, I.D. (Autor:in) / Kustov, L.M. (Autor:in) / Minachev, Kh.M. (Autor:in)
05.11.1984
5 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
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