Effect of the Chemical and Phase Composition of Nanocrystalline Gadolinium Complex Oxides on the Propane Cracking Process

Abstract: Effect of the chemical composition and crystal structure type of gadolinium complex oxides on their catalytic activity is studied. It is shown that nanocrystalline powders Gd2Ti2O7, Gd2Zr2O7, and Gd2Hf2O7 form highly symmetrical face-centered сubic crystal structures having localized (in Gd2Ti2O7) and delocalized (in Gd2Zr2O7 and Gd2Hf2O7) oxygen vacancies. At the same time, low-symmetrical crystal structures are formed in Gd2(WO4)3 (the monoclinic structure) and Gd2(МоO4)3 (a mixture of monoclinic and rhombic structures). Catalytic runs show that formation of the cubic structure contributes to an increase in the degree of conversion of propane and causes a shift in cracking temperatures to lower values. Formation of this type of nanocrystalline oxides facilitates the dehydrogenation reaction with propylene selectivity up to 80% at temperatures up to 700 К. Formation of the mixture of monoclinic and rhombic structures in Gd2(МоO4)3 leads to a shift in the degree of conversion to the catalytic temperature range of 700–900 К, in which the dehydrogenation reaction predominates (80%). In the case of the monoclinic structure of Gd2(WO4)3 in the same cracking temperature ranges the process of degradation occurs in parallel; this decreases propylene selectivity to 50% and promotes an increase in the yield of ethylene to 30%. © 2020, Pleiades Publishing, Ltd.

Авторы
Markova E.B. 1 , Popov V.V. 2 , Kovtun S.O. 1 , Menushenkov A.P. 2 , Yastrebtsev A.A. 2 , Molokova A.Y.2 , Tereshina T.A. 1 , Shchetinin I.V.3 , Ponkratov K.V.4
Журнал
Номер выпуска
5
Язык
Английский
Страницы
601-608
Статус
Опубликовано
Том
60
Год
2020
Организации
  • 1 Peoples’ Friendship University of Russia, Moscow, 117198, Russian Federation
  • 2 National Research Nuclear University (MIFI), Moscow, 115409, Russian Federation
  • 3 National University of Science and Technology (MISIS), Moscow, 119049, Russian Federation
  • 4 OOO Renishou, Moscow, 115477, Russian Federation
Ключевые слова
ethylene; nanocrystalline gadolinium complex oxides; propane dehydrogenation; propane destruction; propylene
Дата создания
02.11.2020
Дата изменения
02.11.2020
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/64800/