Skip to main content

Login for students

Login for employees

Publication detail

Controlled silica core removal from SiO2@MgAl core-shell system as a tool to prepare well-oriented and highly active catalysts
Authors: Kondratowicz Tomasz Stanisław | Šlang Stanislav | Dubnová Lada | Kikhtyanin Oleg | Bělina Petr | Čapek Libor
Year: 2022
Type of publication: článek v odborném periodiku
Name of source: Applied Clay Science
Publisher name: Elsevier Science BV
Place: Amsterdam
Page from-to: "106365-1"-"106365-12"
Titles:
Language Name Abstract Keywords
cze kontrolované odstranění jader siliky z SiO2@MgAl "core-shell" systému jako nástroj pro přípravu dobře orientovaných a vysoce aktivních katalyzátorů Nová metoda kontrolovaného odstranění jader SiO2 z SiO2@MgAl-LDH je představena. Vzniklé prázdné sféry si zachovávají svůj původní tvar a nekolapsují. Připravené materiály jsou testovány jako katalyzátory v aldolové kondenzaci furfuralu. Závislost koverze na molárním poměru Si/(Si+Mg+Al) je diskutována. core-shell struktura; vrstevnaté double hydroxidy; MgAl katalyzátory; aldolová kondenzace
eng Controlled silica core removal from SiO2@MgAl core-shell system as a tool to prepare well-oriented and highly active catalysts This manuscript presents the preparation of well-oriented @MgAl-layered double hydroxides (LDHs). It extends the reported preparation of SiO2@MgAl-LDH core-shell material (Si/(Si + Mg + Al) molar ratio = 0.54, Mg/Al = 2). There is introduced a new method for the gradual and controlled removal of the SiO2 core from SiO2@MgAl-LDH on treatment with a NaOH solution (1 M) for 1, 2, 4, and 6 h Si/(Si + Mg + Al) molar ratio from 0.06 to 0.52, Mg/Al = 2). Subsequent SiO2 leaching led to empty spheres with properties of the crystalline MgAl-LDH phase preserved. It is proved that @MgAl-LDH spheres formed do not collapse and hence, preserve their orig-inal spherical shape and structural properties. The potential of @MgAl-mixed oxides (MOs) obtained by thermal treatment of @MgAl-LDHs in catalysis is also demonstrated. When this material was used for the aldol condensation reaction of furfural with acetone, the best furfural conversion was obtained for @MgAl-MO with a Si/(Si + Mg + Al) molar ratio of 0.11. core-shell structures; layered double hydroxides; MgAl catalysts; Aldol condensation; base catalysis