(C₃H₆O₂)₂, (Si₆O₁₂)₂, a new silica sodalite synthesized, using 1,3-dioxolane as template

verfasst von

Gianpietro van de Goor, Peter Behrens, Jürgen Felsche

Abstract

A clathrasil with SOD structure has been obtained using 1,3-dioxolane as a template. The synthesis was achieved under hydrothermal conditions at temperatures between 423 and 433 K in the SiO₂Na₂OC₃H₆O₂H₂O system. The choice of the template was guided by stereochemical comparisons with the templates known for silica sodalite synthesis, ethylene glycol and 1,3,5-trioxane. The powder X-ray diffraction (XRD) measurement of dioxolane silica sodalite (C₃H₆O₂)₂(Si₆O₁₂)₂ showed the typical pattern of silica sodalites with sharp, discrete reflections indicating high crystallinity. Indexing and refinement of the diffraction pattern gave a body-centered cubic unit cell with a lattice constant a₀=8.868(1) Å at room temperature, which is significantly larger than previously found in other silica sodalites. The value of a₀ agrees with the SiOSi bonding angle derived from the position of the ²⁹Si NMR signal. Infrared (IR) and ¹H,¹³C nuclear magnetic resonance (NMR) spectroscopic data are in agreement with dioxolane molecules occluded in a porous matrix. The weight loss during thermal analysis in an oxygen atmosphere shows that within the limits of the method each sodalite cage is occupied by one 1,3-dioxolane molecule. Differential scanning calorimetry (DSC) between 120 and 470 K reveals a reversible, temperature-induced phase transition at 271 K.

Externe Organisation(en)

Universität Konstanz

Typ

Artikel

Journal

Microporous Materials

Band

2

Seiten

493-500

Anzahl der Seiten

8

ISSN

0927-6513

Publikationsdatum

07.1994

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Chemie (insg.), Werkstoffwissenschaften (insg.), Ingenieurwesen (insg.)

Elektronische Version(en)

https://doi.org/10.1016/0927-6513(94)E0064-2 (Zugang: Geschlossen)