The silicate anion structure and thermal decomposition behavior of okenite were studied mainly using solid 29Si NMR. The silicate anion structure of okenite is very close to some parts of the sheet structure of gyrolite. Dehydration occurs at around 119 and 315 °C which are caused by the decomposition of the double-chain and sheet structure, and the sheet structure, respectively. Although, the dehydration is caused by the water in the interlayer of okenite, and the main silicate anion structure remains until around 350 °C. From 350 to 700 °C, the silicate anion structure decompose gradually as the temperature increases and many kinds of silicate anions are formed from the double-chain and the sheet structure of okenite. By the thermal treatment above 800 °C, wollastonite, pseudo-wollastonite and amorphous silica are formed and pseudo-wollastonite, cristobalite, quartz and silica glass are formed over 1200 °C.
|Number of pages||6|
|Journal||Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan|
|Publication status||Published - 1994|
ASJC Scopus subject areas
- Ceramics and Composites
- Condensed Matter Physics
- Materials Chemistry