Synthesis of 1:1 and 2:1 Iron Phyllosilicates and Characterization of their Iron State by Mössbauer Spectroscopy

Tadashi Mizutani1, Yoshiaki Fukushima, Akane Okada, Osami Kamigaito and Takayuki Kobayashi2
Toyota Central Research and Development Labs, Inc., Nagakute, Aichi-gun 480-11, Japan
2 Department of Physics, Shiga University of Medical Science Ohtsu-shi, Shiga 520-21, Japan
1Present address: Department of Materials Science, Tottori University, Koyama-cho, Tottori 680, Japan.

Abstract: Iron phyllosilicates with 1:1 and 2:1 layer structures were prepared from silicic acid, ferrous sulfate and sodium hydroxide. Hydrothermal treatment at 100–200°C of a reaction mixture with an initial Fe/Si ratio of 1.5 gave the 2:1 iron phyllosilicate, whereas a Fe/Si ratio of 2.25 gave the 1:1 phyllosilicate. The 57Fe Mössbauer spectroscopy showed that 60% of the iron in the 1:1 phyllosilicate is ferrous, versus only 3% in the 2:1 phyllosilieate. The values of quadrupole coupling showed that the iron-oxygen tetrahedra and octahedra in the 2:1 phyllosilicate were more deformed than those in the 1:1 phyllosilicate.

Key Words: Iron • Mössbauer spectroscopy • Phyllosilicate • Synthesis

Clays and Clay Minerals; August 1991 v. 39; no. 4; p. 381-386; DOI: 10.1346/CCMN.1991.0390407
© 1991, The Clay Minerals Society
Clay Minerals Society (www.clays.org)