Effects of host micas, interlayer cations and the addition of PVA on formation and porous properties of fluorine mica-iron(III) oxide composites

Syntheses of Fe2O3-pillared fluorine micas have been undertaken using Na-te trasilicic fluorine mica [NaMg2.5Si4O10F2], Na-taeniolite series mica [Na0. 5Mg2.5Li0.5Si4O10F2] and their Li+-exchanged forms as host crystals in the presence or absence of PVA as a template agent. The properties and structur es of the products depend on the species of host crystals and interlayer ca tions as well as on the addition of PVA. Fe2O3-pillared fluorine micas obta ined from the Li-exchanged form of the taeniolite series mica retained pill ared structure up to 600 degreesC and had pores with mean diameter around 3 .3 nm. On the other hand. the products ohtained from the Li-exchanged form of Na-tetrasilicic mica with using PVA had the "house-of-cards" structure c onsisting of delaminated Fe2O3-pillared mica flakes and Fe2O3 particles dep osited on the external surface of the micaflakes. They can be called "Fe2O3 pillared mica - Fe2O3 " composites which are featured by mesopore distribu tions in the range of 3.3 - 6.9 run, depending on the heating temperature. They gave sintered bodies above 500 degreesC and exhibited a maximum BET sp ecific surface area of 110 m(2)g(-1) at 600 degreesC.