Abstract: | Crystalline Silicic Acid with Distinct Intracrystalline Reactivity The crystalline silicic acid H2Si20O41 · xH2O is obtained from its alkali and alkaline-earth salts by cation exchange. The crystalline silicic acid and its salts form layered host lattiees which interealate many organic compounds. The increased intracrystalline reactivity and the reversible swelling in water distinguish H2Si20O41 · xH2O from the other silicic acids. Differences between samples of H2Si20O41 · xH2O are detected by intracrystalline reactions more clearly than by X-ray diffraction studies. Thermal dehydration at about 150°C gives Siliea-X, a partially dehydrated form (about SiO2 · 0,09 H2O). The aggregation of the plate-like crystals to spherical aggregates provides an interesting material for interface reactions. |