INTERCALATION AND EXCHANGE-REACTIONS OF CLAY-MINERALS AND NON-CLAY LAYER COMPOUNDS

Presently, a large variety of layered materials are synthesized that are able to intercalate neutral guest molecules or to exchange inorganic and organic ions for interlayer ions. Several of these materials are also found as minerals. The intracrystalline reactivity of a few selected compounds will be described and compared to clay minerals: intercalation into crystalline silicic acids; reactions of phosphates, arsenates, and sulfates; reactions of titanates, niobates, and molybdates with long chain alkylammonium ions, and anion exchange properties of double hydroxides. A general conclusion is that the non-clay minerals in many ways behave like clay minerals, but there is no doubt that the reactivity of clay minerals and the variety of their reactions cannot be exceeded by any other material.