Surface and intercalate chemistry of layered silicates. Part I. General introduction and the uptake of benzidine and related organic molecules by montmorillonite

Abstract

Various types of novel reactions (relevant in bio-organic, inorganic, and prebiological contexts) which can be effected within spaces between the layers, or at the surfaces, of sheet-silicate minerals are summarized. The colour reactions displayed by nine selected nitrogen-containing small aromatic molecules when they complex with montmorillonite are also briefly reviewed, together with the results of a quantitative adsorptive study of benzidine on this particular mineral. Concurrent measurement of Na⁺-ion release from, and uptake of benzidine by, the mineral, and X-ray measurements of interlayer spacings, clearly reveal pre- and post-intercalation stages of the formation of the complex.