الفهرس 
General concepts of clay structureOnly 14 pages are availabe for public view
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Abstract
The current work aimed at the kinetic study of the intercalation of " ~ "a+-montmorillonite by some organic compounds, such as metanil yellow dye, p-NH2-DPk and benzidine. This study is a novel one. For the first time it was possible to make a quantitave breakthrough of the intercalation process. To achieve the purpose of this study some fast reaction techniques were used. Stopped-flow technique monitored by both UV / Vis and electrical conductimetric detection units has been used. Some adsorption experiments have been carried out at diverse working conditions. It was found that the amount adsorbed of the organic compound increased in the following sequence: metanil yellow < p-NW2-DPA < benzidine. The intercalation of metanil yellow occurred only in the presence of strong acidic medium, whereas the intercalation of p-NH2-DPA and benzidine takes place in aqueous medium. The oxidation process of the organic compounds was studied with stoppedflow UV Nis technique. The reaction rate increased in this sequence: benzidine < p-NH2-DPA < metanil yellow. The activation energy increased in this order: metanil yellow < p-NH2-DPA < benzidine. The effect of clay concentration, ionic strength and pH on the oxidation rate has been investigated. Even more interesting is the determination of the fractional attainment of equilibrium (Qt / Q,) of the organic compounds. The thermodynamic equilibrium constant, Kc. is a function of Qt / Q,. The positive AH values followed the order: metanil yellow < p-NH2-DPA < benzidine. This means that’ with benzidine the intercalation process was the slowest one.