CESIUM-AND STRONTIUM-EXCHANGE PROPERTIES OF THERMALLY ALTERED Na-MONTMORILLONITE

概要

論文の詳細を見る
The Na-Cs and Na-Sr exchange properties of Na-montmorillonite heated at various temperatures under dry conditions have been studied at 25℃ and a constant normality of solution. The standard free energy changes were -2.6 kcal/eq for Na-Cs and -0.99 kcal/eq for Na-Sr in the air-dried montmorillonite. In the montmorillonite pre-heated at 100°-600℃, the Cs-selectivity increased in the smaller Cs-equivalent fraction in clay but such an increase did not appear in the Na-Sr exchange. In addition, complete exchange from Na-form to Cs-and Sr-forms was not achieved in the pre-heated materials because of fixation of interlayer Na. The proportions of fixed Na were less than 10% upon heating at<300℃ but increased to 25-30% for Na-Cs and 15-20℃ for Na-Sr by heating at 600℃. These values were nearly constant indifferent to normality of solution and exchange temperature.
日本粘土学会の論文