Reactions of Molten Salts with Layer-Lattice Silicates1

Joe L. White
Agronomy Department, Purdue University, Lafayette, Indiana
1 Journal Paper no. 931, Purdue University Agricultural Experiment Station, Lafayette, Indiana.

Abstract: A preliminary x-ray diffraction study of the effect of treatment of typical layer-lattice silicates with molten lithium, sodium, and potassium nitrates has been made. Treatment of Wyoming bentonite (Upton, Wyoming) with molten lithium nitrate produced random interstratification of spacings of 9.6 and 17.8 A when specimens were glycerol-solvated, with approximately 20 percent expanded layers. Treatment with sodium nitrate at 320° C produced a very high degree of preferred orientation in film specimens dried from water, whereas treatment with molten potassium nitrate produced a more random orientation in the specimen. The bentonite treated with molten sodium nitrate expanded completely to 17.8 A with glycerol; treatment with potassium nitrate resulted in a small amount of random interstratification, the proportion of expanded layers being about 80 percent.

Treatment of the <5µ fraction of Delamica (muscovite) with molten lithium nitrate removed a large portion of the potassium from the mica, and lithium was fixed in a not readily exchangeable manner. When barium-saturated and glycerol-solvated, the treated material gave an 001 spacing of 17.8 A, the basal spacing for glycerol-montmorillonoids. The amount of potassium removed from the muscovite varied with the muscovite/lithium-nitrate ratio and length of treatment.

Clays and Clay Minerals; 1955 v. 4; no. 1; p. 133-146; DOI: 10.1346/CCMN.1955.0040118
© 1955, The Clay Minerals Society
Clay Minerals Society (www.clays.org)