Potassium Release from Muscovite as Influenced by Particle Size

Abstract

Abstract-Completeness of exchange of K from muscovite by Ba 2+ ions decreased with particle size below 20/~. Accompanying K exchange at 120~ using a repeated batch technique, was a marked loss of Si and the formation of boehmite in the finer fractions. Several possible explanations for the unexpected high K retention of fine mica fractions are discussed.

Morphological Effects on Illite as A Result of Potassium Depletion

“…Brown and Rich (1968) and Reichenbach and Rich (1969) show micrographs of potassium depleted muscovite in which views normal to (001) planes reveal the preferential development of layers with varying potassium release. The latter authors suggest the layer separation may represent growth step planes in which ordering is less than in other layers.…”

“…Reichenbach and Rich, 1969). A first-order spacing of 12-1-12.3 seems typical for air-dried muscovite after maximum potassium withdrawal, but for illites the variation in spacings extends to 12.7 A.…”

“…Lodding, 1970) should also be taken into consideration. Reichenbach and Rich (1969) suggest that the high retention of potassium in the 0.08-0.2/x fraction of a prepared muscovite indicates a higher potassium selectivity than in the coarser 5-20/x fraction, and that potassium removal proceeds more by silicate dissolution than, as is the case with the larger particles, by ion exchange and layer bending. Scott (1968) has documented the relationship be-*Contribution No.…”

“…In this way it has become possible to determine potassium depletion rates for particles under a variety of conditions. Particular emphasis has been given to particle size (Reichenbach and Rich, 1969;Mortland and Lawton, 1961 ;Scott, 1968) and charge density (Ross and Kodama, 1970;Bassett, 1959) as factors most affecting potassium mobility in dioctahedral, aluminous, layer silicates although other authors point out that stage of weathering, type of interstratification, and structural change due to grinding (e.g. Lodding, 1970) should also be taken into consideration.…”

Experimental Transformation of 2M Sericite into a Rectorite-Type Mixed-Layer Mineral by Treatment with Various Salts

“…Loss of K changed micas into expanded layer silicates (Jackson and Sherman, 1953). Various chemical methods of extracting interlayer K from mica in the laboratory have been carried out with aqueous salt solutions (Barshad, 1948(Barshad, , 1954Caill~re et al, 1949;Mortland, 1958;Rausell-Colom et al, 1965;Reichenbach et al, 1969;Mamy, 1970). Interlayer K in muscovite has been extracted by treating the mineral with molten LiNO3 at 300~ (White, 1956(White, , 1958.…”