EXTRACTION OF POTASSIUM FROM GLAUCONITIC SANDSTONE BY THE ROAST LEACHMETHOD

Laboratory studies have been conducted on the roast-leach method as a possible route of extraction of potassium from glauconitic sandstone. Roasting kinetics with calcium chloride has been investigated. The eff ect of roasting time, temperature, particle size and ratio of glauconi tic sandstone/calcium chloride on roasting of potassium have been inve stigated. After roasting potassium has been recovered in the from of p otassium chloride by leaching with distilled water. The dissolution ra te at different temperatures has also been studied. The roasting react ion has been found to follow the well defined Ginstling-Brounshtein di ffusion equation 1-2/3R-(1-R)2/3=Kt The diffusion through the product layer has been found to be the rate controlling step. The activation e nergy for roasting has been found to be 103.3 kJ/mole.