“Fluoride Aided Leaching of Glauconitic Sandstone for a Fluid Fertilizer”, Minerals Engineering.

Quantitative extraction of potassium from glauconitic sandstone with dilute sulphuric acid, in the presence of fluoride ion has been rationalized on the basis of the synergistic effect exerted by both the cations and anions of the added fluoride salts. It has been shown that the reaction kinetics follow the well defined Crank-Ginstling Brounshtein diffusion equation throughout the process