Alumina Extraction from a Pennsylvania Diaspore Clay by an Ammonium Sulfate Process

Abstract

A method is proposed for the extraction of alumina from the minerals diaspore, kaolinite and boehmite, the major alumina usinerais in Pennsylvania diaspore clay. The conditions required for optimum alumina extraction and minimum ammonium sulfate loss as determined for the alumina minerals are applied to a naturally occurring diaspore clay. The proposed flowsheet thus obtained is examined in its parts and such variables as particle size, ammonium sulfate to alumina mole ratio, roasting temperature, roasting time, heating rate, leaching cohditions, and purification methods are discussed.