Abstract: A fluidized bed electrowinning system and method includes a fluidized bed reaction vessel in which a fluidized bed of conductive particles serves as the cathode for the electrowinning reaction, the anodes being in the form of hollow tubes of electrochemically active material inserted into the fluidized bed and separated therefrom by a membrane. The catholyte and anolyte are separately supplied from an electrolyte supply tank, the catholyte being pumped through the conductive particles to form the fluidized bed and the anolyte being supplied to individual anodes, and are commingled at the top of the reaction vessel before return to the supply tank. Removal of particles from the tank occurs through a part in the side of the tank, the removed particles normally being recycled through a selector valve back into the tank to maintain continuous operation.

Abstract: Gold, copper, silver, palladium or aluminum and their alloys, but preferably gold or gold alloy, which may be in the form of a wire, has deposited thereon or contained within the wire, a material such as metals or metal alloys which diffuse into the gold or into the other listed metals. With the passage of time and exposure to temperature the deposited metal or metal alloy continues to diffuse into the gold forming intermetallics with the gold and thereby causing the resistivity of the gold to increase and causing the gold to become progressively more brittle until such time as the gold wire ruptures at a stress point. At a given temperature, the elapsed time until rupture takes place depends upon the metal or metal alloys deposited on or contained within the gold. Lead, indium, gallium, tin, bismuth and aluminum and the alloys of these metals diffuse into and form intermetallics with the gold.

Abstract: Flotation apparatus and methods for separating particles from particulate suspensions such as coal and mineral ore slurries, wherein fluid discharge is removed annularly from a flotation vessel. Preferably, the flotation apparatus includes a vertically oriented, cylindrical flotation vessel having a tangential inlet at its upper end and an annular outlet at its lower end. The annular outlet allows for the smooth exit of fluid discharge from the flotation vessel so as to avoid disturbance of the fluid flow within the flotation vessel. The apparatus includes a froth pedestal positioned within the lower end of the vessel which forms the annular outlet with the wall of the vessel. The froth pedestal further serves to support a froth column formed within the flotation vessel and isolates the froth column from the fluid discharge so as to minimize mixing therebetween.