Apparatus for producing fine metal particles

摘要

An apparatus for producing a particulate metal or alloy having a diameter of less than 5 microns by the reaction of a molten metal or alloy with activated hydrogen. The apparatus has (1) a metal melting hearth for melting a starting metal or alloy placed thereon and supporting the molten metal or alloy, (2) a discharge electrode positioned above, and opposite to, the metal or alloy placed on the melting hearth, (3) a closed vessel for containing the melting hearth and the discharge electrode, and (4) a gas inlet port in the wall of the closed vessel for introducing hydrogen or a hydrogen-containing gas into the vessel. The apparatus includes a device for quickly moving fine particles of the metal or alloy generated from the molten metal or alloy away from the vicinity of the molten metal by means of a current of hydrogen or a hydrogen-containing gas constituted by a suction duct for sucking a gas in the vicinity of the molten metal or alloy and withdrawing it out of the vessel and which extends into the vessel through the vessel wall and opens in the vicinity of the molten metal or alloy on the melting hearth; or a device for sending hydrogen or a hydrogen-containing gas into the closed vessel so as to form a turning flow of hydrogen or the hydrogen-containing gas moving downwardly from above the molten metal on the melting hearth or upwardly from below the molten metal. The improved apparatus also includes a trap for collecting the fine metal particles connected to the suction duct, a gas outlet or a gas passage, and a gas cooler provided upstream of the trap. The apparatus of this invention makes possible the production of fine particles of a metal or alloy having a narrow particle size distribution with a high recovery ratio.