US 7,572,315 B2 · Process for the synthesis, separation and purification of powder materials

Abstract

The invention concerns a process for the spheroidisation, densification and purification of powders through the combined action of plasma processing, and ultra-sound treatment of the plasma-processed powder. The ultra-sound treatment allows for the separation of the nanosized condensed powder, referred to as ‘soot’, from the plasma melted and partially vaporized powder. The process can also be used for the synthesis of nanopowders through the partial vaporization of the feed material, followed by the rapid condensation of the formed vapour cloud giving rise to the formation of a fine aerosol of nanopowder. In the latter case, the ultra-sound treatment step serves for the separation of the formed nanopowder form the partially vaporized feed material.

Claims27

Dependent claims

A process for the purification of a material comprising:

providing powder particles of the material including impurities;
plasma heating and melting of said powder particles of the material and release of said impurities in vapour phase through a plasma stream, yielding molten particle droplets of the material mixed in said plasma stream and vaporized impurities;
cooling of said molten particle droplets of the material mixed in said plasma stream with said vaporized impurities, yielding a mixture of purified powder particles of the material and soot;
exposing said mixture of purified powder particles of the material and soot material to ultrasound vibrations in a sonification medium, yielding separated purified powder particles of the material and soot in said sonification medium;
and
recovering said purified powder particles of the material from said sonification medium and said soot.

3 more elements

Dependencies are inferred from the claim text.

Process for the synthesis, separation and purification of powder materials

Life of this patent

Process for the synthesis, separation and purification of powder materials

Life of this patent

Abstract

Claims27