Abstract: A process for the in-flight surface treatment of powders using a Dielectric Barrier Discharge Torch operating at atmospheric pressures or soft vacuum conditions is described herein. The process comprising feeding a powder material into the Dielectric Barrier Discharge Torch yielding powder particles exhibiting a reduced powder agglomeration feature; in-flight modifying the surface properties of the particles; and collecting coated powder particles. An apparatus for surface treating micro- and nanoparticles comprising a Dielectric Barrier Discharge Torch operating at atmospheric pressure or soft vacuum conditions is also described herein.

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.

Abstract: A process for the in-flight surface treatment of powders using a Dielectric Barrier Discharge Torch operating at atmospheric pressures or soft vacuum conditions is described herein. The process comprising feeding a powder material into the Dielectric Barrier Discharge Torch yielding powder particles exhibiting a reduced powder agglomeration feature; in-flight modifying the surface properties of the particles; and collecting coated powder particles. An apparatus for surface treating micro- and nanoparticles comprising a Dielectric Barrier Discharge Torch operating at atmospheric pressure or soft vacuum conditions is also described herein.

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.

Abstract: A process and apparatus for the synthesis of metal oxide nanopowder from a metal compound vapour is presented. In particular a process and apparatus for the synthesis of TiO2 nanopowder from TiCl4 is disclosed. The metal compound vapour is reacted with an oxidizing gas in electrically induced RF frequency plasma thus forming a metal oxide vapour. The metal oxide vapour is rapidly cooled using a highly turbulent gas quench zone which quickly halts the particle growth process, yielding a substantial reduction in the size of metal oxide particles formed compared with known processes. The metal compound vapour can also react with a doping agent to create a doped metal oxide nanopowder. Additionally, a process and apparatus for the inline synthesis of a coated metal oxide is disclosed wherein the metal oxide particles are coated with a surface agent after being cooled in a highly turbulent gas quench zone.