Device and method for extracting a constituent from a chemical mixture

• Main Authors: Putvinski, Sergei, Volosov, Vadim
• Format: Patent
• Language: English
• Published: 28.10.2003

The present invention pertains generally to the extraction of a constituent from a chemical mixture. More particularly, the present invention pertains to plasma devices and methods for ionizing the constituents of a chemical mixture and separating the resulting ions according to their relative mass to charge ratio. The present invention is particularly, but not exclusively, useful for generating an ion beam containing one or more selected ions from a chemical mixture such as a metallic alloy. A device for separating a chemical mixture into its constituents includes a central cathode that is aligned axially within a cylindrical plasma chamber. An anode, made of the chemical mixture requiring separation is positioned near the cylindrical wall of the plasma chamber. A working gas is introduced into the chamber to sputter the chemical mixture into the plasma chamber where it is dissociated and ionized. To reduce the unwanted loss of the central cathode due to sputtering by the working gas, the central cathode is formed with a plurality of radial projections that extend outwardly from the axis of the cylindrical plasma chamber. These radial projections act to capture sputtered cathode material before it is lost to the plasma. Once the chemical mixture has been ionized in the plasma chamber, the ions are separated, according to their respective mass to charge ratio, using crossed electric and magnetic fields.