Patent ID: 7879219

Claim:
A method for processing a solid material (M 1 X) comprising a solid solution of a non-metal species (X) in a metal or semi-metal (M 1 ) or a compound containing the non-metal species (X) and the metal or semi-metal (M 1 ), to remove the non-metal species (X) from the solid material (M 1 X) and thereby produce a product having a desired reduced content of the non-metal species, which comprises the steps of: a) contacting a melt comprising a fused salt (M 2 Y) with the solid material and with an anode and applying a cathodic potential to the solid material so that a first portion of the non-metal species is removed from the solid material; discontinuing the process of step a) after the first portion of the non-metal species has been removed from the solid material, the removal of the first portion of the non-metal species being insufficient to produce the product having the desired reduced content of the non-metal species; b) electronically connecting a reactive metal or semi-metal (M 3 ) to the solid material while contacting the melt (M 2 Y) with the solid material and the reactive metal so that the reactive metal reacts with a second, further, portion of the non-metal species to form a reaction product (M 3 X) which is more stable than a compound between the non-metal species (X) and the metal or semi-metal (M 1 ); and discontinuing the process of step b) after the second, further portion of the non-metal species has been removed from the solid material, removal of both the first portion and the second portion of the non-metal species being sufficient to produce the product having the desired reduced content of the non-metal species.