Method of indirect chemical reduction of metals in waste

A method for the indirect chemical reduction of at least two components of a waste, comprising the steps of:

• a) directing the waste into a molten metal bath, the molten metal bath including a first reducing agent which, under the operating conditions of the molten metal bath, chemically reduces a metal of a first component of the waste to form a dissolved metal-containing intermediate;
• and
• b) exposing the metal of the intermediate to a second reducing agent in the molten metal bath, the second reducing agent, under the operating conditions of the molten metal bath, chemically reducing the intermediate at a rate, relative to the rate at which the first component of the waste is directed into the molten metal bath, which is sufficient to cause essentially all intermediate formed to dissolve in the molten metal bath for subsequent reduction of the metal component of the intermediate, thereby indirectly chemically reducing the first component of the waste;
• and thereafter
• c) directing a sacrificial metal into the molten metal bath after the second reducing agent has reduced the intermediate, the sacrificial metal being substantially soluble in the molten metal bath and having a lower free energy of oxidation than the second reducing agent, whereby the sacrificial metal reacts with a metal of a second component of the waste, the second component being substantially inert to the first and second reducing agents at the temperature of the molten metal bath, thereby chemically reducing the metal of the second component of the waste.

A method for chemically remediating a metal component of a metal-containing waste, comprising the steps of:

• a) directing the waste into a molten metal bath which includes a first reducing agent that, under the operating conditions of the molten metal bath, chemically reduces said component containing the metal contaminant of the metal-containing waste to form a metal-containing intermediate and a reduced metal component of the waste;
• b) exposing the metal of the metal-containing intermediate to a second reducing agent in the molten metal bath which, under the operating conditions of the bath, reduces said metal at a rate, relative to the rate at which the component of the waste is directed into the molten metal bath, which is sufficient to cause essentially all metal-containing intermediate formed to dissolve in the molten metal bath;
• and thereafter
• c) reclaiming the reduced metal component of the waste from the molten metal bath.