Embodiments of a method and a system for recovering a metal, such as
uranium, from a metal-containing material are disclosed. The
metal-containing material is exposed to an extractant containing a liquid
or supercritical-fluid solvent and an acid-base complex including an
oxidizing agent and a complexing agent. Batches of the metal-containing
material are moved through a series of stations while the extractant is
moved through the stations in the opposite direction. After the
extraction step, the metal is separated from the solvent, the complexing
agent and/or other metals by exposing the extract to a stripping agent in
a countercurrent stripping column. The complexing agent and the solvent
exit the column and are separated from each other by reducing the
pressure. The recovered complexing agent is recharged with fresh
oxidizing agent and recombined with fresh or recovered solvent to form a
recovered extractant, which is distributed through the extraction
stations.