Extraction of uranium from wet-process phosphoric acid

A process for the extraction of uranium compounds from wet-process phosphoric acid (WPA), the process comprising:

• lowering iron content of the WPA to produce a lowered iron WPA;
• reducing valency of any remaining iron in the lowered iron WPA to produce a reduced iron valency WPA;
• and
• extracting uranium compounds from the reduced iron valency WPA;
• wherein reducing the valency of iron in the WPA comprises reducing ferric iron to ferrous iron by electro-reduction in an electrolytic cell.

A process for the extraction of uranium compounds from wet-process phosphoric acid (WPA), the process comprising:

• lowering the iron content of the WPA to produce a lowered iron WPA by increasing the redox potential of the WPA to approximately 500 mV as measured against an Ag/AgCl/saturated KCl reference electrode, adding ammonia, precipitating the iron as an iron ammonium phosphate, and separating the iron ammonium phosphate;
• separating from the lowered iron WPA a side stream having a greater concentration of the uranium compounds than the WPA by passing the lowered iron WPA through a filter membrane to produce a clean WPA permeate and a retentate as the side stream, the retentate comprising a greater concentration of the uranium compounds than the concentration of uranium in the permeate;
• reducing the valency of any remaining iron in the lowered iron WPA from ferric iron to ferrous iron using a process selected from one or more of the group consisting of:
• contacting the WPA with a reducing agent and electro-reduction in an electrolytic cell;
• and
• extracting uranium compounds from the reduced iron valency WPA.