Abstract: Disclosed herein is a method for recovering an acid or a base during a metal extraction process. The method comprises contacting a feed stream comprising the acid or base and the metal with an ultrafiltration membrane to produce an ultrafiltration retentate and an ultrafiltration permeate, and contacting the ultrafiltration permeate with a nanofiltration membrane. The nanofiltration retentate produced comprises a majority of the metal from the feed stream, and the nanofiltration permeate produced comprises a majority of the acid or base from the feed stream. Also disclosed herein is a recovery apparatus for recovering an acid or a base during a metal extraction process.

Abstract: Disclosed herein is apparatus for recovering an acid or a base during a uranium extraction process. The apparatus contacts contacting a feed stream comprising the acid or base and the uranium with an ultrafiltration membrane to produce an ultrafiltration retentate and an ultrafiltration permeate, and contacting the ultrafiltration permeate with a nanofiltration membrane. The nanofiltration retentate produced comprises a majority of the uranium from the feed stream, and the nanofiltration permeate produced comprises a majority of the acid or base from the feed stream.