Patent ID: 11920250
Assignee: THE TEXAS A&M UNIVERSITY SYSTEM
Field: Surface technology, coating (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A process for separating a rare-earth metal of interest from a natural salt-containing water, comprising:
applying an electric field across an electrodialysis metathesis system comprising at least one electrodialysis quad of a feed compartment to receive a salt-containing water, a substitution solution compartment containing a substitution salt solution, a first concentrated compartment, and a second concentrated compartment, each of said compartments in fluid communication via alternating cation- and anion-exchange membranes;
exchanging cations and anions in the natural salt-containing water with cations and anions in the substitution salt solution via a metathesis reaction thereby producing in the first concentrated compartment a first concentrate of a salt composed of cations from the substitution salt solution and anions from the natural salt-containing water and producing in the second concentrated compartment a second concentrate of a salt composed of rare earth metal cations and other cations from the natural salt-containing water and anions from the substitute salt solution;
removing the first concentrate and the second concentrate from the electrodialysis metathesis system and combining the same to produce a combined concentrate; and
adjusting pH of the combined concentrate to precipitate the rare earth metal of interest.