Making mineral salts from various sources
Hydrometallurgical systems, methods, and compositions are described in which organic amine-based lixiviants are utilized in the selective recovery of alkaline earth elements. The lixiviant can be regenerated and recycled for use in subsequent iterations of the process. Suitable lixiviant species include zwitterions, including zwitterion pairs that act as counterions to one another.
1. A mixture utilized in extraction of a metal hydroxide forming species comprising:
a lixiviant solution comprising a zwitterion species complex comprising a first member of a pair of zwitterions and a second member of a pair of zwitterions;
a raw material comprising the metal hydroxide forming species, wherein the metal hydroxide forming species comprises an oxide or hydroxide of a metal to be recovered from the raw material,
wherein the lixiviant solution is formulated to transfer a first member of the pair of zwitterions to the metal hydroxide forming species while forming a partially uncharged second member of the pair of zwitterions, and wherein the partially uncharged second member of the pair of zwitterions is formulated to react with an acid to regenerate the first member of the pair of zwitterions.
2. The mixture of claim 1 , wherein the zwitterion species complex is present at substoichiometric quantities relative to the metal hydroxide forming species.
3. The mixture of claim 1 , wherein the zwitterion species is an amine containing acid.
4. The mixture of claim 3 , wherein the zwitterion species is selected from the group consisting of an amino acid and 3-aminopropanoic acid.
5. The mixture of claim 1 , wherein the zwitterion species is a chelating agent.
6. The mixture of claim 5 , wherein the zwitterion species is selected from the group consisting of ethylenediaminetetraacetic acid and salts thereof, ethylene glycol tetraacetic acid and salts thereof, diethylene triamine pentaacetic acid and salts thereof, and 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid and salts thereof.
7. The mixture of claim 1 , wherein the zwitterion species is selected from the group consisting of a betaine, an ylide, and a polyaminocarboxylic acids.
8. The mixture of claim 1 , wherein the first member of the pair of zwitterions and the second member of the pair of zwitterions are the same compound.