Hydrocarbon and sulfide removal in direct aqueous extraction
Methods of treating an aqueous source are described herein that include reducing a concentration of sulfide species in a stream obtained from the aqueous source to form an extraction feed and extracting ions from the extraction feed, or a stream obtained from the extraction feed, using direct aqueous extraction. Other methods describe treating an aqueous source by reducing a concentration of organic species in a stream derived from the aqueous source to form an extraction feed and extracting ions from the extraction feed, or a stream derived from the extraction feed, using direct aqueous extraction. The aqueous source can be an aqueous lithium source.
1. A method of recovering ions from an aqueous source, comprising:
reducing a concentration of sulfide species in a stream obtained from the aqueous source to form an extraction feed;
extracting target ions from the extraction feed, or from a stream derived from the extraction feed, using direct aqueous extraction in an extraction stage to yield an extract; and
reducing a concentration of dissolved silica, in the aqueous source, the stream obtained from the aqueous source, the extraction feed, or any combination thereof.
2. The method of claim 1 , further comprising reducing a concentration of organic species in the aqueous source, extraction feed, or any combination thereof.
3. The method of claim 1 , wherein reducing the concentration of sulfide species comprises:
displacing the sulfide species using a gas,
oxidizing the sulfide species using a chemical or biological agent that reacts with the sulfide species,
withdrawing the sulfide species using withdrawal material in an adsorption-desorption process,
or a combination thereof.
4. The method of claim 1 , where the sulfide species is chemically converted to a reagent and the reagent is recycled.
5. The method of claim 4 , wherein the reagent is used to adjust pH of the extraction feed, the stream derived from the extraction feed, or both.
6. A method of recovering ions from an aqueous source, comprising:
removing suspended solids from, and then reducing a concentration of sulfide species in a stream obtained from the aqueous source to form an extraction feed; and
extracting target ions from the extraction feed or from a stream derived from the extraction feed, using direct aqueous extraction in an extraction stage to yield an extract.
7. A method of recovering lithium from an aqueous source, comprising:
reducing a concentration of organic species in a stream obtained from the aqueous source to form an extraction feed;
extracting target ions from the extraction feed, or from a stream obtained from the extraction feed, using direct aqueous extraction in an extraction stage to yield an extract; and
reducing a concentration of dissolved silica, in the aqueous source, the stream derived from the aqueous source, the extraction feed, or any combination thereof, wherein the target ions include lithium ions.
8. The method of claim 7 , wherein reducing the concentration of the organic species comprises using gravity separation, electrochemical separation, chemical treatment, bacterial treatment, gas flotation, filtering, inducing coalescence and adsorption-desorption, or any combination thereof.
9. The method of claim 7 , wherein the organic species includes non-dissolved organics and reducing the concentration of non-dissolved organics uses a gravity separation process, a filtering process, a gas flotation process, or a combination thereof.
10. The method of claim 7 , wherein the organics species includes dissolved organic materials and reducing the concentration of dissolved organics includes using organic selective media.
11. The method of claim 7 , wherein reducing the concentration of organic species includes using granular activated carbon (GAC) in a filtering process, a counter-current adsorption desorption (CCAD), or both.
12. The method of claim 7 , further comprising:
reducing a concentration of sulfide species in the extraction feed to yield the stream derived from the extraction feed.
13. The method of claim 7 , further comprising concentrating a stream derived from the extract in a concentration stage to yield a concentrate.
14. The method of claim 7 , further comprising routing the extract, a stream derived from the extract, or both, to an impurity removal stage to reduce concentration of one or more hardness species, one or more transition metals, one or more divalent impurities, monovalent impurities or a combination thereof.
15. The method of claim 7 , wherein the target ions further include cobalt ions, nickel ions, manganese ions, magnesium ions, potassium ions, copper ions, iron ions, zinc ions, aluminum ions, molybdenum ions, vanadium ions, or a combination thereof.
16. The method of claim 1 , wherein the target ions include lithium ions, cobalt ions, nickel ions, manganese ions, magnesium ions, potassium ions, copper ions, iron ions, zinc ions, aluminum ions, molybdenum ions, vanadium ions or a combination thereof.
17. The method of claim 1 , further comprising concentrating a stream derived from the extract in a concentration stage to yield a concentrate.
18. The method of claim 1 , further comprising routing the extract, a stream derived from the extract, or both, to an impurity removal stage to reduce concentration of one or more hardness species, one or more transition metals, one or more divalent impurities, monovalent impurities or a combination thereof.