Lithium extraction composition and method of preparation thereof
This invention relates to a particulate extraction material for the extraction of lithium from a geothermal brine or lithium containing solution. The particulate material includes an inorganic or polymer based substrate that includes a lithium aluminate intercalate layer applied to the exterior of the substrate, wherein the lithium aluminate intercalate layer is operable to capture lithium ions from solution.
1. A composition for the recovery of lithium from a lithium containing solution comprising:
a porous membrane containing lithium aluminate intercalate, wherein the lithium aluminate intercalate is deposited into the membrane by contacting a polyaluminum hydroxyl halide solution and the membrane in the presence of lithium salt, thereby integrating the lithium aluminate intercalate into the membrane.
2. The composition of claim 1 , wherein the membrane is a polymeric membrane.
3. The composition of claim 1 , wherein the membrane is an inorganic membrane.
4. The composition of claim 1 , wherein the polymeric membrane has an average pore size of less than about 5 μm.
5. The composition of claim 1 , wherein the ratio of aluminum to lithium is between about 1:0 and 1:0.6.
6. The composition of claim 1 , wherein the lithium salt is lithium hydroxide.
7. The composition of claim 1 , wherein the lithium salt is lithium chloride.
8. A method for preparing a composition for the recovery of lithium from a lithium containing solution, wherein the method comprises the steps of:
providing a porous membrane;
contacting the porous membrane with polyaluminum hydroxyl halide to form an alumina integrated porous membrane; and
intercalating a lithium salt into the alumina layer on the porous membrane to form a lithium aluminate intercalate.
9. The composition of claim 8 , wherein the porous membrane is a polymeric membrane.
10. The composition of claim 8 , wherein the porous membrane is an inorganic membrane.
11. The method of claim 8 , wherein the porous membrane is a resin-based membrane.
12. The method of claim 8 , wherein the polyaluminum hydroxyl halide has a general formula, Al/(OH) a (X) b , wherein the halide X is selected from the group consisting of fluoride, bromide, chloride and iodide, and wherein a and b are each between about 0.5-5.5, and wherein the sum of a and b is 6.
13. The method of claim 8 , wherein a is between about 3 and 6 and b is between about 0.5 and 3, and wherein the sum of a and b is 6.
14. The method of claim 8 , wherein the halide is chlorine.
15. The method of claim 8 , wherein the lithium salt intercalated into the polyaluminum hydroxyl chloride coating is lithium chloride.
16. The method of claim 8 , wherein the step of intercalating the lithium salt into the polyaluminum hydroxyl halide coating comprises the steps of:
contacting the polyaluminum hydroxyl halide coating with an alkali hydroxide, and
then optionally contacting the coating with the lithium salt.
17. A method for removal and recovery of lithium from a lithium containing solution, comprising the steps of:
contacting the lithium containing solution with a porous membrane, said porous membrane having a lithium aluminate intercalate layer, wherein the step of contacting the lithium containing solution and the porous membrane with the lithium aluminate intercalate layer results in the removal of at least a portion of the lithium present in the lithium containing solution and the capture of said lithium by the porous membrane with the lithium aluminate intercalate layer; and
recovering the captured lithium by washing the porous membrane with the lithium aluminate intercalate layer with a wash water.
18. The method of claim 17 , wherein said wash water has a lithium concentration of less than about 200 ppm.