Method for concentrating and purifying eluate brine for the production of a purified lithium compound
US12258280B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 9, 2020 |
| Grant date | Mar 25, 2025 |
| Priority date | — |
| Expiry date | Mar 13, 2042 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W10/37
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method is disclosed for concentrating and purifying an eluate brine and producing a purified lithium compound. An extraction eluate, rich in lithium, is directed to a nanofiltration unit or a softening process that removes sulfate and/or calcium and magnesium. Permeate from the nanofiltration unit or the effluent from the softening process is directed through an electrodialysis unit. As the lithium-rich solution moves through the electrodialysis unit, lithium, sodium and chloride ions pass from the solution through a cation-transfer membrane and an anion-transfer membrane to concentrate compartments. A dilute stream is directed through the concentrate compartments and collects the lithium, sodium and chloride ions. The electrodialysis unit also produces a product stream which contains non-ionized impurities, such as silica and/or boron. Concentrate from the electrodialysis unit is subject to a precipitation process that produces a lithium compound that is subsequently subjected to a purification process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.