Anion removal from waste water
US10822253B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 2019 |
| Grant date | Nov 3, 2020 |
| Priority date | — |
| Expiry date | Sep 6, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2303/16
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
Methods for removing anions from an aqueous solution include contacting the aqueous solution with an initial organic phase composition in a primary stage to form a first mixture, the initial organic phase composition including a quaternary amine and a weak organic acid; separating a nitrate-depleted raffinate from the first mixture; mixing the remaining organic phase (now containing nitrate) with a first basic solution to obtain a second mixture; separating an aqueous phase sulfate-containing scrub solution from the second mixture; mixing the remaining organic phase with a second basic solution to form a third mixture; and separating the third mixture into an aqueous phase nitrate-rich solution and a secondary organic phase composition. The secondary organic phase composition can be recycled. The raffinate, the sulfate-containing scrub solution, and the nitrate-rich solution can then be further processed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.