Process for recovering quaternary salt bromination catalyst
US11786891B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 2022 |
| Grant date | Oct 17, 2023 |
| Priority date | — |
| Expiry date | May 19, 2042 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/584
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Quaternary ammonium tribromides and quaternary phosphonium tribromides are recovered from an organic solvent by washing with an aqueous hydrazine solution. The hydrazine reacts to form nitrogen, hydrobromic acid and a quaternary ammonium or quaternary phosphonium monobromide. The hydrobromic acid and quaternary ammonium or quaternary phosphonium migrate to the aqueous phase, thereby effecting the removal of the tribromides from the organic solvent. The hydrobromic acid can be neutralized with a quaternary ammonium or quaternary phosphonium hydroxide to produce a quaternary ammonium or quaternary phosphonium monobromide. The monobromides produced can be reacted with elemental bromine to regenerate a tribromide brominating agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.