Synthesis of stable solutions of rare earth tris (organophosphate) in hydrocarbon solvents
US6767927B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2000 |
| Grant date | Jul 27, 2004 |
| Priority date | — |
| Expiry date | Apr 25, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07F9/025
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Stable rare earth tris (organophosphate) solutions comprise a rare earth tris (organophosphate) and a hydrocarbon solvent. From about 2% to about 10% rare earth element, preferably from about 3% to about 8%, is present in the solutions. The rare earth tris (organophosphate) solutions are stable from precipitation of the rare earth tris (organophosphate) for at least about fifteen (15) days, preferably for at least about twenty (20) days and most preferably at least about thirty (30) days. A process for preparing these solutions is described herein. A stabilizing additive, acid, glycol or mixtures thereof, is utilized to inhibit precipitation. The molar ratios of free acid, glycol and/or water to the rare earth element are controlled to inhibit precipitation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.