Process for purifying phosphorus pentafluoride
US9975771B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2014 |
| Grant date | May 22, 2018 |
| Priority date | — |
| Expiry date | Jan 8, 2035 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/10
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for obtaining high-purity phosphorus pentafluoride (PF5), which is industrially useful in the fields of semiconductors and batteries, from PF5 containing a gas mixture of HCl, HF, and so on. Specifically, provided is a process for purifying phosphorus pentafluoride including (1) an immobilization step in which phosphorus pentafluoride containing a mixture is brought into contact with a metal fluoride (MFn; M is an n-valent metal) having a specific surface area of 1.0 m2/g or more at 40° to 150° C. to immobilize phosphorus pentafluoride in the form of a hexafluorophosphate (M(PF6)n), (2) a separation step in which the mixture remaining in the gas phase is expelled out of the reaction system to separate the mixture from the hexafluorophosphate, and (3) a heat-decomposition step in which the hexafluorophosphate freed of the mixture is heated at 150° to 400° C. under a pressure of −0.1 to 0.1 MPa·G to give phosphorus pentafluoride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.