Porous polyfluoroalkylene sheet useful for separating anolyte from catholyte in electrolytic cells
US4292146A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1979 |
| Grant date | Sep 29, 1981 |
| Priority date | — |
| Expiry date | Aug 7, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25B13/08
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A porous polyfluoroalkylene sheet, very preferably of polytetrafluoroethylene, which is suitable for use as a separator in an electrolytic cell, such as one used for the electrolysis of brine, has a porosity in the range of 70 to 90%, a thickness in the range of 0.2 to 3.5 mm. and at least one of (a) an A X-ray ratio in the range of 0.1 to 0.35 and (b) a B X-ray ratio in the range of 0.75 to 0.98. Preferably the A X-ray ratio is in the range of 0.1 to 0.3, the B.sub.2 X-ray ratio is in the range of 0.75 to 0.98 and the B.sub.1 X-ray ratio is in the range of 0.1 to 0.32. The porous sheets are separators or diaphragms for electrolytic cells and the uses of such separators and cells in electrolysis processes, preferably in the electrolysis of brine, are described. Also known in the specification are a method for the manufacture of the porous sheets and a method for ascertaining which milled, sintered and leached porous sheets are more suitable for use in electrolytic processes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.