Permeable membrane diaphragm of different layers for electroytic cells
US7241367B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 21, 2000 |
| Grant date | Jul 10, 2007 |
| Priority date | — |
| Expiry date | Jan 21, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/36
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The present invention relates to a permeable membrane diaphragm of different layers for electrolytic cell, especially for chloro-alkali electrolytic cell. The diaphragm is asymmetric, which comprises at least two layers: a flow-controlling permeable layer comprising micro-porous fluoropolymer, especially PTFE, and a diffusion-restricting permeable layer comprising porous film, sheet or cloth made of anticorrosive materials, preferably polypropylene. The flow-controlling layer is mounted near the anode, and the diffusion-restricting layer is mounted near the cathode. The mean pore diameter of the diffusion-restricting layer is at least 5 times more than that of the flow-controlling layer and the thickness of the diffusion-restricting layer is at least 1 times more than that of the flow-controlling layer. The pore diameter of said flow-controlling layer ranges from 0.1–2.0 μm, and its thickness is 0.03–0.2 mm. The pore diameter of said diffusion-restricting layer ranges from 5–50 μm, and its thickness is 0.3–2 mm. The above two layers can also be made of more than one similar thinner membranes respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.