Method for recycling scrapped polyvinylidene fluoride (PVDF) membrane produced in water treatment
US12121837B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 2021 |
| Grant date | Oct 22, 2024 |
| Priority date | — |
| Expiry date | Jun 2, 2043 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/62
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method for recycling a scrapped polyvinylidene fluoride (PVDF) membrane through chemical cleaning-structural transformation-hydrophilicity is disclosed, which can extend the service life of scrapped PVDF membrane materials (namely, membrane at the end of service life). The method includes the following steps: cleaning a scrapped membrane with sodium hypochlorite and citric acid; treating the membrane with a structural transformation agent, where, irreversible contaminants are washed away while the PVDF membrane is subjected to pore expansion and hydrophilization; and with self-polymerization of dopamine on a membrane surface, further improving the hydrophilicity of the membrane surface, enhancing the anti-contamination performance, and repairing damaged points on the surface of the scrapped PVDF membrane produced during long-term operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.