Method for obtaining alkali metal salt aqueous solution of aromatic dihydroxy compound from waste aromatic polycarbonate
US7750057B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 20, 2005 |
| Grant date | Jul 6, 2010 |
| Priority date | — |
| Expiry date | Nov 19, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/62
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
There is provided a method for obtaining an aqueous solution of an alkali metal salt of an aromatic dihydroxy compound by decomposing a waste aromatic polycarbonate by an alkali metal hydroxide aqueous solution. The method comprises (1) a dissolution step of dissolving a waste aromatic polycarbonate in a chlorinated hydrocarbon solvent, (2) a decomposition step of adding an alkali metal hydroxide aqueous solution to this solution to decompose the aromatic polycarbonate, (3) a re-dissolution step of adding water to this decomposed solution to dissolve a solid, (4) a two phase formation step of leaving the treated solution obtained in the step (3) to stand to form an organic solvent phase (organic phase) and an aqueous solution phase (aqueous phase), and (5) a separation/collection step of separating the aqueous phase from the organic solvent phase and collecting the aqueous phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.