Method of regenerating etchant and recovering etched metal
US4329210A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1980 |
| Grant date | May 11, 1982 |
| Priority date | — |
| Expiry date | Mar 28, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of regenerating etchant and recovering etched metals. Etching solution, which is overladen with metal cations is passed through a cation exchange unit. Subsequently, the etching solution, which is diminished in metal cation concentration, is returned to the etcher sump. The cation exchange unit is then rinsed with deionized water to remove residual etching solution, with the effluent being conveyed to a metal recovery unit. The cation exchange unit is then rinsed with an aqueous solution of an acid to remove cations and to regenerate the cation exchange unit. The effluent from this rinsing is also conveyed to the metal recovery unit. The cation exchange unit is then rinsed with deionized water to remove residual acid, with this effluent likewise being conveyed to the metal recovery unit. Subsequently, a selectolyte solution is passed through the cation exchange unit to enhance the cation retention property thereof. The effluent is conveyed to a storage container. At this point, etched metal can be recovered from the metal recovery unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.