Process for the recovery of zinc from zinc- and iron-containing materials
Abstract
Abstract A PROCESS FOR THE RECOVERY OF ZINC FROM MATERIALS, E.G. ORES OR CONCENTRATES AND OTHER SUBSTANCES CONTAINING ZINC AND IRON, GENERALLY IN THE FORM OF OXIDES, WHEREIN THE MATERIAL IS LEACHED WITH EXCESS HOT SULFURIC ACID. THE ACIDITY OF THE EXTRACTS IS REDUCED BY ADDING ZINC OXIDE OR LIKE ZINC-CONTAINING OXIDIC MATERIALS TO PRECIPITATE IRON. THE LEACHING IS CARRIED OUT AT 95*-100*C. WITH A LEACHING SOLUTION CONTAINING 180-220 G./LITER H2SO4. LEACHING IS CONTINUED UNTIL THE SULFURIC ACID CONTENT IS REDUCED TO 20-60 G./LITER H2SO4, WHEREUPON THE ZINC-CONTAINING OXIDIC MATERIALS ARE ADDED, PREFERABLY SUBSEQUENT TO THE ADDITION OF ALKALI-METAL AND/OR AMMONIOM IONS, AT A TEMPERATURE OF 95*-100*C. TO REDUCE THE SULFURIC ACID CONCENTRATION TO LESS THAN 10 G./LITER H2SO4.
Inventors
- 👤 Adolf Von Roepenack
- 👤 Hans Wuetrich
- 👤 Wilhelm Schmidt
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-12 | 1976-03-13 | 1976-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-12 | 1980-03-13 | 1980-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-12 | 1984-03-13 | 1984-09-12 | $7700.00 | Window Closed / Lapsed |