Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4960461 | Method and installation for extracting gold from gold ore | Hans Kellerwessel, Ludwig Gemmer, Gert-Helge Hamacher | 1990-10-02 |
| 4477323 | Method for recovering zinc from a sulfidic zinc source | Hermann Hilbrans | 1984-10-16 |
| 4248628 | Method for leaching and precipitating metal values from solids | — | 1981-02-03 |