Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4834951 | Common separation of contaminating elements from electrolyte solutions of valuable metals | Ralf Kehl | 1989-05-30 |
| 4820417 | Use of citric acid partial esters for the extraction of iron | Willi Buchmeier, Ralf Kehl | 1989-04-11 |