Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5133846 | Silver recovery device | Marc De Niel, Herman M. Engels, Marc Scheerders, Dirk De Ruijter, Benedictus Jansen | 1992-07-28 |
| 5118402 | Electrolytic silver recovery system for recovering silver from photographic fixing solutions | Herman M. Engels, Marc De Niel | 1992-06-02 |