Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4847018 | Process for producing petroleum sulfonates | Jeffery W. Koepke, Wen-Ching Hsieh | 1989-07-11 |
| 4446036 | Process for enhanced oil recovery employing petroleum sulfonate blends | Wen-Ching Hsieh, Jeffery W. Koepke | 1984-05-01 |