Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4869804 | Process for the thermal conversion of heavy petroleum fractions and refining residues, in the presence of oxygen compounds of sulfur and nitrogen and compositions containing these compounds | Pierre Le Perchec, Beatrice Debled, Michel Thomas | 1989-09-26 |