|
| US4046668 | 12 Jan 1976 | 6 Sep 1977 | Mobil Oil Corporation | Double solvent extraction of organic constituents from tar sands |
| US4057486 | 14 Jul 1975 | 8 Nov 1977 | Canadian Patents and Development Limited | Separating organic material from tar sands or oil shale |
| US4067796 | 27 May 1975 | 10 Jan 1978 | Standard Oil Company | Tar sands recovery process |
| US4229281 | 14 Aug 1978 | 21 Oct 1980 | Phillips Petroleum Company | Process for extracting bitumen from tar sands |
| US4448667 | 20 Dec 1982 | 15 May 1984 | Dravo Corporation | Process for solvent extraction of bitumen from oil sand |
| US4722782 | 31 Oct 1983 | 2 Feb 1988 | Standard Oil Company | Method for solvent treating of tar sands with water displacement |
