Abstract: An oil desulfurization method may be used to desulfurize various oils, such as used motor oil, crude oil, diesel, high sulfur fuel oil, mid sulfur fuel oil, off-spec fuel oil, and off-spec diesel, to produce a finished product of lower sulfur oil and a high sulfur fuel oil or sulfur containing oil product. Preferably, the method may include the steps of: mixing an oxidizing material with sulfur containing oil to produce a first mixture; subjecting the first mixture to at least one of heat and pressure to oxidize the sulfur in the first mixture; mixing at least one solvent with the first mixture to produce a second mixture; and separating the second mixture to produce a low sulfur oil product and a third mixture, the third mixture having a high sulfur oxidized oil and the at least one solvent.

Abstract: An apparatus and method for separating hydrophilic particles from a fluid suspension containing both hydrophilic and hydrophobic particles. A generally cylindrical separation vessel includes tangential inlet and outlet ports. The fluid suspension is introduced into the separation vessel through the inlet port to circulate around the inner surface of the separation vessel in a forced vortex swirl flow. Air sparged through a porous wall portion of the side walls of the separation vessel forms air bubbles to which attach hydrophobic particles in particle/bubble aggregates. These migrate as a froth towards the axial center of the separation vessel where they are discharged at the upper end thereof. A froth washing tube having an open end proximate to the upper end of the separation vessel discharges pressurized water thereinto.