Thermo-chemical extraction of fuel oil from waste lubricating grease

► Two stage flocculation extraction of base oil from used grease. ► 15% hot potassium hydroxide (KOH) solution is used to degrade grease at high shear agitation and extracts up to 49% oil. ► Toluene is used to further extracts 26% remaining oil thus less solvent is used for extraction. ► The mass of waste grease is reduced by 75% resulting in fuel oil production. ► KOH solution degrades the grease matrix and separates the thickener from the base oil.