Patent ID: 7161017

Claim:
A process for producing unsaturated and saturated free fatty acids, the process comprising the steps of: a) selecting a starting material from the group consisting of trap oils, trap greases, brown greases, and grease trap waste; b) pretreating the oils and/or greases selected in step a) in order to separate the oils and/or greases from water and obtain a mixture of saturated, unsaturated free fatty acids and impurities; c) subjecting the mixture obtained in step b) to a first purification step by fractionating the mixture obtained in step b) in three fractions: a light fraction principally constituted of volatile compounds and water, an intermediate fraction mainly constituted of free fatty acids, and a residual heavy fraction mainly constituted of poly-glycerides and polymers; d) fractionating the free fatty acids fraction in two fractions: saturated fatty acids (SFA) and unsaturated fatty acids (UFA); and e) subjecting the saturated fatty acids and unsaturated fatty acids to a second purification step in order to obtain oleic acid and stearin and their respective unsaturated and saturated fatty acid residues.