Patent ID: 10883055

Abstract:
A method for selective extraction of naphthenic acids from an acidic crude oil, including: providing an acidic crude oil including naphthenic acids and having a total acid number (TAN) greater than 0.4; mixing the acidic crude oil with a first aqueous solution including water and a weak base to extract a portion of naphthenic acids from the acidic crude oil thereby creating a second aqueous solution containing a mixture of the portion of naphthenic acids, the water and the weak base in an emulsion; separating the second aqueous solution from the emulsion; wherein the second aqueous solution contains an additional portion of the acidic crude oil; adding a salt to the second aqueous solution, thereby causing the additional portion of the acidic crude oil to separate from the second aqueous solution; removing the additional portion of the acidic crude oil from the second aqueous solution; and extracting the portion of the naphthenic acids from the second aqueous solution.