Patent ID: 8703993

Claim:
A process for preparing an alpha, omega-dicarboxylic acid or an ester thereof, the process comprising: (a) preparing a solution of at least one unsaturated fatty acid or fatty acid derivative in an aliphatic carboxylic acid and water mixture wherein the content of water is at least a stoichiometric amount of water relative to the number of double bonds of the fatty acid or fatty acid derivative to be oxidized; (b) subjecting the unsaturated fatty acid or fatty acid derivative solution to ozonolysis to obtain an ozonolysis reaction mixture; (c) adding a catalytic amount of an acid having a pKa of less than or equal to zero, measured at 25° C., to the ozonolysis reaction mixture following completion of the ozonolysis without workup; and (d) oxidizing the ozonolysis reaction mixture with an oxidizing agent to obtain an oxidized reaction mixture comprising at least one alpha, omega-dicarboxylic acid or ester thereof; wherein the acid with a pKa of less than or equal to zero, measured at 25° C., comprises at least one selected from the group consisting of sulphuric acid, hydrochloric acid, nitric acid and perchloric acid.