| abstract |
A process for purifying a dicarboxylic acid that is derived from the mixed oxidation products from an ozonization of a mixture containing an ethylenically unsaturated compound having between 6 to 24 carbons, the process includes distilling the mixed oxidation products to provide a first distillate, and a second distillate, where the second distillate includes the dicarboxylic acid and impurity acids, partitioning the second distillate between water and a organic solvent, separating the organic solvent layer from the water layer, lowering the temperature of the water layer to crystallize at least a portion of the dicarboxylic acid, separating the crystallized dicarboxylic acid solid, melting the crystallized dicarboxylic acid, and distilling the liquid dicarboxylic acid to provide a purified dicarboxylic acid. |