A process is disclosed for producing at least one high purity aromatic carboxylic acid by oxidizing an aromatic feedstock with oxygen in a reaction medium comprising the aromatic feedstock, a promoter, a heavy metal catalyst, and a solvent which comprises benzoic acid and water to produce a reactor effluent wherein substantially all of the aromatic carboxylic acid produced remains in solution; and then hydrogenating the reactor effluent in the presence of a catalyst and hydrogen. This process efficiently and effectively produces high purity aromatic carboxylic acids by utilizing a common solvent for both oxidation and purification and eliminating the need for intermediate process steps and equipment.