Abstract: The invention of the current application is directed to a wastewater treatment apparatus. The invention includes a divided membrane electrochemical cell including an anode contained within a anode compartment and cathode contained within a cathode compartment. The anode compartment and said cathode compartment are separated by a proton selective membrane. The invention also includes a voltage source, and a liquid-gas separator. The invention is an economically viable electrochemical advanced oxidation system that can cost-effectively treat recalcitrant COD with low energy, without the necessity for chemicals, and reduce or prevent sludge production in a single step.