Abstract: An improved apparatus and method is disclosed utilizing hydrogen absorption in combination with photolysis and/or electrolysis for in situ generation, i.e., without the need for adding chemical oxidizing agents, or enhancement of oxidizing conditions used to promote oxidation of organic compounds to form carbon dioxide, and the use of the same in connection with high-accuracy determination of even extremely low levels of organic and/or inorganic carbon compounds both in flowing aqueous streams and in bulk solutions.

Abstract: An oxidation reactor having particular utility in a system for measuring carbon in an aqueous sample. A first chamber and second chamber are separated by a hydrogen-permeable electrode, each chamber having a separate electrolysis cell. The hydrogen-permeable electrode acts as the anode of one cell and the cathode of the other cell. The sample stream flows into one chamber and the electrolysis cell produces oxygen from the water at one optically transparent electrode and in combination with short wave ultraviolet light oxidizes organic carbon to CO.sub.2 and produces hydrogen at the other electrode which passes through the hydrogen-permeable electrode into the second chamber. The electrolysis cell in the second chamber produces oxygen at hydrogen-permeable electrode to react with the hydrogen that passes through the hydrogen-permeable electrode to form water, thereby maintaining the maximum concentration gradient of hydrogen across the hydrogen-permeable electrode to improve hydrogen transferring efficiency.