Treatment of Low Concentration Hydrogen by use of Proton Exchange Membrane

Proton exchange membrane fuel cell (PEMFC) can hardly react a hundred percent of fuel, because a cell potential becomes zero if all of the fuel is consumed at PEMFC. Therefore a small amount of fuel is always released from PEMFC. The exhausted H2 should be treated for safety. iave-Vcel characteristics were measured changing hydrogen concentration from 99.99% to 1%. Moreover, Vcell of the constant voltage control was selected from the measured Vcell-iave characteristics, the low concentration hydrogen could be treated under Vcell =0.15 - 0.3V by hydrogen pump and Vcell =0.4 - 0.6V by PEMFC. The exhaust hydrogen was reduced to the hydrogen concentration of several tens of ppm.