The relative humidity (RH) readings of the effluents from the anode and cathode were converted to mole fractions in each stream, xw through global mass balances (Eq. (2)). Themolar flow rates of the feed are Fin(mol/s), iH+ is the cell current(amp), F is Faraday’s constant (coulomb/mol), and , iH+ is the fraction of water that exits in the anode effluent (the water is formed at the cathode and must diffuse through the membrane to be transferred to the anode effluent).