| It is proposed to study and optimize the operation of a hybrid-sulfur type electrolyzer for the efficient production of clean hydrogen. The goal of this work is to understand the parameters that affect electrolyzer efficiency, leading to better designs and a higher current efficiency for hydrogen production. Performance has been evaluated from polarization data. The concentration of sulfuric acid byproduct and production rate have been measured to determine the rate at which sulfuric acid may be sent back to the thermal decomposition unit. The effect of temperature has been measured by varying the temperature from ∼60°C to ∼90°C for the proton exchange membrane (PEM) electrolyte.;Realizing that water management is an important aspect of electrolyzer performance because it affects sulfuric acid concentration and thus cell voltage, a mathematical model has been developed to determine the effects of operating and design parameters on water transport. The model has been extended to determine the effects of water transport on SO2 crossover to the cathode.;Further addressing the problem of SO2 crossover to the cathode, alternative PEM electrolytes have been developed at Sandia National Laboratories. These membranes have been optimized to resist sulfur dioxide crossover, and have been tested in our electrolyzer system. |
