(193f) Development of a High-Efficiency Hydrogen Generator Based On Adsorption Enhanced Pulsing Feed Reforming
A collaborative effort between Intelligent Energy and Cal Poly Pomona has developed an adsorption enhanced reformer (AER) for hydrogen generation for use in conjunction with fuel cells in small sizes. The AER operates at a lower temperature (about 500 °C) and has a higher hydrogen yield and purity than those in the conventional steam reforming. It employs ceria supported rhodium as the catalyst and potassium promoted hydrotalcites to remove carbon dioxide from the products. A novel pulsing feed concept is developed for the AER operation to allow a deeper conversion of the feedstock to hydrogen. The bed is regenerated using either steam or cathode off-gas from the fuel cell before the next production cycle. With four packed beds running alternately, fuel cell grade hydrogen gas and CO2 rich regeneration exhaust exit the reactor separately, which avoids the use of PSA for hydrogen purification. In the best case of methane reforming, the yield of hydrogen in the product gas is about 66% while the carbon dioxide and carbon monoxide concentrations are on the ppm level. If accounting for hydrogen in the regeneration exhaust, the overall hydrogen yield is 92%.