Modeling of Natural Gas Steam Reforming Process in a Pd/Ag Membrane Reactor for Pure Hydrogen Production

Fuel cells will be one of the most important resources of energy in the future They use pure hydrogen, and natural gas as a feed. Converting chemical energy to electrical energy in fuel cells is a direct process without any environmental pollution. Thus the study and modeling of various hydrogen production and purification processes is necessary. Up to day, natural gas steam reforming is one of the most important chemical processes for hydrogen production. It should be mentioned that hydrogen is obtained from a produced synthesis gas (product of methane steam reforming process). A lot of researches have also done work on a direct production of pure hydrogen using various membranes. Previous studies have shown that using Pd-Ag membrane is only permeable for hydrogen is the best choice for pure hydrogen production. Thus, in the present study the modeling of natural gas steam reforming in the Pd-Ag membrane reactor has been done. Effect of some variables such as pressure, temperature, steam to methane ratio in the feed, membrane thickness and flow pattern of reactants and sweep gas on the methane conversion, hydrogen production and produced hydrogen-to-carbon monoxide ratio have been investigated and optimum operating conditions have been determined qualitatively. The proposed model has been evaluated by some data that obtained from an experimental study. The results of the proposed model have a good consistency with the results of experimental study.