Fuel processing for pem fuel cells: In-line adsorbent filters for MEA protection

The present work deals with hydrogen generation from JP8 reformation and clean-up of the reformate to produce PEMFC quality hydrogen. The fuel processor has reformer, post-former, water gas shift reactors, H ₂S removal, preferential CO oxidation, and CO ₂ removal stages. The processor also incorporates a final adsorbent fuel filter that can efficiently remove ppm level impurities that may poison the fuel cell catalyst. High contacting efficiency microfibrous media are used to entrap various reactive materials including heterogeneous catalysts and sorbents. These media are then layered so as to permit multiple staged chemical reactions to be achieved within the space of a few millimeters of thickness. As an example of this generic approach, microfibrous entrapped media containing sorbents to remove H ₂S, NH ₃, CO, and CO ₂ were sequentially layered. The enabling attribute is the high contacting efficiency afforded by microfibrous entrapment, and the thin layer design of these materials that permit facile and effective layering, packaging and sealing.