Fuel Gore-Select

FIGURE 27.37 Fabrication scheme of Gore-Select described in U.S. Patent 5,547,551. (Reproduced fromNakao, M. and Yoshitake, M., in W. Vielstich, H.A. Gasteiger, and A. Lamm (Eds.), Handbook of Fuel Cells Fundamentals, Technology and Applications, Vol. 3, J. Wiley Sons, Chichester, 2003. With permission.)... 

Gore-Select membrane is a recent innovation that is useful for fuel cells. The membrane is made by filling the pores of Gore-Tex (expanded PTFE) with a per-fluorinated ionomer Hke Nafion. The resulting membrane is about 20 pm thick, about one tenth the thickness of a Nafion membrane, and it has about half the resistance of Nafion. Membrane-electrode assembhes are made by applying platinum black coatings (0.3 mg/cm ) to both surfaces. They are reported to perform well in fuel cells [46]. 

Fig. 4 Comparison of Nafion-112 and GORE-select membrane 25 mm based MEAs Polarization performance and difference in polarization performance in cells operated with either dry or 100% RH cathode humidification (1(X)% RH anode in both experiments). General Motors (GM) Global Alternative Propulsion Center (GAPC) 500 cm fuel cell stack at cell temperature 80°C, hydrogen and air reactants at 2.0x stoichiometric flow and 270 kPa operating pressure (from Cleghorn et al., 2003).

Perfluorinated membranes reinforced with woven PTFE, such as Nafion 324 or Nafion 417, are used in many industrial electrochemical processes. Unfortunately, the relatively coarse weave of the woven PTFE reinforcement results in membranes that are much too thick for high electrochemical performance. Some non-woven PTFE/perfluorinated ionomer composite membranes have been formulated for ion transport studies and for investigation of other properties relevant to chlor-alkaU and fuel cell applications. Advancements in materials and processing technology have resulted in the introduction of PTFE/perfluorinated ionomer composite membranes claimed by Gore and Associates, Inc. under the Gore Select trademark. Most types of ion exchange membranes contain some type of reinforcement because they are weak and tend to swell substantially as they incorporate a solvent onto their structure. This reinforcement can be a macro reinforcement or a micro reinforcement . 

Bonde, S.E. Gore, W. Dolbear, G.E. Skov, E.R. Selective oxidation and extraction of suUur-containing compounds to economically achieve ultra-low proposed diesel fuel sulfur requirements. Prep. Div. Pet Chem., American Chemical Society, 219 National Meeting, San Francisco, CA, March 26-31,2000 364-366. 

Bonde, S. E. Gore, W. Dolbear, G. E. Skov, E. R. Selective Oxidation and Extraction of Sulfur-Containing Compounds to Economically Achieve Ultra-Low Diesel Fuel Sulfur Requirements. Am. Chem. Soc. Div. Petrol. Chem. Prep., 2000,45, 364-366. 

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