Investigation of the In-Situ Oxidation of Methanol in Fuel Cells.
Abstract
Direct anodic oxidation and internal reforming were examined as ways of using methanol as fuel in a phosphoric acid fuel cell. The literature was reviewed to identify the most effective catalysts for the direct electrochemical oxidation of methanol. It was shown experimentally that, even with the best of these catalysts, anode polarization at practical current densities is 300 mV higher on methanol than on hydrogen. It was also found that unreacted methanol which diffuses across the cell can cause severe polarization of the cathode. Theoretical and experimental studies of internal reforming showed that a fuel cell will generate sufficient waste heat to sustain the methanol-steam reforming reaction. Thus, thermally-integrated, internal reforming is a feasible alternative to external reforming. The reforming catalyst is preferably located in separate chambers built into the stack, since this prevents phosphoric acid from attacking the reforming catalyst and methanol from migrating to the cathode. A 2-in. by 2-in. fuel cell, running on the gaseous product from a subscale reformer operating at 400 F, gave 0.624 volts at 200 ASF (85% methanol/50% air utilization). From the standpoint of efficiency, internal reforming is superior to direct oxidation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1981
- Accession Number
- ADA105947
Entities
People
- D. A. Landsman
- F. J. Luczak
Organizations
- United Technologies Corporation