| 초록 |
One of the methods to generate the H2 fuel for polymer electrolyte membrane fuel cell (PEMFC) is the steam reforming of methanol. Typically, reformed gas from methanol steam reforming has contained 0.5~1 vol% CO. The trace amount of CO must be reduced below 10 ppm because the Pt active site of Pt-based anode catalyst of PEMFC is easily poisoned by CO at low temperature. The effective way to reduce the 0.5~1vol% CO concentration is the preferential CO oxidation. In this study, for the application in small PEMFC to the portable devices, a micro-reactor for preferential CO oxidation (micro-PrOx) was fabricated on 500 um thick p-type (110) silicon wafer by micro electro mechanical system (MEMS) and silicon micromachining technology. Micro-PrOx had 17 parallel channels with 600 um width, 240 um depth, and varying in the channel lengths. Pt/Al2O3 catalyst (Johnson Matthey) was used in the experiments and the new method in catalyst coating (fill-and-dry coating) was introduced to coat the inner walls of micro-channels of pre-assembled micro-reactor. We investigated the effect of lambda (O2/CO ratio), feed rate, and channel shape on the performance of micro-PrOx at the various temperatures from 190 to 300℃. |
