HYSYDAYS
1st World Congress of Young Scientists on Hydrogen Energy Systems

ISBN Print: 1-56700-230-7

WATER GAS SHIFT CATALYSTS FOR CO CLEAN UP FOR FUEL CELL ON MOBILE APPLICATIONS

DOI: 10.1615/HYSYDAYS2005.120
pages 81-85

Abstrakt

Efforts have been aimed at utilizing the water–gas shift reaction (WGSR) (CO+H2 O= CO2+H2) (ΔH0 298K = −41,2 kJ/mol) for primary CO cleanup and additional hydrogen generation of hydrocarbon reformate gas, followed by a preferential oxidation step to reduce the CO level to about 10 ppm to feed a PEM fuel cell. For the LTWGS, Au, Cu, Pt and Rh were deposited on CeO2 by means of two different deposition methods, that is incipient wetness impregnation (IWI) and combustion synthesis (CS), and the active element load was 2%.
According to the experimental results, the best catalyst powder for the LTWGS was 2% Pt−CeO2, which gives a CO residual concentration of 1.3% at 325°C, though the conversion temperature was rather high (T suggested for LTWGS is 180−250°C).
A preliminary catalytic activity test on a microchannelled reactor was also carried out. In order to determine the best operating conditions, tests were carried out with the same gas feed composition and at different space velocities, varying from 0.8 Nl/min/g to 2.4 Nl/min/g. The conversion increased at lower space velocity, in particular the equilibrium curve was approximatively reached at 0.8 and 1.2 Nl/min/g, and the residual CO concentrations were respectively 1.2% and 1.3%.
For HTWGS, the catalyst 2% Pt−CeO2 (IWI) was tested in powder.