Patent ID: 8591850

Claim:
A method of removing carbon monoxide from a mixture gas obtained by reforming a raw fuel, the mixture gas containing hydrogen and carbon monoxide to produce a fuel gas to be supplied to a polymer electrolyte fuel cell, the method consisting of the following steps: flowing a reactant gas comprising the mixture gas and an oxidizer through a pipe into an inlet of a single carbon monoxide removal reactor, said reactor having in its casing a catalyst layer comprising a carbon monoxide removal catalyst consisting of an alumina support and a member selected from the group consisting of ruthenium, rhodium, and palladium supported on said support, the carbon monoxide removal catalyst layer having a temperature adjusted to 80° C. to 180° C.; said flowing step including cooling the mixture gas or reactant gas by flowing the mixture gas or reactant gas through a heat exchanger provided in the pipe, and condensing steam of the mixture gas or reactant gas; said flowing step further including reducing the dew point of the reactant gas to 60° C. or less under the processing pressure by separating water of the reactant gas through a drain trap provided in the pipe, the temperature of the reactant gas having been reduced by cooling through the heat exchanger; introducing the resultant reactant gas into the carbon monoxide removal reactor; and removing the carbon monoxide by reacting the oxidizer and the mixture gas on the carbon monoxide removal catalyst, and restricting wetting of said carbon monoxide removal catalyst.