A fuel cell system comprises a fuel cell stack and a carbon monoxide clean-up system in communication with the fuel cell stack. The carbon monoxide cleanup system comprises a first water gas shift reactor, a first hydride heat exchanger, and a second water gas shift reactor. The first water gas shift reactor comprises a first water gas shift catalyst. The first hydride heat exchanger comprises a first metal hydride, and is in communication with the first water gas shift reactor. The second water gas shift reactor comprises a second water gas shift catalyst, and is in communication with the first heat exchanger. The first hydride heat exchanger, and the second water gas shift reactors are disposed such that a reactant stream may pass through the first water gas shift reactor prior to passing through the first heat exchanger, and then pass through the second water gas shift reactor.