Different catalytic systems and rea

Different catalytic systems and reactor designs have been proposed for the CO-PROX reaction. In a recent study Bion et al. [10] review the performances of noble metals (including Pt, Ru, Rh, Pd and Au) and transition metal oxides catalysts and compare theadvantages and drawbacks for each type of catalysts in terms of activity and selectivity including the influence of the presence of CO2 and H2O in the reactants flow. They conclude that CuO–CeO2 catalysts are very attractive for industrial applications since their excellent performances, stability and low cost compared to noble metal-based catalysts. Dudfield et al. [11,12] operated a compact fin heat-exchangerreactor containing 2.5% Pt–Ru catalyst in the CO-PROX reaction.Using a two-stage configuration this unit allowed reductions inthe CO concentrations down to 15 ppm. Silicon wafers [13] oraustenitic stainless steel plates [14,15] were used for buildingmicrochannel reactors for the PROX reaction. Hwang et al. [16]studied the reaction over a silicon-based microreactor coated witha Pt/Al2O3 catalyst, yielding 99.4% CO conversion. Kim et al.