CO Preferential Oxidation (CO-PrOx) is particularly appealing when applied to low -scale/portable reformer-PEMFC systems due to its fairly simple implementation, low operation costs and minimal loss of hydrogen [2]. Also, microreaction technology provides enhanced safe operation in the management of hydrogen-rich streams because large volumes are avoided, allowing the use of process parameters of otherwise explosive regimes. However, the natural trend in miniaturization of fuel cell systems is followed with increasing difficulty by actual microreforming/micro-cleaning units.