Micro-channel reactors are characterized by high heat and masstransfer rates and therefore show large promise in the development of miniature fuel processors for small scale electricity production. For portable power generation, micro-reactors may outperform conventional reactor designs, leading to lower reactor volumes and weights . Several advantages of applying micro-reactors in comparison with conventional fixed-bed technology for the highlyexothermic CO PrOx reaction were demonstrated in different studies. A high rate of heat removal from the thin catalytic film deposited onto the micro-channel walls allows for near-isothermaloperation and in this way prevents the onset of side reactions (viz., hydrogen oxidation or reverse WGS) and extends the operational window [8–10]