Minimization of hot spot in a microchannel reactor for steam reforming of methane with the stripe combustion catalyst layer

•A heat exchanger microchannel reactor for steam reforming of methane was studied.•A striped catalyst layer configuration was proposed for the catalytic combustion.•Hot spot formation near the inlet was repressed by the stripe catalyst layer.•The stripe configuration was optimized using the response surface methodology.•The effects of design parameters on hot spot minimization were investigated.

Hot spot formation is inevitable in a heat exchanger microchannel reactor used for steam reforming of methane because of the local imbalance between the generated and absorbed heat. A stripe configuration of the combustion catalyst layer was suggested to make the catalytic combustion rate uniform in order to minimize the hot spot near the inlet. The stripe configuration was optimized by response surface methodology with computational fluid dynamics. With the optimal catalyst layer, the hot spot was not observed near the inlet and the maximum temperature decreased by 130 K from that of the uniform catalyst layer without any conversion loss. The maximum relative particle diameters of the uniform and the optimal stripe catalyst layer were about 3.68 and 2.51, respectively, and the surface-averaged particle diameter of the optimal stripe catalyst layer was 7.64% less than that of the uniform stripe catalyst layer.