Investigation on high hydrogen production from methanol reforming in a microreactor with stacked reforming channels

Methanol steam reforming (MSR) for hydrogen production in compact reformers has been widely explored owing to advantages of safe hydrogen storage, mild operating conditions, and suitability for on-site hydrogen generation. To enhance the hydrogen production performance of methanol steam reforming, a U-shaped reactor with stacked reforming channels is proposed. Effects of reaction temperature (T), methanol flow rate (v), water-to- methanol ratio (Rm) and flow direction on the performance of Parallel-3U and Parallel-4U reactors are investigated. The results show that the performance of parallel-4U reactor is better than that of parallel-3U reactor, and the methanol conversion rate (n) is as high as 99 % at high temperature. Also, the reaction temperature increases n by improving the catalyst activity and promoting the endothermic reaction rates of SR and DE. The flow rate affects n and the carbon dioxide selectivity (SCO2) by changing the residence time of reactants in the reforming channel. Meanwhile, heat can be well transferred to the reforming chamber by changing the flow direction between the combustion and the reforming chamber. Correspondingly, the excess vapor can increase the methanol conversion and promote the methanol reforming reaction at high R m . In the parallel-4U reactor, the optimum hydrogen production is achieved at R m = 1.6, v = 0.2 mL/min and T = 260 degrees C. The orthogonal analysis reveals the key effects of these parameters on n and S CO2 , highlighting the importance of optimizing reactor conditions for efficient hydrogen production.