Development of multilevel amplified methanol steam reforming microreactor with high hydrogen production rate

Abstract

Methanol steam reforming using microreactors has been regarded as a promising approach for in-situ hydrogen production, while the generally low hydrogen production rate limits its real application. This study proposed a multilevel series scaled-up methanol steam reforming microreactor with the aim to improve the hydrogen production rate, five methanol combustion chambers are parallel arranged and interspersed into the steam reforming chambers to improve the temperature heating rate and temperature distribution uniformity. A numerical model of methanol steam reforming chamber was established to investigate the flow velocity distribution inside the chamber. The flow velocity in the copper foam region are uniformly distributed, the variations of average flow velocity in cross sections of the copper foams are below 20 %. Experimental results showed that the temperature differences between different layers was lower than 6.7 °C and the variation is smaller than 7.3 °C. A stepwise methanol solution feeding rate test was performed and found the developed microreactor has a quite rapid response speed, the maximum reformate flowrate of 20683 ml/min can be achieved with methanol conversion of 88.3 %. The developed microreactor can significantly improve the hydrogen production rate and temperature distribution uniformity, indicating a potential application in high hydrogen consumption equipment.