Novel copper foam with ordered hole arrays as catalyst support for methanol steam reforming microreactor

Abstract

Methanol steam reforming microreactor is regarded as one of the effective approaches for online hydrogen source for fuel cells and the catalyst support is one of the most important component of microreactors. However, there is great room to improve the performance of microreactor by optimizing the structure of catalyst support. In this study, copper foams with different types of hole arrays were used as catalyst supports for constructing a new type of cylindrical laminated methanol steam reforming microreactor for hydrogen production. A laser processing method was used to fabricate the copper foams with hole arrays and a two-layer impregnation method was used to load the Cu/Zn/Al/Zr catalysts. The sphere-cut tetrakaidecahedrons model of copper foam was established and macroscopic numerical analysis were used to analyze the reactants distribution in copper foams. The optimal distribution of hole arrays of the copper foam was obtained by investigating the reaction characteristics under different flow rates of the reactant, reaction temperatures, and loading amounts of catalyst. The experimental results show that the microreactor for hydrogen production using copper foam with ordered hole arrays shows the higher methanol conversion and hydrogen flow rate comparing the ones without hole array. Because of improvement of the radial distribution uniformity and increase of the axial flow rates of the reactants, the best reaction performance of microreactor for hydrogen production is obtained when the copper foam with the configuration in which the hole size decreases along the radial and axial direction.