Development of compact and efficient hydrogen production module with membrane on catalyst

A new module of Pd-based membrane on catalyst (MOC) for hydrogen production has been developed. The MOC is based on a unique concept of combining the Pd-based membrane and catalysts for steam methane reforming (SMR). A thinner Pd-based membrane is fabricated on a catalytic substrate, and thus it is possible to lower the module cost by reducing the amount of Pd and applying the well-established mass-production technology. Although the MOC module showed hydrogen production capability as high as the conventional hydrogen production membrane modules, the purity of the produced hydrogen decreased rapidly in several 10 h. The main reason of the decrease of the hydrogen purity in a short time is an increase of leakage of the reformed gas into the permeating hydrogen. To improve the durability of the MOC and maintain the purity of the produced hydrogen, we modified the MOC manufacturing process to prevent the leakage. As a result, the durability of the MOC is improved and the purity of the produced hydrogen has been over 99.99% for 1000 h. In addition to the experimental testing of the MOC, we carried out numerical calculations on the MOC performance, and a good agreement between the experimental and calculated results was obtained.