Steam Reforming of Methanol and Ethanol in a Pd-Alloy Composite Membrane Reactor

H₂-selective Pd and Pd-alloy membranes in membrane reactor offer a unique opportunity for simultaneous production and separation of hydrogen from many of the industrially important steam reforming reactions by equilibrium shift. In this study, we investigated the steam reforming of methanol and ethanol in a Pd-alloy (Pd-Cu and Pd-Ag) composite membrane reactor. Defect free Pd-alloy thin-film membranes on microporous stainless steel (MPSS) support were fabricated in our laboratory using a newly developed surfactant induced electroless plating (SIEP). The Pd-alloy membranes were tested for thermal stability and H₂-perm-selectivity at 450 οC. Reforming reactions were studied using: (a) commercially available Ni-based steam reforming catalyst and (b) our in-house synthesized trimetallic Pd-Ni-Sn nano-catalyst supported on mesoporous silica. The effect of steam to alcohol ratio, temperature and space velocity on alcohol conversion, hydrogen yield and carbon monoxide suppression were examined for the two reforming reactions in the membrane reactor. We also investigated the reforming reactions in a packed-bed reactor (non-membrane reactor) under similar operating conditions. In this presentation, we will present some of these experimental results.