Palladium based membrane reactors for hydrogen production

The application of membrane reactors has been widely studied for methane steam reforming and water gas shift using Pd-alloy membranes. The integration of reaction and separation allows obtaining higher conversion degrees, smaller reactor volumes and higher efficiencies compared with conventional systems. In the last decade, much thinner dense Pd-based membranes have been produced that can be used in membrane reactors. However, the thinner the membranes the higher the flux and the higher the effect of concentration polarization in packed beds. A reactor concept that can circumvent (or at least strongly reduce) concentration polarization is the fluidized bed membrane reactor configuration, and also can improve the heat transfer. Tecnalia and TU/e are involved in four European projects that are related to development of fluidized bed membrane reactors for hydrogen production using thin Pd-Ag (<5 µm) supported membranes for different application: In DEMCAMER project a water gas shift membrane reactor was developed for high purity hydrogen production. REFORCELL aims at developing a high efficient heat and power micro-cogeneration system (m-CHP) using a methane reforming fluidized membrane reactor. The main objective of FERRET is the development of a flexible natural gas membrane reformer directly linked to the fuel processor of the micro-CHP system. FLUIDCELL aims the Proof-of-Concept of a m-CHP system for decentralized off-grid using a bioethanol reforming membrane reactor. The fluidized bed system allows operating at a virtually uniform temperature which is beneficial in terms of both membrane stability and durability and for the reaction selectivity and yield. The main results obtained in these projects in terms of performance of the membranes and the membrane reactors will presented in this work.