Development of a gas fine cleaning system for NH3-operated hydrogen filling stations based on palladium membrane separation modules

Ammonia is considered to be one of the most econo­mical energy carriers in terms of storage and trans­port when it comes to buil­ding the Germany-wide hydrogen infra­struc­ture. In order to fully exploit the poten­tial of NH3 at this point, however, consis­tent deve­lo­p­ment of dynamic conver­sion tech­no­lo­gies for statio­nary and mobile appli­ca­tions is required. In commer­ci­ally available NH3 crackers, a mixture of H2 and N2 is produced, which also contains traces of NH3 of up to one per thousand. However, such a propor­tion is still too high for hydrogen filling stations to supply fuel cell appli­ca­tions, and further measures are required to treat the hydrogen.
For this reason, the sub-project partner Zentrum für Brenn­stoff­zel­len­Technik (ZBT) is deve­lo­ping and cons­truc­ting an ultra-fine clea­ning system in the form of a membrane sepa­ra­tion module. The heart of the module is a palla­dium membrane a few micro­me­ters thick, which sepa­rates high-purity hydrogen from the gas mixture under the influence of tempe­ra­ture and pres­sure and thus makes it available for appli­ca­tions with high purity requi­re­ments. The basic archi­tec­ture of the new membrane sepa­ra­tion module is based directly on the struc­ture of fuel cells. It, ther­e­fore, allows the advan­tages of this tech­no­logy to be trans­ferred in terms of a flexible, modular design and stage-based upsca­ling in the form of stacking indi­vi­dual hydrogen sepa­ra­tion cells. Exentis Tooling GmbH uses an advanced indus­tria­lized 3D screen prin­ting process via Exentis Addi­tive Manu­fac­tu­ring tech­no­logy to produce the main repea­ting compo­nent of the module in the form of micros­truc­tured hydrogen sepa­rator plates. PSL Technik GmbH supports the deve­lo­p­ment work around the membrane sepa­ra­tion module with laser-supported methods for the realiza­tion of produc­tion-ready and process-critical sealing concepts.