Description:

Power+Energy, a leading supplier of commercial Hydrogen Membrane products, introduces a line of Micro-Channel Palladium-alloy Membrane assemblies which have been specifically engineered to optimize the extraction of hydrogen from reformate streams. In addition to the separation of hydrogen from a reformate stream, the Micro-Channel Palladium-alloy Membranes also function as a Membrane Reactor, and can drive reactions beyond traditional equilibrium levels if operated at appropriate process conditions. For example, the membranes can further drive water-gas shift reactions for reformates. This membrane configuration may be operated to maximize hydrogen recovery to extremely high levels (>95%). The configuration may be used as a durable membrane reactor.

Power+Energy offers these membranes in a variety of capacities and with several membrane alloys, enabling the maximization of recovery, even in the presence of sulfur impurities.

Principle of Operation:

The Micro-Channel Membrane Separator/Reactor consists of a 316L stainless steel cell, incorporating tubular palladium-alloy membranes that act as both the catalyst and diffusion element. In order to effectively utilize palladium-alloy membranes, the hydrogen must be brought into contact with the inner surfaces of the palladium-alloy tube. The membrane acts as a selective barrier, passing only atomic through the tube wall while excluding all other gases.

Molecular hydrogen is adsorbed onto the surface, where it dissociates into atomic hydrogen. This atomic hydrogen diffuses through the lattice as determined by the pressure gradient. The hydrogen atoms recombine on the low-pressure side of the membrane into molecular hydrogen, with only 1 ppb total impurities.

Additionally, because the palladium alloy acts as a catalyst, it can drive chemical reactions, such as the water-gas shift reaction, without the need for additional catalysts. Because hydrogen is removed immediately upon generation, the equilibrium point is continuously shifted. The result is a much higher ultra-pure hydrogen yield than is possible under ordinary equilibrium rates and conditions.

Applications:

Power+Energy Micro-Channel Membrane Separators and Reactors can be used to extract hydrogen from any reformed fuel. This provides an effective means to deliver high-quality hydrogen for PEM fuel cells and other hydrogen-fueled energy solutions.

Candidate fuels include:

• Alcohols, such as methanol and ethanol
• Diesel, gasoline, propane, and natural gas
• Ammonia
• Syngas
• Bio-fuels
• Landfill gases

Process Specifications:

Reformate feed gas inlet pressure      100–350 PSIG

Operating temperatures                       300–750°C

Mechanical Specifications:

Tubing/cell material                                316L stainless steel

Outlet connections                                316L stainless steel tubing

Finish on all UPH tubing                         Electro-polished

Finish on all UPH cell surfaces              Micro-polished

Available Capacities:

Micro-Channel Hydrogen Separators and Membrane Reactors are available in a wide variety of capacities. The photograph at the top of the page shows three examples.

Standard sizes* include 100W, 500W, 1kW, 5kW, and 10kW.

*Nominal capacities based on methanol reformate, with an inlet pressure of 150 PSIG and hydrogen outlet pressure of 5 PSIG.