Methods and devices and aspects thereof for generating power using PEM fuel cell power systems comprising a rotary bed (or rotatable) reactor for hydrogen generation are disclosed. Hydrogen is generated by the hydrolysis of fuels such as lithium aluminum hydride and mixtures thereof. Water required for hydrolysis may be captured from the fuel cell exhaust. Water is preferably fed to the reactor in the form of a mist generated by an atomizer. An exemplary 750 We-h, 400 We PEM fuel cell power system may be characterized by a specific energy of about 550 We-h/kg and a specific power of about 290 We/kg. Turbidity fixtures within the reactor increase turbidity of fuel pellets within the reactor and improve the energy density of the system.

A catalytic device includes a hollow body, a piston housed in the hollow body, a catalyst of a gas generation reaction based on bringing a reactive liquid into contact with the catalyst, the catalyst being housed in a catalysis chamber, the piston and the hollow body defining a hermetic compression chamber for containing a compressible fluid, and being mobile relative to one another between a closed position in which the catalysis chamber is tight to the reactive liquid, and an open position for the entry of the reactive liquid into the catalysis chamber. The catalytic device is conformed to switch from the open position to the closed position, respectively from the closed position to the open position, when the compressible fluid is contained in the compression chamber and a force applied to the piston is greater than or equal to, respectively less than, a closure force.

Methods and systems are provided for treating the tail gas stream of a sulfur recovery plant. The methods including generating a tail gas stream from a sulfur recovery plant, treating the tail gas stream with a hydrogen sulfide removal unit and a hydrogen selective membrane unit, generating a stream low in hydrogen sulfide and a stream rich in hydrogen. The hydrogen sulfide rich stream is recycled to the sulfur recovery unit. The hydrogen selective membrane unit includes a glassy polymer membrane selective for hydrogen over hydrogen sulfide and carbon dioxide.

Methods and systems are provided for treating the tail gas stream of a sulfur recovery plant. The methods including generating a tail gas stream from a sulfur recovery plant, treating the tail gas stream with a hydrogen sulfide removal unit and a hydrogen selective membrane unit, generating a stream low in hydrogen sulfide and a stream rich in hydrogen. The hydrogen sulfide rich stream is recycled to the sulfur recovery unit. The hydrogen selective membrane unit includes a glassy polymer membrane selective for hydrogen over hydrogen sulfide and carbon dioxide.

A method of producing hydrogen and sequestering carbon or sulfur includes generating a fluid including at least one of water, steam, hydrogen sulfide, carbon dioxide and heat as a byproduct of a surface facility and injecting the fluid into a subsurface formation. The subsurface formation can include a porous rock, in various forms of porosity such as intragranular, intergranular, fracture porosity. The method can further include heating the fluid to stimulate an exothermic reaction of the fluid with components of the subsurface rock formation and produce a hydrogen reaction product and one or more of sulfur minerals from the hydrogen sulfide or carbon minerals from the carbon dioxide. The fluid can be heated to between about 25° C. and about 500° C. The method can also include extracting the hydrogen produced from the reaction of the fluid with the subsurface rock formation and mineralizing at least one of the sulfur or carbon in the porous rock.

A method of producing hydrogen and sequestering carbon or sulfur includes generating a fluid including at least one of water, steam, hydrogen sulfide, carbon dioxide and heat as a byproduct of a surface facility and injecting the fluid into a subsurface formation. The subsurface formation can include a porous rock, in various forms of porosity such as intragranular, intergranular, fracture porosity. The method can further include heating the fluid to stimulate an exothermic reaction of the fluid with components of the subsurface rock formation and produce a hydrogen reaction product and one or more of sulfur minerals from the hydrogen sulfide or carbon minerals from the carbon dioxide. The fluid can be heated to between about 25° C. and about 500° C. The method can also include extracting the hydrogen produced from the reaction of the fluid with the subsurface rock formation and mineralizing at least one of the sulfur or carbon in the porous rock.

The present invention relates to the reduction of materials at low temperatures (<600° C.) by means of microwave radiation without needing to use chemical reducing agents or electrical contacts. It relates more specifically to a method for reducing a material, which comprises the following steps: applying microwave radiation to a material disposed in a microwave application cavity; and separating simultaneously the fluid oxidation products generated from the reduced material,
such that the method is carried out without chemical reducing agents or electrical contacts.

A power generator and method include passing ambient air via an ambient air path past a cathode side of the fuel cell to a water exchanger, picking up water from the cathode side of the fuel cell and exhausting air and nitrogen to ambient, passing hydrogen via a recirculating hydrogen path past an anode side the fuel cell to the water exchanger, where the water exchanger transfers water from the ambient air path comprising a cathode stream to the recirculating hydrogen path comprising an anode stream, and passing the water to a hydrogen generator to add hydrogen to the recirculating hydrogen path and passing the hydrogen via the recirculating hydrogen path past the anode side of the fuel cell.

A hydrogen system includes: a compressor that applies a voltage between an anode and a cathode to move hydrogen in hydrogen-containing gas supplied to the anode to the cathode via an electrolyte membrane and compress the hydrogen; a first flow path through which hydrogen-containing gas discharged from the anode of the compressor flows; a second flow path to supply cathode off-gas to the anode of the compressor, the cathode off-gas being discharged from the cathode of the compressor; an on-off valve provided on the second flow path; and a controller that opens the on-off valve in a normal stop.

A hydrogen system includes: a compressor that applies a voltage between an anode and a cathode to move hydrogen in hydrogen-containing gas supplied to the anode to the cathode via an electrolyte membrane and compress the hydrogen; a first flow path through which hydrogen-containing gas discharged from the anode of the compressor flows; a second flow path to supply cathode off-gas to the anode of the compressor, the cathode off-gas being discharged from the cathode of the compressor; an on-off valve provided on the second flow path; and a controller that opens the on-off valve in a normal stop.