Processes of photocatalytically generating molecular hydrogen (H.sub.2) and systems for carrying out the processes. Liquid water is contacted with an amount of a ID and/or 2D carbon-doped nanofilament-based photocatalyst material composition and a hole scavenger chemical, optionally under an inert gas purge, at temperature of 100 C. or less, generating gaseous molecular hydrogen by irradiating the liquid water, the hole scavenger chemical, and the photocatalyst for about 1 to 300 hours with at least one sun illumination (UV-Vis light (250-650 nm)).

This inorganic compound includes M, O, and F, in which M is one or more kinds of transition metal elements, when defining a molar ratio of O as b and defining a molar ratio of F as cc, (b/c) is 0.60 or more and 2.30 or less, and a half-value width of a diffraction peak of a (110) plane obtained by X-ray diffraction analysis is 0.60 or less. Also, the inorganic compound includes M, O, and F, in which M is one or more kinds of transition metal elements, when defining a molar ratio of O as b and defining a molar ratio of F as c, (b/c) is 1.50 or less, and a half-value width of a diffraction peak of a (110) plane obtained by X-ray diffraction analysis is 0.45 or more.

There is a high-temperature tube bundle reactor built from material derived from metal oxides such as alumina-zirconia. The heat exchange surfaces of the reactor have a specific surface finish, and the bulk matrix of the material of the various components of the reactor has a specific grain, pore size and porosity characteristics. There is also a high-temperature redox process using the reactor.

A method for photothermal synthesis gas production. The method comprises feeding methane and carbon dioxide into a photothermal reactor, the photothermal reactor comprising a catalyst. The catalyst comprises a metal organic framework (MOF) derived nanocomposite oxide catalyst, the MOF derived nanocomposite oxide catalyst being grown on titanium dioxide (TiO.sub.2) quantum dots.

In an apparatus producing hydrogen gas by a decomposition reaction of water using a photocatalyst, the water is warmed with waste heat of a light source for improving the production efficiency of hydrogen gas. The hydrogen gas producing apparatus 1 comprises a container portion receiving water; a photocatalyst body, dispersed or placed in the water, having a photocatalyst material to generate excited electrons and electron holes by irradiation of light, causing the decomposition reaction of water which decomposes water into hydrogen and oxygen to generate hydrogen gas; a light source emitting the light to be irradiated to the photocatalyst body; and a housing carrying the light source; wherein the housing is placed in the water, which is warmed by the waste heat of the light source discharged from the housing surface which is coated with a photocatalyst material.

A plant and process for producing a hydrogen rich gas are provided, said process including the steps of: steam reforming a hydrocarbon feed into a synthesis gas; shifting the synthesis gas and conducting the shifted gas to a hydrogen purification unit, subjecting CO.sub.2-rich off-gas from the hydrogen purification unit to a carbon dioxide removal in a low temperature CO.sub.2-removal section and recycling CO.sub.2-depleted off-gas rich in hydrogen to the process. A drying unit upstream the CO.sub.2-removal section is provided, under the addition of regeneration gas produced in the plant and process.

A method of producing H.sub.2 may include passing a hydrocarbon feed into a reactor, wherein the hydrocarbon feed comprises at least 50 mol. % methane. The method may also include contacting the methane with a catalyst in the reactor to form a product comprising H.sub.2. The catalyst may comprise a support and one or more catalytically-active metals. At least 99 wt. % of the one or more catalytically-active metals may be present in the catalyst as single-atoms, based on a total weight of the one or more catalytically-active metals in the catalyst.

Compositions and methods for the catalysis of methane pyrolysis. Compositions include a catalyst that includes a medium entropy alloy particle. Methods include catalyzing the pyrolysis of methane using the catalyst.

Compositions and methods for the catalysis of methane pyrolysis. Compositions include a catalyst system that includes a medium entropy alloy particle and a support. Methods include catalyzing the pyrolysis of methane using the catalyst system.

A system for producing hydrogen gas includes a first container, a microwave emitter configured to direct a microwave to the first container, a steam condenser, a second container and an effluent conduit. The first container includes a first container body configured to hold a quantity of water and aluminum particles inside. The steam condenser connects the first container with a first end of the effluent conduit. A second end of the effluent conduit can be inserted in the second container. The microwave emitter can be operated to direct a microwave to the water and aluminum particles (when the water aluminum particles are present inside of the first container). The radiation of the water and aluminum particles with the microwave will cause hydrogen gas to dissociate from the water. The hydrogen gas will travel through the steam condenser and the effluent conduit to be stored in the second container.