An underwater hydrogen generator can include a watertight reaction housing enclosing a metering chamber. The metering chamber can have an upper portion that terminates at a piston opening, and a lower portion that merges into a funnel, which can further terminate at a metering opening. The metering chamber can be filled with an acid accelerator, and the watertight reaction void can be partially filled with NaBH.sub.4 in solution. The generator can further include a seawater float valve that can be in fluid communication between the external environment, the metering chamber and the void defined by the reaction housing. The float valve, metering chamber and reaction housing can cooperate to generate hydrogen when said generator is submerged, by allowing seawater to contact both the acid accelerator and the NaBH.sub.4. The size of the metering opening can determine the rate at which acid accelerator is added to the NaBH.sub.4 solution.

A method for the production of hydrocarbon(s), such as methane, substituted hydrocarbons, such as methanol, or the production of hydrogen, the method comprising the steps of contacting a first catalyst with water in order to photocatalyse the splitting of at least some of the water into hydrogen and oxygen; and contacting a second catalyst with a gas stream comprising carbon dioxide and at least some of the hydrogen produced from step (a) in order to photocatalyse the reaction between the hydrogen and carbon dioxide to produce hydrocarbon(s), such as methane, and/or substituted hydrocarbons, such as methanol. In an embodiment, the catalyst comprises gold and or ruthenium nanoclusters supported on a substrate.

A member for hydrogen production includes a ceramic composite in which a plurality of ceramic particles having an average particle diameter ranging from 5 nm to 200 nm are dispersed in a porous insulator having a different component from the ceramic particles. The ceramic particles comprise at least one substance selected from the group consisting of AXO.sub.3 (where 01, A: at least one of rare earth elements, alkaline earth elements, and alkali metal elements, X: at least one of transition metal elements and metalloid elements, and O: oxygen), cerium oxide, and zirconium oxide as a main component.

An underwater hydrogen generator can include a watertight reaction housing enclosing a metering chamber. The metering chamber can have an upper portion that terminates at a piston opening, and a lower portion that merges into a funnel, which can further terminate at a metering opening. The metering chamber can be filled with an acid accelerator, and the watertight reaction void can be partially filled with NaBH.sub.4 in solution. The generator can further include a seawater float valve that can be in fluid communication between the external environment, the metering chamber and the void defined by the reaction housing. The float valve, metering chamber and reaction housing can cooperate to generate hydrogen when said generator is submerged, by allowing seawater to contact both the acid accelerator and the NaBH.sub.4. The size of the metering opening can determine the rate at which acid accelerator is added to the NaBH.sub.4 solution.

The present invention provides a system and method for producing high-purity vanadium pentoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to fluidized gas phase hydrolyzation and fluidized calcination, thereby producing a high-purity vanadium pentoxide product and a by-product of hydrochloric acid solution. The system and method have advantages of favorable adaptability to raw material, no discharge of contaminated wastewater, low energy consumption in production, low operation cost, stable product quality, etc.

Systems and methods for sequestering carbon, evolving hydrogen gas, producing iron oxide as magnetite, and producing magnesium carbonate as magnesite through sequential carbonation and serpentinization/hydration reactions involving processed olivineand/or pyroxene-rich ores, as typically found in mafic and ultramafic igneous rock. Precious or scarce metals, such nickel, cobalt, chromium, rare earth elements, and others, may be concentrated in the remaining ore to facilitate their recovery from any gangue material.

An underwater hydrogen generator can include a watertight reaction housing enclosing a metering chamber. The metering chamber can have an upper portion that terminates at a piston opening, and a lower portion that merges into a funnel, which can further terminate at a metering opening. The metering chamber can be filled with an acid accelerator, and the watertight reaction void can be partially filled with NaBH.sub.4 in solution. The generator can further include a seawater float valve that can be in fluid communication between the external environment, the metering chamber and the void defined by the reaction housing. The float valve, metering chamber and reaction housing can cooperate to generate hydrogen when said generator is submerged, by allowing seawater to contact both the acid accelerator and the NaBH.sub.4. The size of the metering opening can determine the rate at which acid accelerator is added to the NaBH.sub.4 solution.

A chemical-looping system utilizes oxygen-carrier particles to produce syngas from carbonaceous fuels. The system provides a circuitous flow path for the oxygen-carrier particles, which are used to partially oxidize the fuel to produce syngas. The circuitous flow path can proceed through a plurality of unit operations, including a reducer, a conversion reactor, an oxidizer, and a combustor. The conversion reactor is designed to partially oxidize carbonaceous fuel in co-current flow with the oxygen-carrier particles to produce syngas. In embodiments including an oxidizer, the oxidizer is designed to at partially re-oxidize the carrier particles, yielding hydrogen that can be mixed with partially oxidized products from the conversion reactor to adjust syngas quality. The combustor can be used to fully oxidize the carrier particles traveling in a closed loop. Reactions carried out in the combustor are highly exothermic and yield thermal energy that is absorbed by the carrier particles. The absorbed energy is used at other parts of the process, including the conversion reactor, to drive endothermic reactions. In this manner the system can be operated autothermally or nearly so. Methods of producing syngas are also disclosed.

Metal oxides having a lower activation temperature and enhanced oxygen mobility are disclosed. The metal oxides comprise oxygen (O), cerium (Ce) and one or both of iron (Fe) and uranium (U). Also disclosed are methods for producing hydrogen or carbon monoxide from water or carbon dioxide using the metal oxides.

The present invention relates to an installation for the production of dihydrogen comprising: a reaction enclosure (1) intended to contain an oxidizable material, an alkaline solution feed system (2) fluidly connected to the reaction enclosure (1), a pure water (31) supply system (3) fluidly connected to the reaction enclosure (1), a dihydrogen collection system (4) downstream of the reaction enclosure (1), the collection system (4) being fluidly connected: to the reaction enclosure (1), to the supply system (3), and to a storage receptacle (5) configured to store the produced dihydrogen at a desired high pressure.