In the thermochemical water splitting process by CuCl cycle, oxygen gas is produced by a thermolysis process in a three-phase reactor. IN accordance with the teachings herein, a technique is provided to achieve the high challenging thermal requirements of the thermolysis reactor, whereby an optimized heat transfer configuration is used. The technique involves using some of the pre-heated stoichiometric oxygen gas produced from the thermolysis reaction, to transfer heat directly to the slurry of molten CuCl and solid Cu.sub.2OCl.sub.2 inside the thermolysis reactor. Experiments were performed to examine the volumetric heat transfer coefficient for the direct contact heat transfer between the gas and the slurry. It was found that the thermal scale up analysis of the thermolysis reactor with direct contact heat transfer, is based on the amount of heat carried by the oxygen gas rather than the amount of heat transferred by direct contact heat transfer.

The invention relates to a plant and a method for the production of decarbonised hydrogen using carbonate, water, gas containing hydrocarbons and electricity. The plant 100 first of all comprises an electric calciner 10, a contactor 20, an apparatus for correcting the pH 30 and a metering device 40. The plant 100 is suitable for receiving electrical energy, carbonate, water, natural gas at its input and for releasing decarbonised hydrogen at its outlet and an alkaline water rich in bicarbonates which, once released into the sea, represents the permanent storage for CO.sub.2. The plant 100 uses bicarbonates as permanent storage of CO.sub.2 in the sea: this storage allows the production of decarbonised hydrogen at low costs and in modular plants.

A system for producing hydrogen from water by a thermochemical cycle, for example the sulphuriodine cycle, comprises a reactor having reaction zones for implementing the reactions of the cycle. The reaction zones are interconnected by a fluid circuit and the reactor is configured to direct reaction product(s) from any reaction zone to another reaction zone to provide reactant(s) for the other reaction zone. Fluid is recirculated around the fluid circuit so that reaction product(s) from downstream reaction zone(s) are reused as reactant(s) for upstream reaction zone(s). Heat generated in reaction zone(s) is also reused in other reaction zone(s). The resulting system is energy efficient as well as being efficient in its use of reactants.

The present disclosure relates to a processes and systems for producing fuels from biomass with high carbon conversion efficiency. The processes and systems described herein provide a highly efficient process for producing hydrocarbons from biomass with very low Green House Gas (GHG) emissions using a specific combination of components, process flows, and recycle streams. The processes and systems described herein provide a carbon conversion efficiency greater than 95% with little to no GHG in the flue gas due to the novel arrangement of components and utilizes renewable energy to provide energy to some components. The system reuses water and carbon dioxide produced in the process flows and recycles naphtha and tail gas streams to other units in the system for additional conversion to syngas to produce hydrocarbon-based fuels.

In the thermochemical water splitting process by the CuCl cycle, oxygen gas is produced by a thermolysis process in a three-phase reactor. A precise knowledge of the hydrodynamic and heat transfer analyses is required for the scale-up of the thermolysis reactor. However, in the experimental studies of the scale up analysis, there are some challenges in using the actual materials of the thermolysis reactor products (i.e. molten salt CuCl and oxygen gas). In accordance with the teachings herein, alternative materials are defined, by using dimensional analyses, to simulate the hydrodynamic and heat transfer behaviors of the actual materials. It has been found that these alternative materials are liquid water at 222 C. and helium gas at 902 C. The alternative materials provide safe environment for the experimental runs as well as lower operating temperature. Furthermore, these alternative materials are more readily available and are low cost.

In the thermochemical water splitting process by CuCl cycle, oxygen gas is produced by a thermolysis process in a three-phase reactor. IN accordance with the teachings herein, a technique is provided to achieve the high challenging thermal requirements of the thermolysis reactor, whereby an optimized heat transfer configuration is used. The technique involves using some of the pre-heated stoichiometric oxygen gas produced from the thermolysis reaction, to transfer heat directly to the slurry of molten CuCl and solid Cu.sub.2OCl.sub.2 inside the thermolysis reactor. Experiments were performed to examine the volumetric heat transfer coefficient for the direct contact heat transfer between the gas and the slurry. It was found that the thermal scale up analysis of the thermolysis reactor with direct contact heat transfer, is based on the amount of heat carried by the oxygen gas rather than the amount of heat transferred by direct contact heat transfer.

The present disclosure relates to methods for producing hydrogen and calcium- or magnesium-bearing carbonates by capturing, converting, and storing carbon dioxide. The methods may include providing one or more calcium- or magnesium-bearing compounds; providing one or more water-soluble oxygenates; providing a plurality of catalysts; and reacting one or more calcium- or magnesium-bearing compounds and one or more water-soluble oxygenates with plurality of catalysts under conditions to produce hydrogen and calcium- or magnesium-bearing carbonates. The methods may include providing one or more calcium- or magnesium-bearing silicates; providing carbon monoxide; providing water vapor; and reacting one or more calcium- or magnesium-bearing silicates, carbon monoxide, and water vapor. The methods may include providing one or more calcium- or magnesium-bearing compounds; providing one or more water-soluble oxygenates; providing a catalyst; and reacting one or more calcium- or magnesium-bearing compounds and one or more water-soluble oxygenates with said catalyst.

A hydrogen release and storage system (100) of the present invention includes a hydrogen compound member (101), a container (102) that accommodates the hydrogen compound member (101), a heating apparatus (103) configured to heat the inside of the container (102), a cooling apparatus (104) configured to cool the inside of the container (102) and a water supply apparatus (105) configured to supply water to the container (102).