Hydrogen production via a two-step water splitting thermochemical cycle based on metal oxide – A review

A Z-scheme of a linear conjugated polymer photocatalyst and a metal oxide is able to facilitate overall water splitting without non-scalable sacrificial reagents showing potential for sustainable hydrogen production.

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ChemInform Abstract: THE COPPER-CHLORINE THERMOCHEMICAL CYCLE OF WATER SPLITTING FOR HYDROGEN PRODUCTION

Chemischer Informationsdienst ◽

10.1002/chin.198446030 ◽

1984 ◽

Vol 15 (46) ◽

Author(s):

M. M. BARBOOTI ◽

R. R. AL-ANI

Keyword(s):

Hydrogen Production ◽

Water Splitting ◽

Thermochemical Cycle

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Reactive Pellets for Improved Solar Hydrogen Production Based on Sodium Manganese Ferrite Thermochemical Cycle

ASME 2008 2nd International Conference on Energy Sustainability, Volume 2 ◽

10.1115/es2008-54170 ◽

2008 ◽

Author(s):

Carlo Alvani ◽

Mariangela Bellusci ◽

Aurelio La Barbera ◽

Franco Padella ◽

Marzia Pentimalli ◽

...

Keyword(s):

High Temperature ◽

Hydrogen Production ◽

Water Splitting ◽

Sodium Carbonate ◽

Production Efficiency ◽

Manganese Carbonate ◽

Reactive System ◽

Thermochemical Cycle ◽

Manganese Ferrite ◽

Oxide Mixture

Hydrogen production by water-splitting thermochemical cycle based on manganese ferrite /sodium carbonate reactive system is reported. Two different preparation procedures for manganese ferrite/sodium carbonate mixture were adopted and compared in terms of materials capability to cyclical hydrogen production. According to the first procedure conventionally synthesized manganese ferrite, i. e. high temperature (1250 °C) heating in Ar of carbonate/oxide precursors, was mixed with sodium carbonate. The blend was tested inside a TPD reactor using a cyclical hydrogen production/material regeneration scheme. After few cycles the mixture resulted rapidly passivated and unable to further produce hydrogen. An innovative method that avoids the high temperature synthesis of manganese ferrite is presented. This procedure consists in a set of consecutive thermal treatments of a manganese carbonate/sodium carbonate/iron oxide mixture in different environments (inert, oxidative, reducing) at temperatures not exceeding 750 °C. Such material, whose observed chemical composition consists in manganese ferrite and sodium carbonate in stoichiometric amount, is able to evolve hydrogen during 25 consecutive water-splitting cycles, with a small decrease in cyclical production efficiency.

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Experimental Study for HIx Concentration by Electro-Electrodialysis (EED) Cells in the Water Splitting Sulfur-Iodine Thermochemical Cycle

ChemEngineering ◽

10.3390/chemengineering3020050 ◽

2019 ◽

Vol 3 (2) ◽

pp. 50 ◽

Cited By ~ 1

Author(s):

Giampaolo Caputo ◽

Irena Balog ◽

Alberto Giaconia ◽

Salvatore Sau ◽

Alfonso Pozio

Keyword(s):

Experimental Study ◽

Hydrogen Production ◽

Water Splitting ◽

Transport Number ◽

Hydriodic Acid ◽

Thermochemical Cycle ◽

Slow Increase ◽

Electro Osmosis ◽

A Current ◽

Splitting Process

The efficiency of HI concentration/separation from a HIx solution, (mixture of HI/H2O/I2) represents a crucial factor in the sulfur-iodine thermochemical water splitting process for hydrogen production. In this paper, an experimental study on HI cathodic concentration in HIx solution using stacked electro-electrodialysis (EED) cells was carried out under the conditions of 1 atm and at three different temperature (25, 55 and 85 °C) and using a current density of 0.10 A/cm2. Results showed that an increase in HI concentration can be obtained under certain conditions. The apparent transport number (t+) in all the experiments was very close to 1, and the electro-osmosis coefficient (β) changed in a range of 1.08–1.16. The tests showed a detectable, though slow, increase in both the anodic iodine and cathodic hydriodic acid concentrations.

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Reactive Pellets for Improved Solar Hydrogen Production Based on Sodium Manganese Ferrite Thermochemical Cycle

Journal of Solar Energy Engineering ◽

10.1115/1.3142723 ◽

2009 ◽

Vol 131 (3) ◽

Cited By ~ 10

Author(s):

Carlo Alvani ◽

Mariangela Bellusci ◽

Aurelio La Barbera ◽

Franco Padella ◽

Marzia Pentimalli ◽

...

Keyword(s):

High Temperature ◽

Hydrogen Production ◽

Water Splitting ◽

Sodium Carbonate ◽

Production Efficiency ◽

Manganese Carbonate ◽

Reactive System ◽

Thermochemical Cycle ◽

Manganese Ferrite ◽

Oxide Mixture

Hydrogen production by water-splitting thermochemical cycle based on manganese ferrite/sodium carbonate reactive system is reported. Two different preparation procedures for manganese ferrite/sodium carbonate mixture were adopted and compared in terms of material capability to cyclical hydrogen production. According to the first procedure, conventionally synthesized manganese ferrite, i.e., high temperature (1250°C) heating in Ar of carbonate/oxide precursors, was mixed with sodium carbonate. The blend was tested inside a temperature programed desorption reactor using a cyclical hydrogen production/material regeneration scheme. After a few cycles, the mixture resulted rapidly passivated and unable to further produce hydrogen. An innovative method that avoids the high temperature synthesis of manganese ferrite is presented. This procedure consists in a set of consecutive thermal treatments of a manganese carbonate/sodium carbonate/iron oxide mixture in different environments (inert, oxidative, and reducing) at temperatures not exceeding 750°C. Such material, whose observed chemical composition consists of manganese ferrite and sodium carbonate in stoichiometric amounts, is able to evolve hydrogen during 25 consecutive water-splitting cycles, with a small decrease in cyclical production efficiency.

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Simulation of a Solar Receiver-Reactor for Hydrogen Production

ASME 2009 3rd International Conference on Energy Sustainability, Volume 1 ◽

10.1115/es2009-90273 ◽

2009 ◽

Cited By ~ 2

Author(s):

Martina Neises ◽

Felix Goehring ◽

Martin Roeb ◽

Christian Sattler ◽

Robert Pitz-Paal

Keyword(s):

Hydrogen Production ◽

Solar Radiation ◽

Thermal Behavior ◽

Water Splitting ◽

Solar Furnace ◽

Small Scale ◽

Mathematical Tool ◽

Thermochemical Cycle ◽

Set Up ◽

Solar Receiver

The transient thermal behavior of two solar receiver-reactors for hydrogen production has been modeled using Modelica/Dymola. The simulated reactors are dedicated to carry out the same chemical reactions but represent two different development stages of the project HYDROSOL and two different orders of magnitude concerning reactor size and hydrogen production capacity. The process itself is a two step thermochemical cycle, which uses mixed iron-oxides as a redox-system. The iron-oxide is coated on a ceramic substrate, which is placed inside the receiver-reactor and serves on the one hand as an absorber for solar radiation and on the other hand as the reaction zone for the chemical reaction. The process consists of a water splitting step in which hydrogen is produced and a regeneration step during which the used redox-material is being reduced. The reactor is operated between these two reaction conditions in regular intervals with alternating temperature levels of about 800 °C for the water splitting step and 1200 °C for the regeneration step. Because of this highly dynamic process and because of fluctuating solar radiation during the day, a mathematical tool was necessary to model the transient behavior of the reactor for theoretical studies. Two models have been developed for two existing receiver-reactors. One model has been set up to simulate the behavior of a small scale test reactor, which has been built and tested at the solar furnace of DLR in Cologne. Results are very promising and show that the model is able to reflect the thermal behavior of the reactor. Another model has been developed for a 100 kWth pilot reactor which was set up at the Plataforma Solar de Almeri´a in Spain. This model is based on the first model but special geometrical features had to be adapted. With this model temperatures and hydrogen production rates could be predicted.

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