Sulfur hydrogen production process

Westinghouse Electric Corporation (1980), A Study on the Electrolysis of Sulfur Dioxide and Water for the Sulfur Cycle Hydrogen Production Process, AESD-TME-3043, July. 

Sakurai, M., et al. (2000), Experimental Study on Side-reaction Occurrence Condition in the Iodine-sulfur Thermochemical Hydrogen Production Process , International Journal of Hydrogen Energy, 23, 613-619. 

This paper will discuss the development status of the Sulfur Cycle Hydrogen Production Process, the results of evaluations of process performance, and the program steps which can lead to commercialization of the system. 

SULFUR CYCLE HYDROGEN PRODUCTION PROCESS DEVELOPMENT AREAS... 

Sakuraia, M., Nakajimaa, H., Amirb, R., Onukia, K., and Shimizua, S., Experimental study on side-reaction occurrence condition in the iodine-sulfur thermochemical hydrogen production process. International Journal of Hydrogen Energy, 25, 613-619, 2000. 

The Hybrid Sulfur (HyS) thermochemical cycle task addresses the key technology issues involved in the development of a hybrid sulfur hydrogen production system - including the SO2 - H2O electrolyzer design, SO2/O2 separation, and the unique materials and process issues associated with the acid decomposition section. An electrolyser is being developed that can be used in conjunction with the sulfuric acid decomposition section being developed for the S-I cycle in a Hybrid Sulfur Integrated Laboratory-Scale Experiment. 

K. Onuki, H. Nakajima, M. Futakawa, I. loku and S. Shimizu, A study on the Iodine-Sulfur thermochemical hydrogen production process, Principle of Exergy Reproduction (No. 256) supported by the Grant-Aid on Priority Areas, Ministry of Education, JAPAN (1998). 

Sulfur) process [1] have been investigating for the thermochemical hydrogen production processes... 

The thermochemical and electrolytic hybrid hydrogen production process has been developed by Japan Nuclear Cycle Development Institute (JNC). The process is based on sulfuric acid (H2SO4) syntliesis and decomposition process developed earlier (Westinghouse process) and sulfur trioxide (SO,) decomposition process is facilitated by electrolysis with ionic oxygen conductive solid electrolyte at 500°C-550°C. Stable hydrogen and oxygen production for several hours by the process was already confirmed in the experiments performed by JNC. 

Electrochemical oxidation of aqueous SO2 on the electrode surface has also aroused interest in the large-scale hydrogen production processes via a hybrid sulfur cycle which was patented as Westinghouse Process. The electrochemical oxidation of aqueous sulfur dioxide with respect to the hybrid sulfur cycle has recently been reviewed and shown the importance of the mechanism of the oxidation of sulfur dioxide on the electrode surface. Platinum, gold, and carbon materials as electrocatalysts have been reviewed to compare the catalytic activity for SO2 oxidation [16]. The first step in the Westinghouse Process is the dissociation of H2SO4 into SO2 and O2 by thermal cracking at about 1,000 °C ... 

IS Iodine—sulfur cycle hydrogen production process... 

Tetrahydronaphthalene is produced by the catalytic treatment of naphthalene with hydrogen. Various processes have been used, eg, vapor-phase reactions at 101.3 kPa (1 atm) as well as higher pressure Hquid-phase hydrogenation where the conditions are dependent upon the particular catalyst used. Nickel or modified nickel catalysts generally are used commercially however, they are sensitive to sulfur, and only naphthalene that has very low sulfur levels can be used. Thus many naphthalene producers purify their product to remove the thionaphthene, which is the principal sulfur compound present. Sodium treatment and catalytic hydrodesulfuri2ation processes have been used for the removal of sulfur from naphthalene the latter treatment is preferred because of the ha2ardous nature of sodium treatment. 

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