'water splitting' by titanium exchanged zeolite A. Technical report

Technical Report · Fri Sep 01 00:00:00 EDT 1978

OSTI ID:6242231

Kuznicki, S M; Eyring, E M

Visually detectable and chromatographically and mass spectrally identified hydrogen gas evolves from titanium (III) exchanged zeolite A immersed in water and illuminated with visible light. Titanium(III) exchanged zeolite X and zeolite Y do not produce this reaction. A photochemically produced, oxygenated titanium free radical (detected by electron spin resonance) not previously described is the species in the zeolite that reduces protons to molecular hydrogen. The other product of this reduction step is a nonradical, oxygenated titanium species of probable empirical formula TiO4. Heating the spent oxygenated titanium containing zeolite A under vacuum at 375 C restores over fifty percent of the free radical. Unlike previously reported systems, heating does not restore the original aquotitanium(III) species in the zeolite. Thus a means other than heating must be found to achieve a closed photochemical cycle that harnesses visible solar energy in the production of molecular hydrogen. The titanium exchanged zeolite A does, however, lend itself to a thermolysis of water previously described by Kasai and Bishop. (Author)

• Research Organization: Utah Univ., Salt Lake City (USA). Dept. of Chemistry
• DOE Contract Number: N00014-75-C-0796
• OSTI ID: 6242231
• Report Number(s): AD-A-059131
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
HYDROGEN PRODUCTION
ION EXCHANGE
OXYGEN
PHOTOLYSIS
TITANIUM OXIDES
WATER
ZEOLITES
CHALCOGENIDES
CHEMICAL REACTIONS
CRYOGENIC FLUIDS
DECOMPOSITION
ELEMENTS
FLUIDS
HYDROGEN COMPOUNDS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
MINERALS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
080100* - Hydrogen- Production
400105 - Separation Procedures