Processes for desorption from LiAlO sub 2 treated with H sub 2 as studied by temperature programmed desorption
The energetics and kinetics of the evolution of H{sub 2}O and H{sub 2} from LiAlO{sub 2} are being studied by the temperature programmed desorption technique. The concentrations of H{sub 2}, H{sub 2}O, N{sub 2}, and O{sub 2} in a helium stream during a temperature ramp are measured simultaneously with a mass spectrometer. Blank experiments with an empty sample tube showed that square wave spikes of H{sub 2} introduced into the helium gas stream were severely distorted by reaction with the tube walls. The tube could be stabilized, however, by sufficiently prolonged heat treatment with H{sub 2} so that H{sub 2} peaks would not be distorted up to approximately 923 K(650{degree}C). The amount of H{sub 2}adsorption/desorption is small compared to the amount of H{sub 2}O adsorption/desorption. After prolonged treatment with helium containing 990 ppm H{sub 2} at 400{degree}C, H{sub 2}O evolution into the He-H{sub 2} stream was observed during 473 to 1023 K (200 to 750{degree}C) ramps at rates of 2 or 5.6 K/min. The different peak shapes reflecting this process were deconvoluted to show that they are composites of only 2 or 3 reproducible processes. The activation energies and pre-exponential terms was evaluated. The different behavior originates in the differences among different surface sites for adsorption. The interpretation of higher temperature peaks (above 873 K (650{degree}C)) must still consider the possibility of contributions from interactions with steel walls. It was found that H{sub 2} enhances evolution of N{sub 2} from the steel. 1 tab., 6 figs., 11 refs.
- Research Organization:
- Argonne National Lab., IL (USA)
- Sponsoring Organization:
- DOE/NE
- DOE Contract Number:
- W-31109-ENG-38
- OSTI ID:
- 6286255
- Report Number(s):
- CONF-901007-55; ON: DE91006623; TRN: 91-002150
- Resource Relation:
- Conference: 9. topical meeting on technology of fusion energy, Oak Brook, IL (USA), 7-11 Oct 1990
- Country of Publication:
- United States
- Language:
- English
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ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
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ALUMINIUM OXIDES
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TRITIUM
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NONMETALS
NUCLEAR FUEL CONVERSION
NUCLEI
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