The reaction of nuclear graphites with hydrogen

✍ Scribed by Hisashi Imai; Shinzo Nomura; Yasuichi Sasaki

• Publisher: Elsevier Science
• Year: 1975
• Tongue: English
• Weight: 433 KB
• Volume: 13
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(75)90039-1

✦ Synopsis

The corrosion reactions of various nuclear graphites with hydrogen were studied in the temperature range 970-1090°C at hydrogen partial pressures between 7 and 48 torr in helium stream of total pressure of 1 atm. Methane was the only gaseous product found in this reaction. The rates of corrosion reaction were found to be IO-' -10m2 yg/cm* hr on the basis of methane yield at 28 torr hydrogen pressure at 1025°C. The influence of the hydrogen partial pressure on the methane production rate is expressed as: R = K(PH2)"2. The apparent activation energy for the reaction was found to be 22 kcal/mol, independent of the impurity content of the graphite. No clear correlations were found between the production rate of methane and the total ash content in the graphite, its degree of crystallinity (determined by X-ray diffraction) and its degree of graphitization (infered from butanol immersion density).