Hydrogen production in gamma radiolysis of the mixture of mordenite and seawater

Abstract

Hydrogen production by g-radiolysis of the mixture of mordenite, a zeolite mineral, and seawater was studied in order to provide basic points of view for the influences of zeolite minerals, of the salts in seawater, and of rise in temperature on the hydrogen production by the radiolysis of water. These influences are required to be considered in the evaluation of the hydrogen production from residual water in the waste zeolite adsorbents generated in Fukushima Dai-ichi Nuclear Power Station. As the influence of the mordenite, an additional production of hydrogen besides the hydrogen production by the radiolysis of water was observed. The additional hydrogen can be interpreted as the hydrogen production induced by the absorbed energy of the mordenite at the yield of 2.3610 78 mol/J. The influence of the salts was observed as increase of the hydrogen production. The influence of the salts can be attributed to the reactions of bromide and chloride ions inhibiting the reaction of hydrogen with hydroxyl radical. The influence of the rise in temperature was not significantly observed up to 608C in the mixture with seawater. The results show that the additional production of hydrogen due to the mordenite had little temperature dependence.

On the hydrogen production of geopolymer wasteforms under irradiation

“…This production efficiency was even inducing a maximum hydrogen yield of the overall system larger for a partially dried zeolite than for a water saturated one. In other studies with zeolites immerged in water, an excess of production was also observed but with a linear evolution with the water content. This is consistent with previous interpretations with geopolymers as, after saturation, no new interface is created between the solid and the water and there is no modification in hydrogen production in the bulk water, as long as the water is far enough from the solid particle.…”

Hydrogen generation by water radiolysis with immersion of oxidation products of Zircaloy-4

“…where G ox is hydrogen-generation term originated from the energy deposition to the oxide or the oxidation product [12]. The f w and f ox are the absorbed fractions of water and solid, respectively, corresponding to the fractions of energies deposited to them (f w + f ox = 1).…”

Early construction and operation of the highly contaminated water treatment system in Fukushima Daiichi Nuclear Power Station (IV) - Assessment of hydrogen behavior in stored Cs adsorption vessel

“…The generation rate of hydrogen can be predicted using linear energy transfer and g-value. Kumagai et al [8,9] estimated hydrogen gas production of 1.5 L/h in a Kurion vessel containing 7.38 mol of Cs based on the measured g-values for the γ -irradiation of the mixture of seawater and zeolite. As the amount of Cs uptake in their calculation was far larger than that of actual operation, hydrogen generation rate was calculated to be 0.36 L/h for nominal case and 0.72 L/h for maximum case.…”