Alpha-radiolysis of organic extractants for separation of actinides

Sugo, Yumi; Taguchi, Mitsumasa; Sasaki, Yuji  ; Hirota, Koichi; Morita, Yasuji  

Influence of coexisting oxygen on the radiolysis of organic extractants for the separation of actinides was investigated. -Tetraoctyldiglycolamide (TODGA) was dissolved in -dodecane, and purged with nitrogen or oxygen gas. The solution was irradiated with helium ions provided by a cyclotron accelerator in the TIARA facility. The concentration of TODGA in -dodecane after irradiation was measured using GC/FID. It was observed the yield for the degradation of TODGA in the presence of oxygen was slightly less than that in the nitrogen-saturated system. Next, a difference in the degradation products according to the existence of oxygen was examined by GC/MS analysis. A number of new peaks assigned to the oxidation products of -dodecane such as ketones and alcohols, were appeared only in the presence of oxygen. This result suggests the intermediate species of -dodecane such as radical cations are liable to react with oxygen. It is therefore considered that the yield for the degradation of TODGA is slightly reduced in the presence of oxygen.