4088-41-9Relevant academic research and scientific papers
Gamma-radiolytic stability of new methylated TODGA derivatives for minor actinide recycling
Galn, Hitos,Zarzana, Christopher A.,Wilden, Andreas,Nez, Ana,Schmidt, Holger,Egberink, Richard J. M.,Leoncini, Andrea,Cobos, Joaqun,Verboom, Willem,Modolo, Giuseppe,Groenewold, Gary S.,Mincher, Bruce J.
, p. 18049 - 18056 (2015/10/28)
The stability against gamma radiation of MeTODGA (methyl tetraoctyldiglycolamide) and Me2TODGA (dimethyl tetraoctyldiglycolamide), derivatives from the well-known extractant TODGA (N,N,N′,N′-tetraoctyldiglycolamide), were studied and compared. Solutions of MeTODGA and Me2TODGA in alkane diluents were subjected to 60Co γ-irradiation in the presence and absence of nitric acid and analyzed using LC-MS to determine their rates of radiolytic concentration decrease, as well as to identify radiolysis products. The results of product identification from three different laboratories are compared and found to be in good agreement. The diglycolamide (DGA) concentrations decreased exponentially with increasing absorbed dose. The MeTODGA degradation rate constants (dose constants) were uninfluenced by the presence of nitric acid, but the acid increased the rate of degradation for Me2TODGA. The degradation products formed by irradiation are also initially produced in greater amounts in acid-contacted solution, but products may also be degraded by continued radiolysis. The identified radiolysis products suggest that the weakest bonds are those in the diglycolamide center of these molecules.
Hydrolysis and radiation stability of m-xylylene bis-diglycolamide: Synthesis and quantitative study of degradation products by HPLC-APCI +
Galan, Hitos,Murillo, Maria Teresa,Sedano, Rosa,Nunez, Ana,De Mendoza, Javier,Gonzalez-Espartero, Amparo,Prados, Pilar
experimental part, p. 3959 - 3969 (2011/09/15)
For nuclear hydrometallurgical separation process development, it is necessary to demonstrate the stability of the extracting systems, since it is well known that radio- and hydrolytic degradation leads to undesirable effects, such as a decrease in selectivity, poorer phase separation and third-phase formation. Recently, we have developed a new family of bis-diglycolamide (bis-DGA) molecules with high distribution coefficients (D) for EuIII over AmIII. One of these bis-DGA extractants, namely, compound 1, showed high distribution coefficients even under gamma irradiation at 1000 kGy with external 60Co sources. We report herein a detailed account on the stability of 1 against radio- and hydrolysis. We have also identified and quantified the sub-products formed during the irradiation process. Qualitative and quantitative analyses of irradiated 1 were performed by HPLC-MS, indicating the presence of seventeen degradation compounds. All fragments (2-18) were identified and synthesized independently. To complete this study, the An III and LnIII extraction properties of these fragments were assessed under the same experimental conditions as those used to evaluate the AnIII and LnIII extraction by irradiated 1. Despite the significance of a decrease in the concentration of 1, Am/Eu D values are still quite high. This means that at least some degradation products also act as efficient extractants. It is relevant to remark that two of the major degradation products (compounds 3 and 11) are stable to radiation and showed high D values for AmIII and EuIII extraction. Compound 1, an extractant of AmIII and EuIII from nuclear waste, was irradiated with γ irradiation at 1000 kGy with external 60Co sources, resulting in 17 subproducts. These compounds were synthesized and qualitative and quantitative analyses of irradiated 1 were performed. Two of the major degradation products were stable to radiation and showed high D values for AmIII and EuIII extraction. Copyright
