Fuel Reprocessing Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India.
J Hazard Mater. 2012 Oct 30;237-238:339-46. doi: 10.1016/j.jhazmat.2012.08.055. Epub 2012 Aug 31.
Transport behaviour of actinides viz. Am(3+), Pu(4+) and UO(2)(2+) was investigated from nitric acid feed conditions using PTFE (polytetrafluoroethylene) flat sheet supported liquid membranes (SLM) containing an irradiated solvent system comprising of N,N,N',N'-tetra-n-octyldiglycolamide (TODGA) as the carrier extractant and N,N-di-n-hexyloctanamide (DHOA) as the phase modifier. The present studies were carried out in order to understand the effect of irradiation on the long term reusability of the SLM and the decontamination behaviour in the absorbed dose range of 0-100 MRad. The studies using irradiated carrier included those with irradiated TODGA without any phase modifier and with 0.1M as well as 0.5M DHOA as the phase modifier. Transport behaviour of all the metal ions were found to be seriously affected with increasing radiation dose which was reflected in the decreasing percentage transport (%T) as well as permeability co-efficient (P) values. Though Sr(II) transport was quite significant with all the three unirradiated solvent systems, it was surprisingly low (<5%) when solvents exposed to 100 MRad dose were used in the SLM. Separation factors (S.F.) of the actinides over Sr(II) were calculated and were found to increase at higher radiation doses suggesting possibility of getting better decontamination on prolonged use of the supported liquid membrane system.
采用含有辐照溶剂体系的聚四氟乙烯(PTFE)平板支撑液膜(SLM)研究了钍(3+)、钚(4+)和 UO2(2+)的传质行为,该溶剂体系由 N,N,N',N'-四正辛基二甘酰胺(TODGA)作为载体萃取剂和 N,N-二正辛基己酰胺(DHOA)作为相调节剂组成。本研究旨在了解辐照对 SLM 的长期重复使用性能的影响以及在 0-100 MRad 吸收剂量范围内的去污行为。使用辐照载体的研究包括没有任何相调节剂的辐照 TODGA 以及含有 0.1M 和 0.5M DHOA 的相调节剂。所有金属离子的传质行为都发现随着辐射剂量的增加而受到严重影响,这反映在传质百分比(%T)和渗透率(P)值的降低。尽管所有三种未辐照溶剂体系中 Sr(II)的传输都相当显著,但当在 SLM 中使用暴露于 100 MRad 剂量的溶剂时,其传输率却低得惊人(<5%)。计算了锶(II)的锕系元素分离因子(S.F.),发现随着辐射剂量的增加而增加,这表明在延长支撑液膜系统的使用时间后,有可能获得更好的去污效果。