Fractional Elution and Determination of Uranium and Vanadium Adsorbed on Amidoxime Fiber from Seawater

Abstract

Uranium is one of the most valuable metals in seawater. Various inorganic and organic adsorbents for the recovery of uranium in seawater have so far been synthesized and evaluated. [1][2][3][4] Among the adsorbents reported, amidoxime polymers are noted as being the most promising. 1,3,4 Hirotsu et al. 5,6 have already investigated a separative elution of uranium from an amidoxime polymer which had been immersed in seawater, and proposed the selective elution of uranium from an amidoxime polymer with 0.5 or 1 mol dm -3 hydrochloric acid after complete elution of co-adsorbed magnesium(II), calcium(II), zinc(II), and nickel(II) with 0.1 mol dm -3 hydrochloric acid. However, the fraction of uranium also contained iron(III) and copper(II), which have had to be removed in the succeeding step, and no information about the adsorption and elution of vanadium was given in the work by Hirotsu et al. 5,6 We undertook the present work to obtain further information about the characteristics of the amidoxime polymer, and explored a method to elute iron and copper adsorbed on the amidoxime fiber from seawater prior to the release of uranium. Furthermore, we also found that vanadium adsorbed strongly on amidoxime fiber, and established a procedure to recover vanadium quantitatively from it.

Adsorption Efficiency of a New Adsorbent Towards Uranium and Vanadium Ions at Low Concentrations

“…A comparative evaluation was made to see the uranyl ion adsorption capacity of various adsorbents developed by different groups and the new adsorbent developed by our group. Adsorbent systems listed in Table 1 include only those based on et al [25] Lightly cross-linked poly(acrylonitrile-co-divinylbenzene) 0.650 mg/g U 0.65 mg/g Suzuki d et al [26] Polypropylene nonwoven fabric grafted with acrylonitrile and methacrylic acid 0.576 mg/g U 1.8 mg/g V 0.576 mg/g U 1.8 mg/g V Kawai e et al [14] Polypropylene fiber cografted with methacrylic acid and acryloylchloride…”

05/02504 Performance of three resin-based materials for treating uranium-contaminated groundwater within a PRB

“…Thus it is suggested that PANSIL is also able to act as a ligand to neutral uranyl species. Such behaviour is not unexpected as amidoxime fibres have been shown to preferentially adsorb uranium from seawater [17], which has a pH of ~8.…”

Extraction of Uranium from Seawater: Design and Testing of a Symbiotic System

“…Suzuki et al 19 demonstrated that significant amount of Vanadium was adsorbed alongside the uranium by amidoxime polymers. To extract Vanadium and free the adsorbent functional groups, the concentration of the hydrochloric acid elution solution has to be increased by almost two orders of magnitude compared to what is necessary for uranium extraction 19 .…”

“…To extract Vanadium and free the adsorbent functional groups, the concentration of the hydrochloric acid elution solution has to be increased by almost two orders of magnitude compared to what is necessary for uranium extraction 19 . It is therefore likely that most of the elution damage comes from the removal of Vanadium.…”