Preparation of hydrophilic amidoxime fibers by cografting acrylonitrile and methacrylic acid from an optimized monomer composition

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…”

“…[3 -5] Sekiguchi et al and Kawai et al investigated the separative elution of uranium ions from an amidoxime polymer that had been immersed in seawater. [13,14] A number of papers published by Güven et al investigated the preparation and properties of new copolymers with balanced hydrophilic and amidoxime group contributions for the uptake of uranyl ions from aqueous solutions. [15 -18] Kise et al [19] and Park et al [20] synthesized polystyrene-based chelating resins with a pair of amidoxime groups per repeating styrene units on polystyrene, in a geminate position, which could effectively coordinate to uranyl ions, by higher concentration of amidoxime groups.…”

Recent International R&D Activities in the Extraction of Uranium from Seawater

“…Both laboratory studies and marine experiments in the Pacific Ocean have been conducted. The laboratory studies cover the preparation of amidoxime-based adsorbents, the equilibrium of the uranium uptake, and the kinetics and mechanism of the extraction of uranium from seawater (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16). Collection of uranium with chitosan-resin and biomass such as algae was also performed (17,18).…”

“…Previous studies aiming at improving the sorption kinetics include the preparation of hydrophilic amidoxime fibers by co-grafting multiple ligands (9), the preparation of hydrogels containing various acidic ligands (24) and the use of cellulose or cellulose-like materials (e.g., chitosan Figure 9) (17). The rapid advances of nanotechnology in recent years are expected to help develop novel materials for applications in the collection of uranium in seawater.…”

Radiation‐induced graft polymerization of glycidyl methacrylate onto PE/PP nonwoven fabric and its modification toward enhanced amidoximation

“…Conventionally, amidoxime group-containing adsorbents are synthesized through the reaction of acrylic resins and hydroxylamine. The acrylic resin used is generally made from a copolymer of acrylonitrile and crosslinked monomer such as divinyl benzene, which has been extensively studied by Okamato et al 6 and Omichi et al 7 Amidoxime chelate fibers have been presented by Sugo et al [8][9][10] and Lin et al 11 and found it to be very useful for recovering uranium from seawater and enriching or separating noble metal ions from aqueous systems. Various attempts have also been made to introduce hydrophilic monomers, and enhancement of uranyl selectivity into copolymeric adsorbents by Gü ven et al [12][13][14][15] Work on fibrous systems has generated wide interest in the last decade because of improvements with respect to flow rate through such porous adsorbents and the mechanical stability of the fibers.…”