Synthesis of Naphthalimidedioxime Ligand-Containing Fibers for Uranium Adsorption from Seawater

Abstract

A novel ligand-functionalized adsorbent material was prepared using a combination of radiation-induced graft polymerization (RIGP) and click chemistry (1,3 cycloaddition reaction). The design of the ligand-containing amidoxime functionality is based on its chelating efficiency with uranium. In this process, RIGP is used to graft polymer chains on fiber substrates, where the fibers are prepared by irradiating and treating polyethylene (PE) with different bulk ratios of vinyl benzyl chloride and acrylic acid or itaconic acid. Furthermore, chemical modifications of these fibers are performed using a two-step process, where novel bisimidoxime ligands are incorporated into fibers. These ligands contain imidedioxime, which is known to be a uranophile. Also, the core structure of the ligand containing three donor atoms facilitates the formation of chelate with uranyl ion in media such as seawater. Density functional theory calculations were performed to quantify the binding strength with the uranyl ion. When tested with simulated seawater with a uranium concentration of 6 ppm at pH 8.0−8.3, the developed materials showed moderate to high uranium (∼35−50 g U/kg adsorbent) adsorption capacity.

Significantly Enhanced Uranium Extraction from Seawater with Mass Produced Fully Amidoximated Nanofiber Adsorbent

“…[3,[20][21][22][23][24][25] However, in this study, we found that 10 × 10 −3 m NaOH solution is enough to "active" the imide dioxime and/or amidoxime groups sufficiently. In most of the previous studies, 0.44 m NaOH (or KOH) solution was generally used for the alkaline treatment of adsorbent fibers prepared by RIGP or ATRP from PE trunk fibers.…”

“…Great efforts have been made to develop clean energy as alternatives to fossil fuels. [19][20][21][22][23][24][25][26][27] Very recently, Cui and co-workers reported the application of an amidoxime-functionalized electrode in a half-wave rectified alternating current electrochemical (HW-ACE) method for the extraction of uranium from seawater. [3] With DOE direction, the uranium uptake capacity of fiber adsorbents in natural seawater has more than tripled in five years.…”

Functionalized Sugarcane Bagasse for U(VI) Adsorption from Acid and Alkaline Conditions

“…However, few adsorbent could be applied in all of mine tailings effluent, radioactive wastewater and seawater. The extraction is limited by some reasons: (1) aqueous uranium species is various, such as cationic UO 2 2+ , UO 2 OH + and (UO 2 ) 2 (OH) 2+ in mine tailings effluent and radioactive wastewater 34 , 35 and anionic [UO 2 (CO 3 ) 3 ] 4− in seawater 36 , 37 , (2) the concentration of uranium is in a wide range concentrations (mg/L-μg/L), (3) there are large amount of competing metal ions, such as sodium, potassium, magnesium and calcium, and (4) adsorbent should have a great chemical and structural stability in both acidic (mine tailings effluent and radioactive wastewater) and alkaline (seawater) environment. Therefore, an adsorbent with remarkable adsorption properties and stability is necessary.…”

A polyethersulfone–bisphenol sulfuric acid hollow fiber ultrafiltration membrane fabricated by a reverse thermally induced phase separation process

“…Click chemistry offers a terric way for membrane modication. [24][25][26][27][28] The prominent merits of click chemistry are its capacity to supply superior site selectivity, which can provide almost quantitative conversion under mild condition and with almost no side reaction or by-product. [29][30][31] Ge et al 32 constructed an ionic highway in the anion-exchange membrane by click chemistry and synthesized a novel AEMs material.…”