Collection of Lanthanides and Actinides from Natural Waters with Conventional and Nanoporous Sorbents

Abstract

Effective collection of trace-level lanthanides and actinides is advantageous for recovery and recycling of valuable resources, environmental remediation, chemical separations, and in situ monitoring. Using isotopic tracers, we have evaluated a number of conventional and nanoporous sorbent materials for their ability to capture and remove selected lanthanides (Ce and Eu) and actinides (Th, Pa, U, and Np) from fresh and salt water systems. In general, the nanostructured materials demonstrated a higher level of performance and consistency. Nanoporous silica surface modified with 3,4-hydroxypyridinone provided excellent collection and consistency in both river water and seawater. The MnO(2) materials, in particular the high surface area small particle material, also demonstrated good performance. Other conventional sorbents typically performed at levels below the nanostructured sorbents and demonstrate a larger variability and matrix dependency.

Positively charged phosphonate-functionalized mesoporous silica for efficient uranium sorption from aqueous solution

“…For this purpose, numerous techniques have been adopted, including coprecipitation [5], solvent extraction [6], membrane filtration [7], and sorption [8,9]. Among them, sorption offers several benefits such as simple operation, low cost, and easy recycling [10].…”

Model studies on the separation of Ca2+ and Nd3+ ions using ethylenediaminetetraacetic acid

“…However, the China export used to be limited to 40% in 2012. This may cause serious problems for technologies outside of China, hence alternative RE sources, are being searched for [14][15][16][17][18]. One of the possible sources can be phosphogypsum which is a by-product (End-of-Life material) in the process of phosphoric acid production from phosphate rocks, phosphorites and apatites, by the wet method.…”

Synthesis of polyamidoxime-functionalized nanoparticles for uranium(VI) removal from neutral aqueous solutions

“…Uranium(VI), an element associated with nuclear energy and weapons, possesses high chemical toxicity, long halflife radioactivity, and high levels of mobility in the environment, which may pollute the environment and endanger human's health [1,2]. In the past decades, many methods have been developed for uranium(VI) removal from aqueous solutions [3][4][5][6][7][8][9][10][11] ,such as ionic exchange, chemical precipitation [12,13], membrane dialysis [14], flotation [15,16], bio-concentration [17], liquid-liquid extractions [18,19], solid-liquid separation [5,20,21].…”