A review of anthropogenic radionuclide 236U: Environmental application and analytical advances

Engineered Sorbents for Selective Uranium Sequestration from Seawater

“…Inorganic materials, including graphene, mesoporous carbon and silica, have been thoroughly studied as efficient sorbents for U removal from aqueous solutions. − These materials have remarkable properties, such as strong durability, high surface area, affordability, and eco-friendliness. However, the limitations of inorganic compounds, particularly their poor selectivity, emphasize the need to explore functionalized materials with improved selectivity and sorption capabilities.…”

“…Graphene-based sorbents have gained increasing attention as promising materials for efficient and selective extraction of various ions from seawater. − A hydrogenated form of graphene exhibits an excellent thermal and chemical stability, as well as a high surface area, making it an attractive candidate for sorption applications. − Similar to the layered double hydroxides (LDHs), graphene-based sorbents possess interlayer spaces that allow efficient ion exchange, enabling the selective removal of contaminants from seawater. Recently, there has been a growing interest in using graphene oxide (GO) based materials/sorbents for the removal of U salts from seawater. , The GO-based nanocomposites (with large surface area) are highly functionalized materials and can be modified to incorporate different functional groups to expand their application.…”

“…Among several methods developed for UES, the synthesis and application of various sorbents using innovative strategies have been highly explored and put forward. − Over the time span of decades, several materials have been synthesized and tested for UES. Recently, the focus has been intensified toward the synthesis and application of porous materials such as metal–organic frameworks (MOFs), covalent organic frameworks (COFs), membranes, and hydrogels as suitable candidates for extraction of U from natural seawater. − Additionally, the researchers have reported synthesis and application of graphene- and silica-based (composite) sorbents for U extraction under the defined/optimized experimental conditions. − …”

Atomic spectrometry update – a review of advances in environmental analysis

“…Reviews on digestion and extraction methods included 111 one (101 references) on rapid alkali-fusion methods for determining anthropogenic 236 U in soil that could provide results quickly following nuclear incidents. Automatic flow-analysis systems and potential application to multi-nuclide analysis were also addressed.…”

Simple and convenient preconcentration procedure for the isotopic analysis of uranium in seawater

“…Recently, as an alternative strategy, the measurement of 236 U/ 238 U has been used to clarify the origins of contamination. 1–3 This has arisen because the rate of production of 236 U in the environment is extremely low and the natural background level of this isotope is typically 10 −14 to 10 −12 in 236 U/ 238 U, 4 which is about 3–7 orders of magnitude lower compared with that of anthropogenic levels of U. However, the ratio of anthropogenic 236 U/ 238 U is susceptible to dilution by the addition of naturally occurring 238 U from the environment; 5 nevertheless, sometimes knowledge regarding the sources of U can be elusive based on the measurement of the 236 U/ 238 U ratio.…”