Illite-supported nanoscale zero-valent iron for removal of 238U from aqueous solution: characterization, reactivity and mechanism

Abstract

In this work, illite was used to support zerovalent iron nanoparticles to remove 238 U in aqueous solutions. Compared to nZVI, I-nZVI shows high stability and removal efficiency. Removal process of U on I-nZVI can be concluded into four stages in illite dominated zone, Fe 0 released zone, ferrous dominated zone and reaction equilibrium zone. The study shows that illite is a good dispersant and stabilizer which decreases the aggregation of nZVI and improves the activity of Fe 0 . Removal capacity of U on I-nZVI achieves 1.79 lg/mg. I-nZVI is an efficient and promising remediation material for waste-soluble uranium compounds.

Characterization of green zero-valent iron nanoparticles produced with tree leaf extracts

“…Then the tested amount of iron (III) was decreased and the tests were performed until the settlement was observed at least after 90 min. The nZVI is highly reactive within the first 1-2 h, after which the surface of the particles is mostly oxidized and has a reduced reactivity (Jing et al, 2015). This test allows the identification of when and at what concentration the nZVI starts to settle.…”

X-ray absorption fine structure study of enhanced sequestration of U(vi) and Se(iv) by montmorillonite decorated with zero-valent iron nanoparticles

“…This is a general phenomenon where NZVI displays a much higher reactivity than ZVI does due to the lower particle size and larger surface area. [51][52][53][54][55][56][57][58][59][60][61] Besides, in previous reports, it was regarded that gas bubbles (likely H 2 ) could be generated in the NZVI reaction system, and the rapid formation of H 2 might enhance the performance of UIJVI) and SeIJIV) sequestration, while these gas bubbles could not be observed in the ZVI reaction system, hence UIJVI) and SeIJIV) sequestration onto ZVI can not be enhanced. Using NaBH 4 as a reductant, during the synthesis of NZVI, the reduction product (i.e.…”

“…41 Hence, intensive efforts have been devoted to the development of new forms of supported NZVI particles. Consequently, a large number of porous supports like sepiolite, 40 zeolite, 41 resin, 42,43 mesoporous silica, 44,45 diatomite, [46][47][48] bentonite, [49][50][51][52] illite, 53 smectite, 54 rectorite, 55 montmorillonite, 41,[56][57][58] MgIJOH) 2 , 59 layered double hydroxides, 60,61 and carbon-based nanomaterials [61][62][63][64][65][66][67] have been employed to increase the durability, reactivity and mechanical strength of NZVI and these supported NZVI materials exhibited a much higher rate and efficiency in contaminant sequestration from aqueous solutions, compared with that of bare NZVI.…”

“…Clay mineral is an enormously abundant natural resource and has been regarded as a class of suitable supports due to its potential applicability in environmental pollution control. [49][50][51][52][53][54][55] Montmorillonite (Mont) is one of the most expandable clay minerals characterized by its laminar organization, consisting of two tetrahedral layers of silica and a central octahedral layer of aluminum oxide. 41 This material has been widely used in the sequestration of metal ions from aqueous solutions, which occurs following two mechanisms, i.e.…”

The Removal Mechanism of U(VI) on nZVI/MoS2 Composites Investigated by Batch, Spectroscopic, and Modeling Techniques

“…With the rapid development of industrialization and civilization, nuclear energy has been widely used in many countries whereas the increasing production of radionuclides has attracted public attention due to their strong radioactivity and bioaccumulation . The post-process of spent fuel leads to the release of various radionuclides into the subsurface environment, which unpredictably threatens ecological diversity, water security, and human public health. , Uranium as one of the basic raw materials of nuclear energy exhibits two oxidized states, namely, dissolved U­(VI) and sparingly dissolved U­(IV). , Therefore, it is extremely necessary and urgent to remove U­(VI) from the environment using effective technologies because of its high chemical toxicity and long half-life (4.5 billion years). − The reduction of water-soluble U­(VI) to insoluble U­(IV) (i.e., precipitated UO 2 ) is an effective method to eliminate U­(VI) from wastewater. − …”