scholarly journals Uranium(VI) reduction by nanoscale zero-valent iron in anoxic batch systems: The role of Fe(II) and Fe(III)

Chemosphere ◽  
2014 ◽  
Vol 117 ◽  
pp. 625-630 ◽  
Author(s):  
Sen Yan ◽  
Yongheng Chen ◽  
Wu Xiang ◽  
Zhengyu Bao ◽  
Chongxuan Liu ◽  
...  
Keyword(s):  
Zero Valent Iron ◽  
Batch Systems ◽  
Nanoscale Zero Valent Iron

Unveiling the Role of Sulfur in Rapid Defluorination of Florfenicol by Sulfidized Nanoscale Zero-Valent Iron in Water under Ambient Conditions

2021 ◽  
Vol 55 (4) ◽  
pp. 2628-2638
Author(s):  
Zhen Cao ◽  
Hao Li ◽  
Gregory V. Lowry ◽  
Xiaoyang Shi ◽  
Xiangcheng Pan ◽  
...  
Keyword(s):  
Zero Valent Iron ◽  
Ambient Conditions ◽  
Nanoscale Zero Valent Iron

Transport of sucrose-modified nanoscale zero-valent iron in saturated porous media: role of media size, injection rate and input concentration

2015 ◽  
Vol 72 (9) ◽  
pp. 1463-1471 ◽  
Author(s):  
Hui Li ◽  
Yong-sheng Zhao ◽  
Zhan-tao Han ◽  
Mei Hong
Keyword(s):  
Porous Media ◽  
Packed Column ◽  
Injection Rate ◽  
Zero Valent Iron ◽  
Silica Sand ◽  
Saturated Porous Media ◽  
Input Concentration ◽  
K Value ◽  
Nanoscale Zero Valent Iron

The growing use of nanoscale zero-valent iron (NZVI) in the remediation of contaminated groundwater raises concerns regarding its transport in aquifers. Laboratory-scale sand-packed column experiments were conducted with bare and sucrose-modified NZVI (SM-NZVI) to improve our understanding of the transport of the nanoparticles in saturated porous media, as well as the role of media size, suspension injection rate and concentration on the nanoparticle behavior. As the main indicative parameters, the normalized effluent concentration was measured and the deposition rate coefficient (k) was calculated for different simulated conditions. Overall, compared to the high retention of bare NZVI in the saturated silica column, SM-NZVI suspension could travel through the coarse sand column easily. However, the transport of SM-NZVI particles was not very satisfactory in a smaller size granular matrix especially in fine silica sand. Furthermore, the value of k regularly decreased with the increasing injection rate of suspension but increased with suspension concentration, which could reflect the role of these factors in the SM-NZVI travel process. The calculation of k-value at the tests condition adequately described the experimental results from the point of deposition dynamics, which meant the assumption of first-order deposition kinetics for the transport of NZVI particles was reasonable and feasible.

scholarly journals The Removal of Uranium onto Nanoscale Zero-Valent Iron Particles in Anoxic Batch Systems

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Richard A. Crane ◽  
Thomas B. Scott
Keyword(s):  
Dissolved Oxygen ◽  
Mine Water ◽  
Inductively Coupled Plasma ◽  
Corrosion Behaviour ◽  
Zero Valent Iron ◽  
Iron Particles ◽  
Near Surface ◽  
Batch Systems ◽  
Batch System ◽  
Nanoscale Zero Valent Iron

The removal of uranium (U) onto nanoscale zero-valent iron particles has been studied for uranium-bearing mine water and synthetic uranyl solutions in the presence and absence of dissolved oxygen. The work has been conducted in order to investigate the differential nanoparticle corrosion behaviour and associated mechanisms of U removal behaviour in conditions representative of near-surface and deep groundwater systems. Batch systems were analysed over a 28-day reaction period during which the liquid and nanoparticulate solids were periodically analysed to determine chemical evolution of the solutions and particulates. Analysis of aqueous samples using inductively coupled plasma mass spectrometry recorded near-total U removal after 1 hour of reaction in all systems studied. However, in the latter stages of the reaction (after 48 hours), significant rerelease of uranium was recorded for the mine water batch system with dissolved O2present. In contrast, less than 2% uranium rerelease was recorded for the anoxic batch system. Concurrent analysis of extracted nanoparticle solids using X-ray diffraction recorded significantly slower corrosion of the nanoparticles in the anoxic batch system, with residual metallic iron maintained until after 28 days of reaction compared to only 7 days of reaction in systems with dissolved O2present. Results provide clear evidence that the corrosion lifespan and associated U6+removal efficacy of nanoscale zero-valent iron replace enhanced in the absence of dissolved oxygen.

Role of sulfide-modified nanoscale zero-valent iron on carbon nanotubes in nonradical activation of peroxydisulfate

2022 ◽  
Vol 422 ◽  
pp. 126949
Author(s):  
Libin Wu ◽  
Qintie Lin ◽  
Hengyi Fu ◽  
Haoyu Luo ◽  
Quanfa Zhong ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Zero Valent Iron ◽  
Nanoscale Zero Valent Iron

Role of oxidative stress in inactivation of Escherichia coli BW25113 by nanoscale zero-valent iron

2016 ◽  
Vol 565 ◽  
pp. 857-862 ◽  
Author(s):  
Krittanut Chaithawiwat ◽  
Alisa Vangnai ◽  
John M. McEvoy ◽  
Birgit Pruess ◽  
Sita Krajangpan ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Escherichia Coli ◽  
Zero Valent Iron ◽  
Nanoscale Zero Valent Iron

scholarly journals Remediation of Cd-Contaminated Soil by Modified Nanoscale Zero-Valent Iron: Role of Plant Root Exudates and Inner Mechanisms

2021 ◽  
Vol 18 (11) ◽  
pp. 5887
Author(s):  
Danlian Huang ◽  
Yunhe Yang ◽  
Rui Deng ◽  
Xiaomin Gong ◽  
Wei Zhou ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Root Exudates ◽  
Contaminated Soil ◽  
Great Influence ◽  
Zero Valent Iron ◽  
High Concentration ◽  
Soil Microbial Community Structure ◽  
Nanoscale Zero Valent Iron ◽  
Cd Removal

In this study, the role of exogenous root exudates and microorganisms was investigated in the application of modified nanoscale zero-valent iron (nZVI) for the remediation of cadmium (Cd)-contaminated soil. In this experiment, citric acid (CA) was used to simulate root exudates, which were then added to water and soil to simulate the pore water and rhizosphere environment. In detail, the experiment in water demonstrated that low concentration of CA facilitated Cd removal by nZVI, while the high concentration achieved the opposite. Among them, CA can promote the adsorption of Cd not only by direct complexation with heavy metal ions, but also by indirect effect to promote the production of iron hydroxyl oxides which has excellent heavy metal adsorption properties. Additionally, the H+ dissociated from CA posed a great influence on Cd removal. The situation in soil was similar to that in water, where low concentrations of CA contributed to the immobilization of Cd by nZVI, while high concentrations promoted the desorption of Cd and the generation of CA–Cd complexes which facilitated the uptake of Cd by plants. As the reaction progressed, the soil pH and cation exchange capacity (CEC) increased, while organic matter (OM) decreased. Meanwhile, the soil microbial community structure and diversity were investigated by high-throughput sequencing after incubation with CA and nZVI. It was found that a high concentration of CA was not conducive to the growth of microorganisms, while CMC had the effect of alleviating the biological toxicity of nZVI.

Sign in / Sign up

Export Citation Format

Share Document