Research on Foam’s Carrying Capacity of Two Types of nZVI

2017 ◽  
Vol 744 ◽  
pp. 536-541 ◽  
Author(s):  
Lan Xiang Shi ◽  
Jia Jun Chen ◽  
Meng Wei ◽  
Yun Song Liu
Keyword(s):  
Carrying Capacity ◽  
Environmental Remediation ◽  
Organic Pollutant ◽  
Zero Valent Iron ◽  
Precipitation Method ◽  
Sweep Efficiency ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Nanoscale Zero Valent Iron ◽  
The Stability

Special physical and chemical properties of nanoscale zero valent iron (nZVI), such as small particle size and high reactivity, make it a good choice as a remediation agent. nZVI is widely used in the remediation of various contaminants, including heavy metals and persistent organic pollutant. However, the immobilization of nanoparticles in porous medium limits the application in soil environmental remediation. Foam instead of water is used as the carrier of nanoparticles in in-site soil remediation process, which is a new idea, to improve sweep efficiency of nanoparticles. In this paper, the foam’s carrying ability of two types of nanoscale zero valent iron is studied. One of nZVI is purchased from a reagent Company, the other one is obtained by chemical precipitation method. In addition, the influence factors, the type and concentration of surfactant, foam quality and the initial concentration of nZVI are also discussed. The results demonstrate that foam has a 73% carrying capacity of nZVI-M, while much less capacity (33%) of nZVI-P under certain conditions. Surfactant can be used as dispersant to improve the stability of nZVI suspension. Besides, nZVI has no significant effect on the stability of foam, which provide the premise for foam as carrier. Influencing degree of these factors followed the order of the surfactant type > surfactant concentration > initial concentration of nZVI > foam quality under the experimental conditions.

Strategies to enhance the stability of nanoscale zero-valent iron (NZVI) in continuous BrO3− reduction

2019 ◽  
Vol 231 ◽  
pp. 714-725 ◽  
Author(s):  
Shanawar Hamid ◽  
Damira Abudanash ◽  
Seunghee Han ◽  
Jong R. Kim ◽  
Woojin Lee
Keyword(s):  
Zero Valent Iron ◽  
Nanoscale Zero Valent Iron ◽  
The Stability

Degradation of bromamine acid by nanoscale zero-valent iron (nZVI) supported on sepiolite

2012 ◽  
Vol 66 (12) ◽  
pp. 2539-2545 ◽  
Author(s):  
Xuening Fei ◽  
Lingyun Cao ◽  
Lifeng Zhou ◽  
Yingchun Gu ◽  
Xiaoyang Wang
Keyword(s):  
Ph Value ◽  
Energy Dispersive Spectrometer ◽  
Zero Valent Iron ◽  
Mass Ratio ◽  
Initial Concentration ◽  
Preparation Conditions ◽  
Transmission Electron ◽  
Nanoscale Zero Valent Iron ◽  
Initial Ph ◽  
Set Up

Sepiolite, a natural nano-material, was chosen as a carrier to prepare supported nanoscale zero-valent iron (nZVI). The effects of preparation conditions, including mass ratio of nZVI and activated sepiolite and preparation pH value, on properties of the supported nZVI were investigated. The results showed that the optimal mass ratio of nZVI and sepiolite was 1.12:1 and the optimal pH value was 7. The supported nZVI was characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and energy dispersive spectrometer (EDS), and furthermore an analogy model of the supported nZVI was set up. Compared with the nZVI itself, the supported nZVI was more stable in air and possessed better water dispersibility, which were beneficial for the degradation of bromamine acid aqueous solution. The degradation characteristics, such as effects of supported nZVI dosage, initial concentration and initial pH value of the solution on the decolorization efficiency were also investigated. The results showed that in an acidic environment the supported nZVI with a dosage of 2 g/L showed high activity in the degradation of bromamine acid with an initial concentration of 1,000 mg/L, and the degree of decolorization could reach up to 98%.

Nanoscale zero-valent iron incorporated with nanomagnetic diatomite for catalytic degradation of methylene blue in heterogeneous Fenton system

2016 ◽  
Vol 73 (11) ◽  
pp. 2815-2823 ◽  
Author(s):  
Yiming Zha ◽  
Ziqing Zhou ◽  
Haibo He ◽  
Tianlin Wang ◽  
Liqiang Luo
Keyword(s):  
Methylene Blue ◽  
Chemical Reduction ◽  
Nitrogen Adsorption ◽  
Catalytic Degradation ◽  
Zero Valent Iron ◽  
Precipitation Method ◽  
Heterogeneous Fenton ◽  
Nanoscale Zero Valent Iron ◽  
Co Precipitation ◽  
Fenton System

Nanoscale zero-valent iron (nZVI) incorporated with nanomagnetic diatomite (DE) composite material was prepared for catalytic degradation of methylene blue (MB) in heterogeneous Fenton system. The material was constructed by two facile steps: Fe3O4 magnetic nanoparticles were supported on DE by chemical co-precipitation method, after which nZVI was incorporated into magnetic DE by liquid-phase chemical reduction strategy. The as-prepared catalyst was characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, magnetic properties measurement and nitrogen adsorption–desorption isotherm measurement. The novel nZVI@Fe3O4-diatomite nanocomposites showed a distinct catalytic activity and a desirable effect for degradation of MB. MB could be completely decolorized within 8 min and the removal efficiency of total organic carbon could reach to 90% after reaction for 1 h.

scholarly journals INVESTIGATION OF REMOVAL OF HEXAVALENT CHROMIUM AND DIVALENT COBALT FROM AQUEOUS SOLUTIONS BY ORGANO-MONTMORILLONITE SUPPORTED IRON NANOPARTICLES

2016 ◽  
Vol 5 ◽  
pp. 81-88 ◽  
Author(s):  
Viktoriia Prus ◽  
Nataliya Zhdanyuk
Keyword(s):  
Environmental Remediation ◽  
Iron Nanoparticles ◽  
Removal Rate ◽  
Environmental Pollutants ◽  
Zero Valent Iron ◽  
Hexadecyltrimethylammonium Bromide ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nanoscale Zero Valent Iron ◽  
Supported Iron

A new class of nanoscale zero-valent iron particles supported on natural montmorillonite and organo-montmorillonite were synthesized and the feasibility for the removal of and was examined through laboratory batch test. The X – ray diffraction (XRD) and Fourier Transform Infrared spectrum (FTIR) investigation has been applied for determination of the particle size and mechanism of remediation process. The aim of this study was to enhance the reduction of persistent environmental pollutants difficult to degrade by immobilization of nanoscale zero-valent iron on an organo-montmorillonite. Batch experiments indicated that the reduction of both and was much greater with organo-montmorillonite supported iron nanoparticles reaching removal rate up to 98.5% and 95.6% respectively at the initial metal concentrations of 50 mg/L. Iron and crystalline iron oxide were detected by X-ray diffraction patterns. In the FTIR spectrum, CH2 groups were found in iron nanoparticles supported on hexadecyltrimethylammonium bromide modified montmorillonite (HDTMA-Mont/nZVI) particles but were significantly weakened in comparison with the spectrum of hexadecyl trimethylammonium bromide (HDTMA). Other factor that affects the efficiency of heavy metals removal such as pH values was also investigated. The obtained data and review of the current literature have given the opportunity to figure out the mechanisms of and removal which may thus promote the industrial application of nZVI technique in environmental remediation by changing the hydrophilic – hydrophobic properties of source systems.

scholarly journals Nanoscale zero-valent iron loaded vermiform expanded graphite for the removal of Cr (VI) from aqueous solution

2021 ◽  
Vol 8 (8) ◽  
pp. 210801
Author(s):  
Xinwei Cai ◽  
Yangshuai Qiu ◽  
Yanhong Zhou ◽  
Xuan Jiao
Keyword(s):  
Aqueous Solution ◽  
Environmental Remediation ◽  
Chemical Reduction ◽  
Physical Adsorption ◽  
Exothermic Reaction ◽  
Expanded Graphite ◽  
Living Environment ◽  
Zero Valent Iron ◽  
Total Chromium ◽  
Nanoscale Zero Valent Iron

Cr (VI) is indispensable in industrial manufacturing, and its extensive use leads to severe heavy-metal pollution in the water environment around people, posing a great danger to physical health and living environment of multitudinous organisms. Expanded graphite (EG) is considered as a typical material for adsorption, while nanoscale zero-valent iron (nZVI) can be applied to degrade and sedimentate various organic or inorganic pollutants. In this study, a simultaneous collaboration of EG and nZVI is carried out, with the investigation on the influence of different test conditions for adsorption performances. These findings demonstrate that nZVI@EG manifests favourable adsorptive performance on the removal of hexavalent chromium efficiently. nZVI, acting as an electron donor, is supposed to reduce Cr (VI) to Cr (III), turning itself into iron oxide or hydroxide. The whole process is an exothermic reaction, accompanying chemical reduction and physical adsorption. And Cr (III) is fastened on the appearance by deposition of chromium hydroxide or ferrochromium complex precipitation, which greatly reduces the total chromium content in the aqueous solution. Herein, as a new composite adsorbent, nZVI@EG shows promising prospects of practical applications in water contamination and environmental remediation.

scholarly journals Removal of aqueous organic pollutant by photo-Fenton process using low-cost Fe3O4/zeolite A

2021 ◽  
Vol 947 (1) ◽  
pp. 012013
Author(s):  
Ho Gia Quynh ◽  
Nguyen Anh Kiet ◽  
Huynh Van Thanh ◽  
Ta Man Tue ◽  
Nguyen Thi Truc Phuong ◽  
...  
Keyword(s):  
Textile Industry ◽  
Fenton Reaction ◽  
Low Cost ◽  
Organic Pollutant ◽  
Impregnation Method ◽  
Zeolite A ◽  
X Ray Diffraction ◽  
Initial Concentration ◽  
The Stability ◽  
Uv Lamps

Abstract Degradation of methylene blue (MB) in textile water treatment was investigated by using the photo - Fenton method (mixture of Fe2+ and H2O2 with the UV irradiation) in the presence of nano-sized and low-cost catalyst Fe3O4/Zeolite A. This catalyst was synthesized by impregnation method; furthermore, its photo – catalytic performances and durability in heterogeneous Fenton system were evaluated. Both the structure and the physical chemistry properties of the photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM). The study investigated the influences of different parameters of the MB decolorization efficiency such as initial concentration of peroxide attending the Fenton reaction, amounts of catalyst, pH of the dye solution and comparison of utilization of H2O2 in two cases with and without UV lamps. Under the optimum conditions which is the initial concentration of MB is 50 ppm and pH of dye solution is 3, high efficiencies of degradation were achieved – performance of 92.49%. These results suggest that the low-cost nanostructure catalyst Fe3O4/Zeolite A may be the considerable option because of the durability and the stability in the photo – Fenton reaction for organic wastewater treatment in textile industry.

scholarly journals Effectiveness of nanoscale zero-valent iron for the immobilization of Cu and/or Ni in water and soil samples

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
M. Gil-Díaz ◽  
M. A. Álvarez ◽  
J. Alonso ◽  
M. C. Lobo
Keyword(s):  
Water Samples ◽  
Soil Samples ◽  
Zero Valent Iron ◽  
Acidic Soil ◽  
Experimental Conditions ◽  
Relevant Effect ◽  
Physico Chemical ◽  
Nanoscale Zero Valent Iron ◽  
Water And Soil Samples ◽  
Dose Dependent Increase

Abstract In the last few years, the effectiveness of nanoscale zero-valent iron (nZVI) as a treatment for polluted waters and soils has been widely studied. However, little data are available on its efficacy for metal immobilization at low and moderate doses. In this study, the effectiveness of two doses of commercial nZVI (1 and 5%) to immobilize Cu and/or Ni in water and acidic soil samples was evaluated. The influence of the nanoremediation technology on iron availability, physico-chemical soil properties and soil phytotoxicity was also assessed. The results show that the effectiveness of nZVI to immobilize Cu and Ni in water and soil samples was determined by the dose of the nanomaterial and the presence of both metals. Nickel immobilization was significantly decreased by the presence of Cu but the opposite effect was not observed. nZVI showed better immobilization capacity in water than in soil samples. In water, the dose of 5% completely removed both metals, whereas at a lower dose (1%) the percentage of immobilized metal decreased, especially for Ni in Cu + Ni samples. In soil samples, 5% nZVI was more effective in immobilizing Ni than Cu, with a 54% and 21% reduction of leachability, respectively, in single contaminated samples. In Cu + Ni soil samples, nZVI treatment led to a significant decrease in Ni immobilization, similar to that observed in water samples. The application of nZVI induced a dose-dependent increase in available Fe—a relevant effect in the context of soil rehabilitation. Germination assays of Medicago sativa and Vicia sativa seeds revealed that treatment with nZVI did not induce phytotoxicity under the experimental conditions tested, and that the phytotoxicity induced by Ni decreased significantly after the treatment. Thus, the use of nZVI emerges as an interesting option for Cu and/or Ni immobilization in water samples. The effectiveness of nZVI to remove Cu from acidic soil samples was moderate, while for Ni it was strongly dependent on the presence of Cu. These observations therefore indicate that the results in water samples cannot be extrapolated to soil samples.

Sign in / Sign up

Export Citation Format

Share Document