Enhanced Removal of Mercury and Lead by a Novel and Efficient Surface-functionalized Imogolite with Nanoscale Zero-valent Iron Material

2021 ◽  
Author(s):  
Estefanía Martinis ◽  
Juliano Denardin ◽  
Raul Calderón Raul Calderón ◽  
Cristóbal Flores ◽  
Karen Manquián-Cerda ◽  
...  
Keyword(s):  
Multicomponent System ◽  
Kinetic Studies ◽  
Zero Valent Iron ◽  
Hybrid Nanomaterial ◽  
Adsorption Sites ◽  
Transmission Electron ◽  
Nanoscale Zero Valent Iron ◽  
Equilibrium Data ◽  
Softness Parameter ◽  
Chemical Procedure

Abstract A novel hybrid nanomaterial, nanoscale zero-valent iron (nZVI)-grafted imogolite nanotubes (Imo), was synthesized via a fast and straightforward chemical procedure. The as-obtained nanomaterial (Imo-nZVI) was characterized using transmission electron microscopy (TEM), electrophoretic mobility (EM) and vibrating sample magnetometry (VSM). The prepared Imo-nZVI was superparamagnetic at room temperature and could be easily separated by an external magnetic field. Sorption batch experiments were performed in single- and multicomponent system and showed that Hg2+ and Pb2+ could be quantitatively adsorbed at pH 4.0 with maximum adsorption capacities of 62.3 and 73.8 mg·g− 1, respectively. It was observed that the functional groups in Imo-nZVI interact preferentially with analytes according to Misono Softness parameter. The higher performance of Imo-nZVI compared with Imo and nZVI is related to the increased adsorption sites in the functionalized nanomaterial. The sorption equilibrium data obeyed the Langmuir model, while kinetic studies demonstrated that the sorption processes of Hg2+ and Pb2+ followed the pseudo-second-order model. This study suggests that the Imo-nZVI composite can be used as a promising sorbent and provides a simple and fast separation method for the removal of Hg and Pb ions from contaminated water.

Improvement of As(III) removal with diatomite overlay nanoscale zero-valent iron (nZVI-D): adsorption isotherm and adsorption kinetic studies

2016 ◽  
Vol 17 (1) ◽  
pp. 212-220 ◽  
Author(s):  
Nusavadee Pojananukij ◽  
Kitirote Wantala ◽  
Sutasinee Neramittagapong ◽  
Chitsan Lin ◽  
Duangkanok Tanangteerpong ◽  
...  
Keyword(s):  
Adsorption Isotherm ◽  
Kinetic Studies ◽  
Second Order ◽  
Zero Valent Iron ◽  
Order Kinetic ◽  
Kinetic Adsorption ◽  
Nanoscale Zero Valent Iron ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Nanoscale zero-valent iron coated on diatomite (nZVI-D) was successfully synthesized as a composite material. It is the combination of nZVI and diatomite which has been proved to be a promising material in arsenite or As(III) removal. The result showed that 25.5% of As(III) was removed using diatomite only but more than 95% of As(III) was removed using nZVI-D, at the same contact time of 60 min and pH 6. The experimental isotherm data for As(III) adsorption at different initial concentrations were analyzed using the Langmuir, Freundlich, and Dubinin–Radushkevich equations. Among these three, the equilibrium data fitted well with the Langmuir isotherm. The kinetic adsorption was also studied using the pseudo-first, second-order, and intraparticle diffusion equations. The data were well explained by the pseudo-second-order kinetic model. From the results of kinetic adsorption and the adsorption isotherm, it can be concluded that arsenite adsorption was controlled by the mass transfer and adsorption process.

Adsorption and advanced oxidation of diverse pharmaceuticals and personal care products (PPCPs) from water using highly efficient rGO–nZVI nanohybrids

2020 ◽  
Vol 6 (8) ◽  
pp. 2223-2238 ◽  
Author(s):  
Arvid Masud ◽  
Nita G. Chavez Soria ◽  
Diana S. Aga ◽  
Nirupam Aich
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Personal Care Products ◽  
Advanced Oxidation ◽  
Zero Valent Iron ◽  
Redox Activity ◽  
Personal Care ◽  
Adsorption Sites ◽  
Reduced Graphene ◽  
Nanoscale Zero Valent Iron

Reduced graphene oxide-nanoscale zero valent iron (rGO–nZVI) nanohybrid, with tunable adsorption sites of rGO and unique catalytic redox activity of nZVI, perform enhanced removal of diverse PPCPs from water.

A Facile Strategy to Fabricate Nanoscale Zero-Valent Iron Decorated Graphene Oxide Composite for Dechloridation of Trichloroacetic Acid in Water

2018 ◽  
Vol 18 (12) ◽  
pp. 8252-8257 ◽  
Author(s):  
Huixuan Zhang ◽  
Xinyi Zhang ◽  
Ruonan Guo ◽  
Qingfeng Cheng ◽  
Xiuwen Cheng
Keyword(s):  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
Sewage Treatment ◽  
Reduction Process ◽  
Zero Valent Iron ◽  
Chlorinated Organic Compounds ◽  
X Ray ◽  
Transmission Electron ◽  
Nanoscale Zero Valent Iron ◽  
Adsorption Desorption

In this study, nanoscale zero-valent iron decorated graphene oxide (NZVI/GO) composite was fabricated through a reduction process in the presence of sodium borohydride (NaBH4) solution. Subsequently, physicochemical properties of the NZVI/GO composites were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), N2 adsorption/desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transformation infrared spectroscopy (FT-IR) and Raman spectra. Results indicated that Fe species existed in the form of Fe0, which uniformly dispersed on the surface of GO. Furthermore, the performance of NZVI/GO was evaluated by the degradation of tichloroacetic acid (TCAA). TCAA can be rapidly degraded by NZVI/GO. This paper provides a promising strategy to synthesize versatile catalyst which would be potentially applied in sewage treatment to degrade chlorinated organic compounds.

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%.

Fine structural features of nanoscale zero-valent iron characterized by spherical aberration corrected scanning transmission electron microscopy (Cs-STEM)

The Analyst ◽  
2014 ◽  
Vol 139 (18) ◽  
pp. 4512-4518 ◽  
Author(s):  
Airong Liu ◽  
Wei-xian Zhang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Spherical Aberration ◽  
Zero Valent Iron ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Nanoscale Zero Valent Iron ◽  
Scanning Transmission ◽  
Aberration Corrected

An angstrom-resolution physical model of nanoscale zero- valent iron (nZVI) is generated with a combination of spherical aberration corrected scanning transmission electron microscopy (Cs-STEM) and energy-dispersive X-ray spectroscopy (EDS).

scholarly journals Surface coating with Ca(OH)2 for improvement of the transport of nanoscale zero-valent iron (nZVI) in porous media

2013 ◽  
Vol 68 (10) ◽  
pp. 2287-2293 ◽  
Author(s):  
Cai-jie Wei ◽  
Xiao-yan Li
Keyword(s):  
Porous Media ◽  
Surface Coating ◽  
Coating Layer ◽  
Zero Valent Iron ◽  
Mass Ratio ◽  
Batch Experiments ◽  
Effective Protection ◽  
Transmission Electron ◽  
Nanoscale Zero Valent Iron ◽  
Protection Layer

A novel thermal deposition method was developed to coat Ca(OH)2 on the surface of nanoscale zero-valent iron (nZVI). The nZVI particles with the Ca(OH)2 coating layer, nZVI/Ca(OH)2, had a clear core-shell structure based on the transmission electron microscopy observations, and the Ca(OH)2 shell was identified as an amorphous phase. The Ca(OH)2 coating shell would not only function as an effective protection layer for nZVI but also improve the mobility of nZVI in porous media for its use in environmental decontamination. A 10% Ca/Fe mass ratio was found to result in a proper thickness of the Ca(OH)2 shell on the nZVI surface. Based on the filtration tests in sand columns, the Ca(OH)2-based surface coating could greatly improve the mobility and transport of nZVI particles in porous media. In addition, batch experiments were conducted to evaluate the reactivity of Ca(OH)2-coated nZVI particles for the reduction of Cr(VI) and its removal from water.

scholarly journals REMOVAL OF TETRACYCLINE FROM AQUEOUS SOLUTIONS USING NANOSCALE ZERO VALENT IRON AND FUNCTIONAL PUMICE MODIFIED NANOSCALE ZERO VALENT IRON

2017 ◽  
Vol 25 (3) ◽  
pp. 223-233 ◽  
Author(s):  
Ulker Asli GULER
Keyword(s):  
Aqueous Solutions ◽  
Reduction Process ◽  
Zero Valent Iron ◽  
Maximum Adsorption Capacity ◽  
Mass Ratio ◽  
Order Model ◽  
First Order ◽  
Nanoscale Zero Valent Iron ◽  
Equilibrium Data ◽  
Pseudo Second Order

Nanoscale zero valent iron (nzvi) and functional pumice modified nanoscale zero valent iron (P-nzvi) were successfully synthesized and used for the removal of tetracycline (TC). These materials were characterized by SEM, TEM, XRD, FTIR, BET. Different factors such as the mass ratio, dosage of adsorbent, ph, initial TC concentration and temperature were investigated. Based on these results; a possible removal mechanism was proposed including TC adsorption and TC reduction via oxidation of Fe0 to Fe3+. In addition, isotherm and thermodynamic parameters were applied to the equilibrium data. The maximum adsorption capacity of TC by nzvi and P-nzvi was 105.46 mg/g and 115.13 mg/g, respectively. Adsorption and reduction kinetics were examined for the TC removal process. The pseudo-second-order model and pseudo-first-order model was observed for adsorption and reduction process, respectively. Finally, more than 90% of TC from aqueous solutions was removed by nzvi and P-nzvi.

scholarly journals Re-recognizing micro locations of nanoscale zero-valent iron in biochar using C-TEM technique

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kun Yang ◽  
Jialu Xu ◽  
Ming Zhang ◽  
Daohui Lin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Zero Valent Iron ◽  
Iron Hydroxides ◽  
Cross Sectional ◽  
Reducing Ability ◽  
Transmission Electron ◽  
Nanoscale Zero Valent Iron ◽  
Scanning Electron

AbstractBiochar supported nanoscale zero-valent iron (NZVI/BC), prepared commonly by liquid reduction using sodium borohydride (NaBH4), exhibits better reduction performance for contaminants than bare NZVI. The better reducing ability was attributed to attachment of nanoscale zero-valent iron (NZVI) on biochar (BC) surface or into the interior pores of BC particles due to observations by scanning electron microscopy (SEM) and plan transmission electron microscopy (P-TEM) techniques in previous studies. In this study, cross-sectional TEM (C-TEM) technique was employed firstly to explore location of NZVI in NZVI/BC. It was observed that NZVI is isolated from BC particles, but not located on the surface or in the interior pores of BC particles. This observation was also supported by negligible adsorption and precipitation of Fe2+/Fe3+ and iron hydroxides on BC surface or into interior pores of BC particles respectively. Precipitation of Fe2+ and Fe3+, rather than adsorption, is responsible for the removal of Fe2+ and Fe3+ by BC. Moreover, precipitates of iron hydroxides cannot be reduced to NZVI by NaBH4. In addition to SEM or P-TEM, therefore, C-TEM is a potential technique to characterize the interior morphology of NZVI/BC for better understanding the improved reduction performance of contaminants by NZVI/BC than bare NZVI.

scholarly journals Kinetic Studies of Nanoscale Zero-Valent Iron and Geobacter lovleyi for Trichloroethylene Dechlorination

2012 ◽  
Vol 17 (1) ◽  
pp. 33-41
Author(s):  
Young-Ju Kim ◽  
Sang-Woo An ◽  
Jun-Won Jang ◽  
In-Hwan Yeo ◽  
Han-Suk Kim ◽  
...  
Keyword(s):  
Kinetic Studies ◽  
Zero Valent Iron ◽  
Nanoscale Zero Valent Iron

scholarly journals Simultaneous adsorption and reduction of hexavalent chromium on biochar-supported nanoscale zero-valent iron (nZVI) in aqueous solution

2020 ◽  
Vol 82 (7) ◽  
pp. 1339-1349
Author(s):  
Fengfeng Ma ◽  
Bakunzibake Philippe ◽  
Baowei Zhao ◽  
Jingru Diao ◽  
Jian Li
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Zero Valent Iron ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Transmission Electron ◽  
Nanoscale Zero Valent Iron ◽  
Pseudo Second Order

Abstract Flax straw biochar (FSBC)-supported nanoscale zero-valent iron (nZVI) composite (nZVI-FSBC) combining the advantages of nZVI and biochar was synthesized and tested for Cr(VI) removal efficiency from aqueous solution. Surface morphology and structure of FSBC and nZVI-FSBC were characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller techniques, which help to clarify the mechanism of Cr(VI) removal from aqueous solution. The adsorption of Cr(VI) onto FSBC and nZVI-FSBC was best described by the pseudo-second-order and the Sips model. Compared with FSBC, nZVI-FSBC remarkably improved the performance in removing Cr(VI) under identical experimental conditions. Due to the collaborative effect of adsorption and reduction of nZVI-FSBC, the adsorption capacity of nZVI-FSBC for Cr(VI) is up to 186.99 mg/g. The results obtained by XPS, XRD, and FTIR confirmed that adsorption and reduction dominated the processes of Cr(VI) removal by nZVI-FSBC. As a supporter, FSBC not only improved the dispersion of nZVI, but also undertook the adsorption task of Cr(VI) removal. The surface oxygen-containing functional groups of nZVI-FSBC mainly participated in the adsorption part, and the nZVI promoted the Cr(VI) removal through the redox reactions. These observations indicated that the nZVI-FSBC can be considered as potential adsorbents to remove Cr(VI) for environment remediation.

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