Carbon zero-valent iron materials possessing high-content fine Fe0 nanoparticles with enhanced microelectrolysis-Fenton-like catalytic performance for water purification

Abstract This study primarily focused on how to effectively remove nitrate by catalytic denitrification through zero-valent iron (Fe0) and Pd-Ag catalyst. In order to get better catalytic performance, response surface methodology (RSM), instead of the single factor experiments and orthogonal tests, was firstly applied to optimize the condition parameters of the catalytic process. Results indicated that RSM is accurate and feasible for the condition optimization of catalytic denitrification. Better catalytic performance (71.6% N2 Selectivity) was obtained under the following conditions: 5.1 pH, 127 min reaction time, 3.2 mass ration (Pd: Ag), and 4.2 g/L Fe0, which was higher than the previous study designed by the single factor experiments (68.1%) and orthogonal tests (68.7%). However, under the optimal conditions, N2 selectivity showed a mild decrease (69.3%), when the real wastewater was used as the influent. Further study revealed that the cations (e.g., K+, Na+, Ca2+, Mg2+, and Al3+) and anions (e.g., Cl-, HCO3-, and SO42-) exist in wastewater may have distinctive influence on N2 selectivity. Finally, the reaction mechanism and kinetic model of catalytic denitrification were further studied.

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Preparation of Sepiolite Nanofibers Supported Zero Valent Iron Composite Material for Catalytic Removal of Tetracycline in Aqueous Solution

Frontiers in Chemistry ◽

10.3389/fchem.2021.736285 ◽

2021 ◽

Vol 9 ◽

Author(s):

Xiaoyu Han ◽

Hong Zhang ◽

Caihong Zhang ◽

Yan Zhao ◽

Na Zhang ◽

...

Keyword(s):

Removal Efficiency ◽

Active Sites ◽

Ph Value ◽

Catalytic Performance ◽

Aqueous System ◽

Zero Valent Iron ◽

High Catalytic Activity ◽

Catalyst Dosage ◽

Hcl Removal ◽

Sepiolite Nanofibers

The heavy use of antibiotics in medicine, stock farming and agriculture production has led to their gradual accumulation in environmental media, which poses a serious threat to ecological environment and human safety. As an efficient and promising catalyst for the degradation of antibiotics, nanoscale zero valent iron (nZVI) has attracted increasing attention in recent years. In this study, sepiolite nanofiber supported zero valent iron (nZVI/SEP) composite was prepared via a facile and environmentally friendly method. The nZVI particles (with size of 20–60 nm) were dispersed evenly on the surface of sepiolite nanofibers, and the catalytic performance for the removal of tetracycline hydrochloride (TC-HCl) in aqueous system was investigated. The effect of nZVI loading amount, catalyst dosage, H2O2 concentration and pH on the removal efficiency of TC-HCl were studied. It was revealed that the sepiolite supporter effectively inhibited the agglomeration of nZVI particles and increased the contact area between contaminant and the active sites, resulting in the higher catalytic performance than pure nZVI material. The TC-HCl removal efficiency of nZVI/SEP composite was up to 92.67% when TC-HCl concentration of 20 mg/L, catalyst dosage of 1.0 g/L, H2O2 concentration of 1.0 mM, pH value of 7. Therefore, the nZVI/SEP composites possess high catalytic activity for TC-HCl removal and have great application prospects in antibiotic wastewater treatment.

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Single-crystalline Fe7S8/Fe3O4 coated zero-valent iron synthesized with vacuum chemical vapor deposition technique: Enhanced reductive, oxidative and photocatalytic activity for water purification

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2020.123442 ◽

2021 ◽

Vol 401 ◽

pp. 123442

Author(s):

Hongyun Niu ◽

Yongliang Yang ◽

Weijia Zhao ◽

Hongzhou Lv ◽

Hui Zhang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Chemical Vapor Deposition ◽

Water Purification ◽

Vapor Deposition ◽

Chemical Vapor ◽

Zero Valent Iron ◽

Deposition Technique ◽

Single Crystalline ◽

Chemical Vapor Deposition Technique ◽

Vapor Deposition Technique

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Rapid point-of-use water purification using nanoscale zero valent iron (nZVI) particles

Chinese Science Bulletin ◽

10.1007/s11434-014-0440-1 ◽

2014 ◽

Vol 59 (29-30) ◽

pp. 3926-3934 ◽

Cited By ~ 2

Author(s):

Jing Li ◽

Qi Chen ◽

Xinyue Li ◽

Maosheng Yao

Keyword(s):

Water Purification ◽

Zero Valent Iron ◽

Point Of Use ◽

Nanoscale Zero Valent Iron

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Amino-functionalized MOFs with high physicochemical stability for efficient gas storage/separation, dye adsorption and catalytic performance

Journal of Materials Chemistry A ◽

10.1039/c8ta07839d ◽

2018 ◽

Vol 6 (47) ◽

pp. 24486-24495 ◽

Cited By ~ 39

Author(s):

Weidong Fan ◽

Xia Wang ◽

Ben Xu ◽

Yutong Wang ◽

Dandan Liu ◽

...

Keyword(s):

Water Purification ◽

Dye Adsorption ◽

Gas Storage ◽

Catalytic Performance ◽

Physicochemical Stability

Three versatile amino-functionalized InIII/AlIII/ZrIV-MOFs with high-physicochemical stability for gas storage/separation, water purification and catalysis.

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REMOVAL OF Cu(II), Cd(II), Co(II), Zn(II), Cr(VI) FROM WASTEWATER BY STABILIZED NANOSCALE ZERO-VALENT IRON

KPI Science News ◽

10.20535/kpisn.2021.1.217279 ◽

2021 ◽

Author(s):

Yurii M. Kholodko ◽

Antonina I. Bondarieva ◽

Viktoriia Yu. Tobilko ◽

Iryna A. Kovalchuk ◽

Borys Yu. Kornilovych

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Wastewater Treatment ◽

Phase Composition ◽

Metal Ions ◽

Water Purification ◽

Heavy Metal Ions ◽

Complex Mixture ◽

Zero Valent Iron ◽

Sorption Properties

Background. Obtaining sorption materials based on natural raw materials for water purification from pollution by heavy metal ions is an urgent task of our time. Composites with zero-valent iron nanoparticles immobilized on the surface of clay minerals show rather high sorption properties concerning ions of some heavy metals. However, there are only a few proceedings devoted to the physicochemical substantiation of wastewater treatment processes containing a complex mixture of such pollutants. Objective. The purpose of the paper is to study the physicochemical regularities of wastewater treatment from a mixture of ions of heavy metals Cu(II), Cd(II), Co(II), Zn(II), Cr(VI) using stabilized nano dispersed powders of zero-valent iron. Methods. The phase composition and structural-sorption characteristics of palygorskite and composites were studied by X-ray phase analysis and low-temperature adsorption-desorption of nitrogen. The efficiency of removal of metal ions by silicate materials was investigated using the sorption method. The equilibrium concentrations of each of the metals were determined by inductively coupled plasma atomic emission spectrometry. Results. We have investigated the physicochemical features of wastewater treatment containing a complex mixture of heavy metal ions (Cu(II), Cd(II), Zn(II), Co(II), Cr(VI)). The phase composition and structural-sorption properties of stabilized nano dispersed powders of zero-valent iron have been studied. It has been experimentally confirmed that the materials obtained have significantly better sorption properties for the removal of heavy metals from aqueous solutions in comparison with natural palygorskite. Using Freundlich and Langmuir equations sorption isotherms were calculated. Conclusions. It has been established that stabilized nano dispersed powders of zero-valent iron can be successfully used for the purification of wastewater containing a mixture of toxic ions Cu(II), Cd(II), Co(II), Zn(II) and Cr(VI). It is shown that the degree of water purification by the obtained sorbents is 3–5 times higher than that for the unmodified mineral. A significant increase in the values of sorption of anionic forms of Cr(VI), which are difficult to remove from polluted waters by natural ion exchangers, has been determined.

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