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XRD patterns of (A) fresh, (B) Cu(II)-treated iron nanoparticles, and (C) Pb(II)-treated iron nanoparticles. Peaks are due to zero-valent iron (Fe), metallic copper (Cu), cuprite (Cu 2 O), magnetite/maghemite (Fe 3 O 4 /-Fe 2 O 3 ) (), and hematite (Fe 2 O 3 ) (). Peaks assigned to-PbO 2 are indicated by an open square symbol ().
Source publication
Effects of heavy metals on the dechlorination of carbon tetrachloride by iron nanoparticles were investi- gated in terms of reaction kinetics and product distribution using batch systems. Removal of heavy met- als and the interaction between heavy metals and iron nanoparticles at the iron surface were also exam- ined. It was found that Cu(II) enhan...
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... and lead at the surface of reacted iron nanoparticles. XRD analysis was further conducted to better under- stand the interaction between heavy metals and iron at the nanoparticle surface. The XRD analysis of fresh iron nanoparticles shows two major characteristic peaks at 44.8° and 65.2° degrees 2, indicating the presence of el- emental iron (Fig. 4A). A small amount of iron oxide (maghemite and/or magnetite) appeared in the fresh sam- ple. This could be attributed to a short exposure to air during the transport of fresh iron nanoparticles into a ves- sel before they were dried by nitrogen overnight. Figure 4B shows the XRD pattern for Cu(II)-treated iron nanoparticles taken after ...
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... could be attributed to a short exposure to air during the transport of fresh iron nanoparticles into a ves- sel before they were dried by nitrogen overnight. Figure 4B shows the XRD pattern for Cu(II)-treated iron nanoparticles taken after reacting with 250 mg/L Cu(II) for 12 h. Iron corrosion products (magnetite and/or maghemite) were found at the surface. ...
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... for making engineered bimetallic particles (e.g., Pd/Fe, Cu/Al, Ni/Fe) ( Grittini et al., 1995;Fennelly and Roberts, 1998;Kim and Carraway, 2000;Lien and Zhang, 2002). The formation of Cu 2 O could be attributed to the reac- (5) The XRD pattern for Pb(II)-treated iron nanoparticles taken after reacting with 250 mg/L Pb(II) for 24 h is shown in Fig. 4C. Iron corrosion products including hematite and magnetite and/or maghemite were detected. Theoretically, the reduction of Pb(II) to metallic lead should be thermodynamically favorable in the presence of zero-valent iron (E o rxn 0.32 V, Table 1). However, neither Pb 0 nor Pb(II) oxides (e.g., PbO, Pb(OH) 2 ) were identified in the ...
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... enhanced dechlorination of carbon tetrachloride by iron nanoparticles with Cu(II) can be attributed to the for- mation of bimetallic structure. The XRD analysis indicated metallic copper was deposited at the iron surface (Fig. 4b). The bimetallic structure leads a galvanic corrosion taking place readily at the surface to facilitate the electron trans- fer for the surface-mediated dechlorination of carbon tetra- chloride. Moreover, metallic copper is known as a mild hy- drogenation catalyst (Satterfield, 1991). It is effective for most of the elementary reactions ...
Citations
... The highest initial (at 0.5 h) removal efficiencies among the studied heavy metals were obtained for Cu and Pb. As the standard electrode potentials of Cu(II)/ Cu(0) and Pb(II)/Pb(0) are 0.34 and − 0.13 V, respectively, the reduction of these metal cations using nZVI is thermodynamically favourable (Lien et al., 2007). After 0.5 h of contact time, at nZVI doses of 0.25-2.0 ...
In this study, stabilised nano zero-valent iron (nZVI) was used to investigate the simultaneous removal of Cd(II), Cu(II), Pb(II), and Zn(II) from their aqueous solution over a 32-day period. The concentration of each metal used in the solution was 50 mg/L, and the applied nZVI doses were 0.25, 0.50, 1.0, and 2 g/L. The experiments were carried out using multi-metal solutions with initial pH values of 3 and 5. The results of the study showed that the overall metal removal efficiency followed the sequence: Pb > Cu > Zn > Cd. When 2.0 g/L of nZVI was applied to the multi-metal solutions, a high level of Pb(II) removal efficiency was achieved over a 32-day period, i.e. Pb(II) removal from the solutions with an initial pH of 3.0 and 5.0 was in the range 94.6–99.5% and 97.9–99.6%, respectively. Meanwhile, at the same dose of nZVI and both the initial solution pH values, high removal efficiencies of Cu (99.6–99.9%), Zn (62.8–82.2%), and Cd (52.2–67.1%) were achieved only over 2.5 h of contact time, and later substantially decreased. The initial pH of the multi-metal solutions did not have a considerable effect on the removal of metals at the initial contact time (0.5 h). However, the impact of pH on metal removal increased with an increase in contact time. Lower nZVI corrosion and therefore superior long-term treatment efficiency was achieved for solutions with an initial pH of 5 compared to that in solutions with an initial pH of 3.
... UV-visible spectra for various plant extract concentrations with Fe-Cu BNPs taken after adding the BNP solution, at different time intervals, clearly show the potential of Fe-Cu BNPs, as presented in Figure 5. With the passage of time, absorbance of DPPH solution decreases and after 30 min, the DPPH solution becomes colorless [40,41]. By increasing the concentration of BNPs, a sharp decrease in the absorbance of DPPH solution was observed. ...
Iron–copper bimetallic nanoparticles (Fe-Cu BNPs) were prepared via a green synthesis route. Ixora finlaysoniana has been used in this study as a capping and stabilizing agent in the modification of Fe-Cu BNPs. As-synthesized BNPs were characterized using different techniques including UV/Vis spectrophotometry, FTIR, XRD and SEM. A particle size analyzer and SEM studies indicated the particle size to be in the range of 50–200 nm. In addition, degradation of MB dye in an aqueous system and radical-scavenging potential in a DPPH assay were also examined using BNPs. Methylene blue dye degradation in 17 min was monitored with UV/Vis spectrophotometry, which exhibited the efficiency of Fe-Cu BNPs. Bimetallic nanoparticles were also found to be efficient in neutralizing DPPH free radicals. Furthermore, kinetic studies of both dye degradation and radical scavenging potential are reported in this article. Subsequently, Fe-Cu BNPs synthesized via a green and sustainable method can be employed for dye degradation and free radical-scavenging activities.
... UV-visible spectra for various plant extract concentrations with Fe-Cu BNPs taken after adding the BNP solution, at different time intervals, clearly show the potential of Fe-Cu BNPs, as presented in Figure 5. With the passage of time, absorbance of DPPH solution decreases and after 30 min, the DPPH solution becomes colorless [40,41]. By increasing the concentration of BNPs, a sharp decrease in the absorbance of DPPH solution was observed. ...
Citation: Younas, U.; Hassan, S.T.; Ali, F.; Hassan, F.; Saeed, Z.; Pervaiz, M.; Khan, S.; Jannat, F.T.; Bibi, S.; Sadiqa, A.; et al. Radical Scavenging and Catalytic Activity of Fe-Cu Bimetallic Nanoparticles Synthesized from Ixora finlaysoniana Extract. Coatings 2021, 11, 813. https://
... Lead Pb 2+ ions can be removed by adsorption of ions on the surface of nano zerovalent iron or reduction to the elemental lead form with nano zero-valent iron Li and Zhang 2007). In addition to the fact that lead reacts with nano zero-valent iron, it also precipitates in the form of lead Pb 2+ hydroxide and is oxidized to α-PbO 2 (Lien et al. 2007). Since the standard redox potential lead Pb 2+ /Pb 0 is more positive than the redox potential of Fe 2+ /Fe 0 , Pb 2+ can be reduced electrochemically to lead Pb 0 , at the same time the iron oxide content and pH of the solution increase during oxidation of iron Fe 0 to iron Fe 2+ and Fe 3+ ions, causing a larger amount of lead on the surface to transform into oxides and to hydrate the lead. ...
... Some metals, such as arsenic (As) and cromium (Cr), reduce the reactivity of nano zero-valent iron behaving as oxidizing agents or precipitated in the form of hydroxide or oxide on the surface of the nanoparticles, thus passivising them in this way. Other metals, such as copper (Cu) and nickel (Ni), increase the reactivity of nanomaterials by forming bimetallic particles in contact with nano zero-valent iron (Lien et al. 2007). ...
The total global production of refined copper in 2017 was approximately 19 million tons, with an annual growth rate of 3.4%. During the copper production process, a large proportion of the accompanying toxic metals end up in the environment. For this reason, there is a significant need for advanced wastewater treatment methods and technologies in order to ensure optimal water quality, eliminate heavy metals and other pollutants from water, and suggest appropriate industrial technology for the treatment of wastewater. Although various techniques for treatment of wastewater contaminated with heavy metals are being applied today, the choice of the most suitable wastewater treatment process depends on some basic commonly accepted parameters which will be discussed in this paper.
... Nickel Ni(II) and lead Pb(II) are the most common pollutants of electroplating industry, may be removed by ZVI-NP via reduction to Ni(0) and Pb(0) and by adsorption as Ni(II) and Pb(II) (Li and Zhang, 2007;Ponder et al., 2000), while reacting with ZVI-NP, Pb (II) also precipitates as Pb (OH) 2 and oxidizes as PbO 2 as confirmed by the XRD analysis (Ponder et al., 2000;Lien et al., 2007). Zhang et al. (2007) reported the synthesis and use of zero valent (ZV) bimetallic Ni/Fe nanoscale particles to dechlorinate p-chlorophenol (p-CP) in aqueous solution. ...
Today, polymers have become very crucial part of our daily life and they have been under intensive investigation in several disciplines including pharmacy, medicine, material sciences, and engineering. In particular, biopolymers, such as polysaccharides, proteins, and DNA, are fundamental to biological structure as well as function. In recent years, researchers and scientists have been interested in the removal of organic and inorganic contaminants from wastewater with the aid of nanocomposite hydrogels. Water contamination resulting from heavy metal ions and organic dyes is considered dangerous due to their high toxicity even at relatively low concentrations, non-biodegradation, and tendency of bioaccumulation. The increasing demand for the recovery of these metal ions and organic dyes from industrial effluents has elevated the development and the testing of advanced adsorbents. Classification of hydrogels and their responsiveness is discussed. This chapter provides the reader with a detailed introduction to the topic and recent developments in the area of nanocomposite hydrogels in separation science applications.
... Although application of PCP in agriculture has been banned for several decades, PCP is still detected in groundwater due to its long-term persistence [18]. Moreover, agricultural activities can occur in and around vanadium mining and smelting areas, leading to co-occurrence of vanadium and PCP in groundwater [19]. Biogeochemical fates of vanadium and PCP in the geological environment include potential mobilization and redox reactions, which have been studied independently [6,[20][21][22]. ...
Aquifer co-contamination by vanadium (V) and pentachlorophenol (PCP) involves complicated biogeochemical processes that remain poorly understood, particularly from the perspective of microbial metabolism. Batch experiment results demonstrated that V(V) and PCP could be competitively bio-reduced, with 96.0 ± 1.8% of V(V) and 43.4 ± 4.6% of PCP removed during 7 d operation. V(V) was bio-transformed to vanadium (IV), which could precipitate naturally under circumneutral conditions, facilitating the removal of up to 78.2 ± 3.1% dissolved total V. The PCP reductive dechlorination products were mainly 2,4,6-trichlorophenol and 4-monochlorophenol with lower toxicity. High-throughput 16S rRNA gene sequencing indicated that Pseudomonas, Soehngenia, and Anaerolinea might be responsible for the two bio-transformations, with detected functional genes of nirS and cprA. Extracellular reduction by cytochrome c and intracellular conversion by nicotinamide adenine dinucleotide (NADH) occurred for both V(V) and PCP. Extracellular proteins in microbial-secreted extracellular polymeric substances (EPS) might also be involved in these enzymatic bioprocesses. EPS could protect microbial cells through V(V) binding by the chemically reactive carboxyl (COO⁻), and hydroxyl (–OH) groups. These findings elucidate the metabolic processes during anaerobic V(V) and PCP biotransformation, advance understanding of their biogeochemical fates, and provide a foundation on which to develop novel strategies for remediation of co-contaminated aquifers.
... According to other researchers (Hu et al. 2010;Schrick et al. 2002), the reactivity of bimetallic nanoparticles is higher than that of iron nanoparticles. Such catalysts can be used to improve the efficiency of heavy metal immobilization, taking into account that the soil may be spiked with several heavy metals (Lien et al. 2007). Figure 1 shows the images of untreated and treated soil samples. ...
The present manuscript studies the effectiveness of commercial nano zero valent iron (nZVI) particles in decreasing the availability of Cd, Cu, Ni, and Pb in spiked soil samples and to remove the same heavy metals from aqueous solutions. The difference of nZVI efficiency between single and multi-metal contamination was evaluated. The application of nZVI in water samples showed higher effectiveness in the cases of single metal contamination. The effectiveness of single- and multi-metal (mixtures of Cu, Ni, Pb and Cd, Cu, Ni, Pb) immobilization in soil using different doses (0%, 0.85%, 1.7%, 2.55%, and 5.1%) of nZVI was determined. Immobilization efficiency was assessed using the leaching procedure and depended on a particular metal and the dose of nZVI. In all cases, it was determined that an increasing amount of nZVI resulted in decrease in the leaching of analysed metals. In cases, where higher nZVI doses were used, higher immobilization efficiency was observed for heavy metals in multi-metal contamination. The application of nZVI significantly reduced leaching of all heavy metals and this strategy can be successfully used for heavy metals stabilization in soils.
... However, by-product distribution study was not the aim of this work and by-products different from VOCs such as CH 4 , CO, CO 2 (Lien and Zhang, 1999;Choe et al., 2001;Song and Carraway, 2006), were not analyzed. CF (45e56%) and DCM (up to 0.3% of initial CT) were detected as by-products at pH 7 and 12, after 99% of CT degradation, similarly to what was reported previously (Helland et al., 1995;T amara and Butler, 2004;Song and Carraway, 2006;Lien et al., 2007;Feng et al., 2008), which confirms CT and CF hydrogenolysis. Isotopic mass balances showed a maximum Dd 13 C SUM (defined as final d 13 C SUM , Eq. S6, with respect to initial d 13 C SUM considering, CT and by-product CF data) of only þ1.5‰ at pH 7, compared to þ35‰ at pH 12. Thus, at pH 7, CF degradation to other by-product different from DCM was insignificant in the present experimental conditions and duration (3.5 h). ...
A dual element CCl isotopic study was performed for assessing chlorinated methanes (CMs) abiotic transformation reactions mediated by iron minerals and Fe(0) to further distinguish them in natural attenuation monitoring or when applying remediation strategies in polluted sites. Isotope fractionation was investigated during carbon tetrachloride (CT) and chloroform (CF) degradation in anoxic batch experiments with Fe(0), with FeCl2(aq), and with Fe-bearing minerals (magnetite, Mag and pyrite, Py) amended with FeCl2(aq), at two different pH values (7 and 12) representative of field and remediation conditions. At pH 7, only CT batches with Fe(0) and Py underwent degradation and CF accumulation evidenced hydrogenolysis. With Py, thiolytic reduction was revealed by CS2 yield and is a likely reason for different Λ value (Δδ13C/Δδ37Cl) comparing with Fe(0) experiments at pH 7 (2.9 ± 0.5 and 6.1 ± 0.5, respectively). At pH 12, all CT experiments showed degradation to CF, again with significant differences in Λ values between Fe(0) (5.8 ± 0.4) and Fe-bearing minerals (Mag, 2 ± 1, and Py, 3.7 ± 0.9), probably evidencing other parallel pathways (hydrolytic and thiolytic reduction). Variation of pH did not significantly affect the Λ values of CT degradation by Fe(0) nor Py. CF degradation by Fe(0) at pH 12 showed a Λ (8 ± 1) similar to that reported at pH 7 (8 ± 2), suggesting CF hydrogenolysis as the main reaction and that CF alkaline hydrolysis (13.0 ± 0.8) was negligible. Our data establish a base for discerning the predominant or combined pathways of CMs natural attenuation or for assessing the effectiveness of remediation strategies using recycled minerals or Fe(0).
... Previous research reported that commercial irons could effectively degrade CT (Tamara and Butler, 2004). In recent decade, nanoscale zerovalent iron (nZVI) has received huge attentions due to its large specific surface area and high reactivity (Nurmi et al., 2005;Lien et al., 2007). However, nZVI can also react with water or dissolved oxygen (DO), forming a passivated film which can hinder the further reactions between the reductant and contaminants (Xie and Cwiertny, 2010). ...
Sulfide-modified nanoscale zerovalent iron (S-nZVI) could potentially be efficient in the degradation of haloalkane contaminants due to its high reactivity. The efficiency of CCl4 (CT) degradation by S-nZVI was assessed under various conditions, including initial pH of solution, CT concentration, S-nZVI dosage, and ambient temperature. Results showed that reductive degradation of CT by SnZVI followed pseudo-first-order kinetics. The rate of CT degradation showed negative correlation to CT concentration, while higher initial solution pH in the range of 3 - 9, higher S-nZVI dosage, and higher ambient temperature stimulated CT degradation. Comparison among S-nZVI, nZVI, and FeS suggested that S-nZVI had the highest efficiency for CT degradation due to the unique surface structure and physicochemical property of S-nZVI.
... Nickel Ni(II) and lead Pb(II) are the most common pollutants of electroplating industry, may be removed by ZVI-NP via reduction to Ni(0) and Pb(0) and by adsorption as Ni(II) and Pb(II) (Li and Zhang, 2007;Ponder et al., 2000), while reacting with ZVI-NP, Pb (II) also precipitates as Pb (OH) 2 and oxidizes as PbO 2 as confirmed by the XRD analysis (Ponder et al., 2000;Lien et al., 2007). Zhang et al. (2007) reported the synthesis and use of zero valent (ZV) bimetallic Ni/Fe nanoscale particles to dechlorinate p-chlorophenol (p-CP) in aqueous solution. ...
Nanotechnology is the one of the most emerging field of applied science,
focused on the design, synthesis, characterization and application of
materials and devices on the nanoscale. Nanotechnology hold great potential
in the field of environmental protection by improving the environment, by
using materials to detect, prevent, and remove pollutants, as well as to design
cleaner industrial processes and create environmentally responsible
products.The present chapter deals with the brief reviews of the ongoing
research work and development activities on environmental water pollution
remediation by using nanomaterials. In this chapter, the essential aspects
of environmental problems are reviewed and then overview the availability
and practice of different surface modified nanomaterials (such as Iron
nanoparticles, bimetallic nanoparticles, CNT and natural polymer-silica
nanocomposites) for removal of heavy metals, metal ions, complex organic
compounds, natural organic matter, nitrate, and other pollutants present
in surface water, ground water, and/or industrial water. An attempt is
also being made to include some information like the optimise conditions
such as pH, required doses, initial concentrations, and treatment
performances of nanomaterials, so that complete information is available
to the readers.
