Cooperative Research Center for Contamination Assessment and Remediation of Environments

Mawson Lakes, Australia

Cooperative Research Center for Contamination Assessment and Remediation of Environments

Mawson Lakes, Australia

Time filter

Source Type

Wang T.,Fujian Normal University | Jin X.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Science of the Total Environment | Year: 2014

Iron nanoparticles were firstly synthesized through a one-step room-temperature biosynthetic route using eucalyptus leaf extracts (EL-Fe NPs). Scanning electron microscopy (SEM) and X-ray energy-dispersive spectrometer (EDS) confirmed the successful synthesis of the spheroidal iron nanoparticles. Furthermore, X-ray diffraction (XRD) and Fourier Transform Infrared spectrometer (FTIR) indicated that some polyphenols are bound to the surfaces of EL-Fe NPs as a capping/stabilizing agent. Reactivity of EL-Fe NPs was evaluated for the treatment of swine wastewater and results indicated that 71.7% of total N and 84.5% of COD were removed, respectively. This demonstrated the tremendous potential of EL-Fe NPs for in situ remediation of eutrophic wastewater. © 2013 Elsevier B.V.


Lin Y.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | Chen Z.,Cooperative Research Center for Contamination Assessment and Remediation of Environments | And 4 more authors.
Applied Clay Science | Year: 2014

In this study, bentonite (Bent)-supported nanoscale zero-valent iron (Fe0) (Fe0Bent) was prepared to remove acid violet red B from an aqueous solution. Scanning electron microscopy (SEM) images of Fe0Bent and batch experiments indicated that the presence of bentonite decreased aggregation of iron nanoparticles and increased their reactivity. After reacting for 9min, Fe0Bent removed 95.6% of acid violet red B with a concentration of 800mg/l compared to Fe0, which removed 75.1%. Iron oxide and hydroxide were the reaction products of the reaction of Fe0Bent with acid violet red B. UV-vis spectra showed that the absorption peak of acid violet red B was degraded due to the break of azo linkages. Kinetic studies showed that the degradation rate suited the pseudo-first-order model well. The apparent activation energy was 40.86kJ/mol, which is typical of a chemically controlled reaction on the smectite surface. The Fe0Bent used to remove acid violet red B has the potential to be used for in situ remediation. © 2014 Elsevier B.V.


Su J.,Fujian Normal University | Lin S.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Desalination | Year: 2011

To increase the dispersion of nanoparticles and enhance their reactivity, bentonite-supported Fe/Pd nanoparticles (B/Fe/Pd) were synthesized and used for the dechlorination of P-chlorophenol (p-CP) from aqueous solution. The B/Fe/Pd was characterized with a scanning electron microscope (SEM), X-ray energy-dispersive spectrometer (EDS), X-ray diffraction (XRD), and specific surface area (BET). The results showed that the presence of bentonite led to a decrease in aggregation of Fe/Pd nanoparticles and enhanced their reactivity. More specifically, B/Fe/Pd indicated the highest p-CP dechlorination of 100%, while only 25.0% and 15.0% were obtained using B/Fe and bentonite (the conditions: C0=5.0mg/L and dose: 10.0g/L), respectively. In addition, kinetic studies show that the dechlorination rate of p-CP was described by pseudo first-order reaction kinetics, and the dechlorination rate increased with rising temperature and Pd loading. The apparent activation energy for dechlorination p-CP using B/Fe/Pd was 40.1kJ/mol, which is characteristic of a chemically surface-controlled reaction. Finally, a potential mechanism for degradation of p-CP is proposed, which is based on Fe acting as the reducing agent, while Pd acts as a catalyst with hydrogen generated from water and bentonite as a support. © 2011 Elsevier B.V.


Huang L.,Fujian Normal University | Weng X.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

Iron nanoparticles (Fe NPs) are often synthesized using sodium borohydride with aggregation, which is a high cost process and environmentally toxic. To address these issues, Fe NPs were synthesized using green methods based on tea extracts, including green, oolong and black teas. The best method for degrading malachite green (MG) was Fe NPs synthesized by green tea extracts because it contains a high concentration of caffeine/polyphenols which act as both reducing and capping agents in the synthesis of Fe NPs. These characteristics were confirmed by a scanning electron microscope (SEM), UV-visible (UV-vis) and specific surface area (BET). To understand the formation of Fe NPs using various tea extracts, the synthesized Fe NPs were characterized by SEM, X-ray energy-dispersive spectrometer (EDS), and X-ray diffraction (XRD). What emerged were different sizes and concentrations of Fe NPs being synthesized by tea extracts, leading to various degradations of MG. Furthermore, kinetics for the degradation of MG using these Fe NPs fitted well to the pseudo first-order reaction kinetics model with more than 20 kJ/mol activation energy, suggesting a chemically diffusion-controlled reaction. The degradation mechanism using these Fe NPs included adsorption of MG to Fe NPs, oxidation of iron, and cleaving the bond that was connected to the benzene ring. © 2014 Elsevier B.V. All rights reserved.


Huang L.,Fujian Normal University | Weng X.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

Iron-based nanoparticles (OT-FeNP) were synthesized using oolong tea extracts. Their morphology, structure and size were confirmed by scanning electron microscopy (SEM), X-ray energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), UV-visible (UV-vis) and Fourier Transform Infrared spectroscopy (FTIR). Formation of FeNP results in mostly spherical particles with diameters ranging from 40 to 50 nm. Degradation of malachite green (MG) using OT-FeNP demonstrated that kinetics fitted well to the pseudo first-order reaction by removing 75.5% of MG (50 mg/L). This indicated that OT-FeNP has the potential to serve as a green nanomaterial for environmental remediation. © 2013 Elsevier B.V. All rights reserved.


Zhang X.,Fujian Normal University | Lin S.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Water Research | Year: 2011

The use of nanoscale zero-valent iron (nZVI) to remediate contaminated groundwater is limited due to its lack of durability and mechanical strength. To address this issue, 20% (w/w) nZVI was loaded onto kaolinite as a support material (K-nZVI). More than 96% of Pb2+ was removed from aqueous solution using K-nZVI at an initial condition of 500 mg/L Pb2+ within 30 min under the conditions of 10 g/L of K-nZVI, pH 5.10 and a temperature of 30 °C. To understand the mechanism of removal of Pb2+, various techniques were implemented to characterize K-nZVI. Scanning electron microscopy (SEM) indicated that K-nZVI had a suitable dispersive state with a lower aggregation, where the mean specific surface area and average particle size as determined by the BET-N2 method and X-ray diffraction (XRD), were 26.11 m2/g and 44.3 nm, respectively. The results obtained from XRD, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) indicated that a small number of iron oxides formed on the surface of K-nZVI, suggesting that free Pb2+ was adsorbed onto K-nZVI and subsequently reduced to Pb0. © 2011 Elsevier Ltd.


Weng X.,Fujian Normal University | Huang L.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Industrial Crops and Products | Year: 2013

In this paper, green tea extract was used to synthesize iron nanoparticles (GT-Fe NPs) and degrade malachite green (MG) in aqueous solution. The results show that the damage to morphology and increase in size of GT-Fe NPs after reaction with MG were observed by SEM and EDS. XRD shows that there are few changes in the characteristic peaks of GT-Fe NPs before and after reaction. UV-vis spectroscopy shows that the absorption peak of MG decreased, while FTIR shows that the band at 1585cm-1 corresponded to the phenyl after reaction. The factors impacting on the removal efficiency of MG, including the initial solution pH, the initial concentration of MG, the dosage of GT-Fe NPs, and the reaction temperature, was also investigated. It emerged that 96% of MG was removed with a 50mg/L at 298K. Kinetics studies showed that the removal of MG fitted well to the pseudo first-order mode. © 2013 Elsevier B.V.


Liu Y.,Fujian Normal University | Gan L.,Fujian Normal University | Chen Z.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Journal of Hazardous Materials | Year: 2012

Paracoccus sp. strain YF1 immobilized on bamboo carbon was developed for the denitrification. The results show that denitrification was significantly improved using immobilized cells compared to that of free cells, where denitrification time decreased from 24. h (free cells) to 15. h (immobilized cells). The efficiency of denitrification increased from 4.57. mg/(L. h) (free cells) to 6.82. mg/(L. h) (immobilized cells). Kinetics studies suggest that denitrification by immobilized YF1 cells fitted well to the zero-order model. Scanning electron microscopy (SEM) demonstrated that firstly, the bacteria became stable on the inside and exterior of the bamboo carbon particles and secondly, they formed biofilm after adhesion. Various factors and their influences on biological denitrification were investigated, namely temperature, pH, initial nitrate concentrations and carbon sources. The immobilized cells exhibited more nitrate removal at various conditions compared to free cells since bamboo carbon as a carrier protects cells against changes in environmental conditions. Denitrification using the YF1 immobilized in bamboo carbon was also maintained 99.8% after the tenth cycle reuse, thus demonstrating excellent reusability. Finally, wastewater was treated using the immobilized cells and the outcome was that nitrogen was completely removed by bamboo-immobilized YF1. © 2012 Elsevier B.V.


Chen Z.,Fujian Normal University | Wang T.,Fujian Normal University | Jin X.,Fujian Normal University | Chen Z.,University of South Australia | And 5 more authors.
Journal of Colloid and Interface Science | Year: 2013

Kaolinite-supported nanoscale zero-valent iron (K-nZVI) was successfully synthesized as a multifunctional composite and used for the degradation of crystal violet (CV). The presence of kaolinite not only decreased the aggregation of zero-valent iron nanoparticles (nZVI) with maintenance of reactivity, but also facilitated reaction by increasing the local concentration of CV in the vicinity of nZVI as an adsorbent. This was confirmed by scanning electron microscopy (SEM) and batch experiments, which showed that 97.23% of CV was removed using K-nZVI, while only 78.72% and 39.22% of CV were removed using nZVI and kaolinite after 30min, respectively. Different factors impacting on degradation of CV were investigated as well. On the basis of these results, a removal mechanism was proposed including: (i) prompt adsorption of CV to the K-nZVI phase, and (ii) reduction of CV by Fe0 on K-nZVI. Furthermore, different adsorption and reduction kinetics were employed to examine the removal process of CV, where a better fit with the pseudo-second-order model for adsorption and pseudo-first-order model for reduction process was observed, and reduction was the rate limiting step. In addition, isotherm and thermodynamic parameters were evaluated for a specific study of the important adsorption step. Finally, the application of K-nZVI to treat wastewater showed the removal efficiency higher than 99.9%. © 2013 Elsevier Inc.


Wang Z.,University of South Australia | Wang Z.,Cooperative Research Center for Contamination Assessment and Remediation of Environments | Fang C.,University of South Australia | Fang C.,Cooperative Research Center for Contamination Assessment and Remediation of Environments | And 2 more authors.
ACS Sustainable Chemistry and Engineering | Year: 2014

In this paper, iron-polyphenol nanoparticles (Fe-P NPs) were synthesized using the extracts obtained from Australian native plant leaves, these being Eucalyptus tereticornis, Melaleuca nesophila, and Rosemarinus officinalis. The Fe-P NPs synthesized from the extracts were characterized using scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results show that the reaction between iron ions and polyphenols can form complex nanoparticles with sizes ranging from 50 to 80 nm, the surface of which presents organic characters. The synthesized nanoparticles were then utilized as a Fenton-like catalyst for decolorization of acid black 194 in solution. The batch experiments showed that 100% of acid black was decolorized, and over 87% total organic carbon (TOC) was removed. In addition, removal of acid black 194 fitted well to the pseudo-first-order model. Compared with the conventional Fenton reaction, the Fenton-like reaction with Fe-P NPs takes place more sustained and carefully within 200 min. Furthermore, it does not need to adjust pH for the reaction. © 2014 American Chemical Society.

Loading Cooperative Research Center for Contamination Assessment and Remediation of Environments collaborators
Loading Cooperative Research Center for Contamination Assessment and Remediation of Environments collaborators