https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30779 2+ and Cu²⁺ on the oxidative degradation of Amoxicillin (AMX) by heterogeneous Fenton-like oxidation using nanoscale zero-valent iron (nZVI) as a catalyst was investigated. It was found that about 90.0% and 54.7% of AMX was degraded in the presence of 1 mM Cu²⁺ and 1 mM Mg²⁺ ions respectively, while 60.2% of AMX was removed by the control sample. Scanning electron microscopy (SEM) indicated that nZVI aggregated visibly after degradation of amoxicillin. X-ray photoelectron spectrometer (XPS) confirmed the reduction of Cu²⁺ to Cu⁰ by Fe⁰ on nZVI’s surface to form similar Fe/Cu bimetal to accelerate the degradation of AMX, and magnesium oxides or hydroxides formed on the surface of nZVI to restrain the removal of AMX. X-ray diffraction (XRD) demonstrated the existence of Fe⁰ in fresh nZVI and the corrosion aggregation of nZVI to form iron oxides or hydroxides after reaction. Kinetics studies demonstrated a pseudo first-order kinetics model for the oxidative degradation with the observed maximum K_obs as 0.0867 min⁻¹ in the presence of 1 mM Cu²⁺. The reason for this enhanced bimetallic catalytic activity is discussed.]]> Sat 24 Mar 2018 07:37:52 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:32675 Acinetobacter venetianus in 96 h, while the removal efficiency of chemical oxygen demand (COD) in the aqueous phase was only 56.8%, indicating that degraded metabolites existed in solution. To solve this problem, a Fenton-like system consisting of nanoscale zero-valent iron (nZVI) and hydrogen peroxide was used for further oxidation of the metabolites after biodegradation. Results showed that the total COD removal increased from 56.8% to 89% under the optimal condition. In addition, effects of initial pH (2.0–9.0), ZVI dosage (0–2.0 g L-1), hydrogen peroxide (H₂O₂) dosage concentration (0–15 mmol L-1) and temperature (298–308 K) on the treatment efficiency of the combined process were studied. Scanning electron microscopy (SEM) demonstrated that changes to the surface of nZVI occurred. GC-MS revealed that the degraded metabolites were mineralized practically by nZVI/H₂O₂ system. The results points towards the potential of Fenton-like oxidation as a short post-treatment after a biological process for the treatment of organic pollutants in wastewater.]]> Fri 17 Nov 2023 11:42:05 AEDT ]]>