https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:35201 1 mM) apparently enhanced the degradation of Acid Orange 7 (AO7) independent of the presence of phosphate (PBS) buffer. Both PBS and chloride favored the degradation of AO7, while PBS played a more important role when they co-existed. The degradation efficiency of AO7 was enhanced by increasing the concentration of PBS and chloride. A maximum of absorbable organic halides (AOX) accumulation was observed; indicating some chlorinated byproducts could be initially generated and further oxidized by increasing the reaction time. It is demonstrated that the PBS/PMS system, with a lower AOX formation at the same chloride concentration, is superior to the Co/PMS system, a typical sulfate radical-based system. The active chlorine species (HClO/Cl₂) were found to be the dominant oxidants in the presence of higher chloride concentration ( > 50 mM) under neutral conditions. The findings of this work may promote the further application of PMS-based oxidation processes in saline effluents treatment.]]> Wed 26 Jun 2019 15:26:19 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48350 Wed 15 Mar 2023 09:56:49 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34459 PA/PMS) was nearly 4.4–15.9 fold higher than that in PMS/base system (k_PMS/base) without any polyphosphates. Increases in PA (or PB) concentration, PMS dose and pH favored the rapid dye degradation. Gas chromatograph-mass spectrometer (GC-MS) data confirmed AO7 and 2,4,6-trichlorophenol (2,4,6-TCP) were decomposed to a series of organic intermediates. The radical quenching and probe oxidation experiments indicate the degradation of organic compounds in the PA/PMS and PB/PMS processes was not reliant on sulfate radical (SO₄•−) and hydroxyl radical (•OH) species but on O₂•− and ¹O₂ reactive species. Comparison experiments show that the polyphosphate/PMS process was much more favorable than PDS/base process. The present work provides a novel way to activate PMS for contaminant removal using industrial polyphosphate wastewaters.]]> Wed 13 Mar 2019 13:19:26 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:35936 in-situ precipitation of CeO₂ nanoparticles (size: ~26 nm) on the surface of flower-like Bi₂MoO₆ superstructures (diameter: 2.1-3.5 µm) by a simple method. The as-prepared photocatalysts were systematically characterized by a range of techniques. The photocatalytic degradation of rhodamine B (RhB) dye, methyl orange (MO) dye and tetracycline (TC) antibiotic by this novel photocatalyst was investigated under visible-light irradiation. The CeO₂/Bi₂MoO₆ heterojunction with a CeO₂/Bi₂MoO₆ weight ratio of 0.05 (0.05Ce-Bi) exhibited the highest photocatalytic activity with the RhB degradation efficiency of 100% in 75 min, which was considerably higher than those of pristine CeO₂ (26.8%) and Bi₂MoO₆ (80.3%) as well as their physical mixtures (74.8%). The more efficient separation of electron-hole pairs was identified as the primary reason of the enhanced photocatalytic activity. Moreover, the synthesized material maintained satisfactory activity even after 6 recycling runs, indicating its high photocatalytic stability. Therefore, our finding offers a new avenue for development of stable and efficient heterojunction photocatalysts for environmental purification.]]> Wed 01 Jul 2020 10:18:43 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47409 Tue 17 Jan 2023 16:29:29 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43089 Tue 13 Sep 2022 12:26:39 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34058 2+/peroxymonosulfate (PMS) process was examined. Degradation efficiency, intermediate products, AOX (adsorbable organic halogen) formation and mineralization were considered. An overall negative impact was observed within the concentration of Cl⁻ up to 100 mM, differing from the dual effect of chloride on dye degradation process as previously observed. The presence of high levels of Cl⁻ led to a low production of AOX and a reduction of the formation of chlorinated by-products. The mineralization was also restrained when the Cl⁻ concentration was increased. Degradation pathways for these processes are proposed. These findings provide valuable information about the degradation pathways of dyes and about the formation mechanism of chlorinated by-products in industrial saline wastewater treatment.]]> Tue 05 Feb 2019 12:50:55 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34837 20 mM) apparently accelerated AO7 discoloration rate. The apparent effects of the two co-existing inorganic ions were determined by roles of the dominating ions at varied molar ratio of [NH₄⁺]/[Cl⁻]. The present study may have technical implications for the treatment of industrial wastewater containing diverse ions in practice.]]> Thu 16 May 2019 14:15:52 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34836 in situ growth of Ag₂O nanoparticles (size: ~12 nm) on their surfaces was realized by a simple deposition method. All Ag₂O/TaON heterojunctions were much more active than pristine TaON or a mechanical mixture of Ag₂O and TaON in the degradation of organic pollutants (cationic dye rhodamine B, anionic dye methyl orange and neutral para-chlorophenol) under visible light (λ > 400 nm). Significantly, the highest photocatalytic activity was observed in the heterojunction with a Ag/Ta molar ratio of 0.1/1 (0.1Ag-Ta). The RhB degradation rate constant using 0.1Ag-Ta is approximately 9.7 and 3.1 times higher than those obtained by using TaON microspheres, and the mechanical mixture, respectively. The superior photocatalytic performance of Ag₂O/TaON is ascribed to the hierarchical superstructure and efficient charge separation. The mainly involved active species (holes and superoxide radicals) were identified via radical trapping experiments and electron paramagnetic resonance spectroscopy. The results demonstrate that Ag₂O/TaON is a potential VLD photocatalyst for wastewater treatment.]]> Thu 16 May 2019 14:08:57 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34102 in-situ anchoring Ag₃VO₄ nanoparticles (size: ~21 nm) on the surface of Bi₂WO₆ microflowers (diameter: 2.5-4.5 µm) by a facile deposition route. The photocatalytic activity of these heterojunctions were studied by decomposing cationic dye rhodamine B (RhB), anionic dye methyl orange (MO) and neutral para-chlorophenol (4-CP) under visible light irradiation (λ > 400 nm). Among all the tested catalysts, the heterojunction with a Ag₃VO₄/Bi₂WO₆ molar ratio of 0.15/1 displays the maximum activity with the RhB degradation rate constant of up to 0.0392 min^-1, a 6.7 or 1.7 times more enhancement compared with the pure Bi₂WO₆ or Ag₃VO₄. It is found that the introduction of Ag₃VO₄ is in favor of suppressing the electron-hole pair recombination of Bi₂WO₆, leading to an enhanced photocatalytic activity with good stability. The photogenerated holes (h⁺) and superoxide radicals (O·₂¯) play critical roles during the photocatalytic process. Ag₃VO₄/Bi₂WO₆ will have great potential in applications for environmental remediation due to the facile preparation method and superior photocatalytic activity.]]> Thu 07 Feb 2019 14:26:20 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26956 IV) process can efficiently oxidize organic pollutants such as Acid Orange 7, even in the presence of chloride. Fluorescent probe technology suggests hydroxyl radicals were generated in UV/Ce(_IV) process, but not in UV/Ce(_IV)/Cl⁻ system. In the presence of chloride, Ce(_IV)-chloride complex was formed, which can directly oxidize dyes or generate reactive oxygen species by chlorine activation. Although degradation and mineralization rates of dyes were still inhibited to some extents by large amounts of chloride, but negligible AOX was generated. Therefore, UV/Ce(_IV) process can be recommended as an alternative AOPs when treating acidic saline wastewater.]]> Sat 24 Mar 2018 07:27:02 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30584 Sat 24 Mar 2018 07:23:59 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30586 Sat 24 Mar 2018 07:23:56 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32188 PMS. Increasing acidity and iron dosage favored a rapid degradation of AO7. The presence of chloride greatly inhibited dye removal in Fe⁰/H₂O₂ and Fe⁰/PS systems, whilst accelerated dye degradation was observed in the Fe⁰/PMS system. In contrast, mineralization of AO7 in the Fe⁰/PMS/Cl- system was minimal, because of formation of lots of refractory chlorinated phenols as identified by GC-MS. These findings are useful for selecting the most appropriate technology for textile wastewater treatment, depending on the wastewater constituents and pH.]]> Mon 23 Sep 2019 11:21:21 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47476 Mon 23 Jan 2023 11:26:30 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40433 Fri 29 Jul 2022 10:41:40 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45175 2+, Mn²⁺, Cu²⁺, H₂PO₄⁻ and SO₄²⁻) and organic acids (oxalic acid and citric acid). SEM and TEM analyses indicated that the MOF as a support efficiently prevent NZVI from aggregation for quick and effective removal of As(III). Through the non-linear least-squares (NLLS) adjustment, As(III) removal by MOF-NZVI could be well fitted by pseudo first and second order reaction kinetics, as well as the Freundlich isotherm. FTIR, XRD and XPS results verified that NZVI and iron oxyhydroxides (Fe₃O₄, γ-Fe₂O₃, γ-FeOOH and α-FeOOH) might be responsible for the effective removal of As(III) and its oxidized product As(V) with an adsorption capacity of 360.6 mg As per g NZVI through chemical oxidation and physical adsorption. This work indicates that MOF-NZVI with good reusability and high efficiency is promising for application in As(III)-polluted wastewater treatment.]]> Fri 28 Oct 2022 11:28:57 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29921 Fri 24 Aug 2018 09:00:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32193 Fri 20 Sep 2019 02:20:59 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:49389 Fri 12 May 2023 14:34:02 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32187 Fri 11 May 2018 13:24:24 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33161 Fri 07 Sep 2018 16:40:17 AEST ]]>