TY - JOUR A1 - Nadejde, C. A1 - Neamtu, M. A1 - Schneider, Rudolf A1 - Hodoroaba, Vasile-Dan A1 - Ababei, G. A1 - Panne, Ulrich T1 - Catalytical degradation of relevant pollutants from waters using magnetic nanocatalysts N2 - The catalytic efficiency of two magnetically responsive nanocatalysts was evaluated for the Degradation of Reactive Black 5 (RB5) and Reactive Yellow 84 (RY84) azo dyes using hydrogen peroxide as oxidant undervery mild conditions (atmospheric pressure, room temperature). In order to obtain the nanocatalysts, thesurface of magnetite (Fe3O4) nanoparticles, prepared by a co-precipitation method, was further modified with ferrous oxalate, a highly sensitive non-hazardous reducing agent. The sensitized nanomaterials were characterized by X-ray diffraction, scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy and vibrating sample magnetometry, and used in the catalytic wet hydrogen peroxideoxidation (CWHPO) of RB5 and RY84, in laboratory-scale experiments. The effect of important variables such as catalyst dosage, H2O2 concentration, and contact time was studied in the dye Degradation kinetics. The results showed that it was possible to remove up to 99.7% dye in the presence of 20 mM H2O2 after 240 min of oxidation for a catalyst concentration of 10 g L−1at 25◦C and initial pH value of 9.0.CWHPO of reactive dyes using sensitized magnetic nanocatalysts can be a suitable pre-treatment methodfor complete decolorization of effluents from textile dyeing and finishing processes, once the Optimum operating conditions are established. T2 - 10th International Conference On Physics Of Advanced Materials (ICPAM-10) CY - Iasi, Romania DA - 22.09.2014 KW - Sensitized magnetic nanocatalysts KW - Catalytic wet peroxide oxidation KW - Reactive azo dye degradation PY - 2015 UR - http://www.sciencedirect.com/science/article/pii/S0169433215000483 U6 - https://doi.org/10.1016/j.apsusc.2015.01.036 SN - 0169-4332 VL - 352 SP - 42 EP - 48 PB - Elsevier B.V. AN - OPUS4-38760 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nadejde, C. A1 - Neamtu, Mariana A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Ababei, G. A1 - Panne, Ulrich T1 - Characterization and application of Green Fenton-like catalysts for the removal of water pollutants N2 - Three types of magnetite-chitosan/iron oxalate/iron citrate nanoparticles (NP) were evaluated as magnetic heterogeneous catalysts for water treatment. T2 - PTIM 2015, 1st International Caparica Conference on Pollutant Toxic Ions and Molecules CY - Caparica, Portugal DA - 02.112015 KW - Bisphenol A degradation KW - Nanocatalysts KW - Characterization KW - Fenton oxidation KW - Wastewater PY - 2015 SN - 978-989-99361-6-4 SP - 186 EP - 187 PB - Proteomass AN - OPUS4-40082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nadejde, C. A1 - Neamtu, Mariana A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Paul, Andrea A1 - Ababei, G. A1 - Panne, Ulrich T1 - Green Fenton-like catalysts for the removal of water pollutants N2 - Two types of surface modified magnetite (Fe3O4) nanoparticles, coated with either tannic acid (TA) or dissolved natural organic matter (NOM), were evaluated as magnetic heterogeneous catalysts. Simple and efficient procedures for the synthesis of the magnetic catalysts were employed, their properties being fully assessed by various characterization techniques. The catalytic activity in heterogeneous oxidation of aqueous solutions containing Bisphenol A (BPA) over the catalysts was comparatively studied. The optimum experimental parameters were: 1g/L of catalysts, 10 mM H2O2, under UV irradiation. The highest mineralization rates were observed for Fe3O4-TA catalyst. More than 80% of BPA were removed after 30 minutes of reaction time under the specified experimental conditions. The results showed that the obtained catalysts are suitable candidates for the removal of pollutants in wastewaters by means of heterogeneous reaction T2 - TechConnect World Innovation Conference Nanotech 2015 CY - Washington, DC, Maryland, USA DA - 14.06.2015 KW - Nanocatalysts KW - Characterization KW - Fenton oxidation KW - Wastewater KW - Bisphenol A degradation PY - 2015 SN - 978-1- 4987-4733-2 SN - 978-1-4987-4728-8 VL - 2 SP - 87 EP - 90 PB - CRC Press, Taylor&Francis Group AN - OPUS4-40074 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nadejde, C. A1 - Neamtu, M. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Paul, Andrea A1 - Ababei, G. A1 - Panne, Ulrich T1 - Green Fenton-like magnetic nanocatalysts: Synthesis, characterization and catalytic application N2 - Five iron oxalate core–shell magnetite nanoparticles catalysts are evaluated as magnetic heterogeneous materials. Simple and efficient procedures for the preparation of magnetic iron oxalate coated nanoparticles are presented. The catalysts are fully characterized using various investigation techniques. Additionally, the formation of photo-sensitized oxygen by spin-trapping using electron spin resonance is investigated. The catalytic activity of two model substrates (carbamazepine and bisphenol A) is also evaluated. The effect of operational parameters (catalyst and H2O2 concentration, UVA light) on the degradation performance of the oxidation process is investigated. The obtained reaction rates depend on the nature of the compound and increase with iron oxide shell thickness of the catalyst. Moreover, these materials show a significant activity during two consecutive tests. The optimum experimental parameters are found to be 1.0 g L-1 of catalysts, 10 mM H2O2, under UVA irradiation. More than 99% of both substrates are removed after 30 min of reaction time under the experimental conditions given above. The results obtained show that the catalysts are suitable candidates for the removal of pollutants in wastewaters by means of the Fenton heterogeneous reaction. KW - Magnetic core–shell nanocatalysts KW - Characterization KW - Fenton oxidation KW - Micropollutants KW - Water treatment PY - 2015 U6 - https://doi.org/10.1016/j.apcatb.2015.04.050 SN - 0926-3373 SN - 1873-3883 VL - 176-177 SP - 667 EP - 677 PB - Elsevier CY - Amsterdam AN - OPUS4-33820 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neamtu, Mariana A1 - Nadejde, C. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Paul, Andrea A1 - Ababei, G. A1 - Panne, Ulrich T1 - Green Fenton-like magnetic nanocatalysts: Synthesis, characterization and catalytic application N2 - Five iron oxalate core–shell magnetite nanoparticles catalysts are evaluated as magnetic heterogeneous materials. Simple and efficient procedures for the preparation of magnetic iron oxalate coated nanoparticles are presented. The catalysts are fully characterized using various investigation techniques. Additionally, the formation of photo-sensitized oxygen by spin-trapping using electron spin resonance is investigated. The catalytic activity of two model substrates (carbamazepine and bisphenol A) is also evaluated. The effect of operational parameters (catalyst and H2O2 concentration, UVA light) on the degradation performance of the oxidation process is investigated. The obtained reaction rates depend on the nature of the compound and increase with iron oxide shell thickness of the catalyst. Moreover, these materials show a significant activity during two consecutive tests. The optimum experimental parameters are found to be 1.0 g L−1 of catalysts, 10 mM H2O2, under UVA irradiation. More than 99% of both substrates are removed after 30 min of reaction time under the experimental conditions given above. The results obtained show that the catalysts are suitable candidates for the removal of pollutants in wastewaters by means of the Fenton heterogeneous reaction. KW - Five iron oxalate core–shell magnetite nanoparticles catalysts are evaluated as magnetic heterogeneous KW - Characterization KW - Micropollutants PY - 2015 U6 - https://doi.org/10.1016/j.apcatb.2015.04.050 SN - 0926-3373 SN - 1873-3883 VL - 176-177 SP - 667 EP - 677 PB - Elsevier AN - OPUS4-40072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nadejde, C. A1 - Neamtu, M. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Paul, Andrea A1 - Ababei, G. A1 - Panne, Ulrich T1 - Tannic acid- and natural organic matter-coated magnetite as green Fenton-like catalysts for the removal of water pollutants N2 - The use of magnetic materials as heterogeneous catalysts has attracted increasing attention in the last years since they proved to be promising candidates for water treatment. In the present study, two types of surface-modified magnetite (Fe3O4) nanoparticles, coated with non-hazardous naturally occurring agents—either tannic acid (TA) or dissolved natural organic matter—were evaluated as magnetic heterogeneous catalysts. Chemical synthesis (co-precipitation) was chosen to yield the nanocatalysts due to its well-established simplicity and efficiency. Subsequently, the properties of the final products were fully assessed by various characterization techniques. The catalytic activity in heterogeneous oxidation of aqueous solutions containing a model pollutant, Bisphenol A (BPA), was comparatively studied. The effect of operational parameters (catalyst loading, H2O2 dosage, and UV light irradiation) on the Degradation performance of the oxidation process was investigated. The optimum experimental parameters were found to be 1.0 g/L of catalysts and 10 mM H2O2, under UV irradiation. The highest mineralization rates were observed for Fe3O4-TA catalyst. More than 80 % of BPA was removed after 30 min of reaction time under the specified experimental conditions. The obtained results showed that the two catalysts studied here are suitable candidates for the removal of pollutants in wastewaters by means of heterogeneous reaction using a green sustainable treatment method. KW - Nanocatalysts KW - Photo-Fenton oxidation KW - Wastewater KW - Bisphenol A degradation KW - Environment KW - Mitigation PY - 2015 UR - http://link.springer.com/article/10.1007/s11051-015-3290-0 U6 - https://doi.org/10.1007/s11051-015-3290-0 VL - 17 IS - 12 SP - 476 (1) EP - 476 (10) PB - Springer AN - OPUS4-38758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -