DSpace Repository :: Browsing by Author "De Angelis, Laura"

Browsing by Author "De Angelis, Laura"

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Abatement of 2,4-D by H2O2 solar photolysis and solar photo-Fenton-like process with minute Fe(III) concentrations
(2018-11) Serra-Clusellas, Anna; De Angelis, Laura; Lin, Chung-Ho; Vo, Phuc; Bayati, Mohamed; Sumner, Lloyd; Lei, Zhentian; Amaral, Nathalia B.; Bertini, Liliana María; Mazza, José; Pizzio, Luis R.; Stripeikis, Jorge; Rengifo-Herrera, Julian A.; Fidalgo de Cortalezzi, María Marta
"The Photo-Fenton-like (PF-like) process with minute Fe(III) concentrations and the Hydrogen Peroxide Photolysis (HPP), using Xe-lamp or solar light as sources of irradiation, were efficiently applied to eliminate the herbicide 2,4-D from water. PF-like experiments concerning ferric and H2O2 concentrations of 0.6 mg L 1 and 20 mg L 1 respectively, using Xenon lamps (Xe-lamps) as a source of irradiation and 2,4-D concentrations of 10 mg L 1 at pH 3.6, exhibited complete 2,4-D egradation and 77% dissolved organic carbon (DOC) removal after 30 min and 6 h of irradiation respectively whereas HPP (in absence of ferric ions) experiments showed a 2,4-D reduction and DOC removal of 90% and 7% respectively after 6 h of irradiation. At pH 7.0, HPP process achieved a 2,4-D abatement of approximately 75% and a DOC removal of 4% after 6 h. PF-like exhibited slightly improved 2,4-D and DOC removals (80% and 12% respectively) after the same irradiation time probably due to the low pH reduction (from 7.0 to 5.6). Several chlorinated-aromatic intermediates were identified by HPLC-MS. These by-products were efficiently removed by PF at pH 3.6, whereas at neutral PF-like and acid or neutral HPP, they were not efficiently degraded. With natural solar light irradiation, 10 and 1 mg L 1 of 2,4-D were abated using minor H2O2 concentrations (3, 6, 10 and 20 mg L 1 ) and iron at 0.6 mg L 1 in Milli-Q water. Similar results to Xe-lamp experiments were obtained, where solar UV-B þ A light H2O2 photolysis (HPSP) and solar photo-Fenton-like (SPF-like) played an important role and even at low H2O2 and ferric concentrations of 3 and 0.6 mg L 1 respectively, 2,4-D was efficiently removed at pH 3.6. Simulated surface water at pH 3.6 containing 1 mg L 1 2,4-D, 20 mg L 1 H2O2 and 0.6 mg L 1 Fe(III) under natural sunlight irradiation efficiently removed the herbicide and its main metabolite 2,4-DCP after 30 min of treatment while at neutral pH, 40% of herbicide degradation was achieved. In the case of very low iron concentrations (0.05 mg L 1) at acid pH, 150 min of solar treatment was required to remove 2,4-D."
Adsorption with catalytic oxidation in a recirculating bed reactor for contaminated groundwater
(2018-06) Russo, Analia; De Angelis, Laura; Jacobo, Silvia E.
"A novel nanoremediation concept, which is based on in situ trapping of organic contaminants by adsorption and catalytic oxidation in combination with oxidants such as hydrogen peroxide is presented. In earlier works we explored the porous structure of a modified natural clinoptilolite loaded with iron as a supported catalyst (NZ -AFe). The supported catalyst prevents iron release during all the process. This paper presents novel results for BTX (Benzene, Toluene and Xylene) removal from aqueous solution considering that adsorption and oxidation processes are taking place simultaneously. The experiment was achieved by fluxing an aqueous solution of BTX 3.3 mM and hydrogen peroxide, at neutral pH, using the same reservoir. After 870 min, C/C0 reaches near 10% for each pollutant. The system removed 65 mg BTX in the present conditions (13 mg/g NZ-A-Fe). The results indicate that the recirculation bed reactor is an excellent system to remove by adsorption and oxidation processes BTX from water due to high mass transfer coefficients and other advantages when compare to batch reactor experiments."
Glyphosate and AMPA removal from water by solar induced processes using low Fe(III) or Fe(II) concentrations
(2019-11) Serra-Clusellas, Anna; De Angelis, Laura; Beltramo, Mercedes; Bava, Melina Ailén; de Frankenberg, María Josefina; Vigliarolo, Julián; Di Giovanni, Nicolás; Stripeikis, Jorge; Rengifo-Herrera, Julián A.; Fidalgo de Cortalezzi, María Marta
"A solar photo-Fenton-like (SPF-like) process is explored for the removal of 1 mg L−1 glyphosate and its main degradation by-product, aminomethylphosphonic acid (AMPA), from Milli-Q water by means of low Fe(III) concentrations (0.6–2 mg L−1) at pH = 2.8 and variable H2O2 concentrations at the laboratory scale. The research is focused on glyphosate and AMPA oxidation, which present similar toxicity patterns. A 1 mg L−1 glyphosate solution requires 5–6 h of the SPF-like process to be degraded when a minute Fe(III) concentration (0.6 mg L−1) is used in acidic water. Glyphosate abatement time is diminished to 2 h when the Fe(III) concentration is increased to 2 mg L−1. At pH levels above 2.8, the herbicide is partially adsorbed onto the colloids of iron oxyĲhydroxide) compounds. AMPA requires a higher oxidative power than glyphosate to be degraded, and more than 6 h of solar treatment are needed, using 10 mg L−1 h−1 H2O2 and 2 mg L−1 Fe(III) at acidic pH. Solar photo-Fenton (SPF), using 4 mg L−1 Fe(II) and 10 mg L−1 h−1 H2O2 at pH = 2.8, must be applied to achieve practically total AMPA removal in 6 h of irradiation. SPF-like and SPF treatments led to 70% and 80% mineralization, respectively, under the best operational conditions. This work demonstrates that SPF-like and SPF at low Fe(III) or Fe(II) concentrations are effective treatments for the removal of glyphosate from water at acidic pH. Continuous addition of H2O2 is required for AMPA abatement."
Preparation and characterization of nanoencapsulated synthetic soybean oil derivative-an abundant and environmentally friendly phase change material-heat transfer analysis and applications
(2020-10) Bergamo, Jorge; Rossi, Ezequiel; Maffi, Juan M.; De Angelis, Laura; Errea, María Inés
"The thermal properties of a phase change material (PCM), together with its environmental health risks and natural abundance are important aspects to consider when choosing one for a domestic application. In this work, a soybean oil derivative, which comes from one of the most abundant crops on Earth, is proposed as PCM. A heat transfer model was developed to compare the performance of the proposed PCM, under the same boundary and initial conditions, with other materials reported in literature that have well-known disadvantages in terms of flammability, renewability, abundance and environmental care. Results showed that its performance was as good as theirs. Nanocapsules of the PCM coated with TiO2 were prepared and characterized physical, thermal and morphologically. Thermal studies were carried out in a device designed and constructed simulating a water heater, and a reduction of about 70% of the PCM phase thermal resistance due to the TiO2 shell was observed. Furthermore, the calculated thermal energy stored in the device filled with nanoencapsulated PCM was 10.6% higher with respect to the blank, and the total cooling time of the water was increased by over 18% thanks to the PCM."
Trielectrode plasma reactor for water treatment
(2020-04) Giuliani, Leandro; De Angelis, Laura; Díaz Bukvic, Gema; Zanini, Matías; Minotti, Fernando; Errea, María Inés; Grondona, Diana
"The water pollution due to emerging organic pollutants, such as agrochemicals, has become a topic of growing interest worldwide. The increase of pollutants in aquatic systems stimulated the development of new strategies for water remediation. Plasma technology is an advanced oxidation process which has proved to be an efficient method for organic matter degradation. In this work, a novel design of a trielectrode plasma reactor based on a a dielectric barrier discharge extended to a third electrode operated in ambient air is presented. The water to be treated flows through a gutter with low impedance and far from the electrodes connected to the voltage sources.The reactor operates in ambient air; it does not rely on the use of expensive inert gases. The design of the reactor is easily scalable. The performance of the reactor, in terms of the removal efficiency and the energy yield, was tested in an aqueous solution of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), one of the most widely used around the world. The reactor presents a good efficiency in the removal of the herbicide 2,4-D and values of energy yield of about 240 mg/kWh."

Browsing by Author "De Angelis, Laura"

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