Browsing by Author "Cabrera-Reina, Alejandro"

Now showing 1 - 5 of 5
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    Assessing the photo-activation efficiency of aminopolycarboxylate iron complex mixtures for effective sulfamethoxazole degradation in a pilot-scale UVA-LED photoreactor
    (2024) Herrera-Munoz, Jose; Cabrera-Reina, Alejandro; Salazar-Gonzalez, Ricardo; Miralles-Cuevas, Sara
    This study focused on the degradation of antibiotic sulfamethoxazole (SMX), through the UVA-LED photo-activation of aminopolycarboxylate-based iron complexes in a pilot-scale photoreactor. Fe3+-EDDS, Fe3+-NTA, and a combination of both complexes Fe3+-EDDS and Fe3+-NTA were studied in simulated tap water (TW) and simulated secondary effluent (SE) from a municipal wastewater treatment plant (MWWTP). In TW, 40% SMX degradation was reached after 60 min, with different concentration profiles due to absorption characteristics of each complex. Combining Fe3+-EDDS and Fe3+-NTA an initial rapid SMX degradation was observed followed by a slower phase, improving SMX degradation with respect to each complex separately. In SE and despite presenting similar kinetics, SMX degradation was lower than in TW, due to the presence of organic matter in the water matrix. Moreover, the Fe3+-EDDS and Fe3+-NTA mixture improved SMX degradation with increasing iron concentration. This improvement was attributed to reduced dissolved organic carbon (DOC) from NTA and the lower molar absorption coefficient of Fe3+-NTA. Higher EDDS ratios led to faster complex degradation but did not significantly enhance SMX removal. Conversely, higher NTA ratios reduced SMX degradation. In summary, this study revealed a synergistic effect between Fe3+-EDDS and Fe3+-NTA in SMX degradation. Considering the cost difference between EDDS and NTA, using both compounds offers technical and economic advantages. All treatments reduced chronic toxicity in Selenastrum capricornutum.
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    Assessment of contaminants of emerging concern and antibiotic resistance genes in the Mapocho River (Chile): A comprehensive study on water quality and municipal wastewater impact
    (2024) Herrera-Munoz, Jose; Ibanez, Maria; Calzadilla, Wendy; Cabrera-Reina, Alejandro; Garcia, Veronica; Salazar-Gonzalez, Ricardo; Hernandez, Felix; Campos-Manas, Marina; Miralles-Cuevas, Sara
    The primary objective of this study was to evaluate the persistence and elimination of Contaminants of Emerging Concern (CECs) in municipal wastewater treatment plants (MWWTPs) and their presence in the Mapocho River within the metropolitan area of Santiago, Chile. The use of advanced analytical techniques, based on liquid chromatography coupled to both low and high-resolution mass spectrometry, allowed a comprehensive overview on the presence of CECs in samples. Additionally, a preliminary assessment of the microbiological aspects aimed to determine the presence of indicator microorganisms of fecal contamination, such as Escherichia coli and total coliforms was conducted. Furthermore, a qualitative assessment of Antibiotic Resistant Genes (ARGs) was performed. No CECs were detected upstream to the MWWTPs. However, the results from various wastewater samples (influent, secondary, and tertiary effluents) revealed significant diversity, with 73 CECs detected alongside prevalent ARGs including sult, , sulftt, , qnrB, , and blaTEM. . The presence of CECs and ARGs downstream of the MWWTP in the Mapocho River was mainly attributed to effluent discharge. On the other hand, typical values for a healthy river and a MWWTP with a final disinfection stage were found in terms of fecal contamination. Consequently, the imperative for developing tertiary or quaternary treatments capable of degrading CECs and ARGs to minimize environmental impact is underscored. These findings hold public health significance, offering insights into potential risks and influencing future legislative measures in Chile.
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    Elimination of sulfamethoxazole by anodic oxidation using mixed metal oxide anodes
    (2023) Lauzurique, Yeney; Miralles-Cuevas, Sara; Godoy, Mariel; Sepulveda, Pamela; Bollo, Soledad; Cabrera-Reina, Alejandro; Huilinir, Cesar; Malato, Sixto; Oller, Isabel; Salazar-Gonzalez, Ricardo
    The degradation of sulfamethoxazole (SMX) was studied by anodic oxidation (AO) process using mixed metal oxide (MMO) electrodes with different Ru/Ir ratios. Each electrode was characterized morphological and electrochemically. The electrolyzes were performed in NaCl and Na2SO4 applying two current densities (10 and 50 mA cm-2). The electrode with the highest composition of Ir, Ru/Ir (30/70), showed greater SMX degradation and generation of oxidizing species and was used to treat the antibiotic by AO and AO assisted by solar energy in natural water and actual municipal wastewater effluents.The efficiency in SMX degradation depends on the type of electrode used (MMO) and electrolytic medium. All MMO electrodes, reached almost total degradation of SMX in chloride medium. However, 60 % degradation of SMX in sulfate medium was achieved with anode with lower Ru/Ir ratio. Additionally, degradation of SMX in complex matrices can be successfully carried out by solar-assisted AO and AO processes, without the need to adjust the pH, at room temperature and using anode with lower Ru/Ir ratio. Finally, the AO process assisted by solar energy reduced electrolysis times and the cell's potential, leading to lower energy consumption.
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    New development of a solar electrochemical raceway pond reactor for industrial wastewater treatment
    (ACADEMIC PRESS INC ELSEVIER SCIENCE, 2022) Salazar, Ricardo; Campos, Sebastian; Martinez, Javier; Luna, Francisca; Thiam, Abdoulaye; Aranda, Mario; Calzadilla, Wendy; Miralles-Cuevas, Sara; Cabrera-Reina, Alejandro
    In this work, a solar electrochemical-raceway pond reactor (SEC-RPR) is used to treat textile industrial wastewater by solar photoelectron-Fenton (SPEF) at pilot plant scale for the first time. The SEC-RPR is composed of an electrochemical filter press-cell coupled to RPR, where H2O2 is electro-generated. A complete study about experimental variables such as current, catalyst concentration, pollutant load or liquid depth is conducted based on methyl orange removal, mineralization and decolorization. Validation of the SPEF process using SEC-RPR reached more than 80% of mineralization, as well as the complete decolorization of the solution. The good performance of the SPEF treatment in the new SEC-RPR led to quick degradation kinetics, mainly due to the synergetic action of solar radiation and good distribution of H2O2 electrogenerated in the photoreactor. 100% Methyl Orange degradation was achieved after 150, 60, 45, 30 and 20 min of reaction time applying current density equal to 5, 10, 20, 40 and 60 mA cm(-2), respectively. However, the increase of current density decreased the mineralization current efficiency. Up to 10 aromatics intermediates and 5 short-chain carboxylic acids were identified by LC-MS and HPLC analysis and a reaction pathway for MO mineralization by SPEF is proposed. This study represents an essential preliminary step towards the development of the first SEC-RPR at demo scale.
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    Removal of contaminants of emerging concern by solar photo electro-Fenton process in a solar electrochemical raceway pond reactor*
    (2023) Campos, Sebastian; Lorca, Javier; Vidal, Jorge; Calzadilla, Wendy; Toledo-Neira, Carla; Aranda, Mario; Miralles-Cuevas, Sara; Cabrera-Reina, Alejandro; Salazar, Ricardo
    This work proposes the degradation of different contaminants of emerging concern (CECs) present in a secondary effluent from a municipal wastewater treatment plant in a solar electrochemical raceway pond reactor (SECRPR), applying the solar photo electro-Fenton (SPFE) process. Tap water and a secondary effluent were enriched with 100 mu g L-1 of 7 CECs to study the degradation of these compounds by the SPEF process in a SEC-RPR. Among the results obtained, an elimination over 96% and 90% of 5 CECs (progesterone, estradiol, ibuprofen, diclofenac and estrone) was achieved, while sulfamethazine and carbamazepine were eliminated by 73, 37% and 80, 66% after 1 h of treatment, respectively. In turn, a secondary effluent that already achieved the minimum organic load standards established by Chilean regulations was treated in a SEC-RPR by applying different electrochemical advanced oxidation processes (EAOPs). However, regardless of the applied treatment (SPEF, electro-Fenton and electro-oxidation/H2O2), it was possible to further reduce the organic content and even mineralize it. These experiments were performed at pH 3, with Na2SO4 0.05 mM, Fe2+ 0.05 mM and applying a current density of 20 mA cm-2. The SPEF process implemented in a SEC-RPR is presented as an excellent alternative for the treatment of municipal wastewater, due to the large contact area between the effluent and UV radiation, in addition to the continuous and homogeneous generation of H2O2, which allows for the production of hydroxyl radicals in solution, favoring the degradation and mineralization of pollutants.