Examinando por Autor "Pariente, María Isabel"

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Carbonaceous materials from a petrol primary oily sludge: Synthesis and catalytic performance in the wet air oxidation of a spent caustic effluent
(Elsevier, 2024-08) Jerez, Sara; Ventura, María; Martínez, Fernando; Pariente, María Isabel; Melero, Juan Antonio
Oil refineries produce annually large quantities of oily sludge and non-biodegradable wastewater during petroleum refining that require adequate management to minimize its environmental impact. The fraction solid of the oily sludge accounts for 25 wt% and without treatment for their valorization. This work is focused on the valorization of these solid particles through their transformation into porous materials with enhanced properties and with potential application in the catalytic wet air oxidation (CWAO) of a non-biodegradable spent caustic refinery wastewater. Hence, dealing with the valorization and treatment of both refinery wastes in a circular approach aligned with the petrol refinery transformations by 2050. The obtained oily sludge carbonaceous materials showed improved surface area (260–762 m2/g) and a high Fe content. The good catalytic performance of these materials in CWAO processes has been attributed to the simultaneous presence of surface basic sites and iron species. Those materials with higher content of Fe and basic sites yielded the highest degradation of organic compounds present in the spent caustic refinery wastewater. In particular, the best-performing material ACT-NP 1.1 (non-preoxidated and thermically treated with 1:1 mass ratio KOH:solid) showed a chemical oxygen demand (COD) removal of 60 % after 3 h of reaction and with a higher degradation rate than that achieved with thermal oxidation without catalyst (WAO) and that using an iron-free commercial activated carbon. Moreover, the biodegradability of the treated wastewater increased up to 80% (from ca. 31% initially of the untreated effluent). Finally, this material was reused up to three catalytic cycles without losing metal species and keeping the catalytic performance
Critical review of technologies for the on-site treatment of hospital wastewater: From conventional to combined advanced processes
(Elsevier, 2022) Pariente, María Isabel; Segura, Yolanda; Alvarez, Silvia; Casas, J.A.; Pedro, Z.M. de; Diaz, E.; García, J.; López-Muñoz, M.J.; Marugán, Javier; Mohedano, Ángel Fernandez; Molina, Raúl; Muñoz, M.; Pablos, Cristina; Perdigón-Melón, J.A.; Petre, A.L.; Rodríguez, J.J.; Tobajas, M.; Martínez, F.
This review aims to assess different technologies for the on-site treatment of hospital wastewater (HWW) to remove pharmaceutical compounds (PhCs) as sustances of emerging concern at a bench, pilot, and full scales from 2014 to 2020. Moreover, a rough characterisation of hospital effluents is presented. The main detected PhCs are antibiotics and psychiatric drugs, with concentrations up to 1.1 mg/L. On the one hand, regarding the presented technologies, membrane bioreactors (MBRs) are a good alternative for treating HWW with PhCs removal values higher than 80% in removing analgesics, anti-inflammatories, cardiovascular drugs, and some antibiotics. Moreover, this system has been scaled up to the pilot plant scale. However, some target compounds are still present in the treated effluent, such as psychiatric and contrast media drugs and recalcitrant antibiotics (erythromycin and sulfamethoxazole). On the other hand, ozonation effectively removes antibiotics found in the HWW (>93%), and some studies are carried out at the pilot plant scale. Even though, some families, such as the X-ray contrast media, are recalcitrant to ozone. Other advanced oxidation processes (AOPs), such as Fenton-like or UV treatments, seem very effective for removing pharmaceuticals, Antibiotic Resistance Bacteria (ARBs) and Antibiotic Resistance Genes (ARGs). However, they are not implanted at pilot plant or full scale as they usually consider extra reactants such as ozone, iron, or UV-light, making the scale-up of the processes a challenging task to treat high-loading wastewater. Thus, several examples of biological wastewater treatment methods combined with AOPs have been proposed as the better strategy to treat HWW with high removal of PhCs (generally over 98%) and ARGs/ARBs (below the detection limit) and lower spending on reactants. However, it still requires further development and optimisation of the integrated processes.
Fenton-like catalyst based on a reticulated porous perovskite material: Activity and stability for the on-site removal of pharmaceutical micropollutans in a hospital wastewater
(Elsevier, 2020) Martínez, Fernando; Cruz del Álamo, Ana; González, Carlos; Pariente, María Isabel; Molina, Raúl
Powdered LaCu0.5Mn0.5O3 perovskite was successfully conformed in a reticulated macroporous structure to be tested in an up-flow catalytic packed bed reactor as on-site pre-treatment of pharmaceutical micropollutants in a hospital wastewater. Initially, the effect of the pH, the temperature and the hydrogen peroxide were studied using the hospital wastewater fortified with carbamazepine (CZP) in order to determine the best operation conditions. The reticulated porous perovskite catalyst evidenced a remarkable activity and stability for 70 h on continuous operation in a catalytic packed bed reactor operated at initial pH of ca. 5.5, 70 °C and moderate dosage of hydrogen peroxide (700 mg/L). Under these conditions, the heterogeneous Fenton-like catalytic system achieved an effective removal of pharmaceutical micropollutants of the hospital wastewater in the real range of μg/L, such as antineoplastic drugs, antibiotics, X-ray contrast agent, etc. Most of them were eliminated with removal degrees above 90–95%, being their remaining concentration below the predicted non-effect concentration (PNEC) for aquatic organisms.
Increasing biodegradability of a real amine-contaminated spent caustic problematic stream through WAO and CWAO oxidation using a high specific surface catalyst from petcoke
(Elsevier, 2023) González, Carlos; Pariente, María Isabel; Molina, Raúl; Espina, L.G.; Masa, María; Bernal, Vicente; Melero, Juan Antonio; Martinez, Fernando
Different operating conditions of wet air oxidation and catalytic wet air oxidation have been studied for the treatment of highly concentrated methyldiethanolamine wastewater streams from amine units of acid gas recovery in petrol refineries. These units occasionally generate streams of high methyldiethanolamine content that require special actions to avoid undesirable impacts on the downstream biological process of the petrochemical wastewater treatment plant due to its inhibition effect. The wet air oxidation treatment achieved remarkable removals of methyldiethanolamine, sulfides, chemical oxygen demand and total organic carbon (99%, 95%, 65% and 38%, respectively). Likewise, activated petroleum coke materials from the own refinery plant were tested as catalysts in the process. These materials were prepared under different conditions (chemical activating agent and thermal carbonization process). The catalytic wet air oxidation treatment using an activated petroleum coke was able to remove the methyldiethanolamine at milder operation conditions keeping a similar performance in terms of wastewater treatment removals as compared to the non-catalytic experiments. This technology significantly increased the biodegradability of the treated effluents ranging from 25 to 70 % due to the formation of more biodegradable substrates (acetic acid and ammonium) for further biological treatment.