Examinando por Autor "Pariente, M.I."

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Advanced bio-oxidation of fungal mixed cultures immobilized on rotating biological contactors for the removal of pharmaceutical micropollutants in a real hospital wastewater
(Elsevier, 2021) Cruz del Álamo, A.; Pariente, M.I.; Molina, R.; Martínez, F.
Hospital wastewater represents an important source of pharmaceutical active compounds (PhACs) as contaminants of emerging concern for urban wastewater treatment plants. This work evaluates a fungal biological treatment of a hospital effluent before discharging in the municipal sewer system. This treatment was performed in rotating biological contactors (RBCs) covered with wooden planks in order to promote the attachment of the fungal biomass. These bioreactors, initially inoculated with Trametes versicolor as white rot fungi, have created biofilms of a diversified population of fungal (wood-decaying fungi belonging to Basidiomycota and Ascomycetes) and bacterial (Beta-proteobacteria, Firmicutes, and Acidobacteria) microorganisms. The mixed fungal/bacterial community achieved a stable performance in terms of carbon, nitrogen, and phosphorous reductions for 75 days of continuous operation. Moreover, a remarkable removal of pharmaceutical micropollutants was accomplished especially for antibiotics (98.4 ± 0.7, 83 ± 8% and 76 ± 10 for azithromycin, metronidazole and sulfamethoxazole, respectively). Previous studies have proven a high efficiency of fungi for the removal of microcontaminants as a result of advanced bio-oxidation processes mediated by oxidizing hydroxyl radicals. This study evidences the development of a stable fungal-bacterial mixed culture over wooden-modified RBCs for in-situ removal of pharmaceutical compounds of hospital wastewater under non-sterile conditions and non-strict temperature control, avoiding periodical fungal inoculation due to destabilization and displacement of fungal cultures by indigenous wastewater bacteria.
Assessment of Fe2O3/SiO2 catalyst for the continuous treatment of phenol aqueous solutions in a fixed bed reactor
(ELSEVIER, 2010) Botas, Juan Ángel; Melero, J.A.; Martínez, F.; Pariente, M.I.
Different iron-containing catalysts have been tested for the oxidation of phenol aqueous solutions in a catalytic fixed bed reactor in presence of hydrogen peroxide. All the catalysts consist of iron oxide, mainly crystalline hematite particles, over different silica supports(mesostructured SBA-15 silica and non-ordered mesoporous silica). The immobilization of iron species over different silica supports was addressed by direct incorporation of metal during the synthesis or post-synthesis impregnation. The synthesis conditions were tuned up to yield agglomerated catalysts with iron loadings between 10 and 15 wt. %. The influence of the preparation method and the type of silica support was evaluated in a catalytic fixed bed reactor for the continuous oxidation of phenol in terms of its activity (phenol and total organic carbon degradation) as well as its stability (catalyst deactivation by iron leaching). Those catalyst prepared by direct synthesis either in presence (Fe2O3/SBA-15(DS)) or absence(Fe2O3/SiO2(DS)) of template molecules achieved high catalytic performances (TOC reduction of 65 and 52 %, respectively) with remarkable low iron leaching in comparison with the impregnated iron catalysts. Catalytic results demonstrated that the synthesis method plays a crucial role in the dispersion and stability of active species and hence resulting in superior catalytic performances.
Chemically activated hydrochars as catalysts for the treatment of HTC liquor by catalytic wet air oxidation
(Elsevier, 2023) Mora, A. de; Diaz de Tuesta, J.L.; Pariente, M.I.; Segura, Y.; Puyol, D.; Castillo, E.; Lissitsyna, K.; Melero, J.A.; Martínez, F.
Hydrothermal carbonization (HTC) is a highly efficient and valuable technology for treating wet solid wastes and producing solid carbon-based materials named hydrochar. In this work, a hydrochar coming from the HTC of an anaerobic digestion sludge of wastewater treatment plant was used to assess the influence of several activation agents, a base (KOH) and different chloride salts (FeCl3, ZnCl2, and CuCl2) with the exact molar quantities, to develop materials with enhanced surface area and potential inclusion of metal active species for application in wet air oxidation processes. The KOH as an activating agent increased the surface area of hydrochar up to ca. 1000 m2/g of BET surface area. The employment of CuCl2 and FeCl3 as activating agents allows Cu- and Fe-rich doped materials of remarkable surface areas with 49.1 and 42.5 wt% of each metal, respectively. Likewise, the catalytic behavior of the different synthesized carbon-based materials as metal-free and metal-doped catalysts was evaluated for the Catalytic Wet Air Oxidation (CWAO) of a HTC aqueous liquor from a HTC process of animal manure to produce a valuable stream of higher biochemical methane potential in anaerobic digestion. CWAO effluents increased the proportion of carboxylic acids as final by-products due to the oxidation of more complex organic compounds of the initial effluent (ketones, phenols, aromatics and olefins). The CWAO treatments improve the anaerobic digestion rate in biochemical methane potential tests, although the methane production was limited by the lower TOC concentration of the treated streams after CWAO. This research contributes to developing sustainable and efficient strategies for the HTC-liquor treatment, using its solid hydrochar as catalysts, closing the loop of a Circular Economy.
Comprehensive characterization of an oily sludge from a petrol refinery: A step forward for its valorization within the circular economy strategy
(Elsevier, 2021) Jerez, S.; Ventura, M.; Molina, R.; Pariente, M.I.; Martínez, F.; Melero, J.A.
Refinery treatment plants produce large quantities of oily sludge during the petroleum refining processes. The hazardousness associated with the disposal of these wastes, make necessary the development of innovative technologies to handle it adequately, linked to the concepts of circular economy and environmental sustainability. This work provides for the first time a methodology for the deep characterization of this kind of wastes and consequently new insights regarding its valorization. A review of works dealing with the characterization of this type of wastes has been addressed evidencing the complexity and variability of these effluents. The oily sludge under study contains a high concentration of Chemical Oxygen Demand of 196 g COD/L, a Total Kjeldahl Nitrogen of 2.8 g TKN/kg, a phosphorous content as PO43− of 7 g/kg, as well as a great presence of heavy metals in a different range of concentrations. This sludge is composed of three different phases: oily, aqueous and solid. The oily and the solid phases present high percentages of carbon content (84 and 26%, respectively), related to the presence of alkanes ranged from n-C9 to n-C44. Therefore, it could be possible their valorization by the synthesis of catalyst and/or adsorbents. A dark fermentation process could be also proposed for the oily phase to obtain H2 as an alternative energy source. Finally, the aqueous phase contains low carbon and nutrients concentration. A previous thermal pre-treatment applied to the oily sludge might increase nutrient and organic loading in the aqueous phase due to solid destruction, making this aqueous effluent suitable for a further conventional biological treatment.
Coupling membrane separation and photocatalytic oxidation processes for the degradation of pharmaceutical pollutants
(Elsevier, 2013) Martínez, F.; López-Muñoz, M.J.; Aguado, J.; Melero, J.A.; Arsuaga, J.; Sotto, A.; Molina, R.; Segura, Y.; Pariente, M.I.; Revilla, A.; Cerro, L.; Carenas, G.
The coupling of membrane separation and photocatalytic oxidation has been studied for the removal of pharmaceutical pollutants. The retention properties of two different membranes (nanofiltration and reverse osmosis) were assessed. Comparable selectivity on the separation of pharmaceuticals were observed for both membranes, obtaining a permeate stream with concentrations of each pharmaceutical below 0.5 mg/L and a rejected flux highly concentrated (in the range of 16-25 mg/L and 18-32 mg/L of each pharmaceutical for NF-90 and BW-30 membranes, respectively), when an initial stream of six pharmaceuticals was feeding to the membrane system (10 mg/L of each pharmaceutical). The abatement of concentrated pharmaceuticals of the rejected stream was evaluated by means of heterogeneous photocatalytic oxidation using TiO2 and Fe2O3/SBA-15 in presence of hydrogen peroxide as photo-Fenton system. Both photocatalytic treatments showed remarkable removals of pharmaceutical compounds, achieving values between 80 and 100 %. The nicotine was the most refractory pollutant of all the studied pharmaceuticals. Photo-Fenton treatment seems to be more effective than TiO2 photocatalysis, as high mineralization degree and increased nicotine removal were attested. This work can be considered an interesting approach of coupling membrane separation and heterogeneous photocatalytic technologies for the successful abatement of pharmaceutical compounds in effluents of wastewater treatment plants.
Heterogeneous catalytic Wet Peroxide Oxidation Systems for the Treatment of an Industrial Pharmaceutical Wastewater
(ELSEVIER, 2009) Melero, J.A.; Martínez, F.; Botas, Juan Ángel; Molina, R.; Pariente, M.I.
The aim of this work was to assess the treatment of a wastewater coming from a pharmaceutical plant through a continuous heterogeneous catalytic wet peroxide oxidation (CWPO) process using a Fe2O3/SBA-15 nanocomposite catalyst. This catalyst was preliminary tested in a batch stirred tank reactor (STR), to elucidate the influence of significant parameters on the oxidation system, such as temperature, initial oxidant concentration and initial pH of the reaction medium. In that case, a temperature of 80ºC using an initial oxidant concentration corresponding to twice the theoretical stoichiometric amount for a complete carbon depletion and initial pH of ca. 3 allow obtaining TOC degradation around 50% after 200 minutes of contact time. Thereafter, the powder catalyst was extruded with bentonite to prepare pellets that could be used in a fixed bed reactor (FBR). Results in the up-flow FBR indicate that the catalyst shows high activity in terms of TOC mineralization (ca. 60% under steady-state conditions), with an excellent use of the oxidant and high stability of the supported iron species. The activity of the catalyst is kept constant, at least, for 55 hours of reaction. Furthermore, BOD5/COD ratio is increased from 0.20 up to 0.30, whereas the Average Oxidation Stage (AOS) changed from 0.70 to 2.35. These two parameters show a high oxidation degree of organic compounds in the outlet effluent, which enhances its biodegradability, and favours the possibility of a subsequent coupling with a conventional biological treatment.
New strategies for the management of a primary refinery oily sludge: A techno-economical assessment of thermal hydrolysis, Fenton, and wet air oxidation treatments
(Elsevier, 2023) Jerez, S.; Ventura, M.; Martínez, F.; Melero, J.A.; Pariente, M.I.
Petroleum refinery wastewater treatment plants produce a significant amount of oily sludge, a hazardous waste that requires proper disposal. It is necessary to develop technologies to treat and valorise it, avoiding the current environmental problems associated with its landfill disposal. This work explores the application of different advanced technologies for the pre-treatment and further valorisation of this oily sludge, which includes thermal hydrolysis, Fenton oxidation, and wet air oxidation. These treatments reduce the solid content by 51–78%. Moreover, the increasing dewaterability and settleability facilitate phase separation, thus enabling further valorisation, obtaining an aqueous effluent more biodegradable (ca. 63%). A conceptual design based on experimental data obtained at bench scale has been developed for the three pre-treatment systems under study. Techno-economic analysis of the three advanced treatments gave unitary costs ranging from 78 €/m3 for thermal hydrolysis to 192 €/m3 for the Fenton treatment, which are all in the low range of the current management cost (70–350 €/m3 ). Thus, the techno-economic analysis developed in this study demonstrates its feasibility compared to the current management of oily sludge from API separators. Thermal hydrolysis can be a low-cost and suitable strategy for producing biodegradable effluent that can be directly treated in the conventional biological treatment plant of the refinery. However, WAO might be a more appropriate option to recover carbon and nutrients for further valorisation in advanced biological processes.
Novel 3D electro-Fenton reactor based on a catalytic packed bed reactor of perovskite/carbon microelectrodes for the removal of carbamazepine in wastewater
(Elsevier, 2024-08) Cruz del Álamo, A.; Puga, A.; Dias Soares, C.M.; Pariente, M.I.; Pazos, M.; Molina, R.; Sanromán, M.A.; Martínez, F.; Delerue-Matos, C.
This presents the efficacy of a 3D-ElectroFenton (3D-EF) reactor with active perovskite/carbon black/PTFE microelectrodes for the removal of carbamazepine (CZP) present in wastewater. Incorporating particle microelectrodes in the reactor enhanced the electron transfer and improved the electrocatalytic efficiency, leading to a more effective CZP removal. The optimal operational conditions were meticulously determined, including current intensity (0.05 – 0.3 A) and particle loading (0 – 1.5 g), to optimize the process and minimize energy consumption. The findings reveal that a current intensity of 0.2 A was the most effective, achieving 90% of CZP removal in 60 min and 3.86 kWh/mg of CZP. A higher current intensity of 0.3 A significantly increased the energy consumption (6.02 kWh/mg of CZP) for a total and faster CZP removal. The 3D-EF reactor was also operated continuously with ultrapure water and real urban wastewater fortified with CZP. A remarkable 62% CZP removal after 96 h on continuous operation was achieved with urban wastewater. Physicochemical and electrochemical characterization of microelectrodes demonstrated their high mechanical integrity and chemical stability. Our study underscores the potential of a 3D-EF system as a promising advanced oxidation process to address the continuous removal of antidepressant carbamazepine as one of the more resistant micropollutants of emerging concern in wastewater treatment, offering hope for a more efficient and sustainable future
Treatment of an agrochemical wastewater by integration of heterogeneous catalytic wet hydrogen peroxide oxidation and rotating biological contactors
(Elsevier, 2013-06-15) Melero, J.A.; Pariente, M.I.; Siles, J.A.; Molina, R.; Botas, J.A.; Martinez, F.
The treatment of a non-biodegradable agrochemical wastewater has been studied by coupling of heterogeneous catalytic wet hydrogen peroxide oxidation (CWHPO) and rotating biological contactors (RBCs). The influence of the hydrogen peroxide dosage and the organic content of the wastewater (dilution degree) were studied. The CWHPO of the raw wastewater at 80 ºC and using a moderate amount of oxidant (0.23 gH2O2/gTOC) reduced significantly its total organic carbon content and increased its biodegradability. Likewise, the iron leaching of the heterogeneous catalyst (Fe2O3/SBA- 15) was less than 2 mg/L in the treated effluent. Under the best operating conditions, the resultant CWHPO effluent was successfully co-treated by rotating biological contactors (RBCs) using a simulated municipal wastewater with different percentages of the CWHPO effluent (2.5, 5 and 10 % v/v). The RBCs showed high stability for the treatment of the highest percentage of the CWHPO effluent, achieving total organic carbon (TOC) and total nitrogen (TN) reductions of ca. 78 % and 50 %, respectively. The integration of both processes on a continuous mode has been successfully accomplished for the treatment of the as-received agrochemical wastewater.