54 research outputs found
Nanomaterial Synthesis in Ionic Liquids and Their Use on the Photocatalytic Degradation of Emerging Pollutants
The unique properties of ionic liquids make them suitable candidates to prepare nanoscale materials. A simple method that uses exclusively a corresponding bulk material and an ionic liquid—in this case, [P6,6,6,14]Cl—was used to prepare AgCl nanoparticles and AgCl@Fe3O4 or TiO2@Fe3O4 magnetic nanocomposites. The prepared nanomaterials were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet–visible spectroscopy, and X-ray photoelectron spectroscopy. The photodegradation of atenolol as a model pharmaceutical pollutant in wastewater was investigated under ultraviolet–visible light irradiation using the different synthesized nanocatalysts. In the presence of 0.75 g·L−1 AgCl nanoparticles, a practically complete degradation of 10 ppm of atenolol was obtained after 30 min, following pseudo-first-order reaction kinetics. The effect of different variables (concentrations, pH, oxidant agents, etc.) was analyzed. The recyclability of the nanocatalyst was tested and found to be successful. A degradation mechanism was also proposed. In order to improve the recovery stage of the nanocatalyst, the use of magnetic nanocomposites is proposed. Under the same experimental conditions, a slightly lower and slower degradation was achieved with an easier separation. The main conclusions of the paper are the suitability of the use of ionic liquids to prepare different nanocatalysts and the effectiveness of these at degrading an emerging pollutant in wastewater treatmentThis research was funded by Xunta de Galicia through grant numbers ED431B 2020/21, ED431B 2020/21 and ED431C2017/36, the Spanish Agencia Estatal de Investigación (ref. CTM2017-84763-C3-R-2), and FEDER/ERDF funds (European Regional Development Fund)S
Nanofluid based on 1-dodecylpyridinium chloride for enhanced oil recovery
[Abstract] The use of nanoparticles is considered promising for enhanced oil recovery (EOR), especially when they are combined with surfactants. However, the combination of nano-sized material with surface-active ionic liquids (SAILs) is an unexplored EOR method. In this work, the advantages of mixing Al2O3 nanoparticles with the SAIL 1-dodecylpyridinium chloride were investigated. Stable nanofluids in brine could only be achieved using the polymer polyvinylpyrrolidone (PVP) as a stabilizing agent. It was found that the addition of nanoparticles (and PVP) to the surfactant formulation helped to: slightly increase its viscosity, enhance its water-oil interfacial tension (IFT) reduction capacity, and reduce the adsorption on carbonate rocks (adsorption on sandstone was found to be excessive). IFT was selected as target property to minimize for the design of EOR formulations. Core flooding tests were carried out with surfactant (0.5 wt% [C12py]Cl), surfactant-polymer (0.5 wt% [C12py]Cl, 1.0 wt% PVP) and nanofluid (0.05 wt% Al2O3, 1.0 wt% PVP, 0.5 wt% [C12py]Cl) formulations in brine (0.5 wt% NaCl). Additional oil recoveries of 3.4%, 7.4% and 12.0% OOIP were achieved, respectively, the nanofluid formulation being the most promising for the application. Moreover, it was found capable of changing the wettability of carbonate rocks from oil-wet to intermediate-wet. The significance of this work lies in showing the new possibilities resulting from the combination of SAILs and nanoparticles for EOR, specifically the combination of [C12py]Cl with Al2O3.Ministerio de Ciencia e Innovación; PGC2018-097342-B-I0
Laccase-mediator system for the ionic liquid-assisted treatment of a technical lignin with partial dissolution
The valorisation of lignin is a key aspect in the optimal exploitation of the paradigm of a biorefinery based on lignocellulosic biomass. In this work, the treatment of the technical lignin Indulin AT with a recombinant laccase, or with a combination of this enzyme with the mediator 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), has been carried out at 25 °C in a mildly acidic buffered aqueous medium. The presence of the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) has also been investigated. Due to the limited solubility of Indulin AT in water, only partial dissolution occurred. In the lignin recovered after the treatments, a preferential diminution of the guaiacyl units was observed. In the analysis of the aqueous phases, a variety of phenolic compounds were identified, deriving from either guaiacyl or p-hydroxyphenyl units, although in moderately low concentrations. The highest assigned concentrations, always achieved when using the laccase-ABTS system (versus the treatment with no mediator), corresponded to different phenolic compounds, depending on whether the ionic liquid was involved or not in the treatment. In general, the overall concentration of phenolic compounds (measured as equivalents of gallic acid) was much greater after treatments involving the ionic liquid.This work was supported by Xunta de Galicia through grant numbers ED431B 2017/023 and ED431E 2018/01 (CRETUS Strategic Partnership), and by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020. C.A.P. and H.R. are grateful to “Agrupación Europea de Cooperación Territorial – Galicia - Norte de Portugal (GNP-AECT)” for support of stays at the Centre of Biological Engineering of the University of Minho via the Iacobus programme. The use of RIAIDT-USC analytical facilities is also acknowledged.info:eu-repo/semantics/publishedVersio
Towards improving the sustainability of bioplastics: Process modelling and life cycle assessment of two separation routes for 2,5-furandicarboxylic acid
Within the framework of an economy excessively dependent on fossil resources, the concept of sustainable development, aimed at obtaining environmentally friendly consumer goods, has given rise to the development of biorefineries. These facilities are based on the production of biofuels and platform chemicals from the most abundant raw material on the planet: biomass. The use of biomass such as wood or lignocellulosic residues makes it possible to seize opportunities offered by the implementation of renewable feedstocks, which in many cases can be embedded within the perspective of circular economy, through the exploitation of residual fractions. Among the multiple basic chemicals that can be obtained from biomass, 2,5-furandicarboxylic acid (FDCA) has a great potential, as it is the precursor of poly(ethylene furanoate) (PEF) polymer, which is considered a feasible substitute for poly(ethylene terephthalate) (PET). The purpose of this study is the simulation and environmental analysis of two separation routes for FDCA production with the objective of identifying the environmental hotspots at an early stage of the process design. The present study addresses the modelling of FDCA production from hydroxymethyl furfural (HMF) by heterogeneous catalysis using commercial Aspen Plus® V9 software. Two different downstream separation options resulting in purified FDCA were simulated: crystallization (Scenario A) and distillation (Scenario B). The estimation of the mass and energy balances were considered in the development of the data inventories required to conduct Life Cycle Assessment (LCA). LCA-assisted decision making identifies the conceptual configuration that would eventually lead to the least environmental burden. In the case of Scenario A, the stage with the highest environmental burden was the reaction unit, due to the use of HMF. In Scenario B, on the other hand, the separation stages contributed most to the impact due to their high energy demand. The combination of process simulation and LCA allowed acquiring a detailed vision of the process, through the analysis of the sensitivity of the environmental profile to different process parameters. The operating pressure in flash and distillation units for both scenarios affects plant operation by influencing total energy consumption and FDCA production. The sensitivity of environmental outcomes to these parameters was also studied, resulting in small variations. Thus, the results of this assessment provide strategic information of the early decision-making process on potential configurations for industrial-scale FDCA productionThis research was supported by EnzOx2 BBI JU-Project [grant agreement No 720297]. The authors belong to the Galician Competitive Research Group GRC ED431C 2017/29 and to the CRETUS Strategic Partnership [ED431E 2018/01]. All these programs are co-funded by FEDER (EU)S
Recovery of dialkylimidazolium-based ionic liquids from their mixtures with acetone or water by flash distillation
In a number of applications for which novel processes based on ionic liquids have been proposed, the recovery of the ionic liquid from its mixture with a molecular solvent is a step of critical importance for the viability of the process. In this work, feasibility and conditions for such recovery by simple flash vapourisation have been explored for the particular case of three dialkylimidazolium-based ionic liquids (namely 1-ethyl-3-methylimidazolium thiocyanate ([C2mim][SCN]), 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), and 1-butyl-3-methylimidazolium acetate ([C4mim][OAc])) and either acetone or water as representative molecular solvents of industrial relevance. The isobaric vapour-liquid equilibria of the binary systems acetone + ([C2mim][SCN] or [C4mim][OAc]) and water + ([C2mim][OAc] or [C4mim][OAc]) have been determined at three different pressures (101.32, 50.00, and 30.00 or 25.00 kPa), and the data have been suitably correlated by means of the NRTL thermodynamic model. These correlations have been used in the software Aspen Plus for the development of reliable simulations of a flash unit to perform the desired separations. The results indicate the difficulty in getting the ionic liquids recovered with high purity, even if operating the flash at a pressure as low as 5 kPa and at temperatures close to the range where the thermal stability of the ionic liquids starts to get compromisedThe authors acknowledge Xunta de Galicia for support through project ED431B 2020/021. M.K.W. is grateful to the Erasmus + programme of the European Union for the award of a mobility traineeshipS
Consequences of Nitrogen Doping and Oxygen Enrichment on Titanium Local Order and Photocatalytic Performance of TiO2 Anatase
This work was financially supported by Spanish MINECO (MAT2013-40950-R, MAT2016-78155-C2-1-R, and CTQ2014-52956-C3-1-R), Gobierno del Principado de Asturias (GRUPIN14-060 and GRUPIN14-078), FEDER and South Ural State University thanks for the support the Ministry of Education and Science of the Russian Federation (grant No 16.2674.2014/K
ESAR-Net: a collaborative effort to expand the application of wastewater epidemiology in Spain
Resumen del trabajo presentado en el SETAC Europe 30th Annual Meeting, celebrado en modalidad virtual del 3 al 7 de mayo de 2020.Data obtained from wastewater analysis can provide rapid and complementary insights in illict drug consumption at community level. Drug use has been assessed through wastewater analysis at national level in, for example, Australia, Belgium, Finland and South Korea and has also provided annually a one week snapshot of illicit drug volumes consumed in European cities (http://www.emcdda.europa.eu/topics/ pods/waste-water-analysis). However, a wastewater monitoring program did not exist in Spain, but leading experts have formed a network (https://www.esarnet.es/) to promote wastewater-based epidemiology at national level and communicate their findings to authorities and policymakers. Within Europe, Spain is an important country of transit of both cocaine and cannabis, due to its cultural, linguistic and colonial ties to Latin America and its proximity to Morocco. The quantity of seized cocaine and cannabis and prevalence of use, locates Spain at the top of Europe. In this work, a national wastewater campaign has been performed to get more insight on the consumption of illicit drugs and NPS within Spain for the first time. Wastewater results from 14 Spanish cities were compared with previously reported data and other national indicators. The cities, located in 7 of the 17 autonomous communities, cover approximately 6 million inhabitants (12.8 of the Spanish population). Untreated wastewater samples were analyzed for urinary biomarkers of amphetamine, methamphetamine, MDMA, cocaine and cannabis. In addition to these conventional drugs, weekend samples were monitored for several new psychoactive substances (NPS) (i.e. phenethylamines and cathinones). The selected NPS are known as possible replacement of these conventional drugs or among those previously reported. Finally, enantiomeric profiling of amphetamine was performed for one city in order to assure the results were due to consumption and not illegal dumping of production residues. This demonstrates another application of wastewater-based epidemiology, which allows to identify the originof drugs in wastewater.This work has been supported by the Spanish State Research Agency (Agencia Estatal de Investigación, AEI) through the “Redes de Excelencia” programme, ESAR-Net, ref. CTM2016-81935-RED
Assessing alcohol consumption through wastewater-based epidemiology: Spain as a case study
Background In this study, an alternative and complementary method to those approaches currently used to estimate alcohol consumption by the population is described. This method, known as wastewater-based epidemiology (WBE), allows back-calculating the alcohol consumption rate in a given population from the concentrations of a selected biomarker measured in wastewater. Methods Composite (24-h) wastewater samples were collected at the inlet of 17 wastewater treatment plants located in 13 Spanish cities for seven consecutive days in 2018. The sampled area covered 12.8% of the Spanish population. Wastewater samples were analyzed to determine the concentration of ethyl sulfate, the biomarker used to back-calculate alcohol consumption. Results Alcohol consumption ranged from 4.5 to 46 mL/day/inhabitant. Differences in consumption were statistically significant among the investigated cities and between weekdays and weekends. WBE-derived estimates of alcohol consumption were comparable to those reported by its corresponding region in the Spanish National Health Survey in most cases. At the national level, comparable results were obtained between the WBE-derived annual consumption rate (5.7 ± 1.2 L ethanol per capita (aged 15+)) and that reported by the National Health Survey (4.7 L ethanol per capita (aged 15+)). Conclusions This is the largest WBE study carried out to date in Spain to estimate alcohol consumption rates. It confirms that this approach is useful for establishing spatial and temporal patterns of alcohol consumption, which could contribute to the development of health care management plans and policies. Contrary to established methods, it allows obtaining information in a fast and relatively economical wayThis work has been supported by the Spanish State Research Agency (AEI) (This work has been supported by the Spanish State Research Agency , CTM2017-84763-C3-1-R, CTM2017-84763-C3-3-R and CTM2017-84763-C3-2-R), Generalitat de Catalunya (expedient number SA-2018-780 and Consolidated Research Group 2017 SGR 01404-Water and Soil Quality Unit), and Galician Council of Culture, Education and Universities (ED481D 2017/003 and EM2014/004). Several of these projects are cofounded by the European Regional Development FundS
Monitorización del consumo de sustancias de abuso legales e ilegales en España a través de las aguas residuales en el marco de la red ESAR-Net
Trabajo presentado en el 4th Congreso Internacional y XLIX Jornadas Nacionales de Socidrogalcohol - VIII Congreso Nacional Patología Bio-Psicosocial, celebrado en Tenerife del 06 al 08 de octubre de 2022
Assessing population exposure to phthalate plasticizers in thirteen Spanish cities through the analysis of wastewater
Phthalates are widely used plasticizers that produce endocrine-disrupting disorders. Quantifying exposure is crucial to perform risk assessments and to develop proper health measures. Herein, a wastewater-based epidemiology approach has been applied to estimate human exposure to six of the mostly used phthalates within the Spanish population. Wastewater samples were collected over four weekdays from seventeen wastewater treatment plants serving thirteen cities and ca. 6 million people (12.8 % of the Spanish population). Phthalate metabolite loads in wastewater were transformed into metabolite concentrations in urine and into daily exposure levels to the parent phthalates. Considering all the sampled sites, population-weighted overall means of the estimated concentrations in urine varied between 0.7 ng/mL and 520 ng/mL. Very high levels, compared to human biomonitoring data, were estimated for monomethyl phthalate, metabolite of dimethyl phthalate. This, together with literature data pointing to other sources of this metabolite in sewage led to its exclusion for exposure assessments. For the remaining metabolites, estimated concentrations were closer to those found in urine. Their 4-days average exposure levels ranged from 2 to 1347 μg/(day∙inh), exceeding in some sites the daily exposure thresholds set for di-i-butyl phthalate and di-n-buthyl phthalate by the European Food Safety Authority.Financial support. This study was supported by MCIU/AEI (projects CTM2016-81935-REDT, CTM2017-84763-C3-1-R, CTM2017-84763-C3-2-R, CTM2017-84763-C3-3-R, and CEX2018-000794-S), Galician Council of Culture, Education and Universities (ED481D 2017/003 and ED431C2017/36), Generalitat Valenciana (projects Prometeo/2018/155 and Prometeo/2019/040) and Universitat Jaume I (project UJI-B2018-55). Several of the above mentioned projects are cofunded by FEDER/ERDF. Sampling, sample and data provision and/or analytical support: Viaqua and Concello de Santiago de Compostela, EMAYA (Palma), Jordi Palatsi from Aqualia (Lleida WWTP), Cristian Mesa and Angela Vidal from Aigues de Barcelona (Barcelona WWTP), Iñigo González (Consorcio de Aguas de Bilbao-Bizkaia), the Public Entity of Wastewater Treatment (EPSAR) of the Generalitat Valenciana and especially Fernando Llavador. Luis Aceiton, Enrique Albors, Angel Jiménez, Maria José Tarrega, Sonia Tristante and all the personal of the WWTPs (Aguas de Valencia, Spain), are acknowledged for their help with the sampling. Sociedad de Fomento Agrícola Castellonense (FACSA, Castellon), and especially WWTP operators Santiago Querol and Sara Gargallo are acknowledged for providing wastewater samples from Castellón, as well as Subdirección General de Gestión del Agua, Ayuntamiento de Madrid, for allowing the collection of samples from Madrid centro.Peer reviewe
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