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

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

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

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

Análisis de aguas residuales con fines epidemiológicos: aplicaciones a la estimación del consumo de sustancias de abuso y en salud pública en general. Red española ESAR-Net

En este artículo se presenta la metodología de análisis de aguas residuales con fines epidemiológicos (wastewater-based epidemiology, WBE) y su potencial para abordar diversos aspectos relacionados con la salud pública. Esta metodología permite obtener datos a una escala temporal y espacial relativamente pequeña (típicamente datos diarios-semanales sobre un municipio) de hábitos de consumo de sustancias de abuso, ilegales (como la cocaína o el cannabis) o legales (como el alcohol) a través de la determinación de biomarcadores de consumo (el compuesto original no metabolizado o alguno de sus metabolitos) en el agua residual. Aparte de discutir los fundamentos, ventajas y limitaciones de WBE, se comentan los precedentes más relevantes a nivel internacional, y las actividades más destacables en España en este ámbito. Finalmente, se exponen, los objetivos de la Red Española de Análisis de Aguas Residuales con Fines Epidemiológicos (ESAR-Net), una "Red de Excelencia" que agrupa a investigadores españoles con amplia experiencia en el área de WBE, así como las perspectivas de futuro de esta metodología puede tener para mejorar las competencias de la Salud Pública en España

El análisis de aguas residuales con fines epidemiológicos: presente y futuro en España

El análisis de aguas residuales con fines epidemiológicos es actualmente una herramienta fiable y complementaria a las metodologías basadas en indicadores tradicionales para el control de diferentes sustancias entre las que cabe destacar las drogas. Si bien varios países europeos la utilizan como herramienta de trabajo para la monitorización de drogas de abuso, en España su uso se limita principalmente a estudios realizados por diferentes grupos de investigación, tal y como se describe en el caso práctico puesto de ejemplo en el artículo. Sin embargo, el potencial de la metodología ha quedado evidenciado en los estudios científicos llevados a cabo tanto a nivel español como internacional y, aunque son necesarios más estudios para llegar a conocer todo su potencial, se prevé pueda ser incorporada como herramienta de trabajo complementaria a las que habitualmente se utilizan. En este sentido, la Red Española de Análisis de Aguas Residuales (ESAR-Net), creada en 2017 y formada por diferentes grupos de investigación españoles, pretende contribuir al conocimiento y aplicación de esta metodología en España a través de actividades científicas y de divulgación.Este estudio ha sido financiado por la Agencia Estatal de Investigación (AEI) a través del programa Redes de Excelencia (CTM2016-81935-REDT)S

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

Enhanced oil recovery with nanofluids based on aluminum oxide and 1-dodecyl-3-methylimidazolium chloride ionic liquid

Surface-active ionic liquids (SAILs) have multiplied the possibilities of surfactant enhanced oil recovery (EOR) methods. Among their multiple promising features, the possibility of functionalization and their stability at harsh conditions should be highlighted for the application. They have been successfully applied to increase oil recovery by improving crucial parameters such as: formulation stability, reduction of water–oil interfacial tension, and wettability. Recently, nanoparticles have attracted attention for EOR applications due to their capacity to modify the properties of rock surfaces. However, to date no research has been conducted on the combination of SAILs with nanoparticles for EOR. In this work, the combination of the SAIL 1-dodecyl-3-methylimidazolium chloride, [C12mim]Cl, with Al2O3 nanoparticles is proposed for EOR. Stable dispersions in brine were achieved, using the polymer polyvinylpyrrolidone (PVP) as a stabilizing agent, and characterized through density and dynamic viscosity measurements. According to stability and interfacial tension studies, a nanofluid consisting of 0.05 wt% [C12mim]Cl, 0.05 wt% Al2O3 and 1.0 wt% PVP, in brine (5.0 wt% NaCl) was proposed for EOR in carbonate reservoirs. The presence of nanoparticles reduced the adsorption of the surfactant-polymer formulation on carbonate rocks and changed the aged rock wettability from oil-wet to water-wet. An additional oil recovery of 10.4 %OOIP was achieved with the surfactant-polymer formulation, in comparison with 14.8 %OOIP obtained with the nanofluidS

Acetone + 1-ethyl-3-methylimidazolium acetate phase diagram: A correlation challenge

Several physical properties and the isobaric vapour-liquid equilibria at 101.32, 50, and 30 kPa were measured for the binary system consisting of acetone and the ionic liquid 1-ethyl-3-methyl-imidazolium acetate. Liquid-liquid equilibrium data were also measured at temperatures from 298.15 up to 328.35 K and atmospheric pressure. An hourglass-shaped miscibility gap was found. The simultaneous correlation of both VLE and LLE regions at 101.32 kPa was addressed. The NRTL model, considering different options to formulate the temperature dependence of the parameters, was tested and found unable to correlate the whole set of equilibrium data. A detailed analysis of the excess Gibbs energy demonstrated the limitations of the classical equation and allowed the definition of a new model with a correction term. A unique set of parameters were used to simultaneously correlate both sets of equilibrium data with very low deviations from experimental data. Moreover, the corrected NRTL function overcomes some uncertainty problems that may occur in liquid-liquid equilibrium calculations.The authors would like to thank “Generalitat Valencia: Consellería de Educación, Investigación, Cultura y Deporte” for the PhD grant (ACIF/2019/040) and 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 traineeship