Person: García Cervilla, Raúl
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First Name
Raúl
Last Name
García Cervilla
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Ingeniería Química y de Materiales
Area
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15 results
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Item Abatement of chlorobenzenes in aqueous phase by persulfate activated by alkali enhanced by surfactant addition(Journal of Environmental Management, 2022) García Cervilla, Raúl; Santos López, Aurora; Romero, Arturo; Lorenzo Fernández, DavidSites polluted by dense non-aqueous phases (DNAPLs) constitute an environmental concern. In situ chemical oxidation (ISCO) application is limited since oxidation often occurs in the aqueous phase and contaminants are usually hydrophobic. In this work, ISCO enhanced by the surfactant addition (S–ISCO) was studied for a complex liquid mixture of chlorinated organic compounds (COCs) using persulfate (PS) activated by alkali (PSA) as oxidant and Emulse-3® as a commercial non-ionic surfactant. The reaction between E3 and PSA was investigated in the absence and presence of solubilized COCs in the following concentration ranges: COCs 1.2–50 mM, PS 84–336 mM, NaOH:PS molar ratio of 2, and surfactant concentration 1–10 g⋅L− 1. In the experiments carried out in the absence of COCs, the unproductive consumption of PS was studied. The higher the surfactant concentration, the lower the ratio PS consumed to the initial surfactant concentration due to more complex micelle structures hindering the oxidation of surfactant molecules. This hindering effect was also noticed in the oxidation of solubilized COCs. The reduction of chlorobenzenes by PSA was negligible at surfactant concentrations above 2.5 g⋅L− 1, independently of the COCs concentration solubilized. Instead, a surfactant concentration of about 1 and PS concentration of 168 mM yielded a significant decrease in the time required to abate a mass of DNAPL, compared with an ISCO process, with a bearable increase in the unproductive consumption of PSItem Remediation of the Alluvial Aquifer of the Sardas Landfill (Sabiñánigo, Huesca) by Surfactant Application(Sustainability, 2022) Guadaño, Joaquín; Gómez, Jorge; Fernández, Jesús; Lorenzo Fernández, David; Dominguez Torre, Carmen M.; Cotillas Soriano, Salvador; García Cervilla, Raúl; Santos López, AuroraSardas Landfill at Sabiñánigo Huesca is polluted with Dense Non-Aqueous Liquid Phases (DNAPLs) composed of a complex mixture of chlorinated organic compounds (COCs). This DNAPL was produced as liquid waste from lindane production being dumped decades ago in the unlined landfills close to the lindane factory. This DNAPL migrated by gravity through the subsurface and accumulated in the contact between the alluvial and marls layers (about 15 m b.g.l.). Seven injections of an aqueous emulsion of a biodegradable non-ionic surfactant (E-Mulse 3®) were carried out at the most polluted areas of the Sardas alluvial. Injections were carried out between April and November 2021 using different surfactant concentrations (6.7, 20, 25 and 50 g/L), injection volumes (0.2 to 7 m3) and injection flow rates (0.08–0.85 m3/h). Injected fluids were extracted in the same well or surrounding wells, and the time elapsed between surfactant injection and extraction varied between 24 and 72 h. A total of 22 m3 were injected into the alluvial, and more than double this injected volume was extracted. Injection and extraction points were in the contact between the marls and the alluvial layer. Extracted fluid accumulated in tanks, and phases separated. DNAPL recovered here was mobilized rather than solubilized and managed as toxic waste. The aqueous supernatant was treated in a wastewater treatment plant with physicochemical treatment (including adsorption in activated carbon) before being discharged into the environment. The transport of the injected fluids was monitored by conductivity profiles using bromide (260–538 mg·L−1) as a conservative tracer. High radial dispersion of the injected fluid was found. Surfactant losses by adsorption in the alluvial and absorption in DNAPL were noticed, and both surfactant and contamination did not escape from the capture zone. Monitoring since 2018 of the COCS in groundwater and the DNAPL presence in the contact between alluvial and marls layers showed a significant reduction of COCs in the treated zone with the surfactant injections.- Project number: PIMCD328/23-24
Item Elaboración de una metodología basada en el aprendizaje autónomo de herramientas informáticas para fomentar las competencias digitales de los estudiantes de Ingeniería Química(2024) Lorenzo Fernández, David; Checa Fernández, Cristina Alicia; Cotillas Soriano, Salvador; Domínguez Torre, Carmen María; Herraíz Carboné, Miguel; García Cervilla, Raúl; Martínez Rodríguez, Mercedes; Rodríguez Vega, Sergio; Sánchez Yepes, Andrés; Santos López, Aurora Item Partition of a mixture of chlorinated organic compounds in real contaminated soils between soil and aqueous phase using surfactants: Influence of pH and surfactant type(Journal of Environmental Chemical Engineering, 2021) García Cervilla, Raúl; Santos López, Aurora; Romero, Arturo; Lorenzo Fernández, DavidThe equilibrium between surfactant adsorption and contaminants desorption was studied. Two soil samples from a polluted site with residues from lindane production, compounded of a complex mixture of 28 chlorinated organic compounds (COCs) and different concentration of COCs in soil (2.27 and 34.69 mmolCOCs⋅kg− 1 soil), were used. Soil was in contact with aqueous surfactant solutions (1–15 g⋅L− 1) of nonionic (E-Mulse® 3, and Tween® 80) and anionic (sodium dodecylsulfate) surfactants. Due to alkaline pH promoting the dehydrochlorination of COCs, neutral pH and strongly alkaline pH (pH > 12) were studied. It was found that the higher the COCs concentration adsorbed in soil, the higher the adsorption of the surfactants, finding an irreversible adsorption in the case of nonionic surfactants. The desorption of COCs increased with the surfactant concentration in the aqueous phase and was not selective towards any contaminant. Although at neutral pH, higher COC desorption was found with nonionic surfactants, at alkaline pH surfactant the anionic surfactant improved its COCs desorption capacity significantly. Finally, the adsorption of the surfactants was well adjusted to Langmuir, and the apparent partition coefficient predicted the partitioning of COCs between the soil and aqueous phases, which changes with the surfactant concentration in the aqueous solution.Item Acute Toxicity Evaluation of Lindane-Waste Contaminated Soils Treated by Surfactant-Enhanced ISCO(Molecules, 2022) Santos López, Aurora; García Cervilla, Raúl; Checa Fernández, Alicia; Domínguez, Carmen M.; Lorenzo Fernández, DavidThe discharge of lindane wastes in unlined landfills causes groundwater and soil pollution worldwide. The liquid waste generated (a mixture of 28 chlorinated organic compounds, COCs) constitutes a dense non-aqueous phase liquid (DNAPL) that is highly persistent. Although in situ chemical oxidation (ISCO) is effective for degrading organic pollutants, the low COCs solubility requires high reaction times. Simultaneous injection of surfactants and oxidants (S-ISCO) is a promising technology to solve the limitation of ISCO treatment. The current work studies the remediation of highly polluted soil (COCs = 3682 mg/kg) obtained at the Sardas landfill (Sabiñáñigo, Spain) by ISCO and S-ISCO treatments. Special attention is paid to acute soil toxicity before and after the soil treatment. Microtox®, modified Basic Solid-Phase Test (mBSPT) and adapted Organic Solvent Sample Solubilization Test (aOSSST) were used for this scope. Persulfate (PS, 210 mM) activated by alkali (NaOH, 210 mM) was used in both ISCO and S-ISCO runs. A non-ionic and biodegradable surfactant selected in previous work, Emulse®3 (E3, 5, and 10 g/L), was applied in S-ISCO experiments. Runs were performed in soil columns filled with 50 g of polluted soil, with eight pore volumes (Pvs) of the reagents injected and 96 h between successive Pv injections. The total treatment time was 32 days. The results were compared with those corresponding without surfactant (ISCO). After remediation treatments, soils were water-washed, simulating the conditions of groundwater flux in the subsoil. The treatments applied highly reduced soil toxicity (final soil toxicity equivalent to that obtained for non-contaminated soil, mBSPT) and organic extract toxicity (reduction > 95%, aOSSST). Surfactant application did not cause an increase in the toxicity of the treated soil, highlighting its suitability for full-scale applications.Item Simultaneous addition of surfactant and oxidant to remediate a polluted soil with chlorinated organic compounds: Slurry and column experiments(Journal of Environmental Chemical Engineering, 2022) García Cervilla, Raúl; Santos López, Aurora; Romero, Arturo; Lorenzo Fernández, DavidThe inadequate management of wastes associated with chlorinated organic compounds (COCs) has become a huge environmental problem. Surfactant Enhanced In-Situ Chemical Oxidation (S-ISCO) was studied as a successful technique to remediate polluted sites. This work investigated the reaction between an aqueous solution of nonionic surfactant (Emulse-3®) and an oxidant (sodium persulfate activated with NaOH) with a real polluted soil with a complex mixture of COCs from lindane liquid wastes. Two experimental setups were used. In the first one, the reactions were carried out in batch mode under slurry conditions using different surfactant concentrations (0–10 g⋅L− 1), 210 mM of persulfate and 420 mM of NaOH with an aqueous to soil ratio VL/W = 10 L⋅kg− 1. The runs were carried using a column loaded with the soil in the second experimental setup. The solution of surfactant, oxidant and activator was put in contact with soil in four pore volumes with a ratio aqueous to soil ratio VL/W = 0.2 L⋅kg− 1. Under these experimental conditions, the surfactant addition improved the reduction of COCs compared with the application carried out without surfactant, from 40.1% to values of conversion of 64.8 – 90.4%. However, an excess of surfactant hindered the COCs oxidation and increased the unproductive consumption of the oxidant, resulting in an optimal value of surfactant in the aqueous phase (1–2 g⋅L− 1). A remarkable drop in the surfactant concentration in the aqueous phase and COCs solubilized was noticed in column runs due to the surfactant adsorption.- Project number: 334
Item Aprendizaje bidireccional a través de cuestionarios online(2022) Domínguez Torre, Carmen María; Santos López, Aurora; Rodríguez Vega, Sergio; Lorenzo Fernández, David; Cotillas Soriano, Salvador; Conte, Leandro Oscar; Sáez González, Patricia; García Cervilla, Raúl; Checa Fernández, Alicia; Sánchez Yepes, AndrésEl presente proyecto de innovación docente utiliza la herramienta online del Campus Virtual “entorno de cuestionarios” para mejorar la docencia impartida por los profesores, ayudar a los estudiantes a detectar sus puntos débiles (con suficiente antelación a la realización de los exámenes de la asignatura) e incentivar el estudio, autonomía y aprendizaje en Ingeniería de la Reacción Química, asignatura anual y de carácter obligatorio, de tercer curo del Grado de Ingeniería Química. - Project number: 444
Item Herramientas de gamificación para la evaluación de competencias en ingeniería de la reacción Química(2023) Domínguez Torre, Carmen María; Santos López, Aurora; Martínez Rodríguez, Mercedes; Rodríguez Vega, Sergio; Cotillas Soriano, Salvador; Lorenzo Fernández, David; García Cervilla, Raúl; Checa Fernández, Cristina Alicia; Sánchez Yepes, Andrés; Domínguez Torre, Carmen MaríaEl objetivo del proyecto es la utilización de herramientas de gamificación para motivar la participación del estudiante en clase, identificar los conceptos de la asignatura (Ingeniería de la Reacción Química, del Grado en Ingeniería Química) que presentan mayor dificultad de aprendizaje y evaluar los conocimientos adquiridos en clase por parte de los estudiantes. La herramienta seleccionada en el proyecto ha sido Quizziz (https://quizizz.com/?lng=es-ES). Se trata de una herramienta de gamificación que permite evaluar a los estudiantes mientras se divierten. La información obtenida durante el desarrollo del proyecto permitirá, por un lado, detectar los contenidos de la asignatura más difíciles de asimilar y, por otro, actuar sobre la docencia impartida relativa a dichos aspectos. Durante el curso se propondrán una serie de casos prácticos (problemas relacionados con cada tema/bloque de la asignatura), para que el estudiante los resuelva de forma individual, haciendo uso del material que considere oportuno. De esta forma adquirirá autonomía en el empleo de fuentes bibliográficas. El profesor seleccionará uno de los casos propuestos para resolver en el aula durante una parte de la sesión de seminarios. En la segunda parte de la sesión se emplearán herramientas de gamificación para plantear y resolver cuestiones adicionales en relación con el caso práctico resuelto previamente. De este modo, no solo se evaluarán las destrezas de los estudiantes en cuanto a la resolución de problemas se refiere, sino también, su capacidad para poner en práctica los conocimientos teóricos adquiridos ante problemas abiertos. El estudiante conocerá en tiempo real si su respuesta es correcta y podrá identificar las carencias de aprendizaje y reforzar/profundizar en esos conocimientos. La herramienta de gamificación permite fomentar la participación del estudiante en clase y mejorar su aprendizaje. Los profesores pueden identificar si existen aspectos donde se detectan carencias en el conocimiento en un número mayor de estudiantes para mejorar la transmisión del conocimiento en esos puntos. Así, este proyecto de innovación educativa busca fomentar la participación y el aprendizaje continuo del estudiante durante el curso a través de la resolución de casos prácticos y la aplicación de herramientas de gamificación en el aula. Con esta actividad se pretende aumentar la adquisición de conocimientos y competencias y mejorar la tasa de éxito de la asignatura Ingeniería de la Reacción Química. Item Surfactant-Enhanced Solubilization of Chlorinated Organic Compounds Contained in DNAPL from Lindane Waste: Effect of Surfactant Type and pH(International Journal of Environmental Research and Public Health, 2020) García Cervilla, Raúl; Romero, Arturo; Santos López, Aurora; Lorenzo Fernández, DavidApplication of surfactants in the remediation of polluted sites with dense nonaqueous phase liquid (DNAPL) still requires knowledge of partitioning between surfactants and pollutants in the organic and aqueous phases and the time necessary to reach this balance. Two real DNAPLs, generated as wastes in the lindane production and taken from the polluted sites from Sabiñanigo (Spain), were used for investigating the solubilization of 28 chlorinated organic compounds (COCs) applying aqueous surfactant solutions of three nonionic surfactants (E-Mulse® 3 (E3), Tween®80 (T80), and a mixture of Tween®80-Span®80 (TS80)) and an anionic surfactant (sodium dodecyl sulfate (SDS)). The initial concentrations of surfactants were tested within the range of 3–17 g·L −1 . The pH was also modified from 7 to >12. The uptake of nonionic surfactants into the organic phase was higher than the anionic surfactants. Solubilization of COCs with the nonionic surfactants showed similar molar solubilization ratios (MSR = 4.33 mmolCOCs·g −1 surf), higher than SDS (MSR = 0.70 mmolCOCs·g −1 SDS). Furthermore, under strong alkaline conditions, the MSR value of the nonionic surfactants was unchanged, and the MSR of SDS value increased (MSR = 1.32 mmolCOCs·g −1 SDS). The nonionic surfactants did not produce preferential solubilization of COCs; meanwhile, SDS preferentially dissolved the more polar compounds in DNAPL. The time required to reach phase equilibrium was between 24 and 48 h, and this contact time should be assured to optimize the effect of the surfactant injected on COC solubilization.Item Modified SWCNTs with Amphoteric Redox and Solubilizing Properties(Chemistry – A European Journal, 2014) Rodríguez Pérez, Laura; García Cervilla, Raúl; Herranz Astudillo, María Ángeles; Martín León, NazarioA complementary double‐covalent functionalization of single‐wall carbon nanotubes (SWCNTs) that involves both solubilizing ionic liquids and electroactive moieties is reported. Our strategy is a simple and efficient methodology based on the stepwise functionalization of the nanotube surface with two different organic moieties. In a first instance, oxidized SWCNTs are amidated with ionic liquid precursors, and further treated with butyl bromide to afford SWCNTs functionalized with 1‐butylimidazolium bromide. This approach allows tuneable polarity induced by anion exchange, which has an effect on the relative solubility of the modified SWCNTs in water. Subsequently, a 1,3‐dipolar cycloaddition reaction was performed to introduce the electron‐acceptor 11,11,12,12‐tetracyano‐9,10‐anthra‐quinodimethane (TCAQ) unit on the SWCNTs. Furthermore, to evaluate the influence of the functional group position, the TCAQ electroactive molecule was anchored through an esterification reaction onto previously oxidized SWCNTs, followed by the Tour reaction to introduce the ionic liquid functions. IR and Raman spectroscopies, thermogravimetric analysis (TGA), UV/Vis/NIR spectroscopy, transmission electron microscopy (TEM), and X‐ray photoelectron spectroscopy (XPS) were employed and clearly confirmed the double‐covalent functionalization of the SWCNTs.