0000000000194614
AUTHOR
Amparo Cháfer
showing 33 related works from this author
Study of liquid–liquid equilibrium of the systems isobutyl acetate+acetic acid+water and isobutyl alcohol+acetic acid+water at different temperatures
2008
Abstract In this work, experimental liquid–liquid equilibria (LLE) data of the systems isobutyl acetate + acetic acid + water and isobutyl alcohol + acetic acid + water are presented. The liquid–liquid equilibria of both systems have been measured at 283.15 and 323.15 K. The NRTL and UNIQUAC models were applied to fit the data for both ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The experimental tie lines were compared to the values predicted by the UNIFAC method. Moreover, the solvent capabilities of isobutyl acetate and isobutyl alcohol were compared.
Liquid–Liquid Equilibria of Water + Ethanol + 1-Butyl-3-methylimidazolium Bis(trifluoromethanesulfonyl)imide Ternary System: Measurements and Correla…
2015
In this work authors present the experimental liquid–liquid equilibria (LLE) data of water + ethanol + 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([bmim][Tf2N]) system at different temperatures. The LLE of the system was obtained in the temperature range from 283.2 to 323.2 K. The nonrandom two liquid (NRTL) and universal quasichemical (UNIQUAC) models were used to correlate ternary systems. The equilibrium compositions were successfully correlated by the interaction parameters from both models, however UNIQUAC gave a more accurate correlation. Finally, a study about the solvent capability of ionic liquid was made in order to evaluate the possibility of separating the mi…
Measurements and correlation of liquid–liquid equilibria of 4-methyl-2-pentanone+ethanol+water and 4-methyl-2-pentanone+n-butanol+water ternary syste…
2012
Abstract In this work, experimental liquid–liquid equilibria data of the systems 4-methyl-2-pentanone + ethanol + water and 4-methyl-2-pentanone + n-butanol + water are presented. The liquid–liquid equilibria of both systems have been measured between 283.2 and 323.2 K. The NRTL and UNIQUAC models were applied to fit the data for both ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The binodal lines were compared to the values predicted by the UNIFAC-LLE and UNIFAC models. Moreover, the solvent capability of 4-methyl-2-pentanone was checked in order to separate these azeotropic mixtures alcohol + water.
eCity: Virtual City Environment for Engineering Problem Based Learning
2015
The main objective of the eCITY project is to design, develop and validate a pedagogical methodology, supported by an online, collaborative, city-development simulation engine (Simcity like) that stimulates the integration and continuous exploitation of Problem-Based Learning (PBL) in engineering and science schools but, at the same time, fostering the interest for these orientations in secondary school students. DOI: http://dx.doi.org/10.4995/HEAd15.2015.447
Study of liquid–liquid equilibria at different temperatures of water + ethanol + 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide tern…
2016
Abstract The experimental liquid–liquid equilibria (LLE) data of the water + ethanol + 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([bmp][Tf2N]) system has been measured at different temperatures in this work. The LLE of the system has been measured at between 283 and 333 K. The UNIQUAC and NRTL models were used to correlate the LLE data and good results were obtained in both cases, however UNIQUAC gave a more accurate correlation. In order to apply the UNIQUAC model the volume and surface parameters for [bmp][Tf2N] (r, q) were determined. Finally, in order to obtain ethanol from the aqueous mixture, the solvent capability of the ionic liquid was checked and compared wit…
Capability study of 1-butyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide and trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phos…
2018
Abstract The liquid-liquid equilibria of the ternary systems water (1) + 1-propanol (2) + 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf2N]) (3) and water (1) + 1-propanol (2) + trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate ([TDTHP][Phosph]) (3) at 283.2, 303.2 and 323.2 K and atmospheric pressure were determined to study their behaviour, determine their thermodynamic parameters and know the capability as solvents of [bmim][Tf2N] and [TDTHP][Phosph] in the separation of the azeotropic mixture water + 1-propanol. The non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models were used in the calculation of the thermodynamic par…
Study of the capability of 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid as solvent in the separation of water from 1-pr…
2020
Abstract After the good behavior of different 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids (ILs) used as solvents in the separation of 1-propanol and 2-propanol from water, liquid-liquid equilibria data was measured from a system formed by a ternary mixture of water, 1-propanol or 2-propanol and 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([dmim][Tf2N]) at 283.2, 303.2 and 323.2 K and atmospheric pressure. The non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models were employed to obtain the thermodynamic parameters of both ternary mixtures, with good results in all cases. Finally, the capability of [dmim][Tf2N] to separate…
Liquid–liquid equlibria of the system dimethyl carbonate+methanol+water at different temperatures
2006
Abstract In this work, experimental liquid–liquid equilibria (LLE) data of the dimethyl carbonate + methanol + water system are presented. The LLE of this system has been measured from 283 to 333 K. On the other hand, LLE and LVE of the binary system dimethyl carbonate + water have been measured. The equilibrium data presented are correlated using NRTL and UNIQUAC equations. The reliability of these models is tested by comparison with experimental results. Finally, the VLE for the system DMC + water at 101.3 kPa was predicted using the UNIQUAC model, with the adjusted parameters obtained from the LLE data. This prediction was successful when is compared with the experimental VLE data.
Potential of phosphonium-based ionic liquids to purify 1-propanol from water by liquid–liquid extraction at mild conditions
2022
Abstract In order to reduce the environmental of the separation of 1-propanol from water in a residual industry stream for its reuse, the capability as solvents of two different trihexyl(tetradecyl)phosphonium ionic liquids (ILs) – trihexyl(tetradecyl)phosphonium chloride ([TDTHP][Cl]) and trihexyl(tetradecyl)phosphonium bromide ([TDTHP][Br])-, was studied. The liquid–liquid equilibria data for both ternary systems, {water + 1-propanol + [TDTHP][Cl]} and {water + 1-propanol + [TDTHP][Br]} at different mild work temperatures, (283.2, 303.2 and 323.2) K, and atmospheric pressure were measured. The thermodynamic parameters for both ternary systems at different work conditions were obtained by …
Measurements and correlation at different temperatures of liquid–liquid equilibria of 2-butanol or 2-methyl-2-butanol+1,2,3-propanetriol+water ternar…
2014
Abstract In this work, the experimental liquid–liquid equilibria (LLE) data of 2-methyl-2-butanol + 1,2,3-propanetriol (glycerol) + water and 2-butanol + 1,2,3-propanetriol (glycerol) + water systems at different temperatures are presented. The LLE of the systems has been measured between 283 and 323 K. The NRTL and UNIQUAC models were applied to the ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The experimental tie lines were compared to the values predicted by the UNIFAC method. Finally, the solvent capability of both alcohols was checked in order to separate the mixture formed by glycerol and water.
Workshops of innovation in chemical engineering to train communication skills in science and technology
2019
Abstract This paper shows the application of an innovate pedagogical approach based on the project-based learning technique, focused on the training of communication skills in the framework of a workshop of innovation in chemical engineering. Written, graphical verbal, and non-verbal communication were tackled. For that purpose, a project of technological innovation was developed by the students in teams within the specific area of chemical engineering. A professional-like environment was simulated by a final workshop where the students defenced and supported their project by using oral presentation and production of a poster and a video. Several surveys were performed before and after the …
Supercritical fluid extraction of resveratrol from grape skin of Vitis vinifera and determination by HPLC
2000
Supercritical fluid extraction of resveratrol from grape skin of Vitis vinifera was studied. Extraction variables such pressure, modifier concentration (ethanol), and extraction time were optimised. Final extraction conditions were: 40 degrees C, 150 bar, 7.5% ethanol and extraction time 15 min. Extraction recovery and precision (variation coefficient between 0.2 and 1.0%) were calculated. The resveratrol content in the ethanolic extract was determined by HPLC with UV detection at 306 nm. Acetic acid-methanol-water was used as the mobile phase, and C-18 and C-8 columns were tested, instrumental parameters were optimised, and analytical parameters were calculated (lineal interval 0-75 mg l(-…
Study of liquid–liquid extraction of ethanol + water azeotropic mixtures using two imidazolium-based ionic liquids
2018
Abstract The present work was focused on the study of two imidazolium-based ionic liquids (ILs) as solvents in liquid–liquid extraction of ethanol from aqueous mixtures. With this aim, the experimental liquid–liquid equilibria (LLE) data of water (1) + ethanol (2) + 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([emim][Tf2N]) (3) and water (1) + ethanol (2) + 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([hmim][Tf2N]) (4) systems were obtained at different temperatures: 283.2, 303.2, and 323.2 K, in order to check the influence of temperature. The results were correlated by non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models with good c…
Study of separation of water + 2-propanol mixture using different ionic liquids: 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or 1-b…
2018
Abstract The liquid–liquid equilibria data of water (1) + 2-propanol (2) + [bmim][Tf2N] (3) and water (1) + 2-propanol (2) + [bmp][Tf2N] (3) at 283.2, 303.2 and 323.2 K and atmospheric pressure were measured with the objective of understanding the behavior of these two systems and to try to improve the extraction of 2-propanol from water from economical and environmental points of view. The thermodynamic parameters were determined using the non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models, and excellent results were achieved in both cases (the maximum root-mean-square deviation was 0.433%). Lastly, the capability of the two ionic liquids to separate 2-propanol from …
High Pressure Solubility Data of the System Limonene + Linalool + CO2
2001
The feasibility of deterpenating orange peel oil with supercritical CO2 depends on relevant vapor−liquid equilibrium data because the selectivity of this solvent for limonene and linalool (the two key components of the oil) is of crucial importance. In this work the solubility data for the CO2 + limonene + linalool ternary system were measured at (318.2 and 328.2) K. The range of pressures covered was from (70 to 110) bar. Two different mixtures of limonene + linalool were used: a 40 mass % limonene + 60 mass % linalool mixture and a 60 mass % limonene + 40 mass % linalool mixture. To correlate the obtained results, two equations of state were successfully used (Peng−Robinson (PR) and Soav…
High-pressure solubility data of system ethanol (1)+catechin (2)+CO2 (3)
2001
Abstract Supercritical fluid extraction posses several advantages over traditional liquid–solvent-based extraction methods including improved selectivity, expeditiousness, automation and environmental safety. Fluid phase equilibrium data is essential for study the viability of supercritical extraction and the design of the extraction columns often used for this type of separations. During the past few years it has been demonstrated that phenolic compounds, such catechins and procyanidins from seeds, contribute to both the flavour properties and the pharmacological effects of wine. The extraction of catechin using supercritical CO2 is not possible, it only extracts traces of product, probabl…
Liquid–liquid equilibria of the systems dipropyl ether+n-propanol+water and dipropyl ether+n-propanol+ethylene glycol at different temperatures
2007
Abstract In this work, experimental liquid–liquid equilibria (LLE) data of the dipropyl ether + n-propanol + water and dipropyl ether + n-propanol + ethylene glycol systems are presented. The LLE of both systems have been measured at 283.15 and 323.15 K. The equilibrium data presented are correlated using NRTL and UNIQUAC equations. The reliability of these models is tested by comparison with experimental results. Moreover, the solvent capabilities of water and ethylene glycol were compared, concluding that ethylene glycol is the best solvent to extract n-propanol.
Separation of the azeotropic mixture 2-propanol + water employing different imidazolium ionic liquids as solvents
2020
Abstract The liquid-liquid equilibria of the ternary systems water (1) + 2-propanol (2) + [emim][Tf2N] (3) and water (1) + 2-propanol (2) + [hmim][Tf2N] (3) at 283.2, 303.2 and 323.2 K and atmospheric pressure were investigated, in order to achieve a better knowledge of the ternary mixture behaviour. The capability of [emim][Tf2N] and [hmim][Tf2N] as solvents in the separation of the azeotropic mixture water + 2-propanol was studied through the distribution coefficient and selectivity, and compared with the results obtained with other ionic liquids in the same azeotropic mixture studied before by our research group. The thermodynamic parameters of both ternary mixtures were calculated by th…
Liquid–liquid equilibria of 4-methyl-2-pentanone+1-propanol or 2-propanol+water ternary systems: Measurements and correlation at different temperatur…
2014
Abstract In this work, experimental liquid–liquid equilibria data of the systems 4-methyl-2-pentanone + 1-propanol + water and 4-methyl-2-pentanone + 2-propanol + water are presented. The liquid–liquid equilibria of both systems have been measured at 283.2 and 323.2 K. The NRTL and UNIQUAC models were successfully applied to fit the data for both ternary systems. The binodal lines were compared to the values predicted by the UNIFAC-LLE and UNIFAC models. Moreover, the solvent capability of 4-methyl-2-pentanone was checked in order to separate the azeotropic mixtures formed by propanol's and water.
Liquid–liquid equilibria of the systems isobutyl acetate+isobutyl alcohol+water and isobutyl acetate+isobutyl alcohol+glycerol at different temperatu…
2008
Abstract In this work, experimental liquid–liquid equilibria (LLE) data of the isobutyl acetate + isobutyl alcohol + water and isobutyl acetate + isobutyl alcohol + glycerol systems are presented. The LLE of both systems have been measured at 283.15 and 323.15 K. The NRTL and UNIQUAC models were applied to both ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The experimental tie lines were compared to the values predicted by the UNIFAC method. Moreover, the solvent capabilities of water and glycerol were compared.
Measurement and correlation of liquid-liquid equilibria at different temperatures in water + 1-propanol + 1-ethyl-3-methylimidazolium bis(trifluorome…
2016
Abstract In order to reduce the environmental impact and the economical costs of the separation of 1-propanol from aqueous mixtures, which enables the recycling of the alcohol, the experimental liquid-liquid equilibria (LLE) data of water (1) + 1-propanol (2) + 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([emim][Tf2N]) (3) and water (1) + 1-propanol (2) + 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([hmim][Tf2N]) (3) systems were measured in this work at different temperatures: 283.2, 303.2 and 323.2 K at atmospheric pressure. The results were correlated by non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models with good results in both…
High-pressure solubility data of the system resveratrol (3)+ethanol (2)+CO2 (1)
2001
Abstract Supercritical fluid extraction possesses several advantages over traditional liquid-solvent-based extraction methods, including improved selectivity, expeditiousness, automation and environmental safety. Fluid-phase equilibrium data are essential for studying the viability of supercritical extraction and the design of the extraction columns often used for this type of separation. Resveratrol has been correlated with serum lipid reduction and inhibition of platelet aggregation, and its cancer chemopreventive activity has recently been reported. The extraction of resveratrol using supercritical CO 2 is not possible; it only extracts traces of product, probably due to its polar nature…
Liquid–liquid equlibria of the mixture linalool+ethanol+water at different temperatures
2005
Abstract In this work, experimental liquid–liquid equilibria (LLE) data of the linalool + ethanol + water system are presented. The LLE of this system has been measured at 293.15, 303.15, 313.15 and 323.15 K. The equilibrium data presented are correlated using NRTL and UNIQUAC equations. Finally, the reliability of these models is tested by comparison with experimental results.
The influence of the temperature on the liquid–liquid equlibria of the mixture limonene + ethanol + H2O
2004
Abstract In this work, experimental liquid–liquid equilibria (LLE) of the limonene + ethanol + water system are presented. The LLE of this system has been measured at 293.15, 303.15, 313.15 and 323.15 K. The equilibrium data presented are correlated using NRTL and UNIQUAC equations. Finally, the reliability of these models is tested by comparison with experimental results.
Study of kinetics of the d-pinitol extraction from carob pods using supercritical CO2
2014
Abstract There is a growing interest in the use of d -pinitol ( d -3-O-methyl-chiro-inositol) as a food supplement, thus the use of green and efficient process, such as the supercritical fluid extraction (SFE), to isolate d -pinitol from vegetable raw materials is also an interesting area of research and development. The objective of this work was to study the influence of operating conditions on the SFE of d -pinitol from carob pods. The crucial parameters in SFE, like temperature, pressure, CO 2 flow rate and duration of the process, have been studied. Finally, Naik and Barton models have successfully tested in order to fit the experimental extraction curves.
Supercritical fluid extraction and HPLC determination of relevant polyphenolic compounds in grape skin.
2005
The polyphenols determined are: (+)-catechin, (-)-epicatechin, rutin, quercetin and trans-resveratrol. Suitable conditions of supercritical fluid extraction were established using ethanol as a modifier of the polarity solvent (supercritical carbon dioxide). Final extraction conditions were: 20% v/v ethanol, 60degreesC, 250 bars and flow rate 2 mL/min. Static step time and dynamic step time were established using a selected grape skin sample. The extract was collected in water; the more polar polyphenols ((+)-catechin and (-)-epicatechin) remain in solution but rutin, quercetin and trans-resveratrol precipitate in this medium, thereby the solution of the extracted polyphenols was filtered. (…
Solubility of solid carnosic acid in supercritical CO2 with ethanol as a co-solvent
2005
Abstract The present study is devoted to the experimental measurement and thermodynamic modeling of solid carnosic acid solubility in supercritical CO 2 + ethanol as a co-solvent. Measurements were carried out at temperatures in the range of 313.15 and 333.15 K, pressures ranging from 280 to 400 bar, and at different content of the modifier ethanol (from 0.7 to 10%). The Group Contribution Associating Equation of State (GCA-EoS) [H.P. Gros, S.B. Bottini, E.A. Brignole, High pressure phase equilibrium modeling of mixtures containing associating compounds and gases, Fluid Phase Equilibria 139 (1997) 75–87] was applied in this work to represent the experimental solubility data obtained. Due t…
Liquid−Liquid Equilibria for the System 1-Methyl Propyl Ethanoate (1) + Acetic Acid (2) + Water (3) at (283.15 and 323.15) K
2009
Liquid−liquid equilibrium (LLE) data for the system 1-methyl propyl ethanoate + acetic acid + water were measured at temperatures of (283.15 and 323.15) K. The temperature influence on the LLE data is very small in the temperature range studied. The NRTL and UNIQUAC models were used to correlate the data for both ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions.
Solubility of quercetin in supercritical CO2 + ethanol as a modifier: measurements and thermodynamic modelling
2004
Abstract Grape seeds extracts have shown a broad range of pharmacological activities including, among others, antiulcer and antioxidant properties, which are mainly attributed to the phenolic compounds present. To date, the most abundant phenolic compounds isolated from grape seeds are catechins and their derivatives, e.g. quercetin. The present study is devoted to the experimental measurement and thermodynamic modelling of the solubility of quercetin in supercritical CO 2 + ethanol as a co-solvent. The solubility of quercetin was measured at 313.15 K, pressures ranging from 80 to 120 bar, and at different content of the modifier ethanol—from 5 to 30%. Two types of thermodynamic models were…
Experimental Determination and Correlation of Liquid–Liquid Equilibria Data for a System of Water + Ethanol + 1-Butyl-3-methylimidazolium Hexafluorop…
2017
Over the past few years, interest has increased regarding the application of ionic liquids (ILs) as extraction solvents for separating azeotropic mixtures. Following this trend, this work presents the experimental data of liquid–liquid equilibria (LLE) of the system envolving water, ethanol, and 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) at different temperatures. The LLE data of the system was measured between 283.2 and 323.2 K to determine the temperature influence on the system. In the literature, reports of systems involving ILs that present type II behavior are scarce compared with those that present type I behavior; the system presented here also displays two immisc…
Liquid–Liquid Equilibria of the Water + 1-Propanol + 1-Butyl-1-methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide Ternary System: Study of the Abi…
2016
An important problem in the chemical industry is the separation of azeotropes. Their separation by simple distillation is basically impossible, and extractive distillation consumes much more energy than liquid–liquid extraction, so this alternative could be interesting. Recently, researchers have started to explore these option using ionic liquids as the solvent. The remarkable properties of ionic liquids have made them sustainable alternatives to conventional solvents. This work is a continuation of a study developed by our research group on the use of ionic liquids as extractant solvents of alcohol + water mixtures which form azeotropes, using in this case 1-butyl-1-methylpyrrolidinium bi…
Lectura en barómetro
2012
Elaboración de material digital y recursos en la red para el tercer curso de la titulación de Química y nuevos grados. El objetivo de este vídeo es aprender a medir la presión atmosférica en un barómetro.
Mediciones con pie de rey
2012
Elaboración de material digital y recursos en la red para el tercer curso de la titulación de Química y nuevos grados. El objetivo de este vídeo es aprender a medir longitudes utilizando el pie de rey o calibre, instrumento de medida basado en el nonius.