Search results for "Distillation"
showing 10 items of 184 documents
Using 1-Ethyl-3-methylimidazolium Trifluoromethanesulfonate as an Entrainer for the Extractive Distillation of Ethanol + Water Mixtures
2009
Isobaric vapor−liquid equilibria (VLE) for the ethanol + water + [emim][triflate] ternary system have been obtained at 100 kPa using a recirculating still. The ethanol + water binary system was also obtained. Furthermore, data were simulated with the Mock’s electrolyte nonrandom two-liquid (NRTL) model, using the solvent−solvent interaction parameters obtained from VLE data of the ethanol + water system and taking the solvent−ionic liquid (IL) interaction parameters for the other binary systems from previous works. The agreement between experimental and calculated data is very good, showing the predictive capacity of the model. The addition of [emim][triflate] produces the disappearance of …
Ionic Liquids as Entrainers in Extractive Distillation: Isobaric Vapor−Liquid Equilibria for Acetone + Methanol + 1-Ethyl-3-methylimidazolium Triflu…
2006
Isobaric vapor−liquid equilibria for the binary systems acetone + methanol, acetone + 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([emim][triflate]), and methanol + [emim][triflate] as well as the vapor−liquid equilibrium for the acetone + methanol + [emim][triflate] ternary system have been obtained at 100 kPa using a recirculating still. The addition of the ionic liquid to the solvent mixture produced an important salting-out effect, and the azeotrope tended to disappear for small contents of ionic liquid. The experimental binary data sets were independently fitted with the electrolyte NRTL model, and the parameters of Mock's model were estimated for each binary system. These pa…
An ultrathin suspended hydrophobic porous membrane for high-efficiency water desalination
2017
Abstract An ultrathin highly fluorinated porous membrane was designed for a large production of desalted water at very low energy consumption. Imprinting water droplets were used through a low thermally conductive tetra-fluoroethylene (TFE)/2,2,4-trifluoro-5-tri-fluorometoxy-1,3-dioxol (TIT) (HYFLON AD 60) solution and the generated porous nanofilm was suspended onto a polyethersulfone (PES) honeycomb texture. The very tiny fluorinated thickness together with a large number of small-shaped pores provided the membrane for enhanced anti-wetting surface properties, extremely reduced resistance to water vapor transfer and outstanding thermal efficiency. Fine materials structure-transport relati…
CFD simulation of a membrane distillation module channel
2009
The interest towards the use of membrane distillation (MD) processes for seawater desalination has been rising recently due to the ease of coupling MD with waste and/or solar thermal energy. Notwithstanding the flexibility of the process and its potential for further developments in membrane performances, one of the main drawbacks is the thermal efficiency reduction caused by temperature polarization. Because of such phenomenon, only a small amount of the driving force potentially available for the separation process, i.e. the temperature difference between evaporating and condensing fluids, is actually used for the separation. In order to reduce temperature polarization a study on the effe…
Composition of essential oil of lemon thyme (Thymus × citriodorus) at different hydrodistillation times.
2018
Distillation time can both to optimise the production and to engineer the composition of essential oil in essential oil bearing plants. Purpose of this study was to evaluate the effect of duration of hydrodistillation on composition of essential oil of Thymus × citriodorus, the natural source of commercially important geraniol and citral, a component with valuable biological properties. Essential oils were isolated by hydrodistillation at different distillation times and analysed by GC/MS analytical methods. Increase in percentage of essential oil during all hydrodistillation time gradient was uneven. Elongation of hydrodistillation time decreased percentages of monoterpenes but increased p…
Evaluation of Diethyl Carbonate and Methyl Isobutyl Ketone as Entrainers for the Separation of 1-Hexene and n-Hexane
2017
Diethyl carbonate and methyl isobutyl ketone are tested as possible entrainers for separating 1-hexene and n-hexane by extractive distillation. For this purpose, isobaric vapor–liquid equilibrium (VLE) data at 100 kPa have been obtained for the two ternary systems formed by the two hydrocarbons and one of the selected solvents: 1-hexene + n-hexane + diethyl carbonate and 1-hexene + n-hexane + methyl isobutyl ketone. VLE data for the following constituent binary systems have also been determined: 1-hexene + diethyl carbonate, n-hexane + diethyl carbonate, 1-hexene + methyl isobutyl ketone, and finally n-hexane + methyl isobutyl ketone. All binary systems present moderate positive deviations …
Azeotropic distillation for 1-propanol dehydration with diisopropyl ether as entrainer: Equilibrium data and process simulation
2019
Abstract Azeotropic distillation process is widely used to separate non-ideal binary mixtures into their constituent pure components. 1-Propanol dehydration was used as case study and diisopropyl ether was analysed as possible entrainer in an azeotropic distillation. The separation of some alcohols from their aqueous solution is a challenging task because these aqueous mixture forms minimum boiling azeotrope. In this way, isobaric vapor-liquid and vapour-liquid-liquid equilibrium data were measured for the 1-propanol+ water + diisopropyl ether ternary mixture at 101.3 kPa. The data were correlated by NRTL and UNIQUAC models. A separation sequence (a decanter and a single-feed distillation c…
Separation of di-n-propyl ether and n-propyl alcohol by extractive distillation and pressure-swing distillation: Computer simulation and economic opt…
2011
Abstract Azeotropic mixtures are impossible to separate by ordinary distillation. Two of the most common methods for separating a binary homogeneous azeotrope are pressure-swing distillation (PSD) and extractive distillation (ED). The PSD process is effective if the azeotropic composition changes significantly with pressure. The ED process is effective if a suitable solvent can be found. This paper compares these two alternatives to separate a mixture made up of 50 mol% of di-n-propyl ether and 50 mol% of n-propyl alcohol by means of a practical case of a plant to treat 12,000 Tm/year of this mixture. The simulation has been carried out satisfactorily by mean of a package of commercial soft…
Phase equilibria for the ternary systems ethanol, water+ethylene glycol or+glycerol at 101.3kPa
2013
Abstract Two solvents, ethylene glycol and glycerol, are proposed as possible entrainers for the extractive distillation of the binary azeotropic mixture formed by ethanol and water. In this way, consistent isobaric vapour–liquid equilibrium data at 101.3 kPa were measured for the ternary systems ethanol + water + ethylene glycol and ethanol + water + glycerol. The data were correlated by local compositions models Wilson, NRTL and UNIQUAC. Parameters of these models were later employed to evaluate ability of the candidates to break the original azeotrope. The obtained results led to consider the ethylene glycol and the glycerol as valid entrainers for the extractive distillation process of …
Approach to the 1-propanol dehydration using an extractive distillation process with ethylene glycol
2015
Abstract The extractive distillation process exploits the capacity of some chemicals to alter the relative volatility between the components of a mixture. In this way, a third component (called entrainer) may be added to an azeotropic binary mixture to break the azeotrope. This paper discusses the potential use of ethylene glycol as entrainer in a 1-propanol dehydration process by extractive distillation. First, the present work focuses on the acquisition of isobaric vapor–liquid equilibrium data of the ternary system 1-propanol + water + ethylene glycol system and the binaries systems 1-propanol + ethylene glycol and water + ethylene glycol. All measurements were done at 101.3 kPa. The exp…