Desalination using modified configuration of supported liquid membrane with enhancement of mass transfer of NaCl

Abstract Supported liquid membranes (SLM) suffer from very slow mass transfer of the solute from the donor phase (DP) to the receptor phase (RP) through the liquid membrane (LM). In the present work, an attempt was made to accelerate the mass transfer in SLM by creating a modified configuration in which the DP and RP are made to flow either co- or counter-currently to each other. Variables, which could affect the removal of NaCl, were the volume ratio of DP to RP, type and quantity of sequestering agent (SA), presence of mobile carrier (MC), type of LM, and flow rate of DP and RP. The results showed that the higher the flow rate of DP and RP, the higher the mass transfer of NaCl. Quantity and type of SA and type of LM were prime important factors. Remarkably, the time required for transfer of NaCl from DP to RP was reduced from several hours in the case of stagnant SLM to several minutes in the present work. The mass transfer of NaCl was analysed based on kinetic laws of two consecutive irreversible first-order reactions. The values achieved establish the process is diffusion controlled, and the membrane entrance rate constants increase directly with initial concentration (Ci) and inversely with quantity of SA.

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Emulsion Liquid Membrane for Cadmium Removal: Experimental Results and Model Prediction

Jurnal Teknologi ◽

10.11113/jt.v65.2321 ◽

2013 ◽

Vol 65 (4) ◽

Cited By ~ 1

Author(s):

A. L. Ahmad ◽

Adhi Kusumastuti ◽

M. M. H. Shah Buddin ◽

D. C. J. Derek ◽

B. S. Ooi

Keyword(s):

Mass Transfer ◽

Model Prediction ◽

Liquid Membrane ◽

Volume Ratio ◽

Membrane System ◽

Extraction Process ◽

Transfer Model ◽

Emulsion Liquid Membrane ◽

Cadmium Removal ◽

External Phase

A study on mass transfer model for cadmium extraction in emulsion liquid membrane system has been done. Mass transfer in the external phase and emulsion globule, stripping reaction, and diffusion of the complex were taken account into the model. Reaction and chemical equilibrium of the process were also considered. The partial differential equation was numerically solved using MATLAB software. Effect of some parameters such as acid concentration in the external phase, extraction speed, volume ratio of emulsion to feed phase, volume ratio of internal to membrane phase, and initial concentration to the extraction process were investigated and compared to the model. The model prediction can agree very well with the concentration profile of cadmium in each phase.

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Effect of viscosity of a liquid membrane containing oleyl alcohol on the pertraction of butyric acid

Chemical Papers ◽

10.2478/s11696-013-0370-4 ◽

2013 ◽

Vol 67 (12) ◽

Cited By ~ 6

Author(s):

Marek Blahušiak ◽

Ján Marták ◽

Fernando Miranda ◽

Štefan Schlosser ◽

José Teixeira

Keyword(s):

Mass Transfer ◽

Butyric Acid ◽

Driving Force ◽

Oleyl Alcohol ◽

Liquid Membrane ◽

High Viscosity ◽

Membrane Extraction ◽

Low Viscosity ◽

Supported Liquid Membranes ◽

The Relationship

AbstractSolvent formulation is important in the optimization of the mass-transfer through supported liquid membranes (SLM) in pertraction and membrane extraction. Oleyl alcohol (OA) is frequently used as the solvent or diluent in the extraction of carboxylic acids. A disadvantage of OA is its relatively high viscosity of 28.32 mPa s at 25°C. This can be decreased by the application of a less viscous OA diluent, e.g. dodecane. The relationship between the ratio of the distribution coefficient of butyric acid (BA), D F, and the viscosity of OA-dodecane solvents, µ, as extraction and transport characteristics, and the overall mass-transfer coefficient, K p, through SLMs was analyzed. Dependence of the D F/µ ratio on the OA concentration showed a maximum at the OA concentration of 15 mass % to 30 mass %. The OA concentration dependence of K p for SLMs exhibited also a maximum at about 30 mass % and 20 mass % of OA at the BA concentration driving force of 0.12 kmol m−3 and 0.3 kmol m−3, respectively. Shifting of the maximum in K p dependences towards lower OA concentrations by increasing the BA concentration driving force is in agreement with the D F/µ ratio dependence. Using pure OA as the solvent or diluent is not preferable and a mixture of a low viscosity diluent with the OA concentration below 40 mass % should be used. The presented results show the potential of the D F/µ ratio in the screening and formulation of solvents in extraction and SLM optimization.

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Study of cyanide wastewater treatment by dispersion supported liquid membrane using trioctylamine and kerosene as liquid membrane

Water Science & Technology ◽

10.2166/wst.2015.225 ◽

2015 ◽

Vol 72 (4) ◽

pp. 643-650 ◽

Cited By ~ 1

Author(s):

Guo Ping Li ◽

Juan Qin Xue ◽

Li Hua Yu ◽

Ni Na Liu

Keyword(s):

Mass Transfer ◽

Carrier Concentration ◽

Liquid Membrane ◽

Removal Rate ◽

Mass Transfer Rate ◽

Phase Interface ◽

Volume Ratio ◽

Supported Liquid Membrane ◽

Diffusion Layer Thickness ◽

Feed Phase

A certain amount of cyanide is present in wastewater of various industrial processes, such as wet extraction of gold, coal processing, electroplating and other industries. In this work, an experimental study regarding transport of cyanide through a dispersion supported liquid membrane was performed. A model was established to describe the reaction and transport of CN(I) in the supported liquid membrane and the mass transfer kinetics equations were deduced. Through mass transfer kinetic equation it was derived that, when the carrier concentration was under certain conditions, there was a linear relationship between the reciprocal of the permeability coefficient of CN(I) (1/Pc) and n-th power of the concentration of H+ (cnH+), and the parameters Δa(δa/da) and Δo(δ0/d0) could be obtained from the slope and intercept of the straight line. Then the diffusion coefficient do and the diffusion layer thickness δo of the phase interface between the feed phase and membrane phase could be calculated. Factors affecting migration of CN(I) were analyzed, and the stable removal rate of CN(I) was more than 90% with carrier concentration (%TOA) of 2%, feed phase pH of 4, initial CN(I) concentration of 30 mg/L, stirring time of 1 hour, volume ratio of membrane solution to NaOH solution of 2:1, strip phase concentration of 2 mol/L. The results showed that the overall mass transfer rate increased first and then decreased with an increase of TOA concentration, organic-to-strip volume ratio, and strip concentration. Furthermore, the transport percentage of CN(I) was increased, the stability of membrane was enhanced, and the lifetime of the membrane was extended.

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Iono-molecular Separation with Composite Membranes VI. Nitro-phenol separation through sulfonated polyether ether ketone on capillary polypropylene membranes

Revista de Chimie ◽

10.37358/rc.18.7.6379 ◽

2018 ◽

Vol 69 (7) ◽

pp. 1603-1607

Author(s):

Ion Spiridon Din ◽

Anca Maria Cimbru ◽

Abbas Abdul Kadhim Klaif Rikabi ◽

Szidonia Katalin Tanczos ◽

Simona Ticu (Cotorcea) ◽

...

Keyword(s):

Flow Rate ◽

Water Solubility ◽

Composite Membranes ◽

Membrane System ◽

Polyether Ether Ketone ◽

Molecular Separation ◽

Capillary Membrane ◽

Sulfonated Polyether Ether Ketone ◽

Source Phase ◽

Receptor Phase

The importance of removing and / or separating nitro phenols from aqueous solutions through membranes is substantiated by the multitude of recent research in the field, which broadly justifies both the economic and ecological reasons of such an approach. The present paper outlines the results of the transfer of nitro phenols through a membrane system made up of PPET impregnated polypropylene capillaries (PP) impregnated with sulfonate polyetheretherketone (SPEEK). The experiments were carried out in a PP-SPEEK capillary membrane module, with a useful size of 1 m2. Determinations made by using a 4 L / min flow rate source at a 5 mg / l nitrophenol concentration and pH 5 or pH 7, and the pH 12 receiving phase and a flow rate of 0.3 L / min, revealed that o- and p-nitrophenol were transferred much faster than m-nitrophenol (the flux is nearly double); the source phase of the system is concentrated in m-nitrophenol, and the receptor phase in o- and p-nitro phenols; the transfer data correlates with the higher water solubility of m-nitrophenol; mono nitro phenols transfer much faster than di nitrophenol, but both the mono and di nitrophenol streams decrease over time; after 4-5 hours of work, the mono nitrophenol concentration triples in the receiving phase, while the 2,4-dinitrophenol concentration doubles in the source phase.

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Interfacial mass transfer in turbulent flow accompanied by irreversible first order chemical reaction

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19791388 ◽

1979 ◽

Vol 44 (5) ◽

pp. 1388-1396

Author(s):

Václav Kolář ◽

Zdeněk Brož

Keyword(s):

Mass Transfer ◽

Turbulent Flow ◽

Chemical Reaction ◽

Experimental Results ◽

Theoretical Concepts ◽

First Order ◽

Order Chemical Reaction ◽

Interfacial Mass Transfer ◽

First Order Chemical Reaction

Relations describing the mass transfer accompanied by an irreversible first order chemical reaction are derived, based on the formerly published general theoretical concepts of interfacial mass transfer. These relations are compared with experimental results taken from literature.

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Absorption of oxygen into solutions of polymers

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862127 ◽

1986 ◽

Vol 51 (10) ◽

pp. 2127-2134 ◽

Cited By ~ 1

Author(s):

František Potůček ◽

Jiří Stejskal

Keyword(s):

Mass Transfer ◽

Aqueous Solutions ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Flow Rate ◽

Liquid Flow ◽

Flow Curve ◽

Liquid Flow Rate ◽

Polymer Concentration ◽

Newtonian Liquids

Absorption of oxygen into water and aqueous solutions of poly(acrylamides) was studied in an absorber with a wetted sphere. The effects of changes in the liquid flow rate and the polymer concentration on the liquid side mass transfer coefficient were examined. The results are expressed by correlations between dimensionless criteria modified for non-Newtonian liquids whose flow curve can be described by the Ostwald-de Waele model.

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Influence of the Porosity of Polymer Foams on the Performances of Capacitive Flexible Pressure Sensors

Sensors ◽

10.3390/s19091968 ◽

2019 ◽

Vol 19 (9) ◽

pp. 1968 ◽

Cited By ~ 11

Author(s):

Sylvie Bilent ◽

Thi Hong Nhung Dinh ◽

Emile Martincic ◽

Pierre-Yves Joubert

Keyword(s):

Experimental Data ◽

Linear Model ◽

Dielectric Material ◽

Pressure Sensors ◽

Volume Ratio ◽

Measurement Range ◽

Polymer Foams ◽

First Order ◽

Non Linear ◽

Flexible Pressure Sensors

This paper reports on the study of microporous polydimethylsiloxane (PDMS) foams as a highly deformable dielectric material used in the composition of flexible capacitive pressure sensors dedicated to wearable use. A fabrication process allowing the porosity of the foams to be adjusted was proposed and the fabricated foams were characterized. Then, elementary capacitive pressure sensors (15 × 15 mm2 square shaped electrodes) were elaborated with fabricated foams (5 mm or 10 mm thick) and were electromechanically characterized. Since the sensor responses under load are strongly non-linear, a behavioral non-linear model (first order exponential) was proposed, adjusted to the experimental data, and used to objectively estimate the sensor performances in terms of sensitivity and measurement range. The main conclusions of this study are that the porosity of the PDMS foams can be adjusted through the sugar:PDMS volume ratio and the size of sugar crystals used to fabricate the foams. Additionally, the porosity of the foams significantly modified the sensor performances. Indeed, compared to bulk PDMS sensors of the same size, the sensitivity of porous PDMS sensors could be multiplied by a factor up to 100 (the sensitivity is 0.14 %.kPa−1 for a bulk PDMS sensor and up to 13.7 %.kPa−1 for a porous PDMS sensor of the same dimensions), while the measurement range was reduced from a factor of 2 to 3 (from 594 kPa for a bulk PDMS sensor down to between 255 and 177 kPa for a PDMS foam sensor of the same dimensions, according to the porosity). This study opens the way to the design and fabrication of wearable flexible pressure sensors with adjustable performances through the control of the porosity of the fabricated PDMS foams.

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A Numerical Study of Sub-Millisecond Integrated Mix-and-Inject Microfluidic Devices for Sample Delivery at Synchrotron and XFELs

Applied Sciences ◽

10.3390/app11083404 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3404

Author(s):

Majid Hejazian ◽

Eugeniu Balaur ◽

Brian Abbey

Keyword(s):

Molecular Dynamics ◽

Flow Rate ◽

Numerical Study ◽

Three Dimensional ◽

Microfluidic Devices ◽

Liquid Jets ◽

Mixing Efficiency ◽

X Ray Diffraction ◽

Cross Sectional ◽

Time Required

Microfluidic devices which integrate both rapid mixing and liquid jetting for sample delivery are an emerging solution for studying molecular dynamics via X-ray diffraction. Here we use finite element modelling to investigate the efficiency and time-resolution achievable using microfluidic mixers within the parameter range required for producing stable liquid jets. Three-dimensional simulations, validated by experimental data, are used to determine the velocity and concentration distribution within these devices. The results show that by adopting a serpentine geometry, it is possible to induce chaotic mixing, which effectively reduces the time required to achieve a homogeneous mixture for sample delivery. Further, we investigate the effect of flow rate and the mixer microchannel size on the mixing efficiency and minimum time required for complete mixing of the two solutions whilst maintaining a stable jet. In general, we find that the smaller the cross-sectional area of the mixer microchannel, the shorter the time needed to achieve homogeneous mixing for a given flow rate. The results of these simulations will form the basis for optimised designs enabling the study of molecular dynamics occurring on millisecond timescales using integrated mix-and-inject microfluidic devices.

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