Feed Phase Concentration Research Articles

Characterization of a supported ionic liquid membrane used for the removal of cyanide from wastewater.

This work evaluated the performance of ionic liquids (ILs) in supported liquid membranes in the removal of total cyanide from wastewater. Membranes were characterized by scanning electron microscopy and contact angle measurements to study the membrane morphology and wetting ability. In particular, the effects of operational parameters such as membrane immersion time, feed-phase concentration, and pH on cyanide removal were investigated. ILs are organic salts that are entirely composed of organic cations and either organic or inorganic anions. Since their vapor pressure is negligible, they can be handled easily; this characteristic gives rise to their 'green' nature. In this study, a hydrophobic IL, 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim]PF6), was immobilized in the pores of a solid polymeric support made of polyvinylidene fluoride. The optimal conditions were as follows: 1 hour membrane immersion time, 312.24 mg/L feed-phase concentration, a feed-phase pH of 4, 3% NaOH solution, and 1 hour stirring time. The cyanide removal was 95.31%. The treatment of cyanide using supported ionic liquid membrane (SILM) technology is a method with potential applications in industry.

Evaluation of Kinetic Parameters at the Transport of Indole-3-acetic Acid Through Bulk Liquid Membranes

Indole-3-acetic acid is a growth phytohormone considered the most important representative of auxin class. This paper presents the assessment of some kinetic parameters in the process of transport of indole-3-acetic acid taking into consideration the kinetic model of consecutive irreversible first order reactions. It was pursued the influence upon the process of parameters such as: feed phase concentration, stripping phase concentration in the presence of two type carriers: tributyl phosphate (TBP) and trioctylphosphine oxide (TOPO). Depending on these transport parameters were calculated kinetics parameters such as: pseudo-first-order apparent membrane entrance and exit rate constants, the maximum flux at the entrance and exit out of the membrane. The highest values of the transport flux is obtained in the presence of carrier trioctylphosphine oxide (TOPO) at the concentration in the feed phase of 10-4 mol/L indole-3-acetic acid and a concentration of 10--2mol/L NaOH in the stripping phase.

Transport and selectivity of indium through polymer inclusion membrane in hydrochloric acid medium

In the present paper, a polymer inclusion membrane (PIM) containing polyvinyl chloride (PVC), and bis-(2-ethylhexyl) phosphate (D2EHPA) which was used as extracting agent was used for the recovery of In(III) ions in hydrochloric acid medium. The effects of carrier concentration, feed phase pH, strip phase HCl concentration, temperature on the transport, and the membrane’s stability and thickness were examined. And the conditions for the selective separation of In(III) and Cu(II) were optimized. The results showed that the transport of In(III) across PIM was consistent with the first order kinetics equation, and also it was controlled by both the diffusion of the metal complex in the membrane and the chemical reaction at the interface of the boundary layers. The transport flux (J 0) was inversely proportional to the membrane thickness, however, the transport stability improved as the membrane thickness increased. The transport flux of In(III) and Cu(II) was decreased by excessive acidity of feed phase and high concentration of Cl–. The selectivity separation coefficient of In(III)/Cu(II) was up to 34.33 when the original concentration of both In(III) and Cu(II) was 80 mg∙L–1 as well as the pH of the feed phase and the concentration of Cl– in the adjusting context were0.6 and 0.5 mol∙L–1, respectively.Within the range of pH = 1–3, the separation selectivity of In(III)/Cu(II) reached the peak in the case when the Cl– concentration was 0.7 mol∙L–1.

SEPARATION OF CHROM (VI) FROM ELECTROPLATING WASTE USING POLYMER INCLUSION MEMBRANE (PIM) METHOD

<p><span lang="EN-US">Research of chromium (VI) separation has been done using </span><span lang="EN-US">p</span><span lang="EN-US">olymer </span><span lang="EN-US">i</span><span lang="EN-US">nclusion </span><span lang="EN-US">m</span><span lang="EN-US">embrane (PIM) method. This study aims to generate PIM, separate the metal ion chromium (VI) using PIM and determine the effect of the concentration of the feed phase, the thickness of the membrane and the amount of usage of the membrane for ion chromium (VI) diffusion.</span><span lang="EN-US">Polymer </span><span lang="EN-US">i</span><span lang="EN-US">nclusion </span><span lang="EN-US">m</span><span lang="EN-US">embrane (PIM) was made by mixing Aliquat 336-TBP as carrier compounds, PVC as the base polymer, DBE as a plasticizer and THF as a solvent. PIM membrane was placed between the source of analyte as a feed phase and result of the separation as a receiver phase. Feed phase was electroplating waste metal containing chromium (VI) at pH 4, while the receiver phase was a 2 N NaCl solution with a pH 6.7. </span>The change of v<span lang="EN-US">ariable</span>s<span lang="EN-US"> in this study </span>were<span lang="EN-US"> the concentration of the feed phase </span>at various dilution i.e.,<span lang="EN-US"> 100x, 50x and 10x, the thickness of the membrane i.e., 25 μm, 20 μm and 10 μm</span>,<span lang="EN-US"> and the </span>time of <span lang="EN-US">membrane</span> using i.e.,<span lang="EN-US"> 1, 2 and 3 times. The concentration of chromium (VI) diffused after separation process </span>was<span lang="EN-US"> analyzed </span>by <span lang="EN-US">a</span><span lang="EN-US">tomic </span><span lang="EN-US">a</span><span lang="EN-US">bsorption </span><span lang="EN-US">s</span><span lang="EN-US">pectroscopy (AAS). </span>T<span lang="EN-US">he stability of membrane was observed </span>by analyzing the presence of<span lang="EN-US"> membrane</span>’s<span lang="EN-US"> component </span>in the<span lang="EN-US"> feed</span> phase<span lang="EN-US"> and </span>in the <span lang="EN-US">receiver phase</span>. The analysis was conducted by UV-Vis <span lang="EN-US">spectrophotometry</span>. Meanwhile, s<span lang="EN-US">canning </span><span lang="EN-US">e</span><span lang="EN-US">lectron </span><span lang="EN-US">m</span><span lang="EN-US">icroscopy (SEM) </span>analysis was used <span lang="EN-US">to determine the morphology of membrane surface.</span><span lang="EN-US">The results showed that the chromium ion concentration </span>diffused<span lang="EN-US"> from the feed phase was 99.24</span><span lang="EN-US">%</span>, mean<span lang="EN-US">while the 85.88</span><span lang="EN-US">%</span> of it diffused to the receiving phase<span lang="EN-US">. The highest Cr(VI)</span> ions<span lang="EN-US"> diffus</span>ion was occured at<span lang="EN-US"> the first use of PIM membrane with a thickness of 10 μm and the concentration of the feed phase</span> was<span lang="EN-US"> 10.55 ppm</span> (resulted from 100 times dilution)<span lang="EN-US">. </span>Therefore, i<span lang="EN-US">t can be concluded that the diffusion of chromium (VI) ion was influenced by the concentration of feed phase, the thickness of membrane and </span>the number of membrane application<span lang="EN-US">.</span></p>

SEPARATION OF CHROM (VI) FROM ELECTROPLATING WASTE USING POLYMER INCLUSION MEMBRANE (PIM) METHOD

<p><span lang="EN-US">Research of chromium (VI) separation has been done using </span><span lang="EN-US">p</span><span lang="EN-US">olymer </span><span lang="EN-US">i</span><span lang="EN-US">nclusion </span><span lang="EN-US">m</span><span lang="EN-US">embrane (PIM) method. This study aims to generate PIM, separate the metal ion chromium (VI) using PIM and determine the effect of the concentration of the feed phase, the thickness of the membrane and the amount of usage of the membrane for ion chromium (VI) diffusion.</span><span lang="EN-US">Polymer </span><span lang="EN-US">i</span><span lang="EN-US">nclusion </span><span lang="EN-US">m</span><span lang="EN-US">embrane (PIM) was made by mixing Aliquat 336-TBP as carrier compounds, PVC as the base polymer, DBE as a plasticizer and THF as a solvent. PIM membrane was placed between the source of analyte as a feed phase and result of the separation as a receiver phase. Feed phase was electroplating waste metal containing chromium (VI) at pH 4, while the receiver phase was a 2 N NaCl solution with a pH 6.7. </span>The change of v<span lang="EN-US">ariable</span>s<span lang="EN-US"> in this study </span>were<span lang="EN-US"> the concentration of the feed phase </span>at various dilution i.e.,<span lang="EN-US"> 100x, 50x and 10x, the thickness of the membrane i.e., 25 μm, 20 μm and 10 μm</span>,<span lang="EN-US"> and the </span>time of <span lang="EN-US">membrane</span> using i.e.,<span lang="EN-US"> 1, 2 and 3 times. The concentration of chromium (VI) diffused after separation process </span>was<span lang="EN-US"> analyzed </span>by <span lang="EN-US">a</span><span lang="EN-US">tomic </span><span lang="EN-US">a</span><span lang="EN-US">bsorption </span><span lang="EN-US">s</span><span lang="EN-US">pectroscopy (AAS). </span>T<span lang="EN-US">he stability of membrane was observed </span>by analyzing the presence of<span lang="EN-US"> membrane</span>’s<span lang="EN-US"> component </span>in the<span lang="EN-US"> feed</span> phase<span lang="EN-US"> and </span>in the <span lang="EN-US">receiver phase</span>. The analysis was conducted by UV-Vis <span lang="EN-US">spectrophotometry</span>. Meanwhile, s<span lang="EN-US">canning </span><span lang="EN-US">e</span><span lang="EN-US">lectron </span><span lang="EN-US">m</span><span lang="EN-US">icroscopy (SEM) </span>analysis was used <span lang="EN-US">to determine the morphology of membrane surface.</span><span lang="EN-US">The results showed that the chromium ion concentration </span>diffused<span lang="EN-US"> from the feed phase was 99.24</span><span lang="EN-US">%</span>, mean<span lang="EN-US">while the 85.88</span><span lang="EN-US">%</span> of it diffused to the receiving phase<span lang="EN-US">. The highest Cr(VI)</span> ions<span lang="EN-US"> diffus</span>ion was occured at<span lang="EN-US"> the first use of PIM membrane with a thickness of 10 μm and the concentration of the feed phase</span> was<span lang="EN-US"> 10.55 ppm</span> (resulted from 100 times dilution)<span lang="EN-US">. </span>Therefore, i<span lang="EN-US">t can be concluded that the diffusion of chromium (VI) ion was influenced by the concentration of feed phase, the thickness of membrane and </span>the number of membrane application<span lang="EN-US">.</span></p>

Extraction of copper from wastewater through supported liquid membrane using tri-ethanolamine as a carrier

In the present work, the extraction of copper(II) ions through a tri-ethanolamine/cyclohexanone-based supported liquid membrane (SLM), has been investigated. The polypropylene (Celgard 2400) was used as a membrane. The various experimental parameters at room temperature including feed pH, feed, carrier, and strip phase concentration were optimized to acquire the optimum conditions for the extraction of copper(II) ions from waste water. Oxalic acid, sodium carbonate, sodium sulfate, nitric acid, and ethylene-di-amine-tetra-acetate (EDTA) were tested for best stripping reagent for SLM configuration. The extraction time, flux value, stoichiometry of the complex formed, and membrane stability was also investigated. The optimum experimental conditions for copper(II) extraction were 3.5 mol/L tri-ethanol amine (TEA) in the membrane phase as carrier, 1 mol/L hydrochloric acid and 3.17 × 10−3 mol/L copper(II) in the feed, and 0.03 mol/L EDTA in the strip solutions. Under these optimum conditions, the extraction time was found to be 120 min and membrane was stable for about 10 consecutive experiments. The transport efficiency of copper(II) ions was found to be 87% under the optimized conditions.

A new method for estimation of the overall mass transfer coefficient in pertraction

The pertraction of benzoic acid was studied in an agitated bulk liquid membrane system. The simultaneous effect of the operational parameters such as initial feed phase concentration (cf0), bulk liquid membrane volume (VLM) as well as a molecular descriptor (MD) which represent the organic solvent is discussed. The response surface methodology with a full factorial design and multiple linear regression analysis was applied for the description of the dependence of benzoic acid fluxes on selected parameters and descriptors.It was experimentally confirmed that the response surface methodology enables the determination of the parameter which can be considered as the apparent overall mass transfer coefficient dependent on the volume of the liquid membrane and the liquid membrane solvent in the studied system.It was additionally found that the extended linear regression models with two and/or three factor interaction terms describe over 99.5% of the total variance between the maximum output fluxes of benzoic acid and selected variables. To evaluate the prediction accuracy of the empirical regression models, the standard validation procedures were carried out. For example, the highest prediction accuracy (over 99.5%) was achieved in the case of the models involving three variables (cf0 and VLM parameters and 3D Wiener index (W3D)), and additionally, two factor interaction terms (cf0×VLM, cf0×W3D,VLM×W3D).Alternatively, similar models with comparable prediction accuracy but exploiting the squared Moriguchi octanol–water partition coefficient (MLOGP2) or reciprocal hyper-detour index (Rww) can be formulated. However, in this case, the models involves three factors interaction term (cf0×VLM×MD).

Selective separation of salbutamol enantiomers with simultaneously synergistic extraction and stripping method

Enantioselective separation of salbutamol enantiomers was carried out through the simultaneously synergistic extraction and stripping method with Ο,Ο-dibenzoyl-(2S,3S)-tartaric acid (+)-DBTA and di (2-ethylhexyl) phosphoric acid (D2EHPA) as chiral and non-chiral extractants, respectively. Chiral recognition mechanism of salbutamol enantiomers with (+)-DBTA was investigated using the Density Functional Theory (DFT) methods. The results showed that the chiral recognition in separation process was realized by the hydrogen-bond interaction. The binding energy of the complex resulting from (+)-DBTA and R-salbutamol was −86.14kJ/mol, which was higher than that of the complex resulting from (+)-DBTA and S-salbutamol. The synergistic extraction experiment was preliminarily performed and the maximum separation factor was up to 1.65. Enantioseparation of salbutamol was conducted in the hollow fiber supported liquid membrane process. Various operating conditions, including the feed phase concentration, the component of membrane phase, the flow rate, and the pH of stripping side, were investigated. The results showed that the mass transfer resistance mainly focused on the membrane phase. The synergistic effect in liquid membrane system was also discussed. When the ratio of chiral to achiral extractant was 1.0:0.6, the separation factor was up to 2.0 in the stripping phase.

Comparison of solvent extraction and LEM extraction in static mixer for recovery of Mo(VI) from dilute aqueous solution

In this paper, the liquid emulsion membrane extraction of molybdenum(VI) has been conducted in static mixer. The performance in LEM mode is compared to a conventional solvent extraction mode. The rate of extraction in LEM mode is found to be significantly higher than conventional solvent extraction. Study reveals that the optimum residence time, height of the static mixer and optimum surfactant concentration are the deciding parameters of the performance of static mixer. The effect of various parameters such as superficial velocity of aqueous phase and organic phase, residence time, initial Mo(VI) concentration in feed phase, height of column, and surfactant concentration on rate of extraction has been investigated. A mathematical model is developed to predict volumetric mass transfer coefficient (kLa) in a static mixer. The kLa value is reduced from 0.045s−1 to 0.015s−1 when height of the mixer was increased from 31cm to 93cm respectively under the same hydrodynamic conditions. This anomalous decrease of kLa with increase in height is due to acid extraction by TBP which reduces driving force for extraction of Mo(VI). HTU for solvent extraction and LEM extraction are estimated as 0.67m and 0.15m respectively which indicates less mass transfer resistance in LEM.

Recovery of Synthetic Dye Red 3BS from Simulated Wastewater using Supported Liquid Membrane Process Containing Immobilized Kerosene-tridodecylamine Liquid Membrane

The discharge of reactive dyes into the environment has led to the toxicity problems especially to the aquatic organism. Therefore, there is a necessity for treatment of the reactive dyes from wastewater. In this work, Red 3BS reactive dye was separated using supported liquid membrane process. Commercial polypropylene (PP) membrane was used as a support of kerosene-tridodecylamine liquid membrane. Several important parameters such as flow rate, pH of feed phase, initial concentration of feed phase and stripping agent concentration were investigated. The result shows that for 50 ppm Red 3BS solution containing 0.00001M Na2SiO3 almost 100 and 89% of Red 3BS was removed and recovered respectively at the favorable condition of 0.1 M NaOH as a stripping agent, pH 3 of feed phase and 100 ml/min of flow rate.

Removal of Phenol from Wastewater by Supported Liquid Membrane Process

Phenol is considered a pollutant in the environment due to its toxicity and carcinogenic effect. Supported liquid membrane (SLM) is a good and promising technology for the removal of phenol from wastewater because it provides maximum driving force for the separation of targeted solute and simultaneous extraction and stripping process which lead to excellent separation. In this research, kerosene and palm oil liquid membranes were used as liquid membrane phase, aqueous phenol as the feed phase and aqueous sodium hydroxide as the stripping phase. Several factors such as feed phase pH, feed phase flow rate and concentration of stripping phase were studied. The results show that the best extraction performance can achieve 35% at pH 4 of feed phase, 150 ml/min feed flow rate and 1.0 M of stripping phase concentration. The result was used to determine the probability of using palm oil as a liquid membrane. In the determination of the potential of using palm oil as the membrane phase, the results show that an equal portion of palm oil and kerosene mixture performed the best extraction with 43% efficiency.

Selective removal of zinc using tri-ethanolamine-based supported liquid membrane

This work is a comprehensive study on the selective removal of Zn (II) from aqueous solution using a flat-sheet polypropylene-supported liquid membrane system. Tri-ethanolamine (TEA) dissolved in cyclohexanone was used as a carrier for extraction of zinc ions through supported liquid membrane. Different parameters affecting the zinc ion transport were studied. The experiments were performed at various operating conditions such as metal and acid concentration in feed phase, strip phase concentration, and carrier concentration, to find the best set of parameters that would yield the maximum extraction. The extraction time, flux value, the stoichiometry of the complex formed, and membrane stability was also investigated. The experiments were performed in co-transport mode. The optimized conditions obtained for zinc ion transport are as follows: 2.30 × 10−4 mol/dm3 of Zn2+ ions and 1M of HCl in feed solution, 50% TEA in cyclohexanone in membrane phase, and 0.7M of NaOH in stripping phase. Under these optimum conditions, the membrane is stable for about 10 consecutive experiments. The extraction efficiency was found to be 87% in 120 min.

Study of Phenol Removal from Aqueous Solutions by a Double Emulsion (W/O/W) System Stabilized with Polymer

Polybutadiene rubber was used for stabilization of the emulsion for removal of phenol from aqueous solution via emulsion liquid membrane technique. The results showed that the addition of the polymer increased the stability of the emulsion, considerably. The effect of various parameters such as polymer concentration, temperature, mixing intensity, internal phase concentration, phases ratio, and pH of feed phase was studied. It was found that by increasing the volume ratio of emulsion to feed, internal phase concentration, and decreasing pH, the extraction efficiency was increased. Under optimum conditions, an extraction efficiency of 92% was obtained within only 35 minutes.

A comparative study of experimental optimization and response surface methodology of Bi(III) extraction by emulsion organophosphorus liquid membrane

This paper considers a new approach in the study of bismuth extraction by di(2-ethylhexyl)phosphoric acid (D2EHPA) as an organophosphorus carrier. A comparative study on the optimization of process parameters of an emulsion organophosphorus liquid membrane (EOgLM) by experimental work and response surface methodology (RSM), according to a Box–Behnken design (BBD), was carried out. Emulsion stability was achieved by the TritonX-100 as biodegradable surfactant in a dichloromethane membrane. The transport of Bi(III) ions from the acidic nitrate medium was evaluated from yield of extraction as analytical response, and the optimum conditions were initially determined by optimizing one parameter at the time. The extraction of Bi(III) was found to be total. The comparison between the values, experimentally optimized and those RSM optimized, was accomplished by optimizing the following parameters: D2EHPA/TritonX-100 ratio, initial feed phase concentration and concentration of internal phase. The comparison showed that all the values were in good agreement and all interactions of the chosen variables are significant except for the internal phase concentration and initial feed phase concentration. It was observed that it is necessary to decrease the acidity of the stripping phase to make the Bi extraction by EOgLM process more efficient.

Prediction of Kraft Lignin Extraction Performance Using Emulsion Liquid Membrane Carrier-Diffusion Model

This study presents the model to predict the performance of emulsion liquid membrane (ELM) to extract kraft lignin. Kraft lignin is one of the raw material that can be convert into biodiesel and also applied in producing large amount of chemical product such as vanillin. ELM is a separation method which can separate component without mechanical support. In this study, ELM model was developed and solved using MATLAB software. Three parameters were investigated in this study such as treat ratio, carrier concentration and initial concentration of feed phase. The study shows that ELM performs best at treat ratio of 1:5, concentration carrier of 0.3M and 0.5g/L of initial concentration of feed phase.

Extraction separation of Co(II) from Ni(II) in H2SO4 solutions with carriers in hollow-fiber contactors

The separation of Co(II) from Ni(II) in H2SO4 solution across a hollow fiber membrane containing D2EHPA carriers dissolved in kerosene was studied. The Co(II) was simultaneously re-extracted to a strip phase containing H2SO4. Experiments were conducted to determine the effects of the feed pH (4–5), carrier concentration (0.1–0.5 mol/dm3), strip acidity (0.1–2 mol/dm3), and flow rates of the three phases (200–600 cm3/min). The extraction efficiency for each metal ion was found to increase with increasing flow rate of the feed phase, feed pH, and D2EHPA concentration in the extraction module. Co(II) was preferentially extracted over Ni(II) by D2EHPA under the same extraction conditions. In the extraction module, the separation factor βCo/Ni increased with increasing flow rate of the feed phase and D2EHPA concentration but decreased with increasing feed pH. In the re-extraction module, the recovery of Co(II) increased with increasing the feed pH, D2EHPA concentration, and flow rate of the strip phase but decreased with increasing the strip acidity. At a feed pH of 4, the percent extraction and recovery of Co(II) were 81% and 26.4% (Ni/Co–11% in strip phase), respectively. The percent extraction and recovery for Co(II) using one-stage HFMCs were better than those using two-stage HFMCs.

Performance evaluation of vanadium (IV) transport through supported ionic liquid membrane

Increasing use of vanadium in different industries including alloys and steel manufacturing, electrochemical coating and catalysts causes environmental concern about the toxic effluents. In the present research, the extraction of vanadium in supported ionic liquid membrane was studied. The effect of operational conditions on the process performance such as initial feed phase concentration, pH of the feed solution, pore size of the membrane support, type of ionic liquid charged on the support and stripping agent solution was investigated. Vanadium was effectively transported from the feed phase to the stripping phase of ammonia solution using the room temperature ionic liquid, tri-n-octyl methyl ammonium chloride (TOMAC) embedded in the support membrane. Selective transport of vanadium from its mixture with chromium ions was carried out applying TOMAC as carrier. It was also observed that addition of a slight amount of a second room temperature ionic liquid, 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl] imide [BMIM][NTF2], improved the vanadium extraction process considerably.

Emulsion liquid membranes for cadmium removal: Studies of extraction efficiency

Emulsion liquid membrane (ELM) process suffers from emulsion instability problem. So far, emulsion produced by mechanical methods such as stirrer and homogenizer has big size and high emulsion breakage. This paper discussed the application of emulsion produced by sonicator to extract cadmium in a batch ELM system. The emulsions consist of N,N-Dioctyl-1-octanamine (trioctylamine/TOA), nitrogen trihydride (ammonia/NH4OH), sorbitan monooleate (Span 80), and kerosene as carrier, stripping solution, emulsifying agent, and organic diluent, respectively. Effects of comprehensive parameters on extraction efficiency of Cd(II) such as emulsification time, extraction time, stirring speed, surfactant concentration, initial feed phase concentration, carrier concentration, volume ratio of the emulsion to feed phase, and pH of initial feed phase were evaluated. The results showed that extraction efficiencies of Cd(II) greater than 98% could be obtained under the following conditions: 15 minutes of emulsification time, 4 wt.% of Span 80 concentration, 4 wt.% of TOA concentration, 15 minutes of extraction time, 250 rpm of stirring speed, 100 ppm of initial feed concentration, volume ratio of emulsion to feed phase of 1:5, and initial feed pH of 1.53.

The Separation of Aromatic Hydrocarbons Through a Supported Ionic Liquid Membrane

Ionic liquids can be considered as environmentally friendly solvents because of their low vapor pressures. Room-temperature ionic liquids are used as a supported liquid membrane for separation of aromatic from aliphatic. Aromatic hydrocarbons, benzene, toluene, ethylbenzene, and p-xylene are successfully transported through the polypropylene supported ionic liquid membrane based on 1-methyl-3-octyl imidazolium chloride. The separation performances, represented by the percentage extraction and separation factor, are analyzed systematically by varying the operating parameters: the contact time, membrane phase composition, and initial feed phase concentration. The mathematical models that have been used to simulate experimental data have been discussed. The scanning electron microscope combined with energy-dispersive X-ray analysis of membranes after continuous operation shows that the membrane phases are still retained within the membrane pores and only small losses of the membrane phase initially located on the surface are observed.

Recovery of Golden yellow and Cibacron LSG dyes from aqueous solution by bulk liquid membrane technique

Tri-n-butyl phosphate (TBP) was used as carrier for the transport of Golden yellow and Cibacron LSG dyes through a hexane bulk liquid membrane. The transport efficiency of dyes by TBP was investigated under various experimental conditions such as pH of the feed phase (dyes solution), concentration of the receiving phase (NaOH solution), concentration of TBP in membrane, rate of stirring, effect of transport time, type of solvent, dye concentration in feed phase, effect of temperature.. The maximum transport dyes occurs at ratio of 1:1 TBP-hexane At pH 3.0 0.1 (feed phase) the transport dyes decreased. At high stirring speed (300 rpm) the dyes transport from the feed phase to the strip phase was completed within 60 minutes at <TEX>$27^{\circ}C$</TEX>. Under optimum conditions: Feed phase 100 mg/L dyes solution at pH 1.0 0.1, receiving phase 0.1 mol/L NaOH solution, membrane phase 1:1 TBP-hexane , Stirring speed 300 rpm and temperature <TEX>$27^{\circ}C$</TEX>, the proposed liquid membrane was applied to recover the textile effluent.