Emulsion Liquid Membrane System Research Articles

Natural eutectic solvents and graphene integrated within emulsion liquid membrane system for sodium removal from crude biodiesel

This study reports a new technique for sodium ion removal from biodiesel using a green emulsion liquid membrane (GELM) system based on natural deep eutectic solvents (NADESs) and graphene. The DES consists of choline chloride with glycerol and lactic acid, and tetramethylammonium chloride with glycerol and lactic acid. COSMO-RS software was used to compute the intermolecular interaction of sodium with hydrogen bond acceptors and donors of the NADES. The simulation shows that NADES was the most effective stripping phase for sodium ion removal, which follows the experimental results. The investigation on the stability of ELM and sodium (830 ppm of initially) extraction efficiency showed that the GELM-NADES technique can achieves a sodium ion extraction efficiency of 99.6 % (3.17 ppm) with high stability at a homogenization speed of 8000 rpm, homogenization time of 3 min, HBA: HBD molar ratio of 1:4, 3 wt% of span 80, 10 minutes of extraction time, 400 rpm stirring speed and 0.5 treatment ratio. The presence of graphene (0.3 g) in the system further enhanced the efficiency and shortened the required extraction time from 6 to 4 min to meet the ASTM D6752 standards. The transport mechanism of sodium ions into the ELM phases adheres to the first-order kinetics model and film theory mechanisms. The overall mass transfer coefficient KO, mass transfer coefficient of the external phase in agitated reactor KM, and interfacial reaction rate constant KF of 5.188×10−9,1.373×10−7,and 5.392×10−9 m/s, respectively. ELM system with NADES and graphene can provide a cleaner route for biodiesel downstream processing.

Removal of furosemide from water by emulsion liquid membrane: Influence of experimental conditions and real water matrices

This work investigates the removal of furosemide (FSM) from low pH aqueous phase by emulsion liquid membrane (ELM). The influence of various experimental conditions on FSM permeation rate and subsequent emulsion stability, such as surfactant concentration, diluent type, stripping solution concentration, feed solution pH, stripping solution/membrane solution volume ratio, emulsification time and speed, stirring rate, initial FSM concentration, and emulsion/feed solution volume ratio, was evaluated. The ability to extract FSM in different natural complex matrices was examined. The ELM system is formed by Span 80 (5% w/w) as surfactant, hexane as diluent, NaOH (0.01 N) as stripping agent, stripping solution/membrane solution volume ratio of 1/1, treatment volume ratio of 20/200, and mixing rate of 200 rpm. The treatment process demonstrates complete removal of FSM within a remarkably short time span of 20 min. In seawater and natural mineral water, the extraction efficiency is 94.3% and 96.8%, respectively, after 20 min. Additionally, the stripping efficiency of FSM is reported to be excellent (100%), demonstrating the remarkable ability of ELM to remove and recover FSM from water. For these reasons, the ELM technique is a particularly interesting process for treating FSM-contaminated water.

Integration of deep eutectic solvent and activated carbon in emulsion liquid membrane system for soap removal from crude biodiesel

The present work investigated the soap removal from crude biodiesel (BD) using a new technique known as (DES-based ELM/AC), which is a deep eutectic solvent (DES) -based emulsion liquid membrane with the presence of activated carbon (AC). In this system, the DES was introduced as a stripping phase in the DES-ELMs while the AC was introduced into the membrane phase as due to its interaction with the potassium species in the soap molecules with the presence of active sites on the AC surface. The effect of different parameters on the soap extraction efficiency such as the DES molar ratio, DES: BD ratio, surfactant concentration, mixing speed, duration process, and AC dosage were investigated. The results showed that in comparison to adsorption and DES-based ELM, the synergistic effect provided by DES-based ELM/AC technique showed superior removal efficiency at 97.61%. Highest removal efficiency of 99.75%, which is equivalent to 1.87 ppm soap content in the BD, was achieved at 2 wt% of the surfactant, 0.5 wt% of AC, 1:4 DES molar ratio as stripping phase, 1:1 DES: BD ratio, 400 rpm mixing speed and 6 min extraction time. The soap transport follows the first order kinetic model, with a rate constant of 0.627 min -1. This method offers a viable alternative to the conventional water-based purification process. It demonstrates the effective purification of crude BD without the use of a large amount of water/washing agent in comparison to conventional water washing, thereby offering a more sustainable solution for the purification of BD.

Stability of emulsion liquid membrane using blended nonionic surfactant and multi-walled carbon nanotubes (MWCNTs) for methylparaben removal

The emulsion instability is a significant drawback of the emulsion liquid membrane (ELM) technique for large-scale industrial separations. The synergistic effect of blended surfactant (Span 80 and Span 20) and multi-walled carbon nanotubes (MWCNTs) on ELM stability for methylparaben removal were studied. Emulsion (Span 80 + Span 20 + MWCNTs; HLB 5.7) possesses the highest ESI values at all time intervals. The %swelling of emulsion is reduced by 42% by using blended surfactants (Span 80 and Span 20) and nanoparticles (MWCNTs). The overall mass transfer coefficient is increased by 4.746% by adding MWCNTs to the ELM system. The energy (E) needed to detach a particle from the interface is estimated as 0.7286 × 10−13 J (1.7727 × 107 kT). This indicates effective irreversible adsorption of particles at the interfaces and influences the particles capability to stabilize the emulsion.

Design and manufacture of emulsion liquid membrane based on various amine extractants for separation and extraction of succinic acid from fermentation broth

The aim of this study was to design a new emulsion liquid membrane (ELM) system for the separation of succinic acid from aqueous solutions. The concentration of succinic acid varied from 20 to 60 mmol·L−1. The prepared ELM system includes tributylamine (TBA) as a carrier, commercial kerosene as a solvent, Span 80 as a surfactant, and Na2CO3 as a stripping agent. In order to control the membrane swelling, different values of cyclohexanone were added to the membrane phase. The effect of various empirical variables on the extraction of the succinic acid such as acid concentration in the feed solution, initial feed concentration, carrier concentration, the stirring speed of the extraction, Na2CO3, surfactant, and cyclohexanone concentrations, and treat ratio in the ELM system. The best result was obtained when TBA was used as the carrier. The final acid extraction efficiency was independent of pH variations of the aqueous feed solution. The extraction of succinic acid solution with a concentration of 40 mmol·L−1 was improved by increasing the treat ratio 1:7–1:3, stripping phase concentration 0.5–1.5 mol·L−1, stirring speed 300–500 r·min−1 and cyclohexanone concentration in the membrane phase 1.2–1.6 mol·L−1. No considerable effect on the extraction rate was observed for the carrier concentration in the membrane phase. But, the surfactant concentration in the feed phase showed a dual effect on the extraction efficiency.

Computational analysis of citric acid pertraction in emulsion liquid membranes

AbstractCitric acid is one of the most widely used acids in industry, and its recovery from waste streams is critical. Emulsion liquid membrane (ELM) is one of the most effective recovery methods that has been investigated in recent years. Numerous transport phenomena parameters affect the efficiency of this process. From the process equipment design point of view, optimization based on overall cost is of great importance, and important equipment sizing decisions/constraints must be considered. A physics‐based model for a full‐scale simulation of ELM systems is very useful. This work is focused on developing and verifying such a model. A coupled particle/mixture simulation was carried out in this work, and the modelling results were fitted on the experimental data. The novelty of this modelling work is physics‐based results based on the system's geometry and its effects on the mass transfer resistances. Since the model is physics‐based, the model is capable of simulating similar systems with any geometry or experimental conditions.

Emulsion Liquid Membrane Screening for Ibuprofen Removal from Aqueous Solution

Ibuprofen (IBP) has become increasingly widespread in our environment, posing a major problem for treatment by its high occurrence in low concentrations. Emulsion liquid membrane (ELM) technology has emerged as an alternative solution for removing low concentration pollutants from contaminated sources. This study screened ELM formulations for the removal of IBP from an aqueous solution. Emulsion screening was conducted using a series of reactants, including petroleumbased diluent, green diluent, and acidic/alkaline stripping agent. The ELM system, which included hexane (diluent), 0.1 M sodium carbonate, Na2CO3 (stripping agent), 2 wt% Aliquat 336 (carrier) and 4 wt% Span 80 (surfactant), achieved the highest IBP extraction efficiency of 97%.

Acetaminophen Extraction Study using Vegetable Oil-Based Emulsion Liquid Membrane: The Juxtaposition of Carrier and Internal Phase

Extraction of Acetaminophen (ACTP) using vegetable oil-based emulsion liquid membrane (ELM) was investigated. ELM consists of membrane and internal phases that form the primary water-in-oil (W/O) emulsion by using an ultrasonic probe while the external phase consists of an ACTP aqueous solution. In promoting a greener development, vegetable oil was incorporated in the formulation of ELM, replacing the hazardous conventional petroleum derivatives diluent. The potential of vegetable oil-based solvent was confirmed via a compatibility study with the carrier and surfactant whereby sunflower oil showed an auspicious potential to be employed as a diluent in ELM formulation. The effect of emulsion formulation parameters of the vegetable oil-based ELM was investigated to obtain its best formulation, by taking into consideration the ACTP extraction efficiency. The extraction study carried out using Trioctylamine (TOA) and Aliquat 336 as carrier and ammonia & sodium chloride (NaCl) as internals phase were compared. The parameters involved are emulsification time, extraction time, and the stirring speed was investigated. These works demonstrated that the ELM system was competent to successfully expel 97.73% of ACTP from aqueous solutions under optimum conditions.

Silver extraction using emulsion liquid membrane system containing D2EHPA-TBP as synergistic carrier: optimization through response surface methodology

ABSTRACT The present investigation deals with silver extraction using an emulsion liquid membrane. The emulsion liquid membrane system consists of paraffin as organic phase, Span 80 as surfactant, Di-(2-ethylhexyl) phosphoric acid (D2EHPA) and Tributyl Phosphate (TBP) as carrier, and hydrochloric acid as stripping agent. Experiments were designed and modeled by response surface methodology using Design Expert 11 software, which determines the extraction rate as a function of Span 80 concentration, D2EHPA concentration, TBP concentration, HCl concentration, and treatment ratio. The ANOVA results indicate that the model is statistically significant because of the high R 2 (0.9828) and the low p-value of <0.0001. The results showed that the silver extraction increases by increasing all affecting parameters up to their optimal values and after that extraction rate decreases with increasing of them. The process was optimized to obtain maximum extraction rate, minimum D2EHPA concentration, and minimum treatment ratio. The optimal conditions were obtained at a surfactant concentration 3.26% (V/V), D2EHPA concentration 0.0045 mol/L, TBP concentration 5% (V/V), HCl concentration 0.56 mol/L, and treatment ratio 0.5. Under these conditions, the silver extraction rate was 99.87%.

Optimization and prediction of safranin-O cationic dye removal from aqueous solution by emulsion liquid membrane (ELM) using artificial neural network-particle swarm optimization (ANN-PSO) hybrid model and response surface methodology (RSM)

The cationic dye safranin-O was removed from an aqueous solution using the Emulsion Liquid membrane (ELM) method. The ELM system consists of a diluent (hexane) and a surfactant (Span 80). Sulfuric acid (H2SO4) solution was used as an internal aqueous phase. The key parameters regulating the safranin-O dye removal were investigated. Twenty-nine (29) experiments were conducted, with various parameters impacting the removal of the cationic dye safranin-O from aqueous solution using the ELM approach, including surfactant content and internal phase concentration in H2SO4 dye concentration and stirring speed. The RSM with Box–Behnken Design (BBD) was used to optimize and predict the ELM safranin-O cationic dye removal experiments. The model produces 99.68% separated safranin-O in under 2 min of contact time with optimal operation conditions. Furthermore, for forecasting the removal of the cationic dye safranin-O from an aqueous solution by ELM technique, a novel optimization approach based on merging an artificial neural network (ANN) algorithm with a metaheuristic technique, namely PSO, has been proposed. The PSO technique was used to determine the optimal ANN parameter values.

Removal of zinc by emulsion liquid membrane using lecithin as biosurfactant

The present investigation deals with zinc extraction using emulsion liquid membrane (ELM) method with the help of lecithin as biosurfactant. The emulsion liquid membrane system consists of paraffin as organic phase, lecithin as biosurfactant, Di-(2-ethylhexyl) phosphoric acid (D2EHPA) as extractant, and sulfuric acid as stripping agent. In this study, five parameters affecting the extraction performance, i.e., lecithin concentration, pH of feed solution, treatment ratio, internal phase to organic phase volume ratio, and D2EHPA concentration were investigated. The stability of emulsion was determined by specifying breakage and swelling of the emulsion. The experiments were performed under ambient conditions to extract zinc with the initial concentration of 250 mg/L. The extraction step was completed after 10 minutes by stirring at 500 rpm. Optimal conditions were obtained at the biosurfactant concentration of 3% (v/v), pH 3, treatment ratio 0.3, internal phase to organic phase volume ratio 0.1, and D2EHPA concentration 6% (v/v). Under optimal conditions, zinc extraction was 98.38%. In these conditions, the breakage and swelling of the emulsion were 6.29% and 8.56%, respectively.

Evaluation of mean diameter and drop size distribution of an emulsion liquid membrane system in a horizontal mixer-settler

A W/O emulsion consisting of distillated water, kerosene and Span 80 was prepared to be employed in a horizontal mixer settler. The effect of stirring speed, flow ratio, total flow, Span 80 concentration and the internal to membrane phase volume ratio on the Sauter mean diameter (D32) of emulsion, drop size distribution and also the holdup were investigated without mass transfer effect. The results revealed that, with increasing the stirring speed, the D32 decreased and the emulsion holdup increased. However, the emulsion globules breakage incremented due to producing high shear forces. For the ELM system with the surfactant concentration higher than 3wt.%, the D32 increased due to the emulsion swelling and the holdup reduced. In addition, raising the flow ratio and the total flow increased the drop size which led to the reduction in the holdup. Besides, for the internal to membrane phase volume ratio higher than 0.4, the drop size increased. Empirical correlation was presented to predict the D32 with average absolute relative errors (AAREs) of 3.9%. The drop size distribution was conformed to normal distribution, and α and β parameters have been correlated with AAREs of 3.4% and 3.7%, respectively.

Enhancing emulsion liquid membrane system (ELM) stability and performance for the extraction of phenol from wastewater using various nanoparticles

Enhancing emulsion liquid membrane system (ELM) stability and performance for the extraction of phenol from wastewater using various nanoparticles

Design of a solar reactor for the removal of uranium from simulated nuclear wastewater with oil-apatite ELM system

Nuclear wastewater containing uranium ions is a serious threat to the environment. In this study, uranium (VI) ions were adsorbed from the synthesized wastewater by hydroxyapatite nanoparticles (NHAP) in the emulsion liquid membrane (ELM) process. The NHAP was dispersed in the oil, and ELM globules were formed by injecting the NHAP-oil phase into the wastewater. The FT-IR of NHAP, before and after separation process showed the hydroxyl, amine, and phosphoryl groups are important to immobilization of U(VI) ions in oil phase. The morphology of NHAP was identified with FE-SEM, with the NHAP size intially 50 nm, while and at the end the size was about 1 μm. The following optimum conditions were selected: pH = 4, NHAP concentration = 12.4 gL-1, volume of ELM = 43 ml, retention time = 45 min, air flow rate = 0.5 Lmin-1 and impeller rotation speed = 200 rpm. The viscosity of the oil phase decreased with solar radiation and the U(VI) adsorption on the NHAP surface was improved. The oil and air phase distribution within the water phase was simulated. Adsorption isotherms, thermodynamic parameters and kinetic data were investigated.

The effect of operational conditions on the stability and efficiency of an emulsion liquid membrane system for removal of uranium

In the present study, an emulsion liquid membrane (ELM) system containing 2-Thenoyltrifluoroacetone (TTA) as a carrier was applied for extraction of uranium from dilute aqueous solutions. The stability of the ELM globules was modified by adding a polymeric stabilizer (Polyisobutylene or PIB) to the membrane phase. Several operational parameters such as surfactant concentration, stirring speed, treat ratio and the internal to membrane phase volume ratio were optimized for achieving the maximum uranium extraction with minimum emulsion breakage and swelling. The results showed that the best extraction efficiency and emulsion stability is obtained at 2 wt% of the surfactant, 1.5 wt% PIB, stirring speed of 300 rpm, treat ratio of 1:10 and internal to membrane phase volume ratio of 1:1. With these conditions, the extraction efficiency of 95.2% was obtained within 5 min and the measured values of emulsion breakage and swelling were 0.39% and 0%, respectively. The optimized emulsion formulation and operating conditions were used for continuous extraction of uranium in a horizontal mixer-settler. The ELM performance in uranium extraction was also compared to the conventional solvent extraction method with the same organic solvent and extractant in batch and continuous modes.

Separation of molybdenum from spent HDS catalysts using emulsion liquid membrane system

In this study, the selective extraction of molybdenum (Mo) from the spent hydrodesulfurization (HDS) catalysts using emulsion liquid membrane method was investigated. Cyanex 272 and ammonium fluoride (NH4F) had excellent efficiency in selective extraction of Mo from the spent catalysts as extractant and stripping agent, respectively. Other parameters including surfactant concentration, speed of agitation, contact time, treat ratio (external to emulsion phase volume ratio), and internal to membrane phase volume ratio were effective on the performance of the emulsion liquid membrane system. Besides, the stability of emulsion was determined by specifying the emulsion breakage and swelling at each stage. The optimal separation of Mo under operating conditions consists of 0.3 M Cyanex 272, 3 %wt. Span 80, 1 M ammonium fluoride, 25 min contact time with the agitation speed of 350 rpm, treat ratio of 2.5 and, internal to membrane phase volume ratio of one was obtained. Under these conditions, more than 75 % of the Mo was selectively transferred to the internal phase.

Leakage and swell in emulsion liquid membrane systems: Comparing continuous stirred-tank reactor and batch experiments

Emulsion liquid membrane (ELM) systems can efficiently extract and concentrate dilute solutes in a variety of applications and chemistries. Internal phase leakage and swell reduce extraction efficiency and concentration, which limits their use. Nearly all studies of ELM leakage and swell have been conducted in batch systems, although continuous flow systems are preferred for industrial applications. The objective of this investigation was to assess the ability of batch experiments to predict continuous system performance with respect to internal phase leakage and swell. The effects of five factors (surfactant concentration, osmotic pressure, membrane viscosity, internal phase volume fraction, and extraction vessel stir rate) on leakage and swell were measured in a continuous stirred-tank reactor (CSTR) system without solute extraction. The results were compared with those reported previously for a batch system with the same experimental conditions and vessel geometry. Overall, the effects of the five factors in the CSTR system are qualitatively consistent with the batch system observations, suggesting that the influential variables in the batch system are similarly influential in the CSTR system. Leakage and swell in the CSTR and batch systems are correlated with similar amounts of swell in both systems but consistently smaller leakage in the CSTR configuration.

Extraction of reactive dye via synergistic Aliquat 336/D2EHPA using emulsion liquid membrane system

Facilitated transport of Orange 3R was performed by means of emulsion liquid membrane (ELM) technique containing double extractants of Aliquat 336 and D2EHPA as extractant and synergist extractant, respectively. Cooking palm oil, sorbitan monooleate (Span 80), and sodium hydroxide were used as diluent, surfactant and stripping agent, respectively. Several parameters influencing the extraction of Orange 3R via ELM, namely effect of extraction time, agitator speed, Span 80 concentration and treatment ratio, were experimentally investigated and optimized using response surface methodology (RSM). Results demonstrated that about 91% of Orange 3R was successfully extracted under optimum conditions of 12 minutes of extraction time, 413 rpm of agitator speed, 3.2% (w/v) of sorbitan monooleate, and 1:9.8 of treatment ratio. Additionally, the aforementioned optimum conditions were found to be more suitable to treat low concentration of Orange 3R (less than 100 ppm) from simulated textile wastewater. The findings reveal that reactive Orange 3R dye is able to be selectively extracted using double extractants via sustainable ELM process as well as providing high potential application in the dye removal from industrial textile wastewater.

Development of vegetable oil-based emulsion liquid membrane for downstream processing of bio-succinic acid

Succinic acid has been recognized as a useful platform chemical that can be applied in various industries. The application of bio-based succinic acid is still limited due to high downstream processing cost. In this study, vegetable oil-based emulsion liquid membrane (ELM) process is proposed to recover succinic acid from fermentation broth. The ELM system consists of three main liquid phases; external feed, membrane, and internal stripping. The liquid membrane phase was prepared by dissolving Amberlite LA2 and Span 80 in palm oil, while, the internal phase comprises of sodium carbonate solution, Na2CO3. The influence of feed, stripping agent and carrier concentration, treat ratio, as well as liquid membrane recycling on ELM performance were studied. The results showed 10g/L of initial concentration, 1.0M of Na2CO3, 0.7M of Amberlite LA2, and treat ratio of 1:5 is the best condition with almost 100% recovery and enrichment of 21 times. The recycled liquid membrane concentrates the succinic acid up to 12 times. Therefore, the proposed ELM is a potential technology to extract bio-succinic acid.

Preliminary Study of Emulsion Liquid Membrane Formulation on Acetaminophen Removal from the Aqueous Phase.

The aim of this study is to develop an Emulsion Liquid Membrane (ELM) system for the extraction of acetaminophen (ACTP). Firstly, ELM was formulated by the screening of liquid membrane components where the compatibility of diluent with other membrane phase components was investigated. The chosen carrier, diluent and stripping solution must comply with the reaction at the interface of the membrane to support the simultaneous processes of extraction and stripping. Therefore, parameters such as stripping agent concentration, volume ratio, initial concentration of feed phase and HCl concentration were investigated. A stable emulsion and maximum acetaminophen removal efficiency of 85% was achieved.