Emulsion Liquid Membrane Technique Research Articles

Green emulsion liquid membrane for desalination: Prototype and techno-economic evaluation

Existence on Earth is presently in jeopardy due to a lack of sufficient water. Liquid membranes (LMs) have acquired widespread recognition as a viable separation technique. The current research seeks to advance desalination significantly using edible oils as a green emulsion liquid membrane (GELM) technique. The initial concentration (Ci), the treatment ratio (TR), which is the ratio of the emulsion to the doner phase (DP), the type of LM, the amount of sequestering agent (SA), and the power of ultrasonication (US) were all investigated as possible impacts on the desalination process. The experiments led to the following conclusions: the presence of SA in the receptor phase (RP) is essential for salt sequestration; the US yields a stable emulsion with a high salt extraction percentage. This study demonstrated the simplicity and efficacy of desalinating simulated seawater using the GELM approach with edible oils, which resulted in 99.9 % desalination without a mobile carrier or an ordinary emulsifier. Corn oil, when used as LM, has enhanced extraction capabilities. The preferred TR was 1:10, the preferred percentage of soluble starch (SS) as an emulsifier and SA was 1 %, the optimum Ci was 25 g l−1, and the optimum US power was 350 W. A techno-economic assessment for desalination by GELM reveals that the production cost is $1.02/m3.

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.

Removal of High Concentrations of Arsenite from Aqueous Solutions by the Emulsion Liquid Membrane Technique

AbstractAs(III) is a dangerous species that contaminates groundwater resources and therefore water purification from this element is necessary. In this study, the removal of As(III) was investigated by the emulsion liquid membrane (ELM) technique due to the high toxicity levels of this species. The effect of various parameters such as hydrochloric acid and arsenic concentration in the feed solution, emulsion to feed ratio, surfactant concentration and type of carrier was evaluated on the arsenic separation efficiency. The results showed that the best type of carrier in terms of emulsion stability and separation efficiency of arsenic ions was di‐(2‐ethylhexyl) phosphoric acid (D2EHPA), and its optimal concentration was about 5 % (v/v). In addition, paraffin as the organic solvent performed better than the mixture of paraffin and kerosene in the separation of As(III) ions. The optimal conditions were obtained at 8 and 0.1 M HCl concentrations for the feed and the internal phases, respectively. Also, the emulsion to feed ratio of 1 : 4.5, the volume ratio of the internal phase to the membrane phase of 1 : 1 and the surfactant concentration of 5 % (v/v) led to achieving the maximum removal of arsenic ions. This work presents a broad perspective of removing As(III) ions from wastewater by carefully examining the parameters influencing the separation of this hazardous element through the ELM method.

Extraction of acid orange 7 from water by emulsion liquid membrane using Tri-dodecyl-amine as extractant

The main objective of this study was to investigate the feasibility of extracting Acid Orange 7 (AO7), a complex reactive dye, from aqueous solutions using a stabilized emulsion liquid membrane (ELM) technique. The ELM formulation comprised tri-dodecylamine (TDA) as the extracting agent, kerosene as the diluting medium, and SPAN 80 as the surfactant. We systematically examined various experimental variables that affect the extraction of AO7. These variables included the concentrations of the extractant and surfactant, internal phase concentrations, the ratio of the membrane phase to the internal phase, the choice of diluting medium and its grade, stirring speed, treatment ratio, and the initial concentration of AO7. Furthermore, we investigated the impact of sodium chloride concentration in the external phase. Our research findings indicate that the optimal conditions for AO7 extraction using the ELM method were as follows: a TDA concentration of 3% (w/w), a SPAN 80 concentration of 9% (w/w), an oil-to-aqueous phase ratio (O/A) of 1:1, kerosene as the diluting medium, H2SO4 as the internal phase, a stirring speed of 200 rpm, a treatment ratio of 1:10, and an initial AO7 concentration of 10 mg/L. Under these precise conditions, an exceptional extraction efficiency of 98.49% was achieved in just 15 min. Under these carefully controlled conditions, an exceptional extraction efficiency of 98.49% was achieved in just 15 min. Consequently, the emulsified liquid membrane extraction process demonstrates significant potential as an advanced separation technique for removing hazardous dyes, particularly in dilute solutions.

Removal of diclofenac using Fe2O3 nanoparticles stabilised emulsion nanofluid membrane

The present investigation focuses on the removal of Diclofenac (DCF) from aqueous solution by Fe2O3 nanoparticles stabilised emulsion nanofluid membrane (ENM) using n-heptane as solvent and Di-2-ethylhexyl phosphoric acid (D2EHPA) as carrier. Parameters like stripping phase (HNO3) concentration, homogenizer speed and hydrophilic-lipophilic balance were varied to achieve the maximum extraction of DCF. ENMs were characterized by photomicrograph and Turbiscan. Emulsion instability is the main hurdle for the application of emulsion liquid membrane technique on an industrial scale. The study also tries to address this issue. The study is novel in a way as the blending of Span 80 and Span 20 surfactants with Fe2O3 nanoparticles provided stability to emulsion and improved the DCF extraction to 97%. Nanoparticles are interfacially active which ensures better stability to the emulsion and improves the extraction efficiency.

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.

Screening of parameters and optimization for green recovery of anionic dye by nanoparticle-ionic liquid-based green emulsion liquid membrane using response surface methodology

An anionic dye, Procion Blue MX- R (PB MX-R) dye was recovered from aqueous feed solution utilizing green emulsion liquid membrane (GELM) technique. GELM was comprised of Rice Bran Oil, (1‑butyl‑3-methylimidazolium chloride) ionic liquid, (ZnO) nanoparticles, Span 80 as surfactant, and NaOH in the internal phase. Plackett-Burman Design was used to examine eleven operating parameters influencing recovery of PB MX-R dye. Further, operating conditions of thus obtained significant parameters for PB MX-R dye recovery by GELM were optimized and maximum recovery was predicted upon utilizing Box-Behnken Design. Under obtained optimized conditions for significant parameters, including PB MX-R dye concentration - 45 ppm, contact time - 12 min, agitation speed - 498.6 rpm, nanoparticle concentration - 0.06 (%, w/v), carrier concentration - 0.9 (%, v/v), and NaOH concentration - 0.095 N, confirmation experiments had validated the elimination of 98.71 ± 0.95 % for PB MX-R dye which was in close agreement with that of predicted one (99 %). Thereupon reusability of membrane phase constituents for reformulation of GELM after demulsification of dye enriched GELM for multiple-time recovery of PB MX-R dye was investigated. The study has confirmed that hence formulated GELM did not diminish and effectively eliminated PB MX-R dye until fifth cycle.

Application of emulsion liquid membrane for removal of malachite green dye from aqueous solution: Extraction and stability studies

Malachite green (MG) dye has various applications as a dyeing material, medical disinfectant and biocide but is also recognized as a teratogenic, carcinogenic, mutagenic and respiratory toxic material which creates dire effects on human beings, aquatic flora and fauna. Hence, the main objective lies in the removal of MG dye from an aqueous stream. In the current investigation, emulsion liquid membrane (ELM) technique was used and the effect of different factors like concentration of carrier, surfactant, stripping phase and its type and volume ratio of membrane to stripping solution on the removal of MG dye were studied. MG extraction efficiency of 94.99% was achieved using emulsion consisting of 2% w/v Span 80, 2% w/v D2EHPA, 0.1 N HCl and membrane phase to stripping phase volume ratio 1. Microscopic studies of the emulsion revealed the formation of well-defined and large number of globules with very less coalescence which resulted in high removal of MG dye. The physical stability of the emulsion was analysed and the phase separation was comparatively less at various time intervals suggesting that the conditions used for preparing the emulsions are suitable. Fourier transform infrared spectroscopy established the bonding and presence of various functional groups. The current study intends to fulfill the gap by exploring the removal of MG dye by ELM technique.

A fast and effective method for ammonium removal: Emulsion Liquid Membrane

In this study, ammonium was removed from an aqueous solution by using the Emulsion Liquid Membrane technique. The optimum values of the parameters that had effects on the removal process were determined and results were analyzed using statistical methods. As a result of the conducted experiments, it was determined that the volumetric ratio of the emulsion phase was 0.12, the effective internal phase source was H2SO4, the internal phase volumetric ratio was 0.42, the internal phase concentration was 0.36 N, the surfactant ratio was 2 %, the diluent ratio was 34/64 (mineral oil/toluene, %, v/v), homogenizer speed and time were 10,000 rpm and 1 min, agitation speed was 250 rpm, and external phase pH was 10.80. The fact that 98 % yield was achieved in a very short extraction time (15 s) under optimal conditions and the fact that the studies conducted on this subject in the literature are limited and different reveals the importance of this study obviously.

Dye removal with emulsion liquid membrane: experimental design and response surface methodology

ABSTRACT This work aims to removing anionic food dyes, Acid Red18 (E124) and Quinoline Yellow WS (E104), from their aqueous solutions. The Emulsion Liquid Membrane (ELM) technique was used. ELM consists of diluent (kerosene), nonionic surfactant (0.5 wt. % Triton X-45), Aliquat 336 as an extractant. Sulfuric acid (H2SO4) solution was used as an internal aqueous phase. The key parameters impacting the stability of liquid membrane and the efficiency of dye removal were investigated; Almost 98% of E124 at 50 mg/L are successfully extracted under optimum conditions. The extraction of a mixture of the two dyes at equal concentrations (25 mg/L) was conducted and their extraction showed more than 95% of efficiency. The experimental results of dye mixture (E124, E104) extraction were expressed by the following three quantities: The concentration of Triton X-45, the concentration of Aliquat 336, and the internal phase concentration of H2SO4, represented on three dimensional plots using the Box-Behnken design and the response surface methodology. For each of the parameters, the values of which were determined by experimental design, these results were subjected to empirical smoothing. The values, thus calculated, are consistent with the measurements.

Comparative study on effect of ionic liquids on static stability of green emulsion liquid membrane

The emulsion liquid membrane (ELM) technique is an economical and energy-efficient novel technique to extract a wide range of toxic pollutants, fermentation products, etc. The stability of ELM is the main hindrance in its applications in the large-scale industry. In addition to swelling or emulsion leakage as the leading cause of instability, another concern is the use of volatile organic solvents in the membrane phase, directly impacting the environment on numerous levels. To overcome the latter one, a new advanced and innovative green emulsion liquid membrane process (GELM) is being established by using vegetable oils as green solvents in place of volatile organic solvents in the membrane phase and ionic liquids are being incorporated into the emulsion to improve GELM stability. In the present work, the effect of different process constituents and operating parameters on GELM stability has been investigated by using ionic liquids. Further, GELM has been prepared by homogenizing the internal phase containing stripping agent and membrane phase containing surfactant, ionic liquid, and vegetable oils as solvent using an overhead agitator to analyze static stability. Under the optimized condition i.e., 0.1 [N] NaOH concentration in internal phase, 1.5% (v/v) Span 80 surfactant concentration, 0.1% (w/v) ionic liquid concentration, 0.4 (v/v) phase ratio, 2100 rpm emulsification speed and 20 min of emulsification time, 40% enhancement in static stability of GELM (upon utilizing Rice bran oil as solvent) has been obtained. GELM stability of 165 ± 1.5 min with ionic liquid in comparison to that of 120 ± 2 min without using an ionic liquid with no significant change/separation of GELM phases have been observed, which is sufficient for its further potential application for the extraction of toxic pollutant and reusability of GELM. Further, GELM obtained with ionic liquid and without ionic liquid had shown complete separation of phases after 20 h and 6 h, respectively.

Zinc extraction from a bioleaching solution by emulsion liquid membrane technique

Zinc separation from a bioleaching solution of a low-grade lead/zinc sulfide ore was performed by emulsion liquid membrane (ELM) technique. To study the extraction efficiency, the effect of key parameters including contact time, stirring speed, treat ratio, initial zinc concentration in the external phase, D2EHPA, Span80 and stripping agent concentration are studied and optimized. Maximum zinc extraction (≈71 %) was achieved at 20 min contact time, 150 rpm, 10 % (v/v) D2EHPA, 5 % (v/v) Span 80, 1.5 M sulfuric acid in the internal phase, and Vex/Vem = 5:1. The results showed that osmotic pressure gradient is responsible for water transport from the external phase into the internal phase and emulsion swelling in most cases. An excessive shear force, extra concentration of emulsion components and longer contact time trigger emulsion breakage and globule rupture.

Recovery of Manganese Ions from Aqueous Solutions with Cyanex 272 Using Emulsion Liquid Membrane Technique: A Design of Experiment Study

Recovery of Manganese Ions from Aqueous Solutions with Cyanex 272 Using Emulsion Liquid Membrane Technique: A Design of Experiment Study

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.

Propionic acid recovery from dilute aqueous solution by emulsion liquid membrane (ELM) technique: optimization using response surface methodology (RSM) and artificial neural network (ANN) experimental design

ABSTRACT Carboxylic acids are present in very dilute form in aqueous solutions which poses difficulty in its recovery. Emulsion liquid membrane (ELM) technique which integrates solvent extraction and stripping was experimentally explored for propionic acid recovery existent in very dilute aqueous solutions. The ELM process was carried out using trioctylamine (TOA) as a carrier in 1-decanol, sorbitan monooleate (Span 80) as a surfactant in heptane, and sodium carbonate (Na2CO3) as a stripping agent. The interactive effects of the different parameters on the propionic acid extraction efficiency were investigated. A comparative study utilizing Response surface methodology (RSM) and artificial neural network (ANN) was carried out. The statistical models were employed in the experimental design, optimization, construction and interpretation of response/output surface plots to analyze the effect of input variables on extraction efficiency. From the results obtained, both models gave statistically significant predictions of the response values. Results confirmation tests were completed to validate the predicted optimal operating conditions which include: propionic acid concentration = 0.082 kmol/m3, Na2CO3 concentration = 0.13 kmol/m3, fraction of TOA = 7.45%v/v, extraction time = 12 mins, treat ratio = 1.17 v/v with the experimental response. The optimum solution achieved by RSM led to an experimentally determined extraction efficiency of 92.28% which was in close proximity with the numerical predicted value of 93.68%.

Simultaneous Extraction of Lead, Copper, and Cadmium from Aqueous Solution using Emulsion Liquid Membrane Technique

A simultaneous extraction study of lead, copper, and cadmium from diluted aqueous solution through Emulsion Liquid Membrane (ELM) technique was conducted and extensive investigations of the impact of the pH of the feed phase, homogenizer speed, surfactant (Span 80) and carrier (D2EHPA) concentrations, and ratio of external to membrane phase on the system stability (breakage) and removal efficiencies of Pb2+, Cu2+,Cd2+ ions were experimentally carried out. Kerosene was used as the membrane and stabilized by Sorbitan monooleate (Span 80) as the emulsifier. Bis-2-Ethylhexyl phosphoric acid (D2EHPA) as an extractant and H2SO4 as a reagent (internal phase) were utilized. Lead, Copper, and Cadmium extraction efficiencies of 100%, 100%, and 98% were obtained respectively under specific operating conditions. The emulsion stability of the system was studied, and breakage of 1.8% under the best operating condition was obtained. High reagent (H2SO4) concentration (0.5 M) maintained the simultaneous extraction of the three heavy metals (lead, copper, and cadmium) and minimizes the probable interaction and competing mechanism between them in the extraction stage.

Investigation of experimental results and D-optimal design of hafnium ion extraction from aqueous system using emulsion liquid membrane technique

Hafnium metal is used in a wide range of industries such as microprocessor manufacturing, nuclear reactors and special alloys due to its physical, chemical and radiation properties. Emulsion liquid membrane (ELM) is an effective and efficient alternative for heavy metal separation compared to conventional methods due to high selectivity, energy-saving, high mass transfer and low operating capital. In this study, Cyanex 572 as a carrier, Span 85 as a surfactant, hydrochloric acid as an internal phase and kerosene as a diluent were used. In the first part of the study, the stability of the emulsions was investigated. The most stable emulsions were obtained by adding PIB polymer (3% w/v), Span 85 surfactant (3% w/v) and stirring for 15 min. In the second part, the separation of hafnium metal ions from aqueous solutions was investigated using ELM technique. The highest separation was obtained at 4% (v/v) as carrier concentration, 4% (w/v) as surfactant concentration, the membrane-to-feed volume ratio of 20/100 and W/O/W emulsion stirring rate and time equal to 400 rpm and 5 min, respectively. Moreover, to optimize the factors influencing the tests, the design of experiment (DOE) was performed using D-optimal method via Design Expert 10 software. Based on DOE results, the maximum extraction (> 99%) was achieved when the carrier concentration, the surfactant concentration, W/O/W emulsion stirring time, W/O/W emulsion stirring rate and emulsion volume/feed phase ratio were 4.49% v/v, 3.90% w/v, 11.49 min, 310.54 rpm and 2:1, respectively.

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.

Effect of Copper(II) and Cadmium(II) Ions Against the Percent Mercury Ion Extraction Using Emulsion Liquid Membrane Technique

The effect of copper(II) and cadmium(II) ions on the percent of mercury ion extraction using an emulsion liquid membrane technique have been performed. This study used HNO3 as an internal phase, mixed span 80 and span 20 as a surfactant, benzoyl acetone as cation carrier, kerosene as membrane phase, and mercury solution as a sample solution. Variations of concentrations of copper(II) and cadmium(II) ions added were 10, 20, and 30 ppm with mercury concentrations of 30 ppm. The result of the research showed that the addition of copper(II) ion with concentrations of 10 to 30 ppm decreased the percentage of mercury ion extraction 30 ppm by 12.12% and the addition of cadmium(II) ion with the concentration of 10 to 30 ppm decreased the percentage of mercury ion extraction 30 ppm by 11.74%.

Application of emulsion and Pickering emulsion liquid membrane technique for wastewater treatment: an overview.

According a wide range of relevant literature, the emulsion liquid membrane technique (ELM) is considered an efficient method to separate and recover organic and inorganic contaminants that could otherwise be released into the environment. One important limitation of ELM process concerns the stabilization and de-stabilization of emulsion globules. To address this, over the last few years, a new ELM trend known as the Pickering emulsion liquid membrane (PELM) has been developed. PELM involves nanoparticle concepts to achieve a more stable emulsion for wastewater treatment. In this article, ELM and PELM techniques, preparation methods, characteristics, stabilization methods (i.e., mechanical and ultrasound emulsification), and de-stabilization (i.e., swelling, leakage and coalescence) of the emulsion are reviewed and described. In addition, various parameters that could impact ELM stability, extraction, and recovery, such as emulsification speed and time, surfactant, carrier, internal agent, diluent, stirring speed, internal to membrane ratio, type of organic membrane, and treatment ratio, are also presented and discussed.