Study on ultrasonically assisted emulsification and recovery of copper(II) from wastewater using an emulsion liquid membrane process (original) (raw)
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Jordanian Journal of Engineering and Chemical Industries, 2021
This work aims to optimize the parameters that affect the stability of a W/O emulsion to exploit it in the extraction of heavy metals contained in the liquid effluents. The study of the emulsion stability shows that; an emulsification time of 10 minutes, a surfactant concentration of Span80 equal to 3% (w/w), an extractant concentration of Triethylamine N(CH2CH3)3 equal to 5% (w/w), an internal phase concentration of phosphoric acid (H3PO4) of 0.75M, a volume ratio of membrane phase to internal phase of 1, a volume ratio of external phase to the emulsion of 20 and a stirring speed of 180 rpm; lead to the formation of a very stable emulsion with a very low rupture rate of around 1.92% after one hour of contact time. The results of extraction of copper ions revealed that under the best operational conditions, the extraction yield was closed to 93.33% for 20% extractant content, a contact time of 12 minutes, and an initial concentration of copper ions of 400 ppm. The application of this new membrane matrix based on phosphoric acid used as inner phase, sorbitan monooleate as a surfactant, and Triethylamine as extractant has been proven effective for extracting copper ions in water.
Separation and Purification Technology, 2008
The main objective of this work is the utilization of W/O emulsions prepared by low-frequency ultrasonic irradiation (22.5 kHz) for the removal and recovery of cationic dyes from aqueous solution by emulsion liquid membrane containing di(2-ethylhexyl) phosphoric acid (D2EHPA) as carrier. The important parameters governing the extraction behavior of dyes have been investigated. These parameters were contact time of the external phase with W/O emulsions, external phase concentration, feed phase pH, stirring speed, extractant concentration, presence of salts, and type of diluent. The extraction of a mixture of four cationic dyes (methylene blue, rhodamine B, malachite green, and basacryl red GL) is also investigated in the absence and presence of salt in the external phase. The possibility of stripping the dyes is evaluated and the influence of sulfuric acid concentration on the stripping efficiency is also examined. The obtained results show that, under most favorable conditions, practically all the dye cations present in the feed phase were extracted. The removal percentage of the mixed dye was found to be higher than 98% even in the presence of salt in the continuous phase. The transport mechanism of cationic dyes for the present system was determined and divided into six stages. The best sulfuric acid concentration in the internal phase that conducted to very good stripping efficiency (≥97%) and excellent emulsion stability was 0.5 M. In all cases, the recovery of the membrane phase was total and the extraction of dyes was not decreased up to seven runs.
Removal of copper ions from a waste mine water by a liquid emulsion membrane method
Minerals Engineering, 2005
This is a communication on the removal of copper(II) ions from a residual mine water using an emulsified liquid membrane (ELM). The membrane was prepared by dissolving the extractant LIX-860 (a salicylaldoxime), used as a mobile carrier, and Span-80, a surfactant, in kerosene. The ELM allowed an efficient metal transport from the feed solution towards the strip liquor, in experiments carried out in a batch-type stirred tank at 30°C. A screening factor-type experimental statistical design was developed, which established the variables and their interrelation affecting the studied process. The experimental results and the variance analysis indicated that the statistically significant variables on copper transport through the membrane were the extractant concentration, the stirring time and the stirring speed of the double emulsion. The surfactant concentration range employed in this study adequately stabilized the membrane. However, it did not produce any positive effect on metal extraction. It was observed that the use of an excessively high content of surfactant produced lower metal transport extraction since it gave rise to a higher interfacial resistance. The experimental results reported show the potential for removal of valuable or toxic metals from dilute mine solutions using an extractor based on emulsified liquid membranes.
Chemical Engineering & Technology, 2008
The separation of zinc and copper ions from sulfuric acid solutions by an emulsion liquid membrane (ELM), using di-(2-ethylhexyl) phosphoric acid (D2EHPA) as a carrier, has been investigated. The batch extraction of zinc and copper was carried out while varying a selection of experimental conditions, i.e., stirring speed, treatment ratio, concentrations of metal ions in the feed phase, carrier and Span 80 concentration in the membrane, and internal phase concentration. The results obtained demonstrate the effectiveness of D2EHPA as a carrier for the separation of zinc and copper from sulfuric acid media using an ELM. An increase of the D2EHPA concentration beyond 2 vol.-% does not result in the improved extraction of zinc because the viscosities of the membrane and emulsion have a trend to increase for higher carrier concentrations. It was found that the extraction rate of copper was affected by the carrier concentration in the liquid membrane and by the pH and metal content in the external phase. A 3 vol.-% concentration of surfactant in the organic phase was required to stabilize the emulsion. The number of stages required for the extraction of zinc and copper by an ELM was determined from McCabe-Thiele plots.
Study of Copper Recovery Using Emulsion Liquid Membrane under Taylor-Couette Column
KnE Social Sciences, 2019
High demand on batik fabric significantly increased wastewater volume from batik home industries. Copper, being used as mordanting agent, available in the highest concentration in industrial textile wastewater. Emulsion liquid membrane (ELM) is promising selective method to recover solute. Taylor-Couette column (TCC) was proposedtoextractcopperinsteadofusingconventionalreactorthatdisturbsemulsion stability. Experiment was done by varying volume ratio of emulsion to feed phase, carrier and internal phase concentration. Extraction efficiency of>98% was obtained at volume ratio of emulsion to feed phase of 1:5, carrier concentration of 4 wt. %, and internal phase concentration of 0.1 M, respectively
Factors influencing the ultrasonic separation of oil-in-water emulsions
Ultrasonics Sonochemistry, 2005
Ultrasound may have inherent shortcomings that preclude its ability to coagulate grease from wastewater, yet these may be overcome by the simultaneous application of electrolysis. We studied the role of pH, conductivity, temperature, ultrasound intensity and duration, and electrolysis voltage, current, and duration, in the study treatment. Conductivity was found to be the most significant factor, however interactions among the eight study variables are likely more important than individual factors. The proposed process was capable of removing up to 100% of grease from the studied wastewater.
Separation and Purification Technology, 2000
Emulsion Liquid Membrane (ELM) is a separation technique, which requires organic solvent, extractant and surfactant for its formulation. All the components play important roles. Surfactant adds stability to the emulsion but at higher concentration lowers extraction rate. Some surfactants, known as bi-functional surfactants, have dual properties of an extractant and an emulsifier. Use of such surfactant may eliminate the addition of an extractant to ELM system. In this study, polyethylene glycol was used as bi-functional surfactant in an ELM process for the extraction of metal ions from a ternary (copper, nickel and cobalt) aqueous solution. Dichloroethane, ammonium thiocyanate and potassium hydroxide were used as solvent, ligand and stripping agent, respectively. The paper presents the results on the characterization of the reactions (stoichiometry and reaction order) obtained through equilibrium and kinetic studies along with some batch emulsion extraction results.
Application of Liquid Emulsion Membrane
—In the present work, emulsion liquid membrane (ELM) technique was applied for the extraction of cadmium(II) present in aqueous samples. Aliquat 336 (Chloride tri-N-octylmethylammonium) was used as carrier to extract cadmium(II). The main objective of this work is to investigate the influence of various parameters affected the ELM formation and its stability and testing the performance of the prepared ELM on removal of cadmium by using synthetic solution with different concentrations. Experiments were conducted to optimize pH of the feed solution and it was found that cadmium(II) can be extracted at pH 6.5. The influence of the carrier concentration and treat ratio on the extraction process was investigated. The obtained results showed that the optimal values are respectively 3% (Aliquat 336) and a ratio (feed: emulsion) equal to 1:1.
Chemical Engineering Science, 2007
In this paper, a new liquid membrane technique, hollow fiber renewal liquid membrane (HFRLM), is presented, which is based on the surface renewal theory, and integrates the advantages of fiber membrane extraction, liquid film permeation and other liquid membrane processes. The results from the system of CuSO 4 + D2EHPA in kerosene + HCl show that the HFRLM process is very stable. The liquid membrane is renewed constantly during the process, the direct contact of organic droplets and aqueous phase provides large mass transfer area. These effects can significantly reduce the mass transfer resistance in the lumen side. Then the mixture of feed phase and organic phase flowing through the lumen side gives a higher mass transfer rate than that of stripping phase and organic phase, because the aqueous layer diffusion of feed phase is the rate-controlling step. The overall mass transfer coefficient increases with increasing flow rates and D2EHPA concentration in the organic phase, and with decreasing initial copper concentration in the feed phase. The overall mass transfer coefficient also increases with increasing pH in the feed phase, and reaches a maximum value at pH of 4.44, then decreases. Also, there is a favorable w/o volume ratio of 20:1 to 30:1 for this process. Compared with hollow fiber supported liquid membrane and hollow fiber membrane extraction processes, HFRLM process has a high mass transfer rate. Mathematical model for the HFRLM process based on the surface renewal theory is developed. The calculated results are in good agreement with experimental results under the conditions studied.