Transport of Zn (II) by TDDA-Polypropylene Supported Liquid Membranes and Recovery from Waste Discharge Liquor of Galvanizing Plant of Zn (II)

Ur Rehman, Hanif; Akhtar, Gul; Ur Rashid, Haroon; Ali, Nauman; Ahmad, Imtiaz; Ur Rehman, Saeed; Khan, Kamin; Arshad, Muhammad

doi:https://doi.org/10.1155/2017/7569354

Journal of Chemistry

On this page

Abstract Introduction Experimental Results and Discussion Conclusions Conflicts of Interest Acknowledgments References Copyright Related Articles

Research Article | Open Access

Volume 2017 | Article ID 7569354 | https://doi.org/10.1155/2017/7569354

Transport of Zn (II) by TDDA-Polypropylene Supported Liquid Membranes and Recovery from Waste Discharge Liquor of Galvanizing Plant of Zn (II)

Hanif Ur Rehman,¹Gul Akhtar,²Haroon Ur Rashid,¹Nauman Ali,²Imtiaz Ahmad,²Saeed Ur Rehman,²Kamin Khan,¹and Muhammad Arshad³

Academic Editor: Thijs A. Peters

Received11 Apr 2017

Revised30 Jul 2017

Accepted13 Aug 2017

Published02 Nov 2017

Abstract

The facilitated passage of Zn (II) across flat sheet supported liquid membrane saturated with TDDA (tri-n-dodecylamine) in xylene membrane phase has been investigated. The effect of acid and metal ion concentration in the feed solution, the carrier concentration in membrane phase, stripping agent concentration in stripping phase, and coions on the extraction of Zn (II) was investigated. The stoichiometry of the extracted species, that is, complex, was investigated on slope analysis method and it was found that the complex (LH)₂·Zn(Cl₂) is responsible for transport of Zn (II). A mathematical model was developed for transport of Zn (II), and the predicted results strongly agree with experimental ones. The mechanism of transport was determined by coupled coion transport mechanism with H⁺ and Cl⁻ coupled ions. The optimized SLM was effectively used for elimination of Zn (II) from waste discharge liquor of galvanizing plant of Zn (II).

1. Introduction

Over the past few decades, the prompt boost in the utilization of heavy metals has increased the flux of metallic ingredients into soils and natural water resources. The presence of even small amount of heavy metals in the environment is hazardous as the majority of them are harmful and persistent [1]. The zinc concentration in the earth crust is about 70 ppm. Zinc and its compounds have many applications and are used in galvanization, alloys, catalysts, wood preservation, vulcanization for rubber, photographic paper, ceramics, fertilizers, textiles, batteries, pigments and as dietary supplements and in medicines [2, 3].

About two billion people suffer from zinc deficiency in the developing countries and this thus causes various disorders in them. In minors, zinc deficiency is responsible for growth retardation, infection susceptibility, delayed sexual maturation, and diarrhea. These disorders lead to the deaths of about 800,000 children throughout the world every year.

Excess of zinc in the human body has been associated with system dysfunction which in turn can affect growth and reproduction. The presence of free zinc ion in solution has been reported to be very toxic for vertebrates, invertebrates, and plants [4–6]. Due to its toxic effect, large scale applications, and increasing demand for pure zinc, it is necessary to remove and separate zinc from industrial effluents.

Traditional techniques of recovery for metal ions, such as adsorption [7, 8], solvent extraction [9–12], precipitation [13], and ion exchange [14]. have normally low efficiency, require high capital and operating cost, and produce secondary pollution complications [15]. Among novel techniques suggested for transport of metal ions, supported liquid membrane is one of the promising methods. The technique comprises the applications of solvent extraction (high selectivity and distribution coefficient) while overcoming usual extraction’s shortcomings (loss of carrier due to emulsification and dispersion) [16–18].

Kanungo and Mohapatra [19] investigated the transport of Zn (II) through supported liquid membrane using bis(2,4,4-trimethylpentyl)phosphinic acid as a metal ion carrier. A model for the rate of transport of binary and ternary complex species has been discussed. The transport of Zn (II) via di-(2-ethylhexyl)phosphoric acid supported liquid membrane has been studied by Ata et al. [20]. The influence of pH of feed solution, carrier, and stripping agent concentration, temperature, and flow rate of feed and stripping solution on the transport of Zn (II) has been investigated. Wódzki and Szczepański found simultaneous recovery and bifurcation of Zn (II) and Cu (II) by means of two parallel BLMs. The two selective carriers, 5-nonylsalicylaldoxime and di-(2-ethylhexyl), were employed for transport of Zn (II) and Cu (II), respectively [21]. The selective removal of Zn (II) from other transition metals and transport across polymer inclusion membrane was investigated by Ulewicz and his coworkers [22]. It has been observed that transport selectivity of Zn (II) over Ni (II), Co (II), Cd (II), and Cu (II) decreases while increasing pH of the feed solution. Furthermore, it has been studied that Zn (II) can be selectively eliminated from dilute aqueous feed solution by solvent extraction. Kozlowska et al. studied the competitive transport of Zn (II), Cd (II), and Pb (II) through polymer inclusion membranes having organophosphorous acids as an ion carrier [23]. The nature of the extractants on cation efficiency and selectivity has been elaborated. Torz et al. reported the transport of Zn (II) from hydrochloric acid feed solution through hollow fiber modules using tributyl phosphate as a carrier [24]. It has been observed that the kinetics of the mass transfer process was restricted by the diffusion of species in the membrane openings. Lee et al. investigated the separation of zinc and copper by hollow fiber supported liquid membrane containing LIX 84 and PC-88A as mobile carriers. The influence of numerous operational factors on separation and permeation rate of Zn (II) and Cu (II) has been studied [25].

In our previous papers [26–29], an effort was made to design a model for transport of Ag (I), Mn (II), Pb (II), and Tl (III), through SLM using various carriers and diluents, and successfully applied to industrial waste effluents.

The present work elaborates the extraction and separation of Zn (II) from aqueous acidic feed solution through flat sheet supported liquid membrane using TDDA as a mobile carrier. In SLM studies, the influence of several process parameters like acid concentration in the feed solution, Zn (II) concentration in the feed solution, the carrier concentration in membrane phase, and NaOH concentration in strip solution on the Zn (II) flux was investigated. Another aim of current work was to investigate the species formed during the transport of Zn (II) and mechanism of Zn (II) and further to establish the stoichiometry of the chemical reactions through SLM. Furthermore, this study was concentrated to ascertain the most optimum conditions for transport of Zn (II), especially for its large scale separation and recovery from industrially galvanizing waste effluents of Zn (II). No such investigations have been done so far using TDDA SLM system for transport of Zn (II).

2. Theory

Transport of metal ion through SLM occurs by diffusion of metal-carrier complex via various basic steps. First, the metal ion diffuses across aqueous diffusion layer from aqueous bulk feed solution to membrane feed interface and the metal-carrier complex is prepared at feed membrane interface. The complex is then diffused through liquid membrane phase to strip membrane interface owing to the concentration gradient. The complex is finally dissociated at strip membrane interface, carrier returns back across liquid membrane phase, and metal ion diffuses through aqueous diffusion layer into bulk strip solution. The theoretical model of mass transfer of Zn (II) for this purpose is important for the diffusion of metal-carrier complex.

3. Experimental

3.1. Chemicals and Reagents

ZnCl₂ (97% BDH) in HCl (37% Merck) was used as feed in various concentration. NaOH (99-100% Merck) in distilled water in various concentrations was used as a stripping solution and TDDA (≥95% Merck) with diluent xylene (99.5%) to get the various composition of metal ion carrier. Double distilled and deionized water was used in all experiments. All other chemicals used were of analytical or better grade.

3.2. Analytical Instruments

Atomic absorption spectrometer of Perkin Elmer model 400 was used to measure the concentration of zinc (II) and other metal ions in feed and strip solutions. pH was determined through pH meter of Metrohm model 827. Viscosity determination of TDDA (in xylene) was performed via viscometer/rheometer of Brookfield LVDV-III.

3.3. Permeation Cell

The metal ion transport study was performed in two-compartment cell made of Perspex material as reported in our previous work [26]. Each half cell of the permeation cell had the volume capacity of 300 cm³ and active membrane area was 23.79 cm². Each half was equipped with synchronous motors, pH electrode, and sampling port. The stirring speed of 1500 rpm [26] was optimized for the similar type of permeation cell and carrier; therefore this stirring speed was used in all the permeation study. All the experiments were conducted at °C.

3.4. SLM Preparation

The microporous polypropylene thin coating of Celgard 2400 was applied as a solid support for a liquid organic carrier with an active pore size of 0.02 µm, the thickness of 25 µm, and porosity of 38%. The membrane was cut into rectangular pieces of cm and was soaked in the premeasured concentration of TDDA diluted with xylene in Petri dish for overnight. The membrane was then taken out from the organic solution. The excess amount of organic carrier and solvent were removed by allowing them to drain off the membrane for about five minutes.

3.5. SLM Transport Study

The membrane after preparation was placed in between the two compartments of the cell and screwed together to form a water tight seal. Both compartments of the cell were filled with 300 mL of predetermined concentration of feed and strip solutions. To avoid concentration polarization at feed and strip membrane interfaces, the two solutions in feed and strip compartments were continuously stirred. Samples were collected after a specific time interval from both feed and strip solution and tested for metal ion concentration. For most of the experiments, the carrier concentration was 0.80 mol/dm³ in xylene.

The flux () was calculated as follows [26]:

4. Results and Discussion

4.1. Reactions at Feed Membrane Interface

If tri-n-dodecylamine (TDDA) is represented by L, the following possibilities of reactions may take place. The tri-n-dodecylamine can be protonated to LH⁺ in acidic medium (HCl).It is supposed that ZnCl₂ in feed solution in the presence of excess chloride ions due to HCl is converted toThe cationic (LH⁺)(org) and anionic species then interact at feed membrane interface and form the complex asThe subscript org represents organic phase and aq aqueous phase and indicates the number of Cl⁻, H⁺, and L molecules associating with Zn (II) ions to form the neutral complex .

To express the contribution of H⁺ and Cl⁻, (3) may be represented as

4.2. Reactions at Strip Membrane Interface

The neutral complex formed at feed membrane interface as per (3)/(4) is extractable in liquid organic phase and disperses from feed membrane interface to strip membrane interface. The complex at strip membrane interface is dissociated owing to NaOH in the stripping phase as follows:The free carrier molecule (L) diffuses back through the liquid membrane phase towards feed membrane interface and again forms the complex. As per Wilke-Chang, the diffusion coefficient of the forward moving complex should be noticeably lesser than the diffusion coefficient of the backward moving free carrier molecules [30]. Owing to this reason, the free carrier concentration at feed membrane interface will constantly be higher than the complex. Figure 1 represents the schematic transport mechanism of Zn (II) through supported liquid membrane.

The equilibrium constant of (4) for Zn (II) can be written as follows:The distribution coefficient of Zn²⁺ () for distribution between the membrane and aqueous phases can be represented as follows: And on rearranging of (8),Now considering the extraction constant, distribution coefficient, and laws of diffusion via the same path as [29], it can be indicated as:Equation (11) shows that, at a constant temperature, the flux () of Zn (II) is directly proportional to the concentration of Cl⁻, H⁺, L, and . This equation can be used to find the number of H⁺ related to L in the form of LH⁺. This can be determined by various methods: one method is to keep [Cl⁻], [L], and constant in (11) and plotting against ; the slope of the curve will provide the “” value for a number of H⁺ ions in the complex. Likewise by drawing versus and maintaining [Cl⁻], [H⁺], and constant, the slope of the plot will give a number of moles () of TDDA contributing in complex formation of Zn (II).

4.3. Effect of Carrier Concentration

The carrier in the liquid membrane phase of the supported liquid membrane has a critical role in the extraction of metal ions by SLM [26]. Various concentrations of carrier ranging from 0.157 mol/dm³ to 1.103 mol/dm³ were used in solvent xylene to observe the effect of carrier concentration on the transport of Zn (II) through SLM. During this study, the Zn (II) concentration in feed solution was kept at mol/dm³ in 2.0 mol/dm³ of HCl and the NaOH concentration in strip solution was fixed at 2.0 mol/dm³.

Figure 2 shows that with the increase of carrier concentration from 0.157 to 0.80 mol/dm³ in xylene in the membrane phase has a significant effect on flux of Zn (II). It follows (11) where flux () is directly proportional to carrier concentration [L]. However, the flux is insignificant as the concentration of carrier increases beyond 0.80 mol/dm³. This reduction in transport of Zn (II) might be the result of enhanced friction of liquid membrane phase owing to high viscosity, as with the increase in carrier concentration, the viscosity of liquid membrane phase increases [29]. Hence 0.80 mol/dm³ of tri-n-dodecylamine was considered the optimum carrier concentration and more investigations were performed with this concentration of carrier.

Finding the number () of tri-n-dodecylamine (L) taking part in complex was determined by plotting versus as shown in Figure 3. The slope of the plot is 2.008, and this indicates that two molecules of TDDA take part in the complex formation.

In our previous study for the stability of membrane for such type of carrier, it has been observed that supported liquid membrane is quite stable for a period of 120 h with very minute flux variation in the metal ion flux and no indication of structural deformation of polypropylene membrane was investigated. Furthermore, the membrane was reused several times without leakage and metal ion flux decline [28].

4.4. Role of HCl Concentration in Feed Phase

The HCl performs an important part in the transportation of Zn (II) because it provides H⁺ and Cl⁻ for the formation of complex as per (4). The effect of HCl concentration on extraction Zn (II) was observed by varying the concentration of HCl in the range of 0.5 mol/dm³ to 3.0 mol/dm³, while keeping the concentration of TDDA in the liquid membrane phase at 0.80 mol/dm³ and concentration of NaOH on strip side at 2.0 mol/dm³. Figure 4 shows that as the concentration of HCl increases from 0.5 mol/dm³ to 2.0 mol/dm³ and the flux of Zn (II) increases. Thus, it can be concluded that with an increase of HCl concentration, the concentration of H⁺ and Cl⁻ ions in feed solution also increases. This, in turn, increases the formation of the complex as per (4), which ultimately enhances the transport of Zn (II). Although, by further increasing the concentration of HCl beyond 2.0 mol/dm³, the transport of Zn (II) decreases and this may be due to the formation of type species due to the large quantity of H⁺ and Cl⁻ in feed phase and reaction (4) is hindered in forward direction. This study shows that 2.0 mol/dm³ of HCl is the most favorable concentration for transport of Zn (II), and further studies were carried out with this concentration of HCl to evaluate various parameters for subsequent studies.

To investigate that how much hydrogen is taking part in complexation of Zn (II), was plotted versus (Figure 5). The slope of this plot was approximately 2.0, indicating that two hydrogens take part in a complex of Zn (II) transport. As the transport study concluded that two molecules of TDDA and H⁺ are involved in the complex formation of Zn (II), the complex formed during this extraction study may be .

4.5. Influence of Feed Concentration

To study the capability of this SLM for metal ion transport, various concentrations of Zn (II) from mol/dm³ to mol/dm³ were used in the feed solution. During this particular study, the concentrations of the carrier, stripping phase, and HCl in feed solution were kept at 0.80 mol/dm³, 2.0 mol/dm³, and 2.0 mol/dm³, respectively.

Figure 6 shows that as Zn (II) concentration in feed solution rises, the transport of Zn (II) also increases; this is as per (11), where flux () is directly proportional to feed concentration (). Such type behavior has already been studied in our previous study [27, 28]. This study shows that up to mol/dm³ no saturation of carrier with metal ion takes place.

4.6. Influence of Stripping Phase Concentration

The stripping agent dissociates the complex at strip membrane interface and releases Zn (II) in strip solution. To investigate the effect of NaOH on the transport of Zn (II), numerous concentrations of NaOH in the range of 0.05 mol/dm³ to 2.5 mol/dm³ were used, while keeping the TDDA concentration at 0.80 mol/dm³ and HCl concentration in feed solution at 2.0 mol/dm³.

Figure 7 shows that as the concentration of NaOH rises from 0.05 mol/dm³ to 0.1 mol/dm³, the flux of Zn (II) decreases and, beyond this concentration of NaOH, the flux of Zn (II) increases. The decrease in transport of Zn (II) at a lower concentration of NaOH can be explained that it forms a precipitate of Zn(OH)₂ which is insoluble and blocks the pores of polypropylene membrane and transport of Zn (II) is restricted [31]. The SEM (Figure 8(b)) indicates the blocked SLM at a lower concentration of NaOH. More increase in the concentration of NaOH increases the transportation of Zn (II), as the precipitate of Zn (OH)₂ is soluble in excess of NaOH and more OH⁻ are available that enhance the decomposition of the complex at strip membrane interface as per (5).

(a) SEM of the membrane before Zn (II) transport

(b) SEM of membrane at 0.1 mol/dm3 of NaOH ([HCl] in feed solution = 2.0 mol/dm3, [TDDA] in membrane phase = 0.80 mol/dm3, [Zn (II)] = mol/dm3).

(b) SEM of membrane at 0.1 mol/dm³ of NaOH ([HCl] in feed solution = 2.0 mol/dm³, [TDDA] in membrane phase = 0.80 mol/dm³, [Zn (II)] = mol/dm³).

5. Recovery of Zinc (II) from Waste Discharge/Effluent of Galvanizing Plant

The objective of this work was to design and develop SLM for recovery of Zn (II) from industrial waste effluents. The polypropylene as supported liquid membrane, TDDA as a carrier, was utilized for extraction of Zn (II) from waste discharge liquor of galvanizing plant. To check and assess the efficiency of SLM system, samples of galvanized industrial waste were collected from the different locations of the drain carrying the galvanizing industrial effluent. The effluent samples were analyzed using the aforementioned method as described in Experimental and the percent extraction and recovery of the Zn(II) metal ions were determined using atomic absorption spectrophotometry method. The data obtained is provided in Figure 9 which indicates approximately the complete extraction and recovery of Zn (II) after 210 minutes. This shows the suitability and effectiveness of this SLM for recovery of Zn (II).

6. Recovery and Transport of Zn(II) from Galvanizing Plant Waste

The present SLM was designed for the transport of Zn(II) metal ions and applied to zinc industrial effluents of galvanizing plants because zinc is one of the industrial important metals because of its applications and its use for protection, passivation, and decoration of some heavy elements. The data in Table 2 show that TDDA-polypropylene SLM system has significant transport efficiency for Zn(II) metal ions, that is, about 99.8%, while other metal ions like Co, Cu, Cd, Mn, Cr, and Fe show very little or more precisely negligible amount of transport that is 0.0 to 0.72% or in average 0.08% for Co, 0.23% for Cu, 0.15% for Cd, 0.36% for Mn, 0.06% for Cr, and 0.28$ for Fe. This much smaller amount of transport may be attributed to experimental error. If error factor is taken into account then TDDA-polypropylene SLM system is highly selective for transport of Zn(II) metal ions only. The data are represented in Tables 1 and 2.

7. Conclusions

The flux () got increased by increasing carrier concentration up to 0.80 mol/dm³, and, further increasing the carrier concentration, the transport of Zn (II) was found to decrease. The Zn(II) ions transport was increased by increasing HCl concentration in feed solution up to 2.0 mol/dm³ and then decreased using a higher concentration of HCl. The slope analysis studies of of Zn (II) versus and showed that 2.0 mole of each tri-n-dodecylamine and hydrogen are involved in the transport of Zn (II). The maximum transport of Zn (II) was achieved at 0.80 mol/dm³ of TDDA in membrane phase and 2.0 mol/dm³ of HCl and NaOH in feed and strip solution, respectively. It was also found to be coupled coion extraction pathway, as H⁺, Cl⁻, and Zn (II) travel in the same direction. Two moles of hydrogen and TDDA interact with one mole of Zn (II) producing a complex , that is responsible for transport of Zn (II). This SLM system was effectively used for removal of Zn (II) to the waste discharge liquor of galvanizing plant of zinc.

Conflicts of Interest

The authors declare that there are no conflicts of interest regarding the publication of this paper.

Acknowledgments

The authors acknowledge Sarhad University of Science and Information Technology, Peshawar, KPK, Pakistan, for providing financial assistance to accomplish this work.

References

R. A. Wuana and F. E. Okieimen, “Heavy metals in contaminated soils: a review of sources, chemistry, risks and best available strategies for remediation,” ISRN Ecology, vol. 2011, Article ID 402647, 20 pages, 2011.
View at: Publisher Site | Google Scholar
D. W. Thomas, Metals and Their Compounds in the Environment, Edited by E. Merian, Wiley, Weinheim, Germany, 1991.
ATSDR (Agency for Toxic Substances and Disease Registry), Toxicological Profile for Zinc, Public Health Service. U.S. Department of Health and Human Services, Atlanta, Ga, USA, 2005.
A. S. Prasad, “Zinc deficiency,” The British Medical Journal, vol. 326, no. 7386, pp. 409-410, 2003.
View at: Publisher Site | Google Scholar
K. M. Hambidge and N. F. Krebs, “Zinc deficiency: a special challenge,” Journal of Nutrition, vol. 137, no. 4, pp. 1101–1105, 2007.
View at: Google Scholar
G. J. Fosmire, “Zinc toxicity,” American Journal of Clinical Nutrition, vol. 51, no. 2, pp. 225–227, 1990.
View at: Google Scholar
L. Monser and N. Adhoum, “Modified activated carbon for the removal of copper, zinc, chromium and cyanide from wastewater,” Separation and Purification Technology, vol. 26, no. 2-3, pp. 137–146, 2002.
View at: Publisher Site | Google Scholar
S. Liang, X. Guo, and Q. Tian, “Adsorption of Pb²⁺ and Zn²⁺ from aqueous solutions by sulfured orange peel,” Desalination, vol. 275, no. 1–3, pp. 212–216, 2011.
View at: Publisher Site | Google Scholar
F. J. Alguacil and S. Martínez, “Solvent extraction of Zn(II) by cyanex 923 and its application to a solid-supported liquid membrane system,” Journal of Chemical Technology and Biotechnology, vol. 76, no. 3, pp. 298–302, 2001.
View at: Publisher Site | Google Scholar
K. C. Sole, T. L. Ferguson, and J. B. Hiskey, “Solvent extraction of silver by cyanex 272, cyanex 302 and cyanex 301,” Solvent Extraction and Ion Exchange, vol. 12, no. 5, pp. 1033–1050, 1994.
View at: Publisher Site | Google Scholar
P. M. Cole and K. C. Sole, “Zinc solvent extraction in the process industries,” Mineral Processing and Extractive Metallurgy Review, vol. 24, no. 2, pp. 91–137, 2003.
View at: Publisher Site | Google Scholar
M. S. Lee and S.-H. Nam, “Solvent extraction of zinc from strong hydrochloric acid solution with Alamine336,” Bulletin of the Korean Chemical Society, vol. 30, no. 7, pp. 1526–1530, 2009.
View at: Publisher Site | Google Scholar
F. M. Pang, S. P. Teng, T. T. Teng, and A. K. M. Omar, “Heavy metals removal by hydroxide precipitation and coagulation-flocculation methods from aqueous solutions,” Water Quality Research Journal of Canada, vol. 44, pp. 1–9, 2009.
View at: Google Scholar
S. V. Plokhov, I. G. Matasova, V. A. Utkin, and V. Y. Vodzinskii, “Specific features of ion-exchange zinc(II) extraction from washing water of zinc plating,” Russian Journal of Applied Chemistry, vol. 75, no. 6, pp. 950–953, 2002.
View at: Publisher Site | Google Scholar
K. H. Park, P. K. Parhi, and N.-H. Kang, “Studies on the removal of low content copper from the sea nodule leach liquor using the cationic resin TP 207,” Separation Science and Technology, vol. 47, no. 10, pp. 1531–1541, 2012.
View at: Publisher Site | Google Scholar
J. D. Gyves and E. R. San Miguel, “Metal ion separations by supported liquid membranes,” Industrial and Engineering Chemistry Research, vol. 38, no. 6, pp. 2182–2202, 1999.
View at: Publisher Site | Google Scholar
V. V. Prasad, D. J. Yogesh, D. S. Ajay et al., “Simultaneous extraction of neodymium and uranium using hollow fiber supported liquid membrane,” Separation Science and Technology, vol. 49, no. 10, pp. 1509–1520, 2014.
View at: Publisher Site | Google Scholar
B. Mokhtari and K. Pourabdollah, “Inclusion separation of alkali metals in emulsion liquid membranes by nanobaskets of calix[4]crown-3,” Brazilian Journal of Chemical Engineering, vol. 29, no. 4, pp. 783–793, 2012.
View at: Publisher Site | Google Scholar
S. B. Kanungo and R. Mohapatra, “Coupled transport of Zn (II) through a supported liquid membrane containing bis (2,4,4-trimethyl pentyl) phosphinic acid in kerosene. 1. A model for the rate process involving binary and ternary complex species,” Journal of Membrane Science, vol. 105, pp. 217–226, 1995.
View at: Google Scholar
O. N. Ata, A. V. Beşe, S. Çolak, B. Dönmez, and A. Çakıcı, “Effect of parameters on the transport of zinc ion through supported liquid membrane,” Chemical Engineering and Processing: Process Intensification, vol. 43, no. 7, pp. 895–903, 2004.
View at: Publisher Site | Google Scholar
R. Wódzki and P. Szczepański, “Simultaneous recovery and separation of Zn²⁺ and Cu²⁺ in hybrid membrane systems,” Separation and Purification Technology, vol. 41, no. 3, pp. 289–297, 2005.
View at: Publisher Site | Google Scholar
M. Ulewicz, W. Walkowiak, J. Gega, and B. Pospiech, “Zinc (II) selective removal from other transition metal by solvent extraction and transport through polymer inclusion membranes with D2EHPA,” Ars Separatoria Acta, vol. 2, pp. 47–55, 2003.
View at: Google Scholar
J. Kozlowska, C. A. Kozłowski, and J. J. Koziol, “Transport of Zn(II), Cd(II), and Pb(II) across CTA plasticized membranes containing organophosphorous acids as an ion carriers,” Separation and Purification Technology, vol. 57, no. 3, pp. 430–434, 2007.
View at: Publisher Site | Google Scholar
M. Torz, K. Alejski, and J. Szymanowski, “Modelling of zinc (II) extraction from model hydrochloric acid solutions in hollow fiber modules,” Physicochemical Problems of Mineral Processing, vol. 37, pp. 97–105, 2003.
View at: Google Scholar
J.-C. Lee, J. Jeong, B.-S. Kim, M. S. Kim, and M. Kobayashi, “Separation of copper and zinc ions by hollow fiber supported liquid membrane containing LIX84 and PC-88A,” Materials Transactions, vol. 45, no. 6, pp. 1915–1919, 2004.
View at: Publisher Site | Google Scholar
S. U. Rehman, G. Akhtar, M. A. Chaudry, N. Bukhari, Najeebullah, and N. Ali, “Mn (VII) ions transport by triethanolamine cyclohexanone based supported liquid membrane and recovery of Mn (II) ions from discharged zinc carbon dry battery cell,” Journal of Membrane Science, vol. 366, no. 1-2, pp. 125–131, 2011.
View at: Publisher Site | Google Scholar
S. U. Rehman, G. Akhtar, and M. A. Chaudry, “Coupled transport of Tl³⁺ through triethanolamine-xylene-polypropylene supported liquid membranes,” Journal of Industrial and Engineering Chemistry, vol. 18, no. 1, pp. 492–498, 2012.
View at: Publisher Site | Google Scholar
S. U. Rehman, G. Akhtar, M. A. Chaudry, K. Ali, and N. Ullah, “Transport of Ag⁺ through tri-n-dodecylamine supported liquid membranes,” Journal of Membrane Science, vol. 389, pp. 287–293, 2012.
View at: Publisher Site | Google Scholar
S. Ur Rehman, G. Akhtar, and M. A. Chaudry, “Coupled transport of Pb²⁺ through tri-n-octylamine-xylene-polypropylene supported liquid membranes,” Canadian Journal of Chemical Engineering, vol. 91, no. 6, pp. 1140–1152, 2013.
View at: Publisher Site | Google Scholar
S. A. Ansari, P. K. Mohapatra, and V. K. Manchanda, “Recovery of actinides and lanthanides from high-level waste using hollow-fiber supported liquid membrane with TODGA as the carrier,” Industrial and Engineering Chemistry Research, vol. 48, no. 18, pp. 8605–8612, 2009.
View at: Publisher Site | Google Scholar
F. Holleman, A. E. Wiberg, and N. Wiberg, Zink, Lehrbuch der Anorganischen Chemie, Walter de Gruyter, Berlin, Germany, 91th–100th edition, 1985.

Copyright

Copyright © 2017 Hanif Ur Rehman et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

1133

Downloads

887

Citations