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Facilitated transport of germanium from acidic medium through supported liquid membrane using Cyanex 301 as mobile carrier

Kamran Haghighi Hossein, Irannajad Mehdi, Moradkhani Davood

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 1

225--236

EN

In this research, a flat sheet supported liquid membrane (FSSLM) system was used to transfer germanium from the acidic medium. The poly-tetra fluoro ethylene (PTFE) membrane filter with the hydrophobic nature and Cyanex 301 were selected as the support and the mobile carrier, respectively. The influence of various parameters being pH of the feed solution (1.5-5), germanium concentration (10-40 mg/dm3), carrier concentration in the solid membrane (10-40 vol%), and sulfuric acid concentration of the receiving phase (100-400 g/dm3) was investigated on the transport of germanium. Under the optimum condition being pH of 1.5, the germanium concentration of 40 mg/dm3, the carrier concentration of 1.18 mol/dm3, and the sulfuric acid concentration of 400 g/dm3, a mass transfer model was developed. Based on this model, the transport mechanism, diffusion of species to the feed-membrane interface, the chemical reaction of species and Cyanex 301, and diffusion of germanium-Cyanex 301 complexes across SLM were explained. According to the obtained model, the values of 6.57 and 738.6 s/cm were achieved for the aqueous and organic diffusion resistances, respectively.

2

Removal of methylene blue dye from wastewater by using supported liquid memberane technology

Ashraf M. W.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 2

26--30

EN

The present work describes the application of Supported Liquid Membrane (SLM) technology towards the removal and recovery of a cationic dye (Methylene Blue) from aqueous solutions. Natural and non-toxic vegetable oils have been impregnated on microporous polymeric films of polyvinylidene fluoride (PVDF) to constitute a liquid membrane. Different parameters affecting the transport, like pH of feed solution, acid concentration in the strip solution, initial dye concentration, oil types and stirring speeds have been investigated. Highest value of flux (1.7 x 10–5 mg/cm2/sec1) for methylene blue dye was achieved with sunflower oil impregnated on the PVDF support, with pH maintained at 12 in the feed solution and 0.3 M hydrochloric acid concentration in the strip solution. It took 6 hours to transport maximum amount of dye under optimum conditions.

3

The Elimination of Cadmium(II) from Aqueous Environment by Supported Liquid Membrane Method Using the Basic Carrier

Ashraf M. W., Bukhari A.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 1

19-30

EN

The transport of cadmium ions through a supported liquid membrane containing triethanolamine (TEA) as a mobile carrier has been studied. The effects of Cd(II) concentration, HCl in feed and car rier con cen tra tion in mem brane have been stud ied. Cd(II) con - cen tra tion in crease in feed leads to an increase influx from 2.1´10-7 to 8.4´10-7 mol cm-2 sec-1 within Cd(II) ions concentration range (2.7´10-4 M - 16.3´10-4 M) at 2.0 M HCl in the feed and 3.0 M triethanolamine in the membrane. Increase in H+ ion concentration from 0.5 M to 3.0 M results in an increase in Cd(II) ions flux but a decrease is observed beyond 2.0 M HCl concentration in feed. Increase in carrier concentration in the liquid inside the membrane enhances the flux with its maxima at 3.0 M carrier. Further increase in the concentration of TEA leads to a decrease in transport due to increase in viscosity of membrane liquid. The optimum conditions for Cd(II) ions transport are, 2.0 M HCl in feed, 3.0 M TEA in membrane and 0.1 M NaOH as strip solution. Similar transport characteristics have been observed for Cd-EDTA complexed anions across TEA- cyclo - hexanone based SLM, thus indicating a cadmium anion transport coupled with protons and chloride or EDTA co-ions.