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A new emulsion liquid membrane based on a palm oil for the extraction of heavy metals.

Björkegren S, Karimi RF, Martinelli A, Jayakumar NS, Hashim MA - Membranes (Basel) (2015)

Bottom Line: Our results demonstrate that this novel ELM formulation, using the vegetable palm oil as diluent, is useful for the removal of hexavalent chromium with an efficiency of over 99% and is thus competitive with the already existing, yet less environmentally friendly, ELM formulations.This result was achieved with an optimal concentration of 0.1 M NaOH as stripping agent and an external phase pH of 0.5.Different water qualities have also been investigated showing that the type of water (deionized, distilled, or tap water) does not significantly influence the extraction rate.

View Article: PubMed Central - PubMed

Affiliation: Applied Surface Chemistry, Chemical and Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden. sanna.bjorkegren@chalmers.se.

ABSTRACT
The extraction efficiency of hexavalent chromium, Cr(VI), from water has been investigated using a vegetable oil based emulsion liquid membrane (ELM) technique. The main purpose of this study was to create a novel ELM formulation by choosing a more environmentally friendly and non-toxic diluent such as palm oil. The membrane phase so formulated includes the mobile carrier tri-n-octylmethylammonium chloride (TOMAC), to facilitate the metal transport, and the hydrophilic surfactant Tween 80 to facilitate the dispersion of the ELM phase in the aqueous solution. Span 80 is used as surfactant and butanol as co-surfactant. Our results demonstrate that this novel ELM formulation, using the vegetable palm oil as diluent, is useful for the removal of hexavalent chromium with an efficiency of over 99% and is thus competitive with the already existing, yet less environmentally friendly, ELM formulations. This result was achieved with an optimal concentration of 0.1 M NaOH as stripping agent and an external phase pH of 0.5. Different water qualities have also been investigated showing that the type of water (deionized, distilled, or tap water) does not significantly influence the extraction rate.

No MeSH data available.


The graph shows the abundance of Cr(VI) ions in water with varying pH. For slightly acidic or basic pH, CrO42− is the dominating form, a further decrease in pH leads to the formation of HCrO42− and H2CrO4. Data reproduced from [20].
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membranes-05-00168-f004: The graph shows the abundance of Cr(VI) ions in water with varying pH. For slightly acidic or basic pH, CrO42− is the dominating form, a further decrease in pH leads to the formation of HCrO42− and H2CrO4. Data reproduced from [20].

Mentions: Chemistry of chromium (VI) and TOMAC. The species of chromium present in an aqueous solution depend to a large extent on the pH of the solution and the ionic strength. This dependence is graphically shown in Figure 4 for solutions in water. TOMAC was chosen for carrier to achieve an efficient removal since this ionic liquid possesses appropriate properties such as high solubility in the organic phase and low solubility in the aqueous phase, and in addition has previously shown to efficiently extract Cr(VI) [5].


A new emulsion liquid membrane based on a palm oil for the extraction of heavy metals.

Björkegren S, Karimi RF, Martinelli A, Jayakumar NS, Hashim MA - Membranes (Basel) (2015)

The graph shows the abundance of Cr(VI) ions in water with varying pH. For slightly acidic or basic pH, CrO42− is the dominating form, a further decrease in pH leads to the formation of HCrO42− and H2CrO4. Data reproduced from [20].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4496638&req=5

membranes-05-00168-f004: The graph shows the abundance of Cr(VI) ions in water with varying pH. For slightly acidic or basic pH, CrO42− is the dominating form, a further decrease in pH leads to the formation of HCrO42− and H2CrO4. Data reproduced from [20].
Mentions: Chemistry of chromium (VI) and TOMAC. The species of chromium present in an aqueous solution depend to a large extent on the pH of the solution and the ionic strength. This dependence is graphically shown in Figure 4 for solutions in water. TOMAC was chosen for carrier to achieve an efficient removal since this ionic liquid possesses appropriate properties such as high solubility in the organic phase and low solubility in the aqueous phase, and in addition has previously shown to efficiently extract Cr(VI) [5].

Bottom Line: Our results demonstrate that this novel ELM formulation, using the vegetable palm oil as diluent, is useful for the removal of hexavalent chromium with an efficiency of over 99% and is thus competitive with the already existing, yet less environmentally friendly, ELM formulations.This result was achieved with an optimal concentration of 0.1 M NaOH as stripping agent and an external phase pH of 0.5.Different water qualities have also been investigated showing that the type of water (deionized, distilled, or tap water) does not significantly influence the extraction rate.

View Article: PubMed Central - PubMed

Affiliation: Applied Surface Chemistry, Chemical and Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden. sanna.bjorkegren@chalmers.se.

ABSTRACT
The extraction efficiency of hexavalent chromium, Cr(VI), from water has been investigated using a vegetable oil based emulsion liquid membrane (ELM) technique. The main purpose of this study was to create a novel ELM formulation by choosing a more environmentally friendly and non-toxic diluent such as palm oil. The membrane phase so formulated includes the mobile carrier tri-n-octylmethylammonium chloride (TOMAC), to facilitate the metal transport, and the hydrophilic surfactant Tween 80 to facilitate the dispersion of the ELM phase in the aqueous solution. Span 80 is used as surfactant and butanol as co-surfactant. Our results demonstrate that this novel ELM formulation, using the vegetable palm oil as diluent, is useful for the removal of hexavalent chromium with an efficiency of over 99% and is thus competitive with the already existing, yet less environmentally friendly, ELM formulations. This result was achieved with an optimal concentration of 0.1 M NaOH as stripping agent and an external phase pH of 0.5. Different water qualities have also been investigated showing that the type of water (deionized, distilled, or tap water) does not significantly influence the extraction rate.

No MeSH data available.