High concentration of chloride ions in continental water is a great problem for the exploitation of these natural resources. In industry, the use of this water involves additional conditioning steps. For drinking water and irrigation uses, the Cl- must be reduced by conventional water treatment processes, like ion exchange or reverse osmosis, but for large scale production these techniques could be very expensive due to resin regeneration or energy costs. The possibility of using supported liquid membranes (SLM) with ionic liquids (IL), Aliquat 336, Cyphos IL 101 and Cyphos IL 167, as carriers to exchange Cl- for HCO3- anion has been shown to work. The reversibility of this anion exchange was corroborated by solvent extraction experiments and implemented in flat sheet supported liquid membrane (FSSLM) and hollow fiber renewal liquid membrane technologies (HFRLM). About double transport values have been obtained in HFRLM compared to SLM and 1 h is the time enough to reduce the chloride concentration up to 250 mg/L using HFRLM at the best experimental condition. The results obtained allow us to be optimistic about the implementation of this technology on a large scale to chloride reduction in drinking water when the source is inadequate for direct use. (C) 2013 Elsevier B.V. All rights reserved.
Líquido iónico para la extracción de compuestos de boro y composición y procedimientos correspondientes. Se presenta la síntesis de unos nuevos líquidos iónicos obtenidos por la reacción de haluros de alquilo con aminas primarias con sustituyentes 1,3-diólicos y su uso específico para la separación selectiva de boro aplicable en plantas desalinizadoras de agua de mar mediante tecnología de membranas líquidas soportadas. Este procedimiento es extensible a cualquier efluente acuoso del que se requiera la eliminación de boro.
Abstract: BACKGROUND: Among the polyols, 1,3 diols are selective and efficient extractants for boron but significant solubility of these into aqueous solutions restricts their application in large scale separation processes. Solvent modifiers can be used to reduce extractant loss to the aqueous phase. Efficiency of the diolic extractants for boron separation have been tested in the presence of different solvent modifiers. RESULTS: Compared with other modifiers studied, decanol gives better stability to diolic molecules in the Kerosene phase and exhibits a reduced negative effect on the extraction of boron. Next to decanol, the low viscous 2,6-dimethyl-4-heptanone can be used as solvent modifier. In successive extraction studies, 2-butyl-2-ethyl-1,3-propanediol (BEPD) showed better stability among the diols studied in the presence of decanol in the organic phase. CONCLUSION: Quantitative removal of boron was achieved from industrial waste solutions such as a spent phosphate passivation bath and a cutting fluid, using 0.6 mol L-1 BEPD and 0.6 mol L-1 2,2,4-trimethyl-1,3-pentanediol (TMPD) in 25% decanol/Kerosene organic phase
This work analyses the extraction of Cu(II) using quaternary ammonium and quaternary phosphonium based ionic liquids. Firstly, the chemical suitability of the two ionic liquids was evaluated. They were then tested for extracting copper from solutions (simulated) of liquid mining waste. The effects of the extractant concentration, the sulphate concentration and the stripping solution were studied and the resulting information allowed us to propose a reaction mechanism. Finally, tests were performed using supported liquid membranes (SLM). The results with the synthesised ionic liquids show that [A336/Cy272] is suitable in sulphate, chloride and mixed media, while [C104] is suitable in chloride media. Liquid/liquid extraction tests indicate that it is possible to remove Cu(II) from highly contaminated aqueous solutions (1000 mg/L Cu(II)) using quaternary ammonium type ionic liquids in sulphate, chloride or mixed media, with extraction efficiencies of up to 95%. The best stripping results were obtained in basic and acid media. In contrast, a fouling problem of the membrane was found in supported liquid membrane tests, which occurs after approximately 4 h of testing. (C) 2013 Elsevier B.V. All rights reserved.
Recent restriction of boron concentration in drinking water has produced some problems in the seawater
desalinization plants because the rejection of boron in most of the plants is inadequate. Three ionic liquids
derived from Cyanex 272 as an anion with different cations (from Aliquat 336, Cyphos IL 101 and
Cyphos IL 167) were prepared to be used as boron extractants. Liquid–liquid extraction experiments were
carried out to evaluate the viability of boron separation from high chloride media. The effect of ILs and
boron concentration and pH were determined. Successive extractions, maintaining the organic phase,
provided satisfactory results in order to implement these ILs on supported liquid membrane technologies.
The use of the ionic liquid as a carrier can overcome the inconvenience associated with the membrane
stability. In this sense, the ionic liquids ALiCY and the mixture of Cyphos IL 101 and Cyphos IL
167 with Cyanex 272 have been tested as liquid carrier for boron separation by using a flat sheet supported
liquid membrane. The results obtained allow us to think about the application of this kind of
ILs on the process intensification to remove boron from chloride solutions.
The desalinization of the continental waters is one of the actual challenges on supplying water requirements. Water with high contents in salts is inadequate for drinking water and irrigation uses. In the industry this water involves additional conditioning steps. Salinity in water can determine the aquatic ecosystem and the life of the pants. High concentration of chloride in continental water is a great problem for the exploitation of these natural resources. In general, Cl- in water can be reduced by conventional water treatment processes, like ion exchange or reverse osmosis, but for long scale production these techniques could be very expensive due to resins regeneration or energy costs. This work proposes an alternative solution to chloride reduction from brackish water. The possibility to exchange Cl- to HCO3- anion on a supported liquid membrane using Aliquat 336, Cyphos IL 101 and Cyphos IL 167 as a carriers have been demonstrated. Experimental liquid liquid extraction process has been taken into account to determinate the stability and the easiness of the anion exchange. Alternating HCO3- 1M, and 1000 mg/L of Cl- contacts with the organic phase during fifteen extraction-regeneration cycles, no change in the results have been observed.
Fortuny, A.; Coll, M.T.; Muiños, L.; Kedari, C.S.; Sastre, A. International Conference on Ionic Liquids in Separation and Purification Technology p. P82 Presentation's date: 2011-09-04 Presentation of work at congresses
Coll, M.T.; Fortuny, A.; Sastre, A. 7th European Congress of Chemical Engineering , 19th International Congress of Chemical and Process Engineering p. 445-446 Presentation's date: 2010-08-31 Presentation of work at congresses
This paper describes experimental work and the mathematical modeling of solvent extraction of cadmium(
II) from neutral and acidic aqueous chloride media with a Cyanex 923 extractant in Exxol D-100.
Solvent extraction experiments were carried out to analyze the influence of variations in the composition
of the aqueous and organic phases on the efficiency of cadmium(II) extraction. In neutral and acidic
chloride conditions, the extraction of cadmium(II) by the organophosphorous extractant Cyanex 923 (L)
is based on the solvation mechanism of neutral HnCdCl(2+n) species and the formation of HnCdCl(2+n)Lq
complexes in the organic phase, where n=0, 1, 2 and q = 1, 2. The mathematical model of cadmium(II)
extraction was derived from the mass balances and chemical equilibria involved in the separation system.
The model was computed with the Matlab software. The equilibrium parameters for metal extraction,
i.e. the stability constants of the aqueous Cd–Cl complexes, the formation constants of the acidic Cd–Cl
species and the metal equilibrium extraction constants, were proposed. The optimized constants were
appropriate, as there was good agreement when the model was fitted to the experimental data for each
of the experiments.
Water covers 70% of the Earth’s surface but, even so water is becoming a scarce resource. In
order to achieve the target 7.c of the Millennium Development Goals, to assure potable water
for the people without sustainable access to it, alternative sources must be found.
Considering that the oceans contain 97.5% of the earth’s water, seawater (SW) can be use as a
source of safe drinking water and for irrigation; the salts contained are usually removed by
membrane techniques, especially reverse osmosis (RO). By using this alternative source more
traces of contaminants start to appear in the final product, that is the case of the boron.
The average boron concentration in the seawater is 5 mg/L, if the rejection values for the new
SWRO membranes are between 80-87%, the concentration of boron in the permeate is more
than 0.5 mg/L, exceeding the WHO Guidelines for Drinking-water Quality. To reduce this
limit value is necessary put one additional step of separation.
As well as know, the supported liquid membranes (SLM) are very effective in removing and
recovering metals from liquid effluents at low concentration, since they combine extraction
and stripping processes in one step. For that, this technique must be suitable to extract boron
The main problem of the conventional SLM is the limited time of performance associated to
the stability of the membrane. To avoid it, hollow fiber strip dispersion technique (HFSD) has
been used in this work.
The 1,3 diols, as 2,2,4-trimethyl-1,3-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-ethtyl-
1,3-hexanediol, 2-methyl-2,4-pentanediol, are appropriate to extract boron selectively. The
liquid liquid extraction experimental trials have allowed to choose the 0,3 M BEPD (2-butyl-
2-ethyl-1,3-propanediol) with 20% decanol in kerosene as the best extractant for the boron
separation from neutral or acidic aqueous media. The extraction yield is well and this value
can be maintained after successive extractions, this behaviour is very important for its
application to hollow fiber membrane module by strip dispersion.
The results obtained with flat supported liquid membranes have given permeability
coefficient values witch corroborate the possibility to use this extractant on the hollow fiber
strip dispersion technology.
Goralska, E.; Coll, M.T.; Fortuny, A.; Kedari, C.; Sastre, A.; Bogacki, M. XXI International Symposium on Physisco-Chemical Methods of Separation. ARS SEPARATORIA 2006 p. 92-93 Presentation of work at congresses
Fortuny, A.; Coll, M.T.; Goralska, E.; Kedari, C.; Sastre, A. XXth International Symposium on Physisco-Chemical Methods of the Mixture Separation. ARS SEPARATORIA 2005 p. 125-126 Presentation of work at congresses
Coll, M.T.; Fortuny, A.; Goralska, E.; Kedari, C.; Sastre, A. XXth International Symposium on Physisco-Chemical Methods of the Mixture Separation. ARS SEPARATORIA 2005 p. 122-124 Presentation of work at congresses
Goralska, E.; Coll, M.T.; Fortuny, A.; Kedari, C.; Sastre, A. XXth International Symposium on Physisco-Chemical Methods of the Mixture Separation. ARS SEPARATORIA 2005 p. 130-133 Presentation of work at congresses