FR2669348A1 - Compositions containing hydroxydiphosphonic derivatives for the extraction of metal cations - Google Patents

Abstract

Compositions and a process for the extraction of metal ions present in acidic aqueous solutions. The compositions for the extraction of ions according to the invention, capable of binding metal cations present in acidic aqueous solutions, are characterised in that they contain at least one hydroxydiphosphonic derivative corresponding to formula 1 R-C(OH)(PO3H2)2 (1> in which R denotes a hydrocarbon radical containing at least 16 carbon atoms and at least one ethylenic double bond and/or at least one branch, in solution in an organic solvent. The compositions according to the invention are particularly effective for uranium.

Description

Compositions for extracting metal cations
The present invention relates to compositions and a method for the extraction of metal ions contained in acidic aqueous solutions.

 For many years, we have sought to extract the metal ions contained in industrial wastewater, either to recover valuable metal species, or to purify the waters before discharging them into the natural environment.

 Many techniques use ion exchangers in resin form or in the form of liquid liquid extractant.

 A particular problem is posed by metal ions contained in acidic media, especially by actinides and some rare earths contained in phosphoric acid solutions.

 The problem has been partially solved by the extractive compositions described in European Patent 38764. This patent describes the use of diphosphonic derivatives in liquid-liquid extraction processes. These derivatives are presented as being particularly effective for extracting uranium from solutions of crude phosphoric acid whose P2O5 content can vary from 10 to 50% by weight. These derivatives may especially be hydroxydiphosphonic derivatives corresponding to the formula A- (P03H2) 2 in which A is a hydroxy methyl group bearing an alkyl substituent preferably having at most two branches on the main chain.

 The present inventors have now found new particularly effective compositions for the extraction of metal cations in solution in acidic aqueous solutions.

 The present invention relates to compositions for extracting metal ions, a method of extracting metal ions from an acid solution containing them, and novel hydroxydiphosphonic compounds useful for said compositions.

The compositions for the extraction of ions according to the invention, capable of fixing metal cations contained in acidic aqueous solutions, are characterized in that they contain at least one hydroxydiphosphonic derivative corresponding to formula 1
RC (OH) (P03H2) 2 1 in which R represents a hydrocarbon radical having at least 16 carbon atoms and at least one ethylenic double bond and / or at least one branch, in solution in an organic solvent.

 Among the radicals R having at least one ethylenic double bond, mention may be made of lheptadecenyl-8.

 Among the radicals R having at least one branch, mention may be made of methyl-hexadecyl which gives the hydroxydiphosphonic derivative of isostearic acid, and tetra-methyl-2,6,10,14 pentadecyl which gives the hydroxydiphosphonic derivative of phytanic acid. .

The compositions according to the invention are useful for the extraction of ions from many metals. Among these, there may be mentioned transition metal ions, in particular Ti (IV), V (V),
V (IV), Fe (II), Fe (III), Cu (II), Co (II), Ni (II), Zn (II). It is also possible to mention lanthanides and actinides, in particular
(III), Ce (IV), Th (IV) and U (IV). We can also mention
Ca (II), Al (III), Hg (II) and Pb (II).

 The compositions according to the invention are particularly effective for uranium.

 Hydroxydiphosphonic derivatives 1 have a solubility in organic solvents usually used for liquid-liquid extraction, much higher than most hydroxydiphosphonic derivatives described in the prior art. Contrary to the suggestions of the European Patent 38,764 which has as a preferred variant hydroxydiphosphonic derivatives having at most two branches on the main chain, the studies carried out by the present inventors have shown that the solubility of hydroxydiphosphonic derivatives increases with the degree of branching or For comparison, the solubility of various RC (OH) (PO 3 H 2) 2 derivatives in a 90/10 kerosene-octanol mixture was determined. The solubilities, expressed in moles per liter, are given in Table I below.

TABLE I

<tb><SEP> R <SEP> T <SEP><SEP> Solubility
<tb> C6H5-CH2- <SEP> (comparative) <SEP><0.005
<tb> C6H5-C6H4-CH2- <SEP> (Comparative) <SEP> 0.005
<tb> nC17H35- <SEP> (comparative) <SEP> 0.015
<tb> ethyl-2-hexyl <SEP> 0.3
<tb> methyl-15-hexadecyl <SEP>> 0.5
<tb> heptadecenyl-8 <SEP>> 0.5
<tb> 2,6,10,14 tetramethyl <SEP> pentadecyl <SEP>> 0.5
<Tb>
In addition, compositions according to the invention containing 1 mole of hydroxydiphosphonic derivative per liter were prepared with, as solvent, a 90/10 kerosene / octanol mixture.

The viscosities obtained with the derivatives of isostearic acid and 8-heptadecenylacetic acid are equivalent and greater than that of the phytanic acid derivative.

 It is thus confirmed that the solubility of the hydroxydiphosphonic derivatives 1 increases with the degree of branching of the radical R.

 The hydroxydiphosphonic derivative concentration in the ion exchange composition may vary within a relatively wide range. The lower limit is not really critical. However, the volume of composition required to extract a given amount of ions decreases as the derivative concentration increases.

The upper limit is imposed by the viscosity of the compositions. The particularly high solubility of derivatives 1 leads to very viscous solutions for concentrations close to 0.5 mol / l. Beyond this concentration, the too high viscosity prevents precise test portions and does not allow intimate contact between the aqueous and organic phases during the extraction tests, which leads to extraction results. scattered. The concentration of hydroxydiphosphonic derivative of the compositions according to the invention is advantageously between 0.018 and 0.5 mol / liter.

 The hydroxydiphosphonic derivatives corresponding to formula 1 defined above make it possible to obtain a particularly advantageous family of compositions for extracting metal cations from acidic aqueous solutions.

Indeed, because the derivatives 1 have a high solubility in the organic solvents used for the liquid-liquid extraction and they retain the low solubility in aqueous media inherent in all the hydroxydiphosphonic derivatives, these derivatives have a high degree of solubility. good partition coefficient between an organic phase and an aqueous phase. For example, this partition coefficient is of the order of 104 in the case of an organic phase consisting of an 80/20 keroseneoctanol mixture in contact with a 4 mol / liter aqueous phase of ClO 4.

 Among the solvents conventionally usable for liquid-liquid extraction, there may be mentioned mixtures: kerosene / octonal-1, kerosene / tributylphosphate (TBP), Solv Esso / octanol-1, Solv Esso / TBP, kerosene / Ethyl- 2 hexanol.

 It thus appears that, given the very high solubility of the derivatives of formula 1, the volume of extractive composition, that is to say the volume of organic solvent required to extract a given amount of metal ions from a aqueous solution, is divided by about 20 when using derivatives of formula 1 having a branched or unsaturated radical, instead of an unbranched hydroxydiphosphonic derivative such as the derivative of stearic acid.

 Hydroxydiphosphonic derivatives 1 can be prepared for example by a process as described in patent application WO 84/00966.

 The purity of the hydroxydiphosphonic derivatives obtained was estimated according to several complementary methods.

Mass purity was measured from the neutralization curves. It is possible to obtain, by a modeling method, the percentage of carboxylic acid and phosphorous acid remaining.

The phosphorus composition was obtained by phosphorus determination by plasma emission spectrometry. In this determination, the crude result was decreased by the soluble "phosphorus" which represents the amount of phosphorus passing into the aqueous phase during the first contacts with perchloric acid. This "phosphorus" seems to correspond to residual phosphorous acid (0 to 2%).

The use of the 31P NMR does not make it possible to determine, to the nearest extent, the purity of the synthesized derivatives. However, this method makes it possible to assert the absence of phosphorous acid to within a few percent. In addition, it confirms the presence of the free hydroxydiphosphonic group (with two equivalent phosphorus atoms), by the chemical shift of a singlet, and the environment of the two phosphorus atoms with respect to the carbon chain by the spectrum. obtained according to the NO mode
DECOUPLE which shows in all the cases studied a triplet due to the presence of a CH2 directly attached to the carrier carbon of the hydroxy and the two phosphonic groups.

 The present invention will be described in more detail with reference to the examples below, given by way of illustration but not limitation.

EXAMPLE 1
Preparation of the hydroxylphosphonic derivative of isostearic acid
In a first step, 50 g of isostearic acid (12 moles) was mixed with 54.2 g (8 moles) of PCl 3 and 40.4 g (10 moles) of H 3 PO 3 in 30 ml of sulfolane. After heating at 90 ° C for 9 hours, a crude orange-brown product having the appearance of a soft wax was obtained.

 In a 2nd step, the orange-brown product obtained was mixed with 90 ml of water and 30 ml of concentrated HCl. The mixture was heated at 135 ° C. for 9 hours and then, after cooling, an orange precipitate was obtained which was filtered.

 During a third step, the orange precipitate was solubilized in THF, followed by a second filtration which made it possible to eliminate the polymers giving this orange color to the compound. A white precipitate was then obtained.

 In a fourth step, this precipitate was taken up by a mixture (ether + water).

After drying with a rotavapor, the final product having the following weight composition was obtained

<tb> derivative <SEP> hydroxydiphosphonic acid <SEP> of <SEP> isostearic acid <SEP> 73,8%
<tb> H3PO3 <SEP> 1.6%
<tb> acid <SEP> isostearic <SEP> 3.4%
<tb> water <SEP> 21.2%
<Tb>
Further purification has resulted in a product having the characteristics given in Table II below.

EXAMPLE 2
Preparation of CH3- (CH2) 7-CH = CH (CH2) 7-C (OH) (H2PQ) 2
A mixture of 200 g of oleic acid, 48 g of H 3 PO 3 and 65 g of PCl 3 in 60 ml of sulfolane was heated with stirring under a nitrogen atmosphere at 100 ° C. for 9 hours. 360 ml of H 2 O and 120 ml of conc. HCl were added at room temperature, and the whole heated at reflux (130 ° C.) for 9 hours The product was purified in a manner analogous to that described in US Pat. Example 1

The results of the various analyzes carried out on the product obtained are shown in Table II below.

EXAMPLE 3
Preparation of the hydroxydiphosphonic derivative of phytanic acid
In a first step, 17 g of phytanic acid were mixed with 4.5 g of H 3 PO 3 and 6 g of PCl 3 in 10 ml of sulfolane.

The whole was heated with stirring at 100 ° C. for 9 hours, then 30 ml of H 2 O and 10 mm 3 of concentrated HCl were added at room temperature and the whole was refluxed (130 ° C.) for 9 hours. Then 200 ml of THF was added, filtered and the solvent removed. Finally, the product was purified in a manner analogous to that described in Example 1.

The results of the various analyzes carried out on the product obtained are shown in Table II below. In this table, HDP stands for hydroxydiphosphonic acid.

TABLE II

<tb> Derivatives <SEP> HDP <SEP> of <SEP> | <SEP> Ph <SEP> metrics <SEP> Plasma <SEP> RNN31P <SEP> a <SEP><SEP> in
<tb><SEP> acid <SEP> ppm / P04H3 <SEP>
<tb><SEP> the acid
<tb><SEP> Phytanic <SEP> 78.1% <SEP> 79% <SEP> 20.2
<tb><SEP> Oleic <SEP> 82.8% <SEP> 94.5% <SEP> 20.4
<tb><SEP> Isosteal <SEP> 87.8% <SEP> 97.4% <SEP> 20.3
<Tb>
Examples 4 and 5 illustrate the use of the compositions according to the invention for the extraction of U (IV) ions.

EXAMPLE 4
The solution to be treated was an aqueous solution containing 960 ppm U (IV) and 4 moles HClO4 per liter.

 The extractive composition was a 0.07 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (90/10). 10 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C. for 20 minutes, followed by a resting phase not exceeding 20 minutes.

After treatment, the organic phase contained 9260 ppm of
U (IV), the aqueous phase had a residual U (IV) content of 34 ppm.

EXAMPLE 5
The solution to be treated was an aqueous solution containing 1078 ppm U (IV) and 5 moles H 3 PO 4 per liter.

 The extractive composition was a 0.025 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (90/10). 10 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C. for 20 minutes, followed by a resting phase not exceeding 20 minutes.

After treatment, the organic phase contained 3360 ppm of
U (IV), the aqueous phase had a residual U (IV) content of 742 ppm.

EXAMPLE 6
This example illustrates the harmful influence of the third solvent on the efficiency of the extraction of U (IV) ions.

 A 50 ppm aqueous solutions of U (IV) ions were treated according to the procedure of Example 4 by different extractive compositions containing the hydroxydiphosphonic derivative of isostearic acid, in the octanol-kerosemus mixture. The results are shown in Table III below. It is clear that the extraction efficiency decreases as the octanol content increases. The interest of hydroxydiphosphonic derivatives having high solubility in liquid-liquid extraction solvents is thus confirmed.

TABLE III

<tb><SEP> derivative <SEP> HDP <SEP> Organic phase <SEP> aqueous <SEP> Phase <SEP>
<tb> isostearic <SEP> U (IV) <SEP> ppm <SEP> U (IV) <SEP> ppm
<tb><SEP> 5% <SEP> octanol <SEP> 11.26 <SEP> 400.6
<tb> 95% <SEP> kerosene
<tb> 10% <SEP> octanol <SEP> 24.68 <SEP> 267.4
<tb> 90% <SEP> kerosene
<tb><SEP> 15% <SEP> octanol <SEP> 36.96 <SEP> 143.6
<tb> 85% <SEP> kerosene
<tb> 20% <SEP> octanol <SEP> 48.69 <SEP> 13.1
<tb> 80% <SEP> kerosene
<Tb>
EXAMPLE 7
The solution to be treated was an aqueous solution containing 2000 ppm of Fe (III) and 5 moles of HsPO4 per liter.

 The extractive composition was a 0.05 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (70/30). 2 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring for 25 minutes followed by a resting phase not exceeding 20 minutes. After the treatment, the organic phase contained 1991 ppm Fe (III), the aqueous phase had a residual Fe (III) content of 1004 ppm.

EXAMPLE 8
The solution to be treated was an aqueous solution containing 2000 ppm of Fe (III) and 4 moles of HClO4 per liter.

 The extractive composition was a 0.05 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (70/30). The procedure of Example 7 was carried out.

After the treatment, the organic phase contained 2866 ppm Fe (III), the aqueous phase had a residual content of
Fe (III) of 567 ppm.

EXAMPLE 9
The solution to be treated was an aqueous solution containing 1744 ppm of Fe (II) and 5 moles of H3PO4 per liter.

 The extractive composition was a 0.0247 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (90/10). The procedure of Example 4 was carried out.

After the treatment, the organic phase contained 737 ppm Fe (II), the aqueous phase had a residual content of
Fe (II) of 1590 ppm.

EXAMPLE 10
The solution to be treated was an aqueous solution containing 3000 ppm of Fe (II) and 2 moles of H2SO4 per liter.

 The extractive composition was a 0.05 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (70/30). The procedure of Example 7 was carried out.

After the treatment, the organic phase contained 1392 ppm Fe (II), the aqueous phase had a residual content of
Fe (II) of 2304 ppm.

 The comparison of Examples 7 and 8 concerning Fe (III) and Examples 9 and 10 concerning Fe (II) shows that the kinetics of extraction is lower for the more weakly charged cations. Indeed, during the treatment of a Fe (II) solution with an extractive composition according to the invention, the most concentrated phase of Fe (II) after treatment is the aqueous phase.

 The compositions according to the invention thus make it possible to carry out selective extractions.

EXAMPLES 11 to 15
Aqueous solutions containing 5 moles / liter of H 3 PO 4 and a species to be extracted were treated with a solution of 0.0185 moles of hydroxydiphosphonic acid derivative of isostearic acid per liter of a kerosene / octanol mixture (90/10). 10 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C. for 20 minutes followed by a rest period not exceeding 20 minutes.

Table IV below gives the nature of the ion to be extracted, its initial concentration C (i), its final concentration in the organic phase C (org), and in the aqueous phase.
C (aq). All concentrations are expressed in ppm.

TABLE IV

<tb><SEP> ion <SEP> to
<tb> Example <SEP> | <SEP> extract <SEP> C (i) <SEP> C (org) <SEP> C (aq) <SEP>
<tb><SEP> 11 <SEP> Y (III) <SEP> 2000 <SEP> 630 <SEP> 1937
<tb><SEP> 12 <SEP> The (III) <SEP> 500 <SEP> 880 <SEP> 412
<tb><SEP> 13 <SEP> Th (IV) <SEP> 1200 <SEP> 2400 <SEP> 960
<tb><SEP> 14 <SEP> V (IV) <SEP> 1200 <SEP> 600 <SEP> 1140
<tb><SEP> 15 <SEP> V (V) <SEP> 1200 <SEP> 1450 <SEP> 1055
<Tb>
EXAMPLE 16
The solution to be treated was an aqueous solution containing 1200 ppm of Ce (IV) and 4 moles of HC104 per liter.

 The extractive composition was a 0.0185 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (90/10). 10 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C. for 20 minutes followed by a rest period not exceeding 20 minutes.

After the treatment, the organic phase contained 2550 ppm Ce (IV), the aqueous phase had a residual content of
This (IV) of 945 ppm.

EXAMPLES 17 to 24
Aqueous solutions containing 4 moles of HC104 per liter and a species to be extracted were treated with a solution of 0.02 moles of hydroxydiphosphonic acid derivative of isostearic acid per liter of a kerosene / octanol mixture (90/10). 2 volumes of the aqueous solution were contacted with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C for 20 minutes followed by a rest period not exceeding 20 minutes.

Table V below gives the nature of the ion to be extracted, its initial concentration C (i), its final concentration in the organic phase C (org), and in the aqueous phase.
C (aq). All concentrations are expressed in ppm.

TABLE V

<tb> Examples <SEP> ion <SEP> to <SEP> C (i) <SEP> C (org) <SEP> C (aq)
<tb><SEP> extract
<tb><SEP> 17 <SEP> V (V) <SEP> 51 <SEP> 97.4 <SEP> 2.2
<tb><SEP> 18 <SEP> Ti (IV) <SEP> 48 <SEP> 92 <SEP> 2
<tb><SEP> 19 <SEP> Hg (II) <SEP> 200 <SEQ> 214 <SEP> 94
<tb><SEP> 20 <SEP> Pb (II) <SEP> 207 <SEP> 187 <SEP> 114
<tb><SEP> 21 <SEP> Zn (II) <SEP> 65 <SEP> 6 <SEP> 62
<tb><SEP> 22 <SEP> Cu (II) <SEP> 63 <SEP> 7 <SEP> 60
<tb><SEP> 23 <SEP> Ni (II) <SEP> 59 <SEP> 1 <SEP> 58
<tb><SEP> 24 <SEP> Co (II) <SEP> 59 <SEP> 2 <SEP> 58
<Tb>
These examples illustrate the selective nature of the extraction.

EXAMPLES 25 to 27
Aqueous solutions containing 2 moles of H 2 SO 4 per liter and a species to be extracted were treated with a solution of 0.05 moles of hydroxydiphosphonic acid derivative of isostearic acid per liter of a kerosene / octanol mixture (70/30). 2 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C for 20 minutes followed by a rest period not exceeding 20 minutes.

Table VI below gives the nature of the ion to be extracted, its initial concentration C (i), its final concentration in the organic phase C (org), and in the aqueous phase.
C (aq). All concentrations are expressed in ppm.

TABLE VI

<tb> Examples <SEP> | <SEP> ion <SEP> to <SEP> | <SEP> C (i) <SEP> | <SEP> C (org) <SEP> | <SEP> C (aq)
<tb><SEP> extract
<tb><SEP> 25 <SEP> V (V) <SEP> 3000 <SEP> 4246 <SEP> 880
<tb><SEP> 26 <SEP> V (IV) <SEP> 3000 <SEP> 3088 <SEP> 1456
<tb><SEP> 27 <SEP> Ti (IV) <SEP> 500 <SEP> 1000 <SEP> 0
<Tb>
Examples 25 and 26 confirm that extraction kinetics are lower for weakly charged cations.

EXAMPLE 28
The solution to be treated was an aqueous solution containing 40 ppm of Ca (II) and 0.1 mole of HClO 4 per liter.

 The extractive composition was a 0.02 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (90/10). 2 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C for 20 minutes followed by a rest period not exceeding 20 minutes.

After the treatment, the organic phase contained 71 ppm of Ca (II), the aqueous phase had a residual content of
Ca (II) of 5 ppm.

EXAMPLE 29
The solution to be treated was an aqueous solution containing 27 ppm of A1 (III) and 2 moles of HC104 per liter.

 The extractive composition was a 0.02 mole solution of hydroxydiphosphonic isostearic acid derivative per liter of a kerosene / octanol mixture (90/10). 2 volumes of the aqueous solution were brought into contact with 1 volume of extractive composition under the following conditions: intimate contact with mechanical stirring at 25 ° C for 20 minutes followed by a rest period not exceeding 20 minutes.

After treatment, the organic phase contained 2 ppm of
A1 (III), the aqueous phase had a residual Al (III) content of 26 ppm.

EXAMPLES 30 to 35
Aqueous solutions of H3PO4 containing the U (IV) ion were treated with solutions of 0.005 moles of a hydroxydiphosphonic derivative per liter of a kerosene / octanol mixture.

The procedure of Example 4 was carried out.

Table VII below gives the nature of the hydroxydiphosphonic derivative, the initial concentration C (i) of the ion
U (IV) to extract, its final concentration in the organic phase C (org) and in the aqueous phase C (aq), and the concentration C (H) in H3PO3 of the solution to be treated. The contents of U (IV) are expressed in ppm, the concentration of acid is expressed in moles / l.

TABLE VII

<tb> Example <SEP> Derived <SEP> HDP <SEP> from <SEP> C (i) <SEP> | <SEP> C (org) <SEP> | <SEP> C (aq) <SEP> | <SEP> C (H) <SEP> Kerosene / <SEP>
<tb><SEP> acid <SEP>: <SEP> Octanol
<tb><SEP> 30 <SEP> Phytanic <SEP> 50 <SEP> 200 <SEP> 30 <SEP> 10 <SEP> 90/10
<tb><SEP> 31 <SEP> Oleic <SEP> 50 <SEP> 160 <SEP> 34 <SEP> 10 <SEP> 90/10
<tb><SEP> 32 <SEP> isosteal <SEP> ue <SEP> 50 <SEP> 260 <SEP> 24 <SEP> 10 <SEP> 90/10
<tb><SEP> 33 <SEP> Phytanic <SEP> 400 <SEP> 500 <SEP> 350 <SEP> 5 <SEP> 80/20
<tb><SEP> 34 <SEP> Oleic <SEP> 400 <SEQ> 537 <SEP> 346 <SEP> 5 <SEP> 80/20
<tb><SEP> 35 <SEP> Isostearic <SEP> 400 <SEP> 650 <SEP> 335 <SEP> 5 <SEP> 80/20
<Tb>
All of the preceding examples show that, of the ions which have been the subject of extraction tests, most tend to concentrate in the organic phase.

Some, however, are concentrated in the aqueous phase. By choosing the appropriate compositions, it is therefore possible to carry out selective extractions.

EXAMPLE 36
A green raw industrial phosphoric acid made from a phosphate ore originating in North Carolina (USA) has been processed.

The following table gives the composition of this acid.

<Tb>

P205 <SEP> 357.7 <SEP> g / l <SEP> Cs <SEP> 12 <SEP> mg / l <SEP> l <SEP> The <SEP> 10 <SEP> mg / l <SEP>
<tb> SO4 <SEP> 24.6 <SEP> g / l <SEP> Cl <SEP> 1.4 <SEP> g / l <SEP> l <SEP> Mn <SEP> 43 <SEP> mg / l
<tb><SEP> F <SEP> 12.2 <SEP> g / l <SEP> If <SEP> 2.2 <SEP> g / l <SEP> Ni <SEP> 23 <SEP> mg / l <September>
<tb> Ca <SEP> 0.76 <SEP> g / l <SEP> As <SEP> 6 <SEP> mg / l <SEP> l <SEP> Pb <SEP> 1 <SEP> mg / l
<tb> Mg <SEP> 4.01 <SEP> g / l <SEP> Cd <SEP> 25 <SEP> mg / l <SEP> Ti <SEP> 357 <SEP> mg / l
<tb> Fe <SEP> 5.7 <SEP> g / l <SEP> Co <SEP> 1.5 <SEP> mg / l <SEP> U <SEP> 68.5 <SEP> mg / l
<tb> Al <SEP> 2.33 <SEP> g / l <SEP> Cr <SEP> 0.5 <SEP> mg / l <SEP> V <SEP> 30 <SEP> mg / l
<tb> Na <SEP> 0.57 <SEP> g / l <SEP> Cu <SEP> 1.5 <SEP> mg / l <SEP> Y <SEP> 50 <SEP> mg / l
<tb><SEP> K <SEP> 0.42 <SEP> g / l <SEP> Eu <SEP> 1 <SEP> mg / l <SEP> Zn <SEP> 335 <SEP> mg / l
<tb><SEP> C (org) <SEP> 0.1 <SEP> g / l
<Tb>
The aqueous solution to be treated has previously been reduced by Fe (O) to oxidation state 0, in the form of filings or powder, for example. Subsequently, seven successive contacts were made at 20 ° C. for 20 minutes followed by a rest not exceeding 20 minutes with an extractive solution containing 0.02 moles of hydroxydiphosphonic acid derivative of isostearic acid per liter of a kerosene mixture. octanol (90/10) 10 volumes of the aqueous solution were contacted with 1 volume of extractive composition.

After the second contact all the uranium was extracted (it remained less than 5% after the first contact). Once the uranium has been extracted, lanthanum, yttrium, then titanium and, finally, iron have been extracted first.
After 7 contacts, 100% of the uranium, 61% of the lanthanum, 24% of the yttrium, 22% of the titanium and 1.5% of the iron were extracted.

 The examples given above, although carried out under non-optimized conditions, nevertheless show the high efficiency of the extractive compositions of the invention.

Claims (14)

 1. Compositions for extracting metal ions contained in acidic aqueous solutions, characterized in that they comprise, in solution in an organic solvent, at least one hydroxydiphosphonic derivative corresponding to the formula  Wherein R represents a hydrocarbon radical having at least 16 carbon atoms and at least one ethylenic unsaturation and / or branching.  2. Compositions according to claim 1, characterized in that the R radical represents a heptadecene-8 radical.  3. Compositions according to claim 1, characterized in that the R radical is a methyl-15 hexadecyl radical.  4. Compositions according to claim 1, characterized in that the R radical is a tetramethyl-2,6,10,14 pentadecyl radical.  5. Compositions according to any one of claims 1 to 4, characterized in that the hydroxydiphosphonic derivative concentration is between 0.018 and 0.5 mol / liter.  6. Process for extracting metal ions contained in an acidic aqueous solution, characterized in that it consists in bringing said acidic aqueous solution into contact with a composition according to any one of Claims 1 to 5.  7. Process according to claim 6, characterized in that it is used for the extraction of transition metal ions.  8. Process according to claim 6, characterized in that it is used for lanthanide or actinide ions.  9. The method of claim 8, characterized in that the ions to be extracted are U (IV), Th (IV), La (III), Ce (IV).  10. Process according to claim 6, characterized in that it is used for the extraction of Ca (II), Al (III), Hg (II) or Pb (II).  11. hydroxydiphosphonic derivative having the formula R-C (OH) (PO3H2) 2 wherein R represents a hydrocarbon radical having at least 16 carbon atoms and at least one ethylenic unsaturation and / or branching.  12. Derivative according to claim 11, characterized in that R represents

 13. Derivative according to claim 11, characterized in that R represents

 14. Derivative according to claim 11, characterized in that R represents CH3- (CH2) 7-C = C- (CH2) 7-