Solvent extraction

Claim 2

A reagent composition comprising: (a) one or more hydroxy aryl ketoxime compounds of Formula I (in which R and R', which may be the same or different, each represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; n is 0 or 1; and each of a and b, which may be the same or different, is 0, 1, 2, 3 or 4, the sum of a and b being at least 1; with the proviso that the total number of carbon atoms in R and R' b is from 3,to 25) or Formula II (in which R represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; a is 0, 1, 2, 3 or 4; and Rrepresents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; with the proviso that the total number of carbon atoms in R a and R''' is from 3 to 25); (b) one or more hydroxy aryl aldoxime compounds of Formula III (in which R represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; C is 1, 2, 3 or 4; and the total number of carbon atoms in R is from 3 to 25); (c) a kinetic additive substance in an amount of from 0 to 20 mole percent based on the hydroxy aryl ketoxime present; and, (d) an extraction and stripping equilibrium modifier substance in an amount providing for a degree of modification of the hydroxy aryl aldoxime present of from about 0.66 to about 1.0; the mole ratio of the hydroxy aryl ketoxime present to the hydroxy aryl aldoxime present being from 1:100 to 100:1.

Claim 3

A composition as claimed in claim 1 containing one or more hydroxy aryl ketoximes of Formula I (as defined in claim 1).

Claim 4

A composition as claimed in either of claims 1 and 2 containing one or more hydroxy aryl ketoximes of Formula II (as defined in claim 1).

Claim 5

A composition as claimed in any one of claims 1 to 3 wherein compounds of Formulae I, II or III (as defined in claim 1) satisfy one or more of the following requirements: (a) in a compound of Formula I, a is 1 and b is 0; (b) in a compound of Formula I, n is 0; (c) in a compound of Formula I, n is 1; (d) in a compound of Formula II, a is 1; (e) in a compound of Formula II, Rill represents a methyl group; (f) in a compound of Formula III, c is 1; (g) in one or more of the compounds of Formulae I, II and III, R represents a saturated aliphatic group having 7 to 12 carbon atoms attached to the phenyl group at a position para to the hydroxyl; and (h) in one or more of the compounds of Formulae I, II and III, the groups represented by R comprise a mixture of isomers.

Claim 6

A composition as claimed in any one of claims 1 to 4 comprising at least one hydroxy aryl ketoxime selected from: 2-hydroxy-5-nonyl benzophenone oxime; 2-hydroxy-5-dodecyl benzophenone oxime; 2-hydroxy-5-nonyl phenyl benzyl ketone oxime; and 2-hydroxy-5-nonyl phenyl methyl ketone oxime.

Claim 7

A composition as claimed in any one of claims 1 to 5 comprising at least one hydroxy aryl aldoxime selected from: 2-hydroxy-5-heptyl benzaldoxime; 2-hydroxy-5-octyl benzaldoxime; 2-hydroxy-5-nonyl benzaldoxime; and 2-hydroxy-5-dodecyl benzaldoxime.

Claim 8

A composition as claimed in any one of claims 1 to 6 wherein components (a) and (b) are selected from the following: (i) 2-hydroxy-5-nonyl benzophenone oxime and 2-hydroxy-5-nonyl benzaldoxime; (ii) 2-hydroxy-5-nonyl benzophenone oxime and 2-hydroxy-5-dodecyl benzaldoxime; (iii) 2-hydroxy-5-nonyl phenyl methyl ketone oxime and 2-hydroxy-5-nonyl benzaldoxime; and (iv) 2-hydroxy-5-nonyl phenyl methyl ketone oxime and 2-hydroxy-5-dodecyl benzaldoxime.

Claim 9

A composition as claimed in any one of claims 1 to 7 wherein the mole ratio of the hydroxy aryl ketoxime present to the hydroxy aryl aldoxime present is from 1:4 to 4:1.

Claim 10

A composition as claimed in any one of claims 1 to 8 containing a kinetic additive substance as selected from a-hydroxy-oximes and α,β-dioximes.

Claim 11

A composition as claimed in claim 9 comprising as a kinetic additive substance 5,8-diethyl-7-hydroxy- dodecan-6-oxime or a mixture of 1-(4'-alkylphenyl)-1,2-propane-dione dioximes.

Claim 12

A composition as claimed in any one of claims 1 to 10 wherein a kinetic additive substance is present in an amount of from 0.01 to 5 mole percent based on the hydroxy aryl ketoxime present.

Claim 13

A composition as claimed in any one of claims 1 to 11 containing an extraction and stripping equilibrium modifier substance selected from : C 6 to C 20 aliphatic alcohols; C 6 to C 20 alkylphenols; and organophosphorus compounds.

Claim 14

A composition as claimed in claim 12 containing an extraction and stripping equilibrium modifier substance selected from: n-hexanol; n-octanol; 2-ethyl hexanol; isodecanol; dodecanol; tridecanol; hexadecanol; octadecanol; heptylphenol; octylphenol; nonylphenol; dodecylphenol; tributyl phosphate; and tri(2-ethylhexyl) phosphate.

Claim 15

A composition as claimed in any one of claims 1 to 13 wherein an extraction and stripping equilibrium modifier substance is present in an amount providing for a degree of modification of the hydroxy aryl aldoxime present of from about 0.75 to 0.99.

Claim 16

A process for the recovery of metal values from an aqueous solution comprising: (1) contacting the aqueous solution with an organic phase comprising a water-immiscible solvent and a reagent composition as defined in claim 1 to extract at least a portion of the metal values into the organic phase; (2) separating the resultant metal value pregnant organic phase from the aqueous phase; and (3) recovering metal values from the metal value pregnant organic phase.

Claim 17

A process as claimed in claim 15 wherein the said aqueous solution is a copper containing solution wherefrom copper values are recovered.

Claim 18

The use for the recovery of metal values from aqueous solutions of reagents containing at least one hydroxy aryl ketoxime of Formula I and/or II (as defined in claim 1) and at least one hydroxy aryl aldoxime of Formula III (as defined in claim 1).

Claim 19

A process for the recovery of metal values from an aqueous solution comprising (1) contacting the aqueous solution with an organic phase comprising a water-immiscible solvent and a reagent composition to extract at least a portion of the metal values into the organic phase; (2) separating the resultant metal value pregnant organic phase from the aqueous phase; and (3) recovering metal values from the metal value pregnant organic phase, characterised in that the said reagent composition is a composition comprising: (a) one or more hydroxy aryl ketoxime compounds of Formula I (in which R and R', which may be the same or different, each represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; n is 0 or 1; and each of a and b, which may be the same or different, is 0, 1, 2, 3 or 4, the sum of a and b being at least 1; with the proviso that the total number of carbon atoms in R and R ' b is from 3 to 25) or Formula II (in which R represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; a is 0, 1, 2, 3 or 4; and R''' represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; with the proviso that the total number of carbon atoms in R a and Rill is from 3 to 25); (b) one or more hydroxy aryl aldoxime compounds of Formula III (in which R represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; C is 1, 2, 3 or 4; and the total number of carbon atoms in R c is from 3 to 25); (c) a kinetic additive substance in an amount of from 0 to 20 mole percent based on the hydroxy aryl ketoxime present; and (d) an extraction and stripping equilibrium modifier substance in an amount providing for a degree of modification of the hydroxy aryl aldoxime present of from about 0.66 to about 1.0; the mole ratio of the hydroxy aryl ketoxime present to the hydroxy aryl aldoxime present being from 1:100 to 100:1.

Claim 20

A process for the recovery of metal values from an aqueous solution comprising (1) contacting the aqueous solution with an organic phase comprising a water-immiscible solvent and a reagent composition to extract at least a portion of the metal values into the organic phase; (2) separating the resultant metal value pregnant organic phase from the aqueous phase; and (3) recovering metal values from the metal value pregnant organic phase, characterised in that the said reagent composition is a composition comprising: (a) one or more hydroxy aryl ketoxime compounds of Formula I (in which R and R', which may be the same or different, each represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; n is 0 or 1; and each of a and b, which may be the same or different, is 0, 1, 2, 3 or 4, the sum of a and b being at least 1; with the proviso that the total number of carbon atoms in R and R ' b is from 3 to 25) or Formula II (in which R represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; a is 0, 1, 2, 3 or 4; and R''' represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; with the proviso that the total number of carbon atoms in R a and Rill is from 3 to 25); (b) one or more hydroxy aryl aldoxime compounds of Formula III (in which R represents a saturated aliphatic group having 1-25 carbon atoms, an ethylenically unsaturated aliphatic group having 3-25 carbon atoms or a group of formula -OR" where R" represents a saturated aliphatic group having 1-25 carbon atoms or an ethylenically unsaturated aliphatic group having 3-25 carbon atoms; C is 1, 2, 3 or 4; and the total number of carbon atoms in R c is from 3 to 25); (c) a kinetic additive substance in an amount of from 0 to 20 mole percent based on the hydroxy aryl ketoxime present; and (d) an extraction and stripping equilibrium modifier substance in an amount providing for a degree of modification of the hydroxy aryl aldoxime present of from about 0.66 to about 1.0; the mole ratio of the hydroxy aryl ketoxime present to the hydroxy aryl aldoxime present being from 1:100 to 100:1.

Claim 21

A process as claimed in claim 1 wherein the said reagent composition contains one ore more hydroxy aryl ketoximes of.formula I (as defined in claim 1).

Claim 22

A process as claimed in either of claims 1 and 2 wherein the said reagent composition contains one or more hydroxy aryl ketoximes of Formula II (as defined in claim 1).

Claim 23

A process as claimed in any one of claims 1 to 3 wherein the said reagent composition contains compounds of Formulae III, II and/or I which satisfy one or more of the following requirements (a) in a compound of Formula I, a is 1 and b is 0; (b) in a compound of Formula I, n is O; (c) in a compound of Formula I, n is 1; (d) in a compound of Formula II, a is 1; (e) in a compound of Formula II, R''' represents a methyl group; (f) in a compound of Formula III, c is 1; (g) in one or more of the compounds of Formulae I, II and III, R represents a saturated aliphatic group having 7 to 12 carbon atoms attached to the phenyl ring at a position para to the hydroxyl; and (h) in one or more of the compounds of Formulae I, II and III, the groups represented by R comprise a mixture of isomers.

Claim 24

A process as claimed in any one of claims 1 to 4 wherein the said reagent composition contains at least one hydroxy aryl ketoxime selected from: 2-hydroxy-5-nonyl benzophenone oxime; 2-hydroxy-5-dodecyl benzophenone oxime; 2-hydroxy-5-nonyl phenyl benzyl ketone oxime; and 2-hydroxy-5-nonyl phenyl methyl ketone oxime.

Claim 25

A process as claimed in any one of claims 1 to 5 wherein the said reagent composition contains at least one hydroxy aryl aldoxime selected from: 2-hydroxy-5-heptyl benzaldoxime; 2-hydroxy-5-octyl benzaldoxime; 2-hydroxy-5-nonyl benzaldoxime; and 2-hydroxy-5-dodecyl benzaldoxime.

Claim 26

A process as claimed in any one of claims 1 to 6 wherein the said aqueous solution is a copper containing solution wherefrom copper values are recovered.

Claim 27

A process as claimed in any one of claims 1 to 7 wherein the said water-immiscible organic solvent comprises kerosene.

Claim 28

A process as claimed in any one of claims 1 to 8 wherein the metal values are recovered from the metal value pregnant organic phase by stripping with the use of an acid.

Claim 29

A process as claimed in any one of claims 1 to 9 wherein the said aqueous solution from which metal values are recovered has a pH of from 0.5 to 7.0.