FI56554C - FOERFARANDE FOER SEPARATION AV NICKEL FRAON KOBOLT - Google Patents

Description

-ICfcra ΓβΙ f11itANVERTISEMENT PUBLICATION cccc * tigr- lbj ου utlAggningsskript 55554 C (45) Patent granted il G2 1930 Patent oeddelnt ^ '(51) Kv.lk. * / Lnt.CI. * c 22 B 23 / 04- FINLAND — Fl N LAN D O1) Patent application - PatentansAkning 3711/72 (22) Application chip - Ansöknlngsdag 29 · 12.72 (23) Initial cloud— Glltighetsdag 29 · 12.72 (41) Become public - Bllvit offentllg 01.07 * 73

Patent and Registration Office .... .. , . . , *. (44) Date of publication and month of publication. -

Patent and registration authorities Ansökan utlagd och utl.skrlften publlcerad 31.10.79 (32) (33) (31) Pyydetty etuoikeus — Begird prlorltet 31.12.71

England-England (GB) 60950/71 '(71) Shell Internationale Research Maatschappij NV, Carel van Bylandtlaan 30, The Hague, The Netherlands (NL) (72) Abraham Johannes van der Zeeuw, Amsterdam, Peter Koenders, Amsterdam, Holland-Holland (NL) (7 * 0 Oy Kolster Ah (5 * 0 Method for the separation of nickel from cobalt - Förfarande för separation av nickel frän kobolt

The invention relates to a process for the separation of divalent nickel from trivalent cobalt, which metals are present in the ammoniacal aqueous phase, using liquid-liquid extraction.

A similar separation method is disclosed in U.S. Patent 3,276,863, in which an aliphatic alpha-hydroxyketone oxime such as 5,8-diethyl-7-hydroxy-6-dodecanone oxime is used as the extractant. For the extraction of other valuable metals, e.g. copper, vanadium and molybdenum, NL patent application 661U688 recommends the use of an alkylated 2-hydroxybenzophenone oxime, e.g. 5-dodecyl-2-hydroxybenzophenone oxime. The latter oximes are said to be particularly effective in extracting copper and separating copper from iron in the low pH range, in contrast to the above-mentioned aliphatic alpha-hydroxyketone oximes, which are preferably used at pH higher than 7 * »extraction is significantly enhanced at low pH, 1, U -2.3 when a mixture of these two types of oxime extractants is used. Similar results were obtained when copper was separated according to BE patent 751 80U when the alkylated 2-hydroxybenzophenone oxime contains one or more electron-withdrawing substituents, such as a nitro group, in the aromatic ring.

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It has now surprisingly been found that the above-mentioned alkylated 2-hydroxybenzophenone oximes, and in particular mixtures of such an oxime with aliphatic alpha-hydroxyketone oxime, give excellent results when used as extractants in the separation of Ni (II) Co (II) by liquid-liquid extraction with ammonia. aqueous medium, i.e. in a relatively high pH range. Compared to the results obtained using aliphatic oxime alone, the improvement involves a higher load capacity under similar conditions, with subsequent post-washing of the extracted Ni (II) into dilute sulfuric acid proving to be much more efficient.

The invention relates to a process for the separation of Ni (II) from Co (II), which metals are present in the ammoniacal aqueous phase, by liquid-liquid extraction, by contacting the ammoniacal aqueous phase with an organic phase comprising an organic solvent substantially in water. unmixed, as well as extractable sanate.

The invention is characterized in that (A) 2-hydroxybenzophenone oxime of the formula -

P NOH

. 1. 2. .

wherein R and R independently represent an aliphatic hydrocarbon or hydrocarbonoxy group having 1 to 25 carbon atoms, E is an electron-withdrawing substituent, and each of the subscripts m, n and p may be 0 or 12 1 an integer from 1 to 1 *, provided that R: carbon atoms of n, R and E.

m n P

the total number is 3-25 either alone or together.

(B) with an aliphatic o <-hydroxyketone oxime of the formula R5 -3! The RJ - C - C - R (II) t t '

OH NOH

3 k. .5 ...

wherein R and R represent a hydrocarbon group and R represents a carbon hydrogen group or a hydrogen atom, and / or (C) a 2-hydroxyphenyl aliphatic hydrocarbon ketone oxime of the formula un)

e2 / ^ - (NOH

y 'oh 3 56554 wherein means an aliphatic hydrocarbon having 1 to 25 carbon atoms. ...

or an alkoxy group, E is an electron withdrawing group and each of the subscripts x and y may be 0 or an integer from 1 to 1 + provided that 67.2 ....

The total number of carbon atoms of R, R and E is 3 to 25, or xy alternatively with a mixture of oximes B and C, whereby the nickel enters the organic phase, after which the organic phase thus obtained is separated from the aqueous phase, which mainly contains Co (II): a.

In the above general formula (I), the substituent R 1 may be, for example, an alkyl, aralkyl, alkenyl, alkapolyenyl or alkoxyl group which may be straight-chain or branched and contain inert substituents and / or heteroatoms. The number of carbon atoms of these groups is preferably 5 to 20, and in particular 7 to 1. · Examples of suitable alkyl groups are: methyl, ethyl, tert. butyl, sec. hexyl, sec.octyl, sec.decyl »sec.dodecyl and sec.hexa-Decyl. Suitable alkenyl groups are preferably those without more than one ethylene double bond, such as pentenyl, octenyl, decenyl, dodecenyl and octadecenyl. Most preferred are alkyl groups, especially those having a branched carbon chain, e.g. secondary alkyl. 2. ..... . element. The substituent R may denote, for example, the hydrocarbon groups mentioned above as examples for R1. Provided that the total number of substituents R and / or R present is greater than one (m + n> 1), in a word two such substituents may be the same or different. Most preferred are compounds which do not contain more than one of each of the 2 substituents R and R (m = N = 1), and in particular those which contain only one substituent R1 (m = 1, n * 0), preferably in the 5-position.

If the electron-withdrawing substituents E1 are present in the 2-hydroxyphenyl group, one such substituent should preferably be in its 3 ′ position. However, compounds having no more than one substituent E1 (p = 0 or 1) are preferred. Examples of the electron-withdrawing substituent E 1 are halogens, especially chlorine, bromine and iodine, a nitro group, a cyano group and an alkoxycarbonyl group such as a methoxy or ethoxycarbonyl group, with chlorine being usually preferred. Although the presence of a substituent may be useful in some cases, excellent results are obtained without it (p = 0).

. 1 1.1 The total number of carbon atoms in R, R and E is preferably

m 1 g P

5-20, and in particular 7 "1 ^ · If R and R are each absent (m = n®0), the substituent E1 must, of course, contain the required number of carbon atoms, e.g. in the form of one or more alkoxycarbonyl groups.

k 56554

Examples of useful 2-hydroxybenzophenone oximes of the formula I are: 5-sec-octyl-2-hydroxybenzophenone oxime, 5-sec-nonyl-2-hydroxybenzophenone oxime, 5-sec.dodecyl-2-hydroxybenzophenone oxime, 1-hydroxybenzoxy-2-dodecyloxy sec-pentyl-U'-tert-butyl and 5-sec-octyl-2 *, H ', 5'-trimethyl-2-hydroxybenzophenone oxime. Excellent results have been obtained especially with 5-sec-nonyl-2-hydroxybenzophenone oxime (ij m = 1, η * = ρ = 0). Suitable compounds as defined above and methods for their preparation are set forth in e.g. NL in patent application 661U688 and BE in patent publication 751 80H.

Preferably, a mixture of one or more 2-hydroxybenzophenone oximes of formula I with one or more aliphatic compounds of formula II is used. . ... 3 with its alpha-hydroxyketone oxime. Hydrocarbon groups, R and R are, for example, aliphatic or alkaryl groups, preferably unsaturated hydrocarbon or branched alkyl groups having 6 to 20 carbon atoms.

Examples of suitable groups are: alkenyl groups such as heptenyl, octenyl, decenyl and octadecenyl and, in particular, secondary alkyl groups such as 1-ethylpentyl, 1-ethylhexyl, 1-ethyl-6-methyloctyl, 1-butyldecyl, 1-butylhexadecyl and 1-butyl-11-methyltridecyl.

.... . . 3. 1+ .5

Most preferred are those compounds in which the groups R and R are the same, R being, for example, the hydrocarbon groups mentioned above as examples of 3 U 5 of R and R, but preferably R is a hydrogen atom. Preferably, huli-. 3 U 5, the total number of atoms in R, R and R totals 12-UO, and in particular 12-20. Suitable compounds are, for example, 19-hydroxy-hexatriacona-9,27-dien-18-one oxime 5 56554 and in particular 6,9-diethyl-8-hydroxy-7-tetradodecanone oxime and 5,8-diethyl-7-hydroxy-7-tetradodecanone oxime. hydroxy-6-dodecanone oxime, the latter being particularly preferred. A mixture containing this compound together with 5-seconyl-2-hydroxybenzophenone oxime has given particularly advantageous results when used as an extractant according to the method of the present invention.

The extractant may be a mixture containing at least one of each of components A and C, or more preferably B and C.

In the general formula III of the 2-hydroxylphenyl aliphatic hydrocarbyl ketone oxime (C), the substituent or - if x is greater than 1 - each represents an alkyl, aralkyl, alkenyl, alkapolyenyl or alkoxyl group, the groups being branched or unbranched and may contain inert substituents and / or heteroatoms if desired. The number of carbon atoms of such an R 1 group may be between 1 and 25, preferably between 5 and 20 and especially between 7 and 11 *. Examples of suitable alkyl groups are: methyl, ethyl, tert-butyl, sec-hexyl, sec-heptyl, sec-octyl, 1-> 3,3-tetramethylbutyl, sec-nonyl, sec-undecyl and sec-pentadecyl. Suitable alkenyl groups are preferably those which do not contain more than one ethylene double bond, such as pentenyl, octenyl, decenyl, dodecenyl and octadecenyl. Most preferred are alkyl groups, especially secondary or tertiary alkyl groups. Preferred compounds are those which do not contain more than one substituent R 1 (x = 1), which is preferably located in the 5-position.

. . 7

The aliphatic group R 'may be, for example, an alkyl, alkenyl or alkapolyenyl group. These groups may be either branched or unbranched and may contain inert substituents and / or heteroatoms if desired.

γ

An unbranched group has generally proven to be very advantageous. The number of carbon atoms in the group R may be, for example, between 1 and 20, preferably between 1 and 11. An alkyl group is generally preferred. Examples of suitable alkyl groups are: methyl, ethyl, n-pentyl, n-heptyl, n-octyl, n-nonyl, n-undecyl, n-tridecyl and n-heptadecyl.

6 T

molecule. Preferably, the number of carbon atoms R 0 and R of each substituent is substantially the same.

Optionally, the 2-hydroxyphenyl group has one or more electro-_ -. .2 attracting Substituent E, in which case such substituent should preferably be in its 3-position. However, compounds having no more than 2 single substituents E (y = 0 or 1) are preferred. Examples of the electron-6 66554 and the attracting substituents E are halogen atoms, in particular chlorine, bromine and iodine, a nitro group and an alkoxycarbonyl group such as a methoxy or ethoxycarbonyl group, with chlorine being usually preferred. Although the presence of substituent 2 E may be useful in some cases, excellent results are obtained in its absence (y = 0).

It is to be understood that the total number of carbon atoms in R 1, Re and 2 x E in total should be between 3 and 25, preferably between 10 and 25, while y * in total about 1 IU to about 18 carbon atoms have been found to be particularly suitable. . If R ° Λ is absent (x = 0), the substituents (-ent) E can help to achieve the required number of carbon atoms, if necessary, e.g. in the form of one or more alkoxycarbonyl groups.

Examples of very suitable 2-hydroxyphenyl aliphatic hydrocarbyl ketone oximes (C) are: (5-sec-heptyl-2-hydroxyphenyl) n-heptyl ketone oxime; (5-sec-octyl-2-hydroxyphenyl) -n-oktyyliketonioksiimi; (5-sec-nonyl-2-hydroxyphenyl) n-nonyl ketone oxime; (5-sec-heptyl-2-hydroxy-phenyl) n-nonyl ketone oxime; and (5-sec-octyl-2-hydroxyphenyl) methyl ketone oxime. Other examples are: (5-methyl-2-hydroxyphenyl) -n-tridecyltin oxime; (5-sec-heptyl-2-hydroxyphenyl) methyl ketone oxime; (5-sec-dodecyl-2-hydroxyphenyl) ethyl ketone oxime; (5-sec-undecyl-2-hydroxy-phenyl) n-pentyl ketone oxime; (5-sec-hexyl-2-hydroxyphenyl) n-undecyl ketone oxime; (5-sec-pentadecyl-2-hydroxyphenyl) -n-heptyyliketonioksiimi; (5-sec-octyl-2-hydroxyphenyl) n-undecyl ketone oxime; (5-sec-octyl-2-hydroxyphenyl) n-heptadecyl ketone oxime; and corresponding compounds having a chlorine atom in the 3-position of the phenyl group, such as (5-sec-octyl-3-chloro-2-hydroxy-phenyl) n-nonyl ketone oxime.

When mixtures containing two or more types of extractants are used, their relative amounts can vary within wide limits. Suitable molar ratios between the different types of ingredients can range, for example, from 10: 1 to 1:10. Preferred mixtures containing at least one of the two components A and B generally have suitable molar ratios between A and B of from 10: 1 to 1: U, preferably from 5: 1 to 1: 1 and in particular U : 1 to 2: 1. Similar molar ratios can be used, e.g., for mixtures containing C and B as ingredients.

For the selective extraction of Hi (II) moieties from Co (II) moieties according to the invention, an extractant is used which should be substantially water-insoluble, usually in diluted form in a water-immiscible organic solvent. The concentration of the mixture of extractant or its components can vary widely and is generally in the range of 2 to 50% by weight, preferably 5 to 15% by weight, based on the organic phase. It is recommended that the water-immiscible solvent be selected so that the organic phase is insoluble in the aqueous medium and vice versa or only in a small amount. The intermixability of the phases should preferably not exceed 5 volumes # and in particular should be less than 1 volume - #: ^. Suitable solvents are, for example, halogenated solvents such as chloroform, 1,2-dichloroethane, 1,2-dichloropropane and di (2-chloroethyl) ether, and in particular hydrocarbons, such as fuel oil, toluene and xylenes.

The organic phase may optionally additionally contain other substances, such as an initial preservative, which is generally a long-chain aliphatic alcohol, to prevent the formation of emulsions, which in certain cases may be formed upon extraction of the aqueous medium.

The process of the invention is particularly useful for separating nickel and cobalt fractions from extraction solutions obtained, for example, by extracting suitable ores with ammonia (e.g. under pressure) after the crude ores have been formed into a suitable form, e.g. by crushing, grinding and screening. When the cobalt moieties are involved in a lower degree of oxidation than Co (III), e.g. as Co (II), as is usually the case, they must first be oxidized to a trivalent state, e.g. by exposing the aqueous medium to an oxidant before contacting the organic phase. . The resulting aqueous medium then contains Ni (II) and Co (III) moieties. Suitable oxidants are, for example, hydrogen peroxide or, more preferably, oxygen or an oxygen-containing gas, in particular air.

If the extraction solution is used as a starting material, the oxidation can also be performed during the extraction delivery. The aqueous medium, which is usually a solution, may further contain one or more ammonium compounds, such as carbonate or bicarbonate, sulfate, chloride, nitrate or hydroxide. The concentration of the metal moieties in the aqueous ammonia medium can vary within wide limits and is usually in the range of 0.01 to 1 mol / liter, preferably in the range of 0.05 to 0.5 mol / liter.

The selective extraction of the Ni (II) moieties according to the invention is carried out by contacting the aqueous medium with an organic phase containing the extractant (s), it being advantageous to improve the contact between the phases by vigorous stirring. The Ni (II) moieties then selectively migrate to the organic phase, while the Co (IIl) moieties remain predominantly in the aqueous phase. Stirring is preferably continued until the equilibrium between the phases is 56554, which usually occurs after about 10 seconds 3 minutes. The preferred volume ratio of organic phase to aqueous phase has been found to be between 1: 3 and 3: 1. However, other relationships may be used. In general, the extraction proceeds steadily at ambient temperature. However, higher or lower temperatures are not excluded.

After phase separation, the extracted Ni (II) moieties can preferably be recovered from the loaded organic phase, where they are usually in the form of a solution of a complex with one or more extractant (s), by separating them with an aqueous solution of a strong acid such as nitric or sulfuric acid. being particularly advantageous. The Ni (II) moieties can also be separated from the organic phase by alternating contact with an aqueous acid-containing solution and water. The Ni (II) moieties are thus transferred to the aqueous separation medium as the corresponding nickel salts, e.g. NiSO 4, and can then be recovered therefrom by conventional methods, e.g. salts by evaporation of water and / or crystallization or - preferably - metal by direct electrolysis, while the organic phase, containing the released extractant is preferably reused for further extractions. However, in some cases it is preferable to use a base such as ammonia for the separation process, in which case the nickel moieties are alloyed by evaporation of the ammonia, probably as a hydroxide. It is also possible to recover nickel as a metal directly from the loaded organic phase by hydrogenation of the latter, which often makes it possible to obtain nickel in powder form.

Of course, methods similar to those described above for the recovery of nickel moieties can also be used to recover cobalt moieties from the aqueous raffinate phase. Prior to the recovery of cobalt from this aqueous phase, the latter can be recycled to the extraction unit, e.g. when it is desired to obtain a concentrated solution, and a by-product can be separated from it for the recovery of cobalt.

In carrying out the process of the invention, either the extraction or the separation or both operations can be carried out batchwise in one step or in a series of successive steps, or preferably continuously using, for example, co-current countercurrent methods.

Example I

Extraction experiments were performed in a specially designed separating funnel comprising a graduated, straight-walled vessel with a volume of 0.25 L.

9 56554

There was a stopcock at the bottom for emptying the funnel. The opening at the top was used to accommodate the two-blade mixer grain and also served as a feed opening.

An aqueous ammonia feed solution containing Ni (II) and Co (IIl) was prepared as follows. To the stirred solution obtained by dissolving 1 * 0 g of ammonium carbonate (Brocades) - mainly the double salt of ammonium bicarbonate and ammonium carbamate (ΝΗ ^ ΗΟΟ ^, Η ,, Ν-ΟΟ-ΟΝΗ ^) - in 200 ml of an aqueous solution containing 25% by weight. NH 4, 1.25 g of basic cobalt carbonate (0/00 2, 2 Co (OH) 2, U HgO) containing 0.6 g of Co (II) and 21.00 g of basic nickel carbonate ( NiCO 2, 2 Ni (OH) 2 * 1 * HgO) containing 10.08 g of Ni (II) with the addition of portions in powder form. The resulting solution was then diluted with water to 1 liter and heated for 3 hours at 80 ° C while bubbling air through the solution to oxidize Co (II) to Co (II).

The volume was then made up again to 1 liter.

The extraction solution was prepared by dissolving 0.096 moles of 5-sec-nonyl-2-hydroxybenzophenone oxime and 0.02 U moles of 5,8-diethyl-7-hydroxy-6-dodecanone oxime in fuel oil ("Shellsol K") and diluting to 1 liter.

The aqueous and organic phases were contacted with each other in a phase ratio of 1:10 (v / v) with stirring at the same rotational speed of 2200 rpm. The organic phase immediately turned dark green and the nickel migration was complete in 10 seconds. However, stirring was continued for 3 minutes. The layers were then allowed to separate.

Analysis of the aqueous layer showed that it contained less than 0.1% by weight of # Ni (II) and more than 99% by weight of # Co (II), calculated from the corresponding initial amounts present.

Ni (II) was separated from the organic layer with an equal volume of 2-N HgSO 4 with stirring at the same speed of 2200 rpm. Within 30 seconds, all Ni (ll) had been washed away. Analysis of the aqueous layer after phase separation showed that it contained 100 # Ni (II) originally present in the organic extraction phase and only 0.1% by weight # Co (II) originally present in the aqueous starting solution.

Example II

(a) An aqueous ammonia solution of 0.01 molar for both iii (II) and Co (II) and 0.2 molar for ammonium sulfate was prepared as follows. To a solution obtained by dissolving 2.38 g of NiCl 2 in Et 2 O, 2.38 g of CoCl 2 in H 2 O and 26.3 g of NH 3 in SO 2 in 800 ml of water was added an aqueous solution containing 25 During the addition, Ni (II) and 10 S6 && 4 were formed

A precipitate of hydroxides of Co (H) which dissolves back when more aqueous ammonia is added. When pH 11 was reached, the solution was diluted to 1 liter, after which the pH was readjusted to 11 by dropwise addition of aqueous ammonia. Air was then introduced into the solution for one hour at room temperature to oxidize Co (II) to Co (II).

The extraction solution was the same as used in Example I.

The aqueous and organic phases were then contacted with each other in a 1: 1 (v / v) phase with stirring at 2200 rpm for 3 minutes, after which the layers were allowed to separate. Analysis of the organic phase showed it to contain 0.01 mol / l Ni (II), while no Co (II) was detected.

Ni (II) was then separated from the organic layer with an equal volume of 2-N HgSO 4 with stirring at 2200 rpm, whereby the Ni (II) load was washed away in 30 seconds.

(b) In the same manner as described in (a), the previous extraction was repeated - for comparison only - using a solution containing 32.5 g of 5,8-diethyl-7-hydroxy-6-dodecanone oxime in 1 liter of fuel oil, the solution being 0, 12-raolar for the active substance. Analysis of the loaded organic phase showed that it contained Ni (II) only at a concentration of 0.0062 mol / l.

After separating Ni (II) 2-N H 2 O 2 from the organic phase, the resulting aqueous solution contained only 17.8 wt% of the Ni (II) originally loaded in the organic solution. However, Ni (II) still remaining in the organic phase could be easily separated therefrom in 30 seconds with 2-N HNO 2.

Example II shows that the mixture of two different types of components used in experiment (a) has a significantly better loading capacity with Ni (II) than the extractant used in experiment (b) alone, while separating Ni (II) with dilute H 2 SO 4. it happens much easier. This is important for the recovery of metallic nickel from the resulting solution by electrolysis.

Example III

The aqueous ammonia solution was the same as that extracted in Example II. The extraction solution was a 0.12 molar solution of 5-sec-nonyl-2-hydroxybenzophenone oxime in SHELLSQL KM (registered trademark of a fuel oil fraction).

The aqueous solution and the extraction solution were brought into contact with each other in equal volumes with stirring at the same rotational speed of 2200 rpm. The nickel transition was complete in 10 seconds. However, stirring was continued for another 3 minutes, after which the layers were allowed to separate. Co (II) was not found in the organic layer.

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Nickel with an equal volume of 2-N H 2 SO 4 was then separated from the organic layer by stirring at 2200 rpm. After stirring for U minutes, the resulting aqueous solution contained 73.3% of the nickel originally present in the organic layer. A comparison of the separation result of this example with that of Example II (a) shows that an extractant containing an oxime of type (A) together with an oxime of type (B) and an extractant containing only an oxime of type (A) must have a first extractant. be cheaper.

Claims (6)

A process for separating Ni (II) from Co (III), which metals are present in an ammoniacal aqueous phase, by liquid-liquid extraction by contacting the methionic aqueous phase with an organic phase comprising an organic solvent, which is substantially immiscible with water, and an extractant, characterized in that, as the extractant, (2) a 2-hydroxybenzophenone oxime of the formula ly & l-w '' - Ep 1 1 2 van R and R independently of one another represents Carbon atoms containing aliphatic hydrocarbon or hydrocarbon oxy group, is an electron-containing substituent and each of the sub-indices m, n and p can be 0 or an integer 1-U, subject to the proviso that the total number of carbon atoms in, R 2 and E 2 is 3-25 * mnp either alone or (B) together with an aliphatic hydroxy ketone oxime of the formula R5 λ In II OH NOH • 3 + 5 van R and R represent a hydrocarbon group and R represents a hydrocarbon group or a hydrogen atom, and / or (C) a 2-hydroxyphenyl aliphatic hydrocarbon ketone oxime of the formula ToVi-R7 (ni) E2 represents a 1-25 carbon atoms containing aliphatic hydrocarbon or p alkoxy group, E is an electron attracting group and each of the sub-indices x and y may be 0 or an integer of 1-U under proviso that the total number of carbon atoms in R and E2 is 3-25 or xy