MXPA98007200A - Beta-improved dictones for the extraction of copper from acuo ammoniac solutions - Google Patents

Abstract

The present invention relates to novel and improved modified beta-diketones and to their use in the extraction of copper from aqueous ammoniacal solutions containing copper values, resulting from commercial processes, including, but not limited to, washing. minerals that contain copper, such as sulphide minerals or concentrates resulting from the flotation of these sulfidic minerals. The novel diketones are highly those that have high steric hindrance, such as those represented by the formula IóII. The preferred beta-diketones of the formula (II) are selected from the group consisting of neo-alkyl beta-diketones, such as 1-phenyl-3-neoalkyl-1,3-propanedione in which the neoalkyl group is selected from neohexyl, neoheptyl, neooctyl, neononil or neodeci

Description

BETA-IMPROVED DICTONES FOR THE EXTRACTION OF COPPER FROM AQUEOUS AMMONIUM SOLUTIONS BACKGROUND OF THE INVENTION This application is a continuation request in part of the U.S. No. 08 / 780,759 filed on January 8, 1997 (exponent of attorney K 5832 MIN) the complex description of which is incorporated in the present co-ao reference. FIELD OF THE INVENTION This invention relates to improved, novel beta-dikether's and their use in the extraction of copper from aqueous ammoniacal solutions containing copper values, resulting from commercial processes, including but not limited to leaching of minerals that contain copper, such as the suidic minerals, or concentrates resulting from the flotation of the suidic minerals.

Declaration of: ecnica_ relacior-aaa Practice er. The recovery of copper from sullidic minerals includes the subjection of minerals to the operation of foam to produce the concentrate of the minerals. Valuable aiicüs and to discard the resi uos of notation of ios suliurc =, silicates, aluminates and the like without value. One of these concentrates is a chalcocite concentrate that contains chalcocite and covellite. In U.S. Patent No. 4,022,866 to Kuhn and Arbiter, and in its subsequent document, "Physical and Chemical Separations via the Arbiter Process" 11th International Mining Congress, Article 30; p. 831-847; The leaching of copper sulfide concentrates with ammonia / ammonium sulfate and oxygen is described whereby the sulfate and the dissolved copper can then be recovered by solvent extraction. The reagents for solvent extraction are described in the patent only er-general form as those that preferably separate copper from alkaline solutions. In the document that describes the Arbiter process, the focus is on a complete or almost complete leaching of the concentrate. Another document by Kuhn and Arbiter, "Anaconda's Arbiter Process for Copper," Hydronetallurgy, C1M Bulletin, February 1974, contains a similar description. The U.S. Patent 4,563,156 describes solvent extraction process for the recovery of values c zinc indices from ammoniacal solutions, the shawls can also contain values? E runs, using or using different exage extractive reagents.

The U.S. Patent 2,727,818 describes a method of leaching copper sulfide materials with solutions for ammonia leaching. The extraction with solvents is not described. U.S. Patent Nos. 4,065,502 and 4,175,012 describe beta-diketones which can be used as metal extractants in a liquid-liquid ion exchange process to recover metals such as nickel or copper from aqueous solutions containing metal values, including solutions aqueous ammonia. U.S. Patent No. 4,350,661 describes the extraction of copper from aqueous ammonia solutions by an extraction process first with a beta-diketone followed by a second extraction with an oxime. Otherwise, the use of a mixture of diketone and oxime is described wherein the extractant reagent consists of approximately 5-30 or by volume of the strong reagent (oxime) and 10-60 or by volume of the weak reagent (ceta-diketones). ). In the commonly ceaida application, the American series No. 07/745, C! 3, Australian Patent No. 668358, published on 20 aaost? of 199b, which corresponds to the present, is described ": -a iixiviacic :. partial ae a concentrate of chalcocita, p-_.ru provide a luciu :. of aqueous ammonia leaching with content of copper values, and the use of extraction reagents with little ammonia load, with high copper transfer, such as beta-diketones. An oxime extractant is also described alone or with dicetcna.

DESCRIPTION OF THE INVENTION In this description, except in the operative examples or where explicitly stated otherwise, all numbers describing ingredient quantities or reaction conditions should be understood as modified by the word "approximately". It was found that when contacted with an ammoniacal solution, obtained by leaching a copper sulphide concentrate with ammonia / ammonium sulfate, a preferred diketone extractant reagent, 1-phenyl-3-isophenyl-1,3-propanedione, It will extract the copper, but with repeated use it can be more difficult to exhaust the copper. It is considered that the problem may arise from a synergistic interaction of surfactant-type materials introduced into the organic phase through the leaching liquor, with a ketone that is formed by reaction of ammonia with beta-diketone. Whatever the mechanism, the observation is that the kinetics of the impoverishment of copper becomes slower, so that for a given contact time of the organics loaded with aqueous recovery solution, the organics become less completely impoverished. This presents two disadvantages when the impoverished organics are recycled to the extraction; there is less capacity to extract more copper, and the driving force for copper extraction is reduced, resulting in less complete extraction. Specifically, when a diketone such as l-phenyl-3-isoheptyl-1,3-propanedione is contacted with ammoniacal copper solutions having a relatively high pH, there tends to be a high amount of ammonia coextracted with the copper, for example. -. approximately 5 moles per close relative to the extracted copper. Although this is a relatively small fraction, it constitutes a significant operating cost. If the ammonia is allowed to remain in the organic charge and the extraction continues, the acid will consume the acid and present itself in the recovery solution as the ammonium salt, where it will tend to accumulate over time as the chemical is recycled. recovery solution. It is generally preferred first to wash the love. Zaeo from the organic cor. load putting them in contact CJ :. a solution. dilute aqueous acid. The acid is still corylated in this step, but the ammonium salt was produced in a separate solution of 1.-. recovery solution. The ammonia a = r c? Extraidc represents a cost of the ammonia lost as well as of the acid necessary to remove it from the organic charged. It would be desirable to have a copper extractant from aqueous ammonia that is not only stable and resistant to ketimine formation, but also maintains rapid depletion kinetics and less coextracted ammonia when loaded with copper. It has now been discovered that the use of a sterically hindered beta-ichthone will provide a very efficient and improved process for copper recovery in which a significant improvement in the stability of the extraction kinetics will be achieved. It is considered that the steric hindrance around the functionality of beta-diketone will result in more stability for the conditions of use, reducing to the minimum, if not eliminating the formation of ketimine. It has also been found that the use of diketones having very high steric hindrance will provide another improved process in which the kinetics of extraction will continue to be rapid, and the substantially reduced coextraction of ammonia will occur during the transport of the copper. By "diketone with high steric hindrance", as used herein, it is understood that the diketone has high steric hindrance, whereby carbons bonded to the carbons of carbon-1? The dioerone can together be no more than three hydrogens when: - one of the three carbons is part of a phenyl ring, and not more than two hydrogens, when one of the two carbons is part of a phenyl ring . It is also required that the carbon atom between the two carbonyl carbons carry at least one hydrogen. Particularly preferred diketones are those in which one of the two alpha carbon for the carbonyl carbons is part of an aryl or alkaryl ring, and the other alpha carbon is substituted with three alkyl groups. Although the present invention is particularly useful in applications where ammonia solutions are found for leaching in the treatment of sulfide mineral containing copper, the present invention is applicable or useful in the extraction of copper from any aqueous ammoniacal solution containing copper values. regardless of its origin. Accordingly, in its general application, the present invention is an improvement in the process of extracting and recovering copper from aqueous ammonia solutions in a process consisting of: (1) contacting a mother aqueous ammoniacal solution or impregnating it. copper, containing copper values, with a beta-diketone copper extractant in dissolved water in an organic solvent immiscible in ayua, to extract copper values from the aqueous ammoniacal solution in organic solution forming hereby an organic phase impregnated with copper and an aqueous phase exhausted with copper; (2) separating the aqueous phase and the organic phase; (3) contacting the organic copper impregnation phase with a recovery solution or aqueous acid extraction, whereby the copper indices are extracted from the organic phase to the aqueous acid recovery solution; (4) separating the aqueous acid recovery solution from the organic phase; and (5) recovering the copper from the aqueous acid recovery solution; the improvement in the process of the present invention being the use of a β-diketone extractant with high steric hindrance. In view of which, the present invention also contemplates a new copper extractant consisting of a beta-diketone copper extractant having one aryl or alkaryl group attached to one carbon of the beta-diketone and attached to the other carbon of the beta-diketone. Onyl, a neoalkyl group containing from ca about 16 carbon atoms, cone can be l-phenyl-3- (1-r-eoalkyl, -1,3-propane dione. It is useful in relation to aqueous ammonia solutions from a variety of varieties such as those found in the leaching of chalcocite concentrates.In these applications copper impregnation leaching solutions from which copper will be recovered by extraction will contain in the order of about 15-170 g / 1 of copper and usually about 30-40 g / 1 of copper at a pH of about 8.5 to 11. In solutions from other applications, the solutions can n contain copper at higher levels, in the order of 125-170 g / 1, as can be the solutions found in the solutions? e attack, of the printed boards, jof ammoniacal copper chloride. The improvement in the process consists of using a sterically hindered beta-diketone of the formula I or II. The sterically hindered beta-diketones can be of structure (I): 3 R * where Ri to R; - and R; > to R? sor. equal or different, and they arise from the group consisting of er. hydrogen, an aryl radical, a C-ryl radical containing from ca to approximately carbon atoms, and an alkyl radical containing from 1 to 13 carbon atoms, and R4 is selected from from the group consisting of H and an electron-separating group such as chlorine, nitro and cyano with the conditions : (a) either of two from Ri to R7 can together form a carbocyclic ring, (b) not more three of Ri to R7 can be hydrogen, (c) the entire molecule contains at least 12 carbon atoms, and (d) R $, o and R. taken together consist of a mixture of isomers. In a second embodiment of the invention, the sterically hindered beta-diketones can be of the formula (II): O O R "" II II I R - C - CH - C - C - R - 00 I I R "R" ' The compounds of formula II are modifications of the beta-diketones found in US Pat. Nos. 4,065,502 and 4,175,312. The hindered beta-diketones of the present invention are those wherein R is phenyl or phenyl substituted with alkyl, R 'is alkyl, R "is selected from the group consisting of II and an electron-separating group such as chlorine, nitro and cyano , and R '' 'YR' '' 'sor. same or different and are chosen from the group consisting of II, alkyl having from 1 to about-carbon atoms _. aralkyl having approximately 14 carbon atoms, with the proviso : (a) not more one of R ', R' '' and R "'' 'is H and (b) the total number of carbon atoms. carbons in all groups R is at least 11 and preferably at least 12. Preferred compounds are those in which (i) R is phenyl, R "is H, R 'is propyl or isopropyl, R' '' is ethyl and R "" is methyl; (ii) R is phenyl, R "is H, R 'is a mixture of branched hexyl groups, R'" and R "" are methyl, and. {iii) R is phenyl R "is H, R 'is a straight or branched chain alkyl group containing 3-8 carbon atoms and R' "and R" "are methyl Particularly preferred beta-diketones are those which are prepared from condensation of acetophenone with esters such as methyl neooctanoate, methyl neonanoate and methyl neodecanoate In relation to the diketone, the prefix neo means the next carbon of the carbonyl carbon is completely substituted in the diketone, in this way a neoalkyl group can be illustrate as RI -C-RR in which the R groups, which may be the same or different, are all alkyl groups, consequently, in formula II above, R ', R' '' and R "", which they may be the same or different, all or an alkyl groups containing from 1 to 0 carbon atoms, generally the neoalkyl groups are a mixture of isomers. The neoalkyl group in the beta-diketones of this invention will contain a total of from 6 to about 16 carbon atoms. The total number of carbon atoms in the total beta-diketone molecule will contain at least 15 carbon atoms and can preferably contain up to about 24 carbon atoms. The most preferred diketones of formula II are those where R is phenyl or alkaryl, R "is H and R ', R'" and R "" each are alkyl and the total carbon atoms taken together in R ', R' '' and R '' '' contain from 5 to about 16 carbon atoms, represented by the neoaikyl groups such as neohexyl, neoheptyl, neooctiio, neononil and neodecyl. Especially those diketones are preferred where the total carbon atoms together in R ', R' '' and R "'' 'contain from or to about 10 carbon atoms.

In the nomenclature uses the prefix neo, a neoacid is a carboxylic acid contains a neoaiquilo group. For example, neodecanoic acid, a mixture of isomers available from Exxon, is a 10-carbon carboxylic acid containing a neo-cyclic alkyl group. In the same way, the neooctanoic acid is a carboxylic acid of 5 carbons which contains a group of alkyl neoheptyl. As an example of the mixtures present er. the beta-diketones of inversion, the neoheptyl group is a mixture of isomers in which R 'is propyl or isopropyl, R' '' is ethyl and R '' ' 'is methyl, and wherein R' and R '' 'are ethyl, and R "" is methyl. In the same way, the neononyl group is usually a mixture of isomers in which R "is a mixture of branched hexyl isomers, and R '" and R "" are methyl, and wherein R' is a mixture of straight and branched chain butyl and pentyl groups, R '' 'is a mixture of ethyl and propyl groups, and R "' 'is methyl, wherein the total of R', R '' 'and R' '' 'taken together is 8. The various R groups in the formula I or II are preferably free of substitution and each contains less than about 20 carbon atoms.The preferred diketone which was found particularly suitable in the past is l- phenyl-3-isoheptyl-l, 3-propanedione where the carbon that binds the isoheptyl group to the carbonyl group is not tertiary, However, as noted at the outset, when this diketone under the conditions of use is exposed to high levels of ammonia, and particularly where relatively high temperatures are found, roe deer can be 45 ° Celsius s, the result is the formation of the corresponding ketimine which then results in an emic extraction deficiency in byproducts that can contribute to the very high drag of the lase ac "? --- a in the charged organics. Also, what is the correct amount of c-z.cr-iac? it is extracted with the copper, resulting in additional costs due to the loss of ammonia and the corresponding acid consumption. Surprisingly, beta-diketones of formula II containing the preferred neoalkyl group not only have a much reduced tendency to the formation of ketimine degradation products, but also coextract substantially less ammonia and maintain very rapid kinetics of extraction. , even with prolonged exposure to ammoniacal copper solutions. The beta-diketones containing a neoalkyl group, wherein R ', R' '' and R '' "are all alkyl, are preferred over beta-diketones where?. ' 'is H and one ce R' ', R' '' and R '*' 'is also H, such as l-fer.il-4-ethyl-l, 3-octanedione; The latter compound has improved the resistance to ketimine formation, but coextracts almost the same amount of ammonia as does l-phenyl-3-ischeptyl-1,3-propanedione, and produces substantially slow extraction kinetics after prolonged exposure to the ammoniacal copper solution. The carbon alpha for carbon carbon must be completely substituted with alkyl groups to obtain improvement in all the above properties. In the extraction process, it is possible to use a wide variety of solvents in liquid liquids, which can be used in the recovery process to form the organic phase, in which the diketone extractant is dissolved. These include aliphatic and aromatic hydrocarbons such as erospheres, benzene, toluene, xylene and the like. A choice of essentially water-immiscible hydrocarbon solvents or mixtures thereof will depend on factors, including the design of the solvent extraction plant plant, (mixer-settler units, extractors) and the like. Preferred solvents for use in the present invention are aliphatic or aromatic hydrocarbons having flammability temperatures of 130 degrees Fahrenheit (54.5 ° C) and above, preferably at least 150 degrees, and solubilities in water of less than 0.1% by weight. Solvents are essentially chemically inert. The commercially available representative solvents are the Chevron® ion exchange solvent (available from Standard Oil of California) which has a flammability temperature of 195 degrees Fahrenheit (90.6 ° C); Escaid® 100 and 110 (available from Exxon-Eurepe) having a flammability temperature of 18 ° F, S2.2 C); Norpar > !) 12 (availability of Exxon-USA) with a flammability temperature of I60 ° F (/1.16°C); Conoco® C121- (available at Conoco) with a flammability temperature of 16 ° F ~ 1.16 ° C); and Aromatic 130 (an available aromatic erosion of Exxon-USA, a flammability temperature of I50 ° F (u3. "C)), and other different kerosene and petroleum fractions available from other oil companies, such as the ORFORM series ® SX diluents for solvent extraction (available from Phillips 66: SX 1, 7, 11 and 12 each with a flammability temperature above 150CF (65.6 ° C) varying up to 215 ° F (101 ° C)); the ESCAID® series of hydrocarbon diluents (available from Exxon: 100, 110, 115, 120, 200 and 300, each with a flash point above 150 ° F (65.6 ° C)), and the EXXOC® solvent of 80 (also available to Exxon and having a flammable temperature above 150 ° F (65.6 ° C).) In the extraction process, solutions of organic solvents may contain beta-diketone in an amount approaching 100% solids, but usually the amount will be used in an approximate amount In the process, the volume ratios of the organic phase to the aqueous phase (0: A) will vary widely since contact of any amount of the organic solution of diketone with the aqueous ammonia solution containing Copper will result in the extraction of copper indices in the organic phase. However, for commercial practice the ratios of the organic: acosa phase for extraction are preferably in the range of about 50: 1 to 1:50. Is it desirable to maintain an elective relationship? approximately 1: 1 in the mixing unit by recycling one of the streams. In the extraction step, the organic phase: aqueous extraction medium will preferably be in the range of about 1: 4 to 20: 1. For practical purposes, extraction and purification are normally carried out at ambient temperatures and pressure although lower temperatures and pressures are fully operable. Although the entire operation can be carried out in one operation per batch, the process is more advantageous in a continuous manner with the different streams or solutions recycled for the various operations in the process to recover the copper, including the leaching, extraction and depuration.

In the extraction process the extractant reagent must be soluble in the organic solvent immiscible in water. In general, the diketones of the present invention will be soluble to the extent and amount described above. If it is necessary or desirable to favor the specific desired extraction properties, it is possible to employ solubility modifiers generally known in the art. These modifiers include aliphatic alcohols or long chain esters (6-30 carbons) such as u-hexancl, n-2-ethylhexanol, is? Decanol, isohexadecarol, 1- (1,3,3-trimethylbutyl; -5,7) , -trimethylocyanol and rono- or diisobutyrate of 2, 2, 4-tr imet? l-1, -pentanyl, long-chain phenols with heptyrene, cyclin, noniiienol and dodecylphenol, and organophosphorus compounds such as tri-lower alkyl phosphates (4-8 carbon atoms), especially tributyl phosphate and tri (2-ethylhexyl) phosphate, where it is indicated that it is desirable, it is also possible to employ kinetic additives. avoid the solubility modifiers The present invention also contemplates the use of a catalytic amount of an oxime, in which case the oxime functions as a kinetic additive, in combination with the sterically hindered diketones of the present invention, preferably a hydroxy, aryl-oxy a. By "catalytic amount" as used herein is meant a small amount of oxime in relation to the amount of diketone, preferably from about 0.5 to about 5 moles per cent of oxirallia relative to beta-diketone. These amounts of oxime are particularly effective in accelerating the extraction rate of the copper from the organic phase. The beta-diketones of this invention are also effective co-extractants for copper from ammonia solutions together with strong extractants, as oximes, a similar combination as that described in US Pat. No. 4, 350, as indicated in the foregoing. Er. In this case, the mixture of diketone and? max in the extraction reagent will consist of approximately 5-30., by volume of the strong reagent or? ima and approximately 10-60% by volume of the weaker beta-diketone. Oxime compounds that can be used in catalytic amounts together with the sterically hindered beta-diketones, or can be co-extractants with the beta-diketones are certain oximes such as those described in U.S. Patent No. 4,563,256. The oximes that can be used are those that generally make up the formula: where R1 is a saturated aliphatic group of 1-25 carbon atoms or an ethylenically unsaturated group of 3-25 carbon atoms or OR ", where R ~ is a saturated or ethylenically unsaturated group as defined above, a is a integer of 0, 1, 2, 3 or 4 and R "is H, or a saturated or ethylenically unsaturated group as defined above, with the proviso that ei. total number of carbon atoms in R ~ and R ~ is 3-25, or is phenyl or phenyl substituted with R1 where R is a saturated or cycletically unsaturated group as defined above, qua-. it can be the same or different from R1. The OS say ¡-. U-.no. compue '? rmu 5-he? salicylaldoxime, 5-octyl salicylaldoxime, 5-nonyl, salicylaldoxy a, 5-dodecyl salicylaldoxime, 5-nonyl-2-hydroxyacetophenone oxime, 5-dodecyl-2-hydroxyacetophenone oxime, 5-hydroxy-5-nonylbenzophenone oxime and 2-hydroxy 5-dodecylbenzophenone oxime. Although it may be preferable that a single oxime compound be used in conjunction with beta-diketone, mixtures of oximes may be used to meet the specific requirements of the system. In the purification step, a sulfuric acid solution containing approximately 60-180 g / 1 of sulfuric acid is the preferred scavenger or extractor as this allows the subsequent recovery of the copper by conventional recovery steps in the form of crystals of copper sulphate or by electrolytic extraction for cathode copper. Other mineral acids can be used as hydrochloric and nitric; However, this may require other methods of recovery or handling of specialized equipment. The following example is illustrative of the procedure by which an alkyl or aralkyl substituent can be introduced into Mac.ray beta-diketones, U.S. Patent Nos. 4,065,501 and 4,575,012, such as -phenyl-3-isoheptyl-1, 3-propauodi? Na. A mixture of 55.2 g of anhydrous potassium carbonate, 1. b g of flu? Rurr? of tetrabut-ammoni ?, 24. ü g ae l-phenyl-3-isoheptyl-1,3-propanedione and 150 ml of toluene were subjected to stirring and heating under reflux for 2 hours with a Dean-Stark trap under an atmosphere of nitrogen. The mixture was cooled to room temperature, 7.0 ml of methyl iodide was added and the mixture was heated with stirring at 50 ° C overnight. The product was diluted with toluene and water, and the organic phase was washed with water and extracted under reduced pressure. The residue was distilled in a Kugelrohr apparatus at 100-110 ° C at 0.3 mm Hg to produce 25.6 g of the distillate. The distillate was purified on a column of silica gel and re-distilled in a Kugelrohr apparatus to yield 16.4 g of 1-phenyl-3-isoheptyl-1,3-propanedione. Using the same procedure with benzyl iodide will produce the corresponding 1-phenyl-2-benzyl-3-isoheptyl-l, 3-propanedione. Other hindered beta-diketones can be prepared by the method of Example A of US Pat. No. 4,065,502. Alternatively, a preferred preparation method is the condensation of acetophenone with a suitable methyl ester in an aromatic hydrocarbon solvent using excess sodium hydride as the base. In this manner, methyl neoectanoate is condensed with acetophenone to give if nil-3-neoheptyl-l, 3-propanedione and methyl 2,2-di ethyl octanoate is condensed with acotophenone to give 1- nyl-4, 4- dimethyi, 3-decanedione, in which the product is a mixture of branched chain isomers. It was found that a highly hindered beta-diketone prepared from the condensation of acetophenone with methyl neooctanoate: (a) gives good stability in the presence of ammoniacal copper solutions; (bj maintains its kinetics of depuration or extraction very fast even under aging conditions, and (c) coextracts only a fraction of the amount of ammonia as does 1-phenyl-3-isoheptyl-l, 3-propanedione, a diketone which was employed in the above-described US Pat. No. 4,065,502, while: (d) maintains good extraction concentration By comparison, l-phenyl-4-ethyl-l, 3-propanedione, a compound of formula II in where R "and R" 'are H, gives good stability in the presence of ammoniacal copper solutions, but coextracts almost the same amount of ammonia as l-phenyl-3-isoheptyl-l, 3-prpanedione, and only has moderately faster extraction kinetics This can also be seen through the following experimental data.

Example 1. - AParación ce 1-phenyl-3-r.eoheptil-l, 3-proparodone_i, .-. A 3U0 ml plastic bottom flask with 4 cylinders equipped with mechanical agitation, including nitrogen, thermometer, condenser and funnel for addition was charged with sodium hydride at 60 ° C. mineral oil (20.5 g, 0.51 mol), methyl neo-octanoate (92.3 g, 0.58 mol, prepared from neo-octanoic acid, an Exxon product, and xylene (42.8 g) .The mixture was heated to reflux ( 135 ° C), and then a solution of acetophenone (32.4 g, 0.27 mol) in xylene (19.1 g) was added over 1.25 h.The mixture was refluxed for an additional hour.After cooling to room temperature, the reaction was interrupted by careful addition of methane! (20 ml) and then acidification with 150 g / l sulfuric acid (180 ml). After separation of the layers, the organic phase was washed with water (2 x 100 ml) and brine (100 ml). After drying by passing through anhydrous sodium sulfate, the solution was concentrated in vacuo at 70 ° C at 12 mbar to produce an orange liquid in an impure yield of 63 °. Vacuum distillation, 100 mtorr) through a Vigreux column of 15 cm produced in the middle fraction: 1-phenyl-3-neoheptyl-l, 3-propanodicr.a (X) (37.2 g, 96'-de purity, 0.14 mol; yield 53 '?; boiling point 94-135 ° C). The Dypnona, the product of autcondensation of the acetophenone was not detected in the product. By the substitution of methyl 2-ethyli? Exoate for the methyl neoctane in the above procedure, 1-teni-1-4-ethyl-1, 3-? Cta: -? Dione (Y) was also prepared.

L-phenyl-3-isoheptyl-l, 3-propanedione (Z) from the condensation of acetophenone with methyl isooctanoate was prepared by the method of Example A of US Pat. No. 4,065,502. In (Z) the carbon 4 adjacent to the carbonyl carbon carries two hydrogens and an alkyl group. In (Y), this carbon carries a hydrogen and two alkyl groups. In (X) this carbon does not carry hydrogens and three alkyl groups. According to Exxon, the neooctanoic acid supplier used in the preparation of (X), this material is a mixture of isomers, the most predominant of which contains a methyl, an ethyl and a propyl substituent on the alpha carbon for the carboxylic acid.

Example 2. Copper extraction test An organic phase was prepared by dissolving the beta-diketone in Conoco 170E (a kerosene available from Conoco, Inc.) to produce a 0.95M solution. A volume of the organic phase was stirred for 2 minutes with an aqueous feed solution containing 30 g / 1 Cu, 1.5 g / 1 Zn, 23 g / 1 ammonium sulfate and 56 g / 1 ammonia and the organic phase was filtered and analyzed for the content of runs. A portion of the filtered organic lase was stirred for 2 minutes with a vulumer-equal of a sodium phthalate buffer solution. with a content of 0. ÍM of ac_d .; tituladle; The aqueous alkali was analyzed for the copper content, was titrated for the remaining acidity to allow calculation of the ammonia transferred from the organic phase to the aqueous buffer phase. Finally, a portion of the infiltrated organic phase was stirred for 2 minutes with an equal volume of an aqueous solution containing 3u g / 1 Cu, 30 g / 1 ammonium sulfate and 30 g / 1 ammonia; the organic phase with maximum resulting charge was filtered and analyzed for the copper content. The result for the compounds (X), (Y) and (Z) are given in the following table.

The value for the charge in a contact as a percentage of the maximum load capacity is a measure of the concentration of beta-diketone extraction. The fact that the values in tila C are approximately equal indicates that the increase in this impediment did not weaken the capacity to extract the charged ammonia for the compound (X) is substantially lower than the compounds (Y) or (Z), indicating that the most highly hindered beta-diketone significantly reduces the co-extraction of ammonia with copper.

Example 3. Effect of aging with ammoniacal copper A solution of beta-diketone in Conoco 170E was mixed in a flat bottom flask with an equal volume of an aqueous solution containing 30 g / 1 Cu, 20 g / 1 ammonium sulfate and 44 g / 1 ammonia for 6 days at 45 ° C. The organic phase was then separated and the charged copper was removed by contacting successive portions of aqueous sulfuric acid 150 g / i until the organic phase was light yellow, and then washed twice with water and filtered. A mixture of the filtered organic phase was analyzed by gas chromatography to detect any conversion to ketimine. The amount of ketimine is reported as a percentage of the diketone present; the detection limit is less than C.01 $. - - de ce ce ce ce ce ce ce - -. 'U The data show that the tendency towards ketimine formation is strongly reduced by increasing the steric density.

Example 4. Determination of extraction kinetics A 130 ml portion of the filtered organic phase of Example 3 was charged with copper by stirring two minutes with 115 ml of the aqueous solution containing 30 g / 1 Cu, 1.5 g / 1 Zn, 23 g / 1 of ammonium sulfate and 56 g / 1 of ammonia, and the resulting organic phase was filtered. A sample of the filtered organic phase was analyzed for the copper content. Then, 100 ml of the filtered organic phase was mixed with 100 ml of an aqueous solution containing 35 g / 1 Cu and 150 g / 1 sulfuric acid in a 2 ^ 5 inch square mixing box equipped with a disk impeller Slotted 1H inch diameter rotating at 1780 rpm. The samples of the emulsion were removed at specific time intervals, and the separated organic phase was filtered and analyzed for the copper content. The results are given based on the g / 1 Cu extracted after one minute as a percentage of the g / 1 of Cu extracted after 15 minutes. An additional result for compound Z) is provided in which the extraction kinetics was determined before the aging.

Compound 'extracted (X) 100% - essentially complete in 20 seconds (Y) 88% (Z) 56% (Z) 74% - before aging; the speed depends on the time in which the organic solution with charge remains exposed to co-extracted ammonia. The data show that, with a high degree of steric density, the kinetics of copper extraction is very fast and remains fast even after the aging with ammoniacal copper solution. On the other hand, the less impeded compound (Z) has an extraction speed before aging that is variable, depending on how long the organic solution with charge remains with the co-extracted ammonia, and a speed after aging that is very The compound (Y) having an intermediate degree of steric hindrance provides extraction kinetics that is significantly slower than most compounds with impairment X). These hindered beta-di ketones are then used in ur. process for the recovery and extraction of copper from a solution -which contains ammoniacal copper as described in the pr.-ei ioi on.

Claims (23)

1. CLAIMS 1. In a process for recovering copper from an aqueous ammoniacal solution containing copper indexes, which consists of: (A) contacting a copper-impregnated aqueous ammoniacal solution with a content of copper indexes, with an extractant of water-insoluble beta-diketone copper dissolved in a water-immiscible organic solvent, in order to extract the copper values of the aqueous ammonia solution in the organic solution, thereby forming an organic phase impregnated with copper and an aqueous phase bounded with copper; (B) separating the aqueous phase and the organic phase; 15 (C) contacting the organic copper impregnation phase with an aqueous acid recovery solution; (D) separating the aqueous acid recovery solution which now contains the copper indices of the organic phase; and (E) recovering the copper from the aqueous acidic recovery solution; wherein the improvement consists of the water insoluble beta-diketone extractant which is a beta-diketone with high steric hindrance, wherein the sterically hindered beta-diketone has the formula 1: •. R, OO R7 I II II I Ra - C - C - CH - C - C Re (|) III where Ri to R3 and R5 to R are the same or different, and are selected from the group consisting of hydrogen, a radical aryl, an alkaryl radical containing from 6 to about 18 carbon atoms and an alkyl radical containing from 1 to about 13 carbon atoms, and R 4 is selected from the group consisting of H, chloro, nitrc and cyano with the proviso that: (a, any two of R7 can together form a carbocyclic ring, (b) not more than three of R ^ a RT can be hydrogen, and (c) the total molecule contains at least 12 carbon atoms, and (d) R.R ", R7 taken together consists of a mixture of at least two isomers 2. The process, as defined in claim 1, wherein the sterically hindered beta-diketone has the formula II: O O R "" li II 1 R-C-CH -C - C - R '(H) I I R "R'" where R is lenrlo? íen-. replaced co :. alqai-c, R 'is alkyl, R "is selected from the group consisting of X, chloro, nitro and cyano, and R"' and R '"' are the same or different and are selected from the group consisting of H, alkyl having from 1 to about 8 carbon atoms, and aralkyl having from 7 to about 14 carbon atoms, with the proviso that: not more than one of R ", R" 'and R "' 'are H, and (b) the total number of carbons in all groups R is at least 11, and (c) R ', R' '' and R "" taken together consist of a mixture of at least two isomers. 3. The process as defined in claim 2, wherein R is phenyl, R "is H, R 'is propyl or isopropyl and R '' 'is ethyl, and R "" is methyl. 4. The process as defined in claim 2, wherein R is phenyl, R "is K, R 'is branched hexyl, R'" and R "" are methyl. 5. The process as defined in claim 2, wherein R is phenyl, R "is H, R 'is a mixture of straight and branched chain alkyl groups having from 3 to 8 carbon atoms and R". 'and R' '' 'are methyl. 6. The process as defined in claim 2, wherein the group R R is a neoalkyl group in which R ', R' '' and R "", which may be the same or different, are all alkyl groups containing from 1 to 8 carbon atoms, and the total number of carbon atoms carbon in R ', R' '' and R '' '' is from 5 to approximately 16. 7. The process, as defined in claim 1, wherein the diketone is a mixture of linear branched chain isomers of the phenyl-4,4-dimethyl-l, 3-undecanedione. 8. The process, as defined in claim 1, wherein the diketone is l-phenyl-3-neodecyl-l, 3-propanedione. 9. The process, as defined in claim 1, wherein the diketone is l-phenyl-3-neoheptyl-l, 3-propanedione. 10. The process, as defined in claim 1, wherein the diketone is l-phenyl-3-neohexyl-l, 3-propanedione. 11. The process as defined in claim 1, wherein the diketone is l-phenyl-3-neooctyl-l, 3-propanedione. 12. The process, as defined in claim 1, wherein the diketone is l-phenyl-3-neononyl-1,3-propanedione. 13. The process, as defined in claim 1, wherein the extractant further consists of a hydroxyaryloxime. 14. The process, as defined in claim 13, wherein the hydroxyaryloxime is present in a catalytic amount. 15. The process, as defined in claim 13, wherein the hydroxyaryloxime is a coextractant with the beta-diketone. 16. The process, as defined in claim 13, wherein the hydroxyaryloxime has the formula: where R1 is a saturated aliphatic group of 1 to 25 carbon atoms or an ethylenically unsaturated group of 3-25 carbon atoms or ORJ wherein RJ is a saturated or ethylenically unsaturated group as defined above, a is an integer of G, 1, 2, 3 or 4 and R ~ is H or a saturated or ethylenically unsaturated group as defined above, with the proviso that the total number of carbon atoms in R1 and R "is from 3-25 or is phenyl or phenyl substituted with R1, wherein R is a saturated or ethylenically unsaturated group as defined above, which may be the same as or different from R1.1 The process, as claimed in claim 16, in which e_hydr? xiar -.r? xii -.a is selected from. g up? consisting of o -: - cpt? lsalrc? lald? X? ma, 3-? ct? l oilaidoxima salt, i-no: salrciiald xima, _-dodec? l salrcii alooXii? a, j-ro; u _ -_- hrdr? xiacet? f¿: .uiid o.-_ r..a, 3- 3 - dodecyl-2-hydroxyacetophenone oxime, 5-hydroxy-5-nonylbenzofenone oxime and 2-hydroxy-5-dodecylbenzophenone oxime. 18. A beta-diketone extractant compound adapted to extract copper indices of aqueous, ammoniacal copper-containing solutions, which consist of a beta-diketone compound of formula II: OOR "" 11 11 1 R - C - CH - C - C - R '(H) II R "R'" wherein R is phenyl or substituted phenyl with alkylene, R 'is alkyl, R "is selected from the group H and an electron-separating group which is selected from the group consisting of chlorine, nitro and cyano and R '' 'and R "" are the same or different and are selected from the group consisting of H, alkyl having from 1 to about 8 carbon and aralkyl atoms having from 7 to about 14 carbon atoms, with the proviso that: (a) not more than one of R "," "and R" "are H, (b) ) the total number of carbons in all groups R is at least 11, and (c) R ', R "' and R" '' all together consist of a mixture of at least two i some or. The beta-diketone compound, how it is defined in the claim lo, in d? R.de X eo ienil ?, X '' is X, R 'is propyl or is? Pr? P-ti? And R '' '^ s -.tilo and R' '' 'is meti-le. 20. The beta-diketone compound, as defined in claim 18, wherein R is phenyl, R "is H, R 'is branched hexyl and R'" and R "" are methyl. 21. The beta-diketone compound, as defined in claim 18, wherein R is phenyl, R "is H, R 'is a branched chain alkyl group having from 3 to 8 carbon atoms and R". 'and R' '' 'are methyl. 22. The beta-diketone compound as defined in claim 18, wherein the R group -cR R is a neoalkyl group in which R ', R' '' and R "", which may be the same or different, all are alkyl groups containing from 1 to 8 carbon atoms and the total number of atoms of carbon in R ', R' '' and R '' '' is from 5 to about 16. 23. A mixture of isomers of l-phenyl-4,4-dimethyl-1,3-undecanedione. 24. l-phenyl-3-neoheptyl-I, 3-propanedione 25. 1-phene-5-neohexyl-l, 3-propanedione 2. l-Phenii-3-neoethyl-l, 3-pr? a? di? na 2". 1-phene-5-neononyl-i, 3-pr?