Title of Invention

"A PROCESS FOR THE RECOVERY OF GALLIUM FROM BAYER PROCESS LIQUORS"

Abstract

The invention relates to a process for the recovery of gallium from bayer process liquor.The process steps are: conducting stage I extraction by contacting the Bayer process liquor with an organic phase comprising 10-15 vol% alkylated 8-hydroxy quinoline(kelex 100), 10-15 vol% iso-decanol, 3-7 vol% neodecanoic acid (versatic-10) and 63-77 vol% kerosene at 1.0:1.0 aqueous to organic phase ratio at room temperature, separating the loaded organic and aqueous phases by the known method and scrubbing the said organic and aqueous phases by the known method and scrubbing the said organic phase with 5.0-6.5 M HC1 at 1.0:1.5 organic to aqueous phase ratio and subjected to stripping with 1.0-2.0M HC1 solution at 1.0:1.0 organic to aqueous phase ratio and adding concentrated HC1 to the said strip liquor to raise the required acid concentration to 4M, adding 1.0-5.0g/100ml aliphatic carboxylic acid to the above stripped solution, and conducting the stage II solvent extraction by contacting the stripped solution obtained in step (iii) with an organic phase having a composition of 10-20 vol% tricaprylmethyl-ammonium chloride (aliquant 336), 5-15% iso-decanol and rest kerosene at 1.0:0.25 aqueous to organic phase ratio at room temperature, for about 2 minutes followed by separation of organic phase by known methods, scrubbing the said organic phase with 5.0-6.5M HC1 at 1.0 : 1.0 organic to aqueous phase ratio and stripping with 3.5 - 4.5 M NaOH solution at 1.0 : 0.25 organic to aqueous phase ratio, filtering the solution to remove iron hydroxide and electrowinning the strip solution using copper as cathode and stainless steel as anode in a voltage range from 1.80 to - 2.2V to recover gallium.

Full Text

The present invention relates to a process for the recovery of gallium from bayer process liquors. The bayer process liquor is obtained from alumina industries and contains 450 g/L Na2O, 80g/L AI2O3 and 190±20 ppm of gallium. This invention will be useful in recovering metallic gallium from alumina industries, where gallium is present in the bayer process liquor. Gallium is relatively abundant in nature but is not naturally concentrated. It is usually associated with aluminium in bauxite, nephelines and other ores. It has been also found in the ashes of certain kinds of ore. A major resource for the recovery of gallium is gallium bearing aluminium ores. The spent caustic solution from bayer process, which is recycled, builds up the gallium concentration approximately to 200ppm. Gallium is also obtained from the iron mud or residues that results from the purification of zinc sulphate solutions, in zinc production. The gallium is recovered from bayer process liquors by the process of 1) direct electrolysis, 2) solvent extraction and 3) ion exchange. The ion exchange process is not in the scope of present invention. In the direct electrolysis process the gallium is generally recovered from bayer process liquor by using mercury cathode. The drawbacks of this process are, when the organic content of the bayer process liquor is high, the process becomes uneconomical due to low current efficiency and the use of the mercury is highly toxic to the environment. In such case preliminary separation of gallium with partial enrichment is carried out either by fractional precipitation (by neutralising the alkali with CO2) or by removal of part of alumina by addition of lime and subsequent recovery of gallium by passing CO2 Reference may be made to Bhat and Sundarajan, J.Less Common Metals, 1967, 12 pp: 231-238 wherein they have studied the solvent extraction method for the recovery of gallium from the enriched fraction as mentioned above. In this study about 50% of the alumina content of the liquor was precipitated as calcium aluminate by the addition of lime. The gallia and the remaining part of alumina were then co-precipitated by neutralising the alkali with CO2 This fraction containing about 0.6% Ga2O3 was dissolved in hydrochloric acid and maintaining free acid at 3N. From this solution gallium was extracted by contacting an equal volume of 20% TBP and then recovered by back extraction with water. Gallium was precipitated with ammonia and the gallium hydroxide dissolved in 10% sodium hydroxide, and from which gallium metal was finally obtained by electrolysis using a gallium cathode and nickel anode. The gallium thus obtained was found to be 99% pure with an overall recovery of 90%. The drawbacks are the destruction of the alumina liquor which cannot be recycled back into the bayer process. Reference may be made to Varadhraj el al., J. Appl. Electrochemistry, 1989, 19(1) pp: 61-64, wherein their investigations on the effect of organics employing linear stripping voltammetry techniques on glassy carbon electrodes in alkaline gallate solutions revealed the inhibitive effect of those compounds on the electrodepositions of gallium and hence on gallium recovery from aluminate solutions. Reference may be made to Dorin and Frazer, J Appl. Electrochemistry, 1988, 18(1), pp: 134-141, wherein they have electrodeposited gallium from a synthetic bayer process liquor comprising 4.5M NaOH/0 2M Na2CO3/0.3M NaCl and 1,7M A1(OH)3. The deposition was in part controlled by the mass transfer and in part by electron transfer step. Heavy metal impurities, such as Fe and V, usually found in these liquors, promote the hydrogen evolution reaction, completely inhibiting gallium production if present above certain critical concentrations, i.e. 3 ppm for Fe and 30 ppm for V. The drawbacks of the above mentioned two process are that the direct electrowinning of gallium from bayer process liquor is not possibe if the liquors contain iron and vanadium above their critical limits. Reference may be made to Leveque and Helegorsky, International Solvent Extraction Conference 1977, pp: 439-442, wherein the solvent extraction of gallium from concentrated bayer process liquors using Kelex 100 was first reported. The organic phase was made up of 8.5 vol% of Kelex 100, 10 vol% of n-decanol and 81.5 vol% of kerosene. When this organic phase was contracted with a bayer process liquor containing 75g/L of Al2O3, 194 g/L ofNa2O and 270 ppm of Ga, at 1.0:1.0 aqueous to organic phase ratio at 28°C, 80% of gallium was reported to be extracted in 3h. The drawback of this process is the slow kinetics where the time taken to reach equilibrium was reported to be 3 h. Reference may be made to Pesic and Zhou, J.Metals, 1988, 40 pp:24-26, wherein 80% of gallium extraction was obtained in 4h from synthetic aluminate solutions containing 200 ppm of gallium. The drawback of this process is again slow kinetics. Reference may be made to Borgess and Mason wherein they have studied the solvent extraction of gallium from a weak Brazilian Bayer process liquor containing 110 ppm Ga, 16-25 g/L of Al2O3 and 108-120 g/L of Na2O using 10.0 vol% of Kelex 100, 5.0 vol% of Versatic 10, 8.0 vol% of n-decanol and 77 vol% of kerosene and showed 90% recovery in 2 min. Though the problem associated with the slow kinetics of gallium extraction is overcome by incorporating Versatic 10 acid into the organic phase the process is not addressed the actual recovery of the gallium metal. Reference may be made to Swift, J Am. Chem. Soc, 1924, 46,2375-2381, wherein from 6.0M HCI gallium can be loaded selectively onto diethylether over virtually any probable co-existing elements excepting germanium and Fe (HI). The presence of HCI promotes formation of HGaCU which is extracted by solvation, but above 6.0M HCI competition with acid extraction reduces its recovery. Ether extraction was preceded by removal of heavy metal impurities and Fe (HI) reduction through aluminum. The drawback of this process is its non selectivity to Fe (HI), where aluminium is added to reduce Fe (III)_ to Fe (II). Reference may be made to Mihalov, I and Distin, P.A. Hydrometallurgy, 1992, 28, 13-27, wherien a detailed review on the solvent extraction of gallum from HCI solutions was given where several organic agents such as organophosphorous compounds, D2EHPA, carboxylic acids, ketones, alkyl amines and quarterly ammonium salts are discussed with respect to their extractability of gallium from HCI solutions. Gallium is extracted as GaCl4 into quarterly ammonium salts (eg., Tricapryl mono methyl ammonium chloride - Aliquat 336) by anion exchange. The extraction of gallium is rapid and increases with increasing chloride concentration. The main object of the present invention is to provide a process for the recovery of gallium from Bayer process liquors which obviates the drawbacks as detailed above. Accordingly the present invention provides a process for the recovery of gallium from bayer process liquor which comprises: i) conducting stage I extraction by contacting the Bayer process liquor with an organic phase comprising 10-15 vol% alkylated 8-hydroxy quinoline(kelex 100), 10-15 vol% iso-decanol, 3-7 vol% neodecanoic acid and 63-77 vol% kerosene at 1.0:1.0 aqueous to organic phase ratio at room temperature, ii) separating the loaded organic and aqueous phases by the known method and scrubbing the said organic and aqueous phases by the known method and scrubbing the said organic phase with 5.0-6.5 M HC1 at 1.0:1.5 organic to aqueous phase ratio and subjected to stripping with 1.0-2.0M HC1 solution at 1.0:1.0 organic to aqueous phase ratio and adding concentrated HC1 to the said strip liquor to raise the required acid concentration to 4M, iii) adding 1.0-5 .Og/100ml aliphatic carboxylic acid to the above stripped solution, and conducting the stage II solvent extraction by contacting the stripped solution obtained in step (iii) with an organic phase having a composition of 10-20 vol% tricaprylmethyl-ammonium chloride , 5-15% iso-decanol and rest kerosene at 1.0:0.25 aqueous to organic phase ratio at room temperature, for about 2 minutes followed by separation of organic phase by known methods, iv) scrubbing the said organic phase with 5.0-6.5M HC1 at 1.0 : 1.0 organic to aqueous phase ratio and stripping with 3.5 - 4.5 M NaOH solution at 1.0 : 0.25 organic to aqueous phase ratio, v) filtering the solution to remove iron hydroxide and electrowinning the strip solution using copper as cathode and stainless steel as anode in a voltage range from 1.80 to -2.2V to recover gallium, characterised in that in using an organic phase comprising 10-15 vol % alkylated 8-hydroxy quinoline , 10-15 vol % iso-decanol, 3-7 vol% neodecanoic acid and 63-77 vol % kerosene for stage I extraction and use of aliphatic carboxylic acid in stage II extraction. In an embodiment of the present invention the strip liquor of stage-I extraction may be consisted element composition: Gallium = 365.00-371.00 ppm Aluminium = 250.0-300.00 ppm Vanadium = 9.0-12.0 ppm Iron = 150.0-180.0 ppm Manganese = 1.8-2.5 ppm In an embodiment of the present invention used organic chemicals such as kelex 100, Ascorbic acid, iso-decanol, versatic 10, aliquat 336 & kerosene may be of commercial grade and used inorganic chemicals such as HC1, NaOH may be of analytical grade. In another embodiment of the present invention the aliphatic carboxylic acid used may be such as tartaric acid, citric acid, ascorbic acid. The Bayer process liquor which gets recycled in the Bayer process after alumina precipitation and vanadium sludge precipitation gets enriched in gallium content normally to the extent of 200 ppm. This Bayer process liquor before being sent to bauxite leaching can be subjected to stage-I solvent extraction using organic solvent mixture-1 at 1.0:1.0 aqueous to organic phase ratio for 10 min inorder to extract gallium from the Bayer process liquor. After this step the organic and aqueous phases will be separated and the Bayer process liquor can be sent for bauxite leaching. The gallium loaded organic phase whose composition described above also contains alumina and soda to the extent of 1900 and 1950 ppm, respectively. These impurities are subjected to scrubbing using 5.0-6.5M HCI at 1.0:1.5 organic to aqueous phase ratio by mixing for 3 min. In this step the alumina and soda are removed into the scrub solution, whereas the loaded gallium will remain in the organic phase with an average loss of 1% into the scrub solution. The scrubbed organic phase will then be subjected to stripping step where 99% of the loaded organic phase will be stripped using 1.0-2.0M HCI solution at 1.0:1.5 organic to aqueous phase ratio by mixing for 3 min. The gallium stripped organic phase will be recycled for stage 1 solvent extraction. The gallium loaded strip HCI solution will be brought to the desired HCI concentration by adding concentracted HCI solution, and ascorbic acid will be added at a rate of 1.0-5.0 g/100 ml of strip liquor. Thus prepared strip liquor will be subjected to stage 11 solvent extraction step. The stage II solvent extraction will be conducted at an aqueous to organic phase ratio of 1.0:0.25 by mixing for 2 min. After this step the organic and aqueous phases will be separated and the organic phase will be subjected to scrubbing with 5.0-6.5M HCI at 1.0:1.0 organic to aqueous phase ratio by mixing for 2 min. After this step the organic and the aqueous phases will be separated and the organic phase will be subjected to stripping with 3.0-5.0M NaOH solution at 1.0:1.0 organic to aqueous phase ratio by mixing for 3 min. All the gallium loaded into the organic phase II will be stripped into the caustic solution. After the organic and aqueous phase separation the organic phase will be recycled for further stage II extraction. The iron present in the strip liquor will be precipitated as iron hydroxides and therefore this precipitate will be removed from the aqueous strip liquor by filtration.Thus obtained iron free gallium enriched strip liquor will be subjected to electrolysis using copper cathode and steel anode at a potential of-1.95 to -2.05V. Finally gallium will be deposited on the copper cathode and collected as a metal with > 99% purity. After the deposition the caustic strip liquor will be recycled for further stripping of gallium from the organic phase of stage II solvent extraction. The uptake of gallium by Kelex 100 proceeds through a cation exchange mechanism in which hydroxyl ions are liberated as shown below: Ga(OH)4 + 3HQ(o) - GaQ3(o) + OH + 3 H2O Where HQ is Kelex 100 having chemical name (7-(4-ethyl-l-methyloctyl)-8- hydroxyquinoline) and (o) is indicating organic phase. And the extraction of gallium from HC1 solutions onto Aliquat 336 of chemical name tricaprylmethyl-ammonium chloride is as per the following reaction: GaCL,- + R3R'NCl(o) = R3R'NGaCl4 + Cl-(aq) In the process present invention iron is suppressed from being extracted in the IInd stage extraction using Aliquat 336. The suppression of iron was studied with the additions of aliphatic carboxylic acid such as tartaric, citric and ascorbic acids and out of these ascorbic acid was found to be successful in suppressing iron from being extracted. Approximately 85% of iron can be arrested from being extracted into Aliquat 336 by adding desired amount of ascorbic acid to 50 ml of strip liquor. The remaining 15% iron got precipitated when the loaded Aliquat 336 was contacted with 4.0 M NaOH solution for the purpose of stripping and therefore 100% iron removal from the final strip liquor from which gallium is produced by electrowinning. Novelty of the the present invention is the use of the organic solvent containing Kelex 100, iso-decanol, versatic-10 and kerosene in stage-I extraction which increases the kinetics of the extraction process and also use of aliphatic carboxylic acid such as ascorbic acid in the stage-II extraction reduces the iron impurity in the gallium. The following examples are given by way of illustration of the present invention and therefore should not be construed to limit the scope of the present invention. Solvent extraction (both stage I and stage II) experiments were conducted by preparing the organic phase of the required composition and mixing it thoroughly with the Bayer process liquor in a glass breaker using a mechanical stirrer at 1000 +10 rpm. The glass beaker was immersed in water bath to maintain uniform temperature through out the experiment. All other inorganic chemicals used in this study were of analytical grade and standard laboratory glassware was used for all experimental purposes. EXAMPLE-1 100 ml of Bayers process liquor was stirred with 100 ml of organic solvent-I containing 10 % Kelex 100, 10 % iso-decanol and 5% versatic-10 and 75 % of kerosene for 10 min. and then allowed to settle. The aqueous and organic phases were then separated using separating funnel and a sample was collected from the aqueous solution for gallium analysis. During this stage the organic phase extracts sodium, aluminium and other impurities along with the gallium. Therefore, scrubbing of the organic phase was conducted with 6.0 M HC1 at 1.0:1.5 organic to aqueous phase ratio. During this stage gallium remains in the organic phase, which is then stripped with 1.5M HC1 at 1.0:1.5 organic to aqueous phase ratio. The gallium concentration in the strip liquor was analysed and was found to be 340 ppm, giving 85% recovery into the strip liquor. This strip liquor containing 1.5M HC1 was made up to .4.0M HC1 by adding 14 ml of concentrated HC1 to 100 ml of strip liquor along with 2.0 g /100ml of ascorbic acid for iron suppression. After adding the HC1 solution the concentration of gallium is reduced to 298.0ppm. This was then subjected to solvent extraction stage II for further purification and concentration The organic phase used in stage II was madie up of 15 vol% of Aliquat 336, 10 vol% of iso-decanol and 75 vol% of kerosene. The aqueous to organic phase ratio was maintained at 1.0:0.25 and was mixed thoroughly with the stage I strip liquor for 2 min and then both the phases were separated using separating funnels. The loaded organic phase was scrubbed with 6.0M HC1 at 1.0 :1.0 organic to aqueous phase ratio and subjected to stripping with 4.0M NaOH solution at 1.0:0.25 organic to aqueous phase ratio. Gallium in the final strip liquor was found to be 4.75 g/L .100 ml of this strip solution obtained from the second stage extraction was subjected to electrolysis at -1.8v using EG&G potentiostat /galvanostat model No.273 and gallium was electrowon onto a copper cathode. Stainless steel anode and saturated calomel electrode as reference electrode were used in the electrowinning process. Metallic gallium of about 95% is obtained from the electrolysis of the strip liquor obtained from the Ilnd stage extraction. EXAMPLE - 2 100 ml of Bayers process liquor was stirred with 100 ml of organic solvent I containing 12% Kelex 100, 10% iso-decanol and 10% versatic-10 and 68% of kerosene for 10 min. and then allowed to settle. The aqueous and organic phases were then separated using separating funnel and a sample was collected from the aqueous solution for gallium analysis. During this stage the organic phase extracts sodium, aluminium and other impurities along with the gallium. Therefore, scrubbing of the organic phase was conducted with 6.0 M HC1 at 1.0:1.5 organic to aqueous phase ratio. During this stage gallium remains in the organic phase, which is then stripped with 1.5M HC1 at 1.0:1.5 organic to aqueous phase ratio. The gallium concentration in the strip liquor was analysed and was found to be 345 ppm, giving 86% recovery into the strip liquor. This strip liquor containing 1.5M HC1 was made up to .4.0M HC1 by adding 14 ml of concentrated HC1 to 100 ml of strip liquor along with 2.0 g /100ml of ascorbic acid for iron suppression. After adding the HC1 solution the concentration of gallium is reduced to 300ppm. This was then subjected to solvent extraction stage II for further purification and concentration. The organic phase used in stage II was made up of 12 vol% of Aliquat 336, 10 vol% of iso-decanol and 78 vol% of kerosene. The aqueous to organic phase ratio was maintained at 1.0:0.25 and was mixed thoroughly with the stage I strip liquor for 2 min and then both the phases were separated using separating funnels. The loaded organic phase was scrubbed with 6.0M HC1 at 1.0:1.0 organic to aqueous phase ratio and subjected to stripping with 4.0M NaOH solution at 1.0:0.25 organic to aqueous phase ratio. Gallium in the final strip liquor was found to be 4.5 g/L 100 ml of this strip solution obtained from the second stage extraction was subjected to electrolysis at -2.2v using EG&G potentiostat/galvanostat model No.273 and gallium was electrowon onto a copper cathode. Stainless steel anode and saturated calomel electrode as reference electrode were used in the electrowinning process. Metallic gallium of about 97% purity is obtained from the electrolysis of the strip liquor obtained from the Ilnd stage extraction.. EXAMPLE - 3 100 ml of Bayers process liquor was stirred with 100 ml of organic solvent I containing 12% Kelex 100, 10% iso-decanol and 5% versatic 10 and 73% of kerosene for 10 min. and then allowed to settle. The aqueous and organic phases were then separated using separating runnel and a sample was collected from the aqueous solution for gallium analysis. During this stage the organic phase extracts sodium, aluminium and other impurities along with the gallium. Therefore, scrubbing of the organic phase was conducted with 6.0 M HC1 at 1.0:1.5 organic to aqueous phase ratio. During this stage gallium remains in the organic phase, which is then stripped with 1.5M HC1 at 1.0:1.5 organic to aqueous phase ratio. The gallium concentration in the strip liquor was analysed and was found to be 380 ppm, giving 95% recovery into the strip liquor. This strip liquor containing 1.5M HC1 was made up to 4.0M HC1 by adding 14 ml of concentrated HC1 to 100 ml of strip liquor along with 2.0 g /100ml of ascorbic acid for iron suppression. After adding the HC1 solution the concentration of gallium is reduced to 333 ppm. This was then subjected to solvent extraction stage II for further purification and concentration. The organic phase used in stage II was made up of 15 vol% of Aliquat 336, 10 vol% of iso-decanol and 75 vol% of kerosene. The aqueous to organic phase ratio was maintained at 1.0:0.25 and was mixed thoroughly with the stage I strip liquor for 2 min and then both the phases were separated using separating funnels. The loaded organic phase was scrubbed with 6.0M HC1 at 1.0 :1.0 organic to aqueous phase ratio and subjected to stripping with 4.0M NaOH solution at 1.0:0.25 organic to aqueous phase ratio. Gallium in the final strip liquor was found to be 5.32 g/L .100 ml of this strip solution obtained from the second stage extraction was subjected to electrolysis using EG&G potentiostat/galvanostat model No.273 and gallium was electrowon onto a copper cathode. Stainless steel anode and saturated calomel electrode as reference electrode were used in the electrowinning process. Pure metallic gallium of more than 99% is obtained from the electrolysis of the strip liquor obtained from the Ilnd stage extraction. In a continuous electrowinning plant it is normal practice to maintain a buffer of 40g/L of gallium to run the plant with reasonable current efficiency and therefore the low concentration of gallium which is 5.32 g/L obtained in the final strip liquor will not cause any current efficiency problems during electro winning step. The main advantages of the present invention are 1. The organic phases used in this process can be recycled. 2. Metallic gallium obtained is of high purity 3. The process is environmentally friendly. We Claim: 1. A process for the recovery of gallium from bayer process liquor which comprises: i) conducting stage I extraction by contacting the Bayer process liquor with an organic phase comprising 10-15 vol% alkylated 8-hydroxy quinoline(kelex 100), 10-15 vol% iso-decanol, 3-7 vol% neodecanoic acid (versatic-10) and 63-77 vol% kerosene at 1.0:1.0 aqueous to organic phase ratio at room temperature, ii) separating the loaded organic and aqueous phases by the known method and scrubbing the said organic and aqueous phases by the known method and scrubbing the said organic phase with 5.0-6.5 M MCI at 1.0:1.5 organic to aqueous phase ratio and subjected to stripping with 1.0-2.0M HCI solution at 1.0:1.0 organic to aqueous phase ratio and adding concentrated HCI to the said strip liquor to raise the required acid concentration to 4M, iii) adding 1.0-5.0g/100ml aliphatic carboxylic acid to the above stripped solution, and conducting the stage II solvent extraction by contacting the stripped solution obtained in step (iii) with an organic phase having a composition of 10-20 vol% tricaprylmethyl-ammonium chloride (aliquant 336), 5-15% iso-decanol and rest kerosene at 1.0:0.25 aqueous to organic phase ratio at room temperature, for about 2 minutes followed by separation of organic phase by known methods, iv) scrubbing the said organic phase with 5.0-6.5M HC1 at 1.0 : 1.0 organic to aqueous phase ratio and stripping with 3.5 - 4.3 M NaOH solution at 1.0 : 0.25 organic to aqueous phase ratio, v) filtering the solution to remove iron hydroxide and electrowinning the strip solution using copper as cathode and stainless steel as anode in a voltage range from 1.80 to -2.2V to recover gallium, characterised in that in using an organic phase comprising 10-15 vol % alkylated 8-hydroxy quinoline(kelex 100), 10-15 vol % iso-decanol, 3-7 vol% neodecanoic acid (versatic-10) and 63-77 vol % kerosene for stage I extraction and use of aliphatic carboxylic acid in stage II extraction.. 2. A process as claimed in claim 1 wherein the strip liquor of stage-I extraction consisted element composition Gallium = 365.00-371.00 ppm Aluminium = 250.0 - 300.00 ppm Vanadium = 9.0 -12.0 ppm Iron = 150.0-180.0 ppm Manganese = 1.8-2.5 ppm 3. A process as claimed in claims 1-2 wherein used organic chemicals are alkylated 8- hydroxy quinoline(kelex 100), , Ascorbic acid, iso-decanol, neodecanoic acid (versatic- 10) , tricaprylmethyl-ammonium chloride (aliquant 336) & kerosene are of commercial grade and used inorganic chemicals such as HC1, NaOH are of analytical grade. 4. A process as claimed in claims 1-3 wherein the aliphatic acid is selected from tartaric, citric and ascorbic acid. 5. A process as claimed in claim 1-4 wherein the iron suppression in the strip liquor of stage I solvent extraction is 85%. 6. A process as claimed in climes 1-5 wherein the gallium extraction in stage I extraction is 96% in 10 min stirring the solution of bayer process liquor and organic phase consisting of 12 vol% alkylated 8-hydroxy quinoline(kelex 100), 10 vol% iso-decanol, 5 vol% neodecanoic acid (versatic-10) and 73 vol% kerosene. 7. A process for the recovery of gallium from bayer process liquor substantially as herein described with reference to the examples.

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