CN-121518839-B - Comprehensive recycling method of scandium, nickel, cobalt and manganese

CN121518839BCN 121518839 BCN121518839 BCN 121518839BCN-121518839-B

Abstract

The invention discloses a comprehensive recycling method of scandium, nickel, cobalt and manganese, and belongs to the technical field of metal production or refining. The method comprises the steps of adding sulfuric acid to leach cobalt nickel hydroxide, introducing oxygen or air to oxidize ferrous ions to obtain oxidation leaching solution, carrying out vanadium precipitation and iron removal on the oxidation leaching solution, separating to obtain scandium-containing iron vanadium slag and second leaching solution, introducing SO 2 and oxygen/air into the second leaching solution to oxidize divalent manganese, separating to obtain manganese oxide slag and third leaching solution, forming a composite extractant from an organic phosphoric acid extractant and an organic carboxylic acid extractant, carrying out nickel-cobalt extraction on the third leaching solution after saponification of the composite extractant, carrying out activation roasting on the scandium-containing iron vanadium slag by using concentrated sulfuric acid, carrying out scandium extraction on the fourth leaching solution by using the composite extractant, and separating and recycling scandium to realize separation from iron. The invention can realize comprehensive recovery of scandium, manganese and nickel cobalt, and can realize high-efficiency extraction of nickel cobalt and effective separation of nickel cobalt from other metals.

Inventors

WANG WEIWEI
LIU CHENG
QIN BO
LV DONG
XU YUEHE
WANG KUITING
LIU GUO

Assignees

中国恩菲工程技术有限公司
中国有色工程有限公司

Dates

Publication Date: 20260508
Application Date: 20260115

Claims (10)

1. The comprehensive scandium-nickel-cobalt-manganese recovery method is characterized by comprising the following steps of: step S1, adding a dilute sulfuric acid solution into cobalt nickel hydroxide for leaching, and carrying out solid-liquid separation to obtain a first leaching solution; s2, adjusting the pH value of the first leaching solution to be 1.0-4.5, introducing oxygen or air into the first leaching solution, and oxidizing ferrous iron at the reaction temperature of 20-45 ℃ to obtain oxidized leaching solution; S3, adding a alum precipitation reagent into the oxidation leaching solution, carrying out alum precipitation and iron removal by using an iron alum ore method, and carrying out solid-liquid separation to obtain scandium-containing iron alum slag and a second leaching solution; s4, regulating the pH value of the second leaching solution to be 3.0-6.5, introducing SO 2 and oxygen/air into the second leaching solution, and carrying out divalent manganese oxidation at the oxidation reaction temperature of 45-95 ℃ and carrying out solid-liquid separation to obtain manganese oxide slag and a third leaching solution, wherein the volume fraction ratio of the introduced SO 2 to the oxygen is (3-20): 100; S5, forming a composite extractant by adopting an organic phosphoric acid extractant and an organic carboxylic acid extractant; S6, saponifying the composite extractant, and performing nickel-cobalt extraction on the third leaching solution by adopting the saponified composite extractant so as to obtain a nickel-cobalt product through separation and purification; Step S7, mixing concentrated sulfuric acid with the scandium-containing iron vitriol slag for activation roasting to obtain activated scandium-containing iron vitriol slag, adding a dilute sulfuric acid solution into the activated scandium-containing iron vitriol slag for leaching, and filtering to obtain a fourth leaching solution; and S8, scandium extraction is carried out on the fourth leaching solution by adopting the composite extractant, and scandium extraction loaded organic phase and iron-containing raffinate are obtained.
2. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S1, the pH value of a leaching system is 1.0-6.5, and the leaching temperature is 15-45 ℃; and/or the concentration of the dilute sulfuric acid solution is 0.1-3 mol/L, the liquid-solid ratio of the leaching system is 5:1-2:1, and the leaching time is 5-50min.
3. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S2, the oxidation reaction time is 2-20min; And/or, in the step S2, before introducing oxygen or air, adding a reagent containing cupric ions as a catalyst for iron oxidation, wherein the concentration of cupric ions in the reagent containing cupric ions is 0.005-0.05mol/L.
4. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, Step S3, before adding the alum precipitation reagent, regulating the pH value of the oxidation leaching solution to be 0.5-3.0, wherein the reaction temperature is 40-95 ℃ and the reaction time is 40-400min when the alum precipitation is carried out for iron removal; And/or, in the step S3, after adding the alum precipitating reagent, controlling the molar ratio of the total amount of ammonia, sodium and potassium to the total amount of iron scandium metal in a reaction system to be 1 (1.1-5.5): 1, wherein the alum precipitating reagent is a solution containing one or more sulfates of ammonia, sodium and potassium.
5. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S4, the oxidation reaction time is 5-30min, and/or, before introducing SO 2 and oxygen/air, the method further comprises the step of adding a ferric ion-containing reagent, wherein the concentration of ferric ions in the ferric ion-containing reagent is 0.001-0.1mol/L.
6. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S5 of the process, More than one of the organic phosphoric acid extractant P204, P507 and Cyanex 272; the organic carboxylic acid extractant is more than one of naphthenic acid, heterogeneous acid Versatic 10 and heterogeneous acid Versatic 911; the mass ratio of the organic phosphoric acid extractant to the organic carboxylic acid extractant is (0.1-10) 1; The volume concentration of the extractant in the composite extractant is 5-50%, and the diluent is one or more selected from 5# solvent oil, 260# solvent oil and sulfonated kerosene.
7. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S6, the extraction stage number is 3-6, the extraction temperature is 20-60 ℃ at each stage, the extraction time is 3-6min at each stage, the ratio of the saponification extraction organic phase to the aqueous phase is (0.1-10): 1, and the equilibrium pH of the extraction reaction extraction aqueous phase is 4.0-6.5; and/or, in the step S6, after the nickel cobalt is extracted, the method further comprises the steps of adopting dilute sulfuric acid washing liquid to wash the extracted loaded organic phase, carrying out back extraction on the washed extracted loaded organic phase to obtain a nickel cobalt product, The washing level is 2-5, and the concentration of the dilute sulfuric acid washing liquid is 0.01-0.5 mol/L; the back extraction stage number is 3-8, sulfuric acid back extraction liquid is adopted during back extraction, and the concentration is 0.5-5 mol/L.
8. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S7, the temperature of the activation roasting is 180-300 ℃, and the mass ratio of the concentrated sulfuric acid to scandium-containing iron alum slag is (0.1-0.45): 1; And/or in the step S7, the liquid-solid ratio of the activated scandium-containing ferric alum slag to the dilute sulfuric acid solution is 1 (2-8), the concentration of the dilute sulfuric acid solution is 2-15%, and the leaching temperature is 40-90 ℃.
9. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S8, scandium extraction is carried out at 3-10 stages and at 20-60 ℃ for 2-5min, and the equilibrium pH of the extracted water phase reaction is 0.5-2.5; and/or in the step S8, the scandium is extracted, and then the scandium is subjected to precipitation back extraction by adopting a precipitation back extraction agent to obtain scandium precipitate, and the scandium precipitate is calcined to obtain a scandium oxide product, wherein the precipitation back extraction agent is one or more of oxalic acid, ammonium oxalate, citric acid and ammonium citrate, the back extraction stage number is 3-6, and the calcining temperature is 600-900 ℃ for 2-4 hours.
10. The comprehensive recycling method of scandium, nickel, cobalt and manganese according to claim 1, which is characterized in that, In the step S1-step S4, an alkaline neutralizer or sulfuric acid is adopted to adjust the pH value of each reaction system, wherein the alkaline neutralizer is one or more of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and ammonium carbonate; in the step S6, the saponification agent adopted in the saponification is one or more of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and ammonium carbonate, the saponification rate is 10-60%, and the saponification waste liquid generated in the saponification is recycled to the step S3 as a alum precipitating reagent.

Description

Comprehensive recycling method of scandium, nickel, cobalt and manganese Technical Field The invention relates to the technical field of metal production or refining, in particular to a comprehensive recycling method of scandium, nickel, cobalt and manganese. Background Laterite nickel ore has become the main nickel cobalt resource ore with associated scandium resources. The laterite-nickel ore wet smelting process comprises the procedures of acid leaching, impurity removal, nickel cobalt precipitation and the like. Cobalt nickel hydroxide precipitation is a relatively popular intermediate product obtained by hydrometallurgical laterite nickel ores. The purpose of the cobalt nickel hydroxide refining process is to remove impurities from the system to obtain nickel cobalt metal or compounds thereof. The nickel cobalt hydroxide contains iron and manganese besides nickel cobalt, and enters acid leaching liquid along with nickel cobalt in the acid leaching reaction process of the nickel cobalt hydroxide, and iron is removed in the refining separation process to obtain a pure nickel cobalt product. Iron ions are main impurities in the separation and utilization of valuable metals, and iron alum method iron removal is a common iron removal method. Iron ions in the cobalt nickel hydroxide leaching solution are divalent and trivalent. The conventional iron vitriol method has the problems that the ferrous iron oxidation pH is far higher than the vitriol precipitation pH, and the available oxidant in the pH range suitable for vitriol precipitation has the defects of low oxidation rate, high cost and the like. Manganese is one of the impurities leached with nickel and cobalt and treated in the subsequent separation process, and it has an interfering effect on the extraction of nickel and cobalt, affecting the purity of the product. The cobalt nickel hydroxide prepared from a great deal of laterite-nickel ore contains scandium, which is a harmful impurity for nickel-cobalt smelting and is a rare earth resource. The inventor notices that the technology for recovering scandium by adopting scandium precipitation method has the problems of low precipitation rate and difficult precipitation due to lower concentration of scandium in the system, and the technology for extracting and separating scandium by adopting acidic organophosphorus extractants P204, P507 and the like has the problems of difficult phase separation and low yield due to the need of back extraction by adopting high-concentration alkali solution. The existing nickel cobalt extraction is carried out in the extraction and separation of acidic organophosphorus extractants P204, P507, cyanex272 and the like (P204 extraction is carried out, P507 extraction is carried out, cobalt is carried out, and Cyanex272 deep extraction is carried out), but the inventor notices that the process needs to carry out extraction at a higher pH value, a large amount of neutralization alkali is needed, a large amount of salt-containing acid-containing waste liquid generated in the saponification process of the extractant cannot be utilized, and in order to solve the problem that ions such as iron, aluminum, manganese, calcium, magnesium and the like are easy to interfere with the extraction of nickel cobalt, the iron, aluminum, manganese and the like need to be removed by precipitation and other methods before the extraction, a large amount of neutralization alkali is consumed, and the generated salt solution cannot be utilized. Because iron ions in the solution are Fe 3+ and Fe 2+, in the method of the Chinese application CN103468948A, scandium and iron aluminum are coprecipitated by adjusting the pH value to 3.0 or above when iron and aluminum are further removed, and then the scandium and the iron aluminum are precipitated in a hydroxide form, so that scandium in the nickel-cobalt solution is removed and recovered. However, the inventor finds that in practice, when hydroxide coprecipitation is formed, the reaction end point is difficult to judge due to the special property that aluminum hydroxide and scandium hydroxide are dissolved in strong alkali, the pH of the end point is difficult to accurately control, the recovery rate of scandium is low due to the fact that the pH value is too low, colloidal precipitation is easy to occur due to the fact that the pH value is too high, and the filtering performance is affected. And the reaction is carried out at a higher pH value, so that the slag entering loss of nickel, cobalt and manganese is increased. In chinese patent CN115094229B, the nickel cobalt hydroxide slurry is subjected to reduction leaching, and then the leaching solution is deironized by goethite method, so as to form goethite type precipitate and nickel-cobalt containing solution which adsorb or dope scandium, and scandium is enriched. However, the inventor researches and discovers that the reduction leaching makes manganese divalent, so that the manganese content in the