CN107557579A - A kind of method of extract and separate antimony, iron from acid complicated antimony-containing solution - Google Patents

Abstract

A method for extracting and separating antimony and iron from an acidic complex antimony-containing solution, comprising the following steps: (1) mixing the acidic leaching mother liquor and the extractant uniformly according to the liquid-liquid volume ratio of 1-3:1, and performing extraction; (2 ) liquid-liquid separation after extraction to obtain raffinate and loaded organic phase; (3) mix the loaded organic phase obtained in step (2) with dilute hydrochloric acid for back extraction and regeneration of extractant; after back extraction, separate liquid, separate the organic phase and the aqueous reverse extract; the antimony enters the aqueous reverse extract, and the iron remains in the organic phase. The method of the invention has short process flow, high reaction efficiency and simple operation, and is suitable for the treatment of various acidic antimony-containing solutions, especially for complex acidic solutions containing antimony and iron, and also for complex acidic solutions containing antimony, iron and arsenic. solution.

Description

A method for extracting and separating antimony and iron from acidic complex antimony-containing solution

technical field

The invention relates to the field of metal extraction in solution, in particular to a method for directly treating antimony-containing acidic solution and preparing antimony oxide by an extraction method.

Background technique

In recent years, due to a series of problems in antimony pyro-smelting, hydro-smelting antimony has gradually become the main research direction of scholars at home and abroad. Therefore, the research on antimony-containing leachate obtained by wet process has also been paid more and more attention.

The antimony hydrometallurgy process is divided into two categories: alkaline leaching and acid leaching. Among them, acid leaching mainly uses oxidants to oxidize and decompose antimony sulfide, and uses ligands and antimony ions to form complex ions to enter the solution, so that the antimony element enters the solution in the form of SbCl ₃ and is recovered, while the sulfur element remains in the leaching residue to realize the recovery of antimony. For the acid leaching mother liquor, the traditional treatment method is to produce chemical products such as antimony white through hydrolysis, neutralization and conversion. Since antimony white is the most consumed among various chemical products of antimony, the hydrolysis method avoids the production of metal antimony first and then The process of preparing antimony white shortens the preparation process of antimony white and provides a good idea for antimony smelting. However, the hydrolysis method will produce a large amount of acid wastewater, which not only makes the leaching agent hydrochloric acid unable to be recycled, causes a waste of resources, but also pollutes the environment.

Based on the shortcomings of traditional treatment methods, some scholars have proposed several methods to deal with antimony in acidic leachate:

1. The method of producing metal antimony by direct electrowinning, this method can effectively avoid the generation of acidic wastewater, and can obtain metal antimony by direct electrowinning, but in the actual production process, trivalent antimony ions will be oxidized to pentavalent antimony in the anode chamber price, seriously reducing the current efficiency. Moreover, the electrolysis process is not easy to control, and antimony explosion is easy to occur.

2. Dry distillation method. The principle of this process is to carry out dry distillation of the solution at a temperature higher than the boiling point of SbCl ₃ to dry out volatile components such as SbCl ₃ and SnCl ₄ , while high-boiling chlorides, elemental sulfur and gangue remain in the residue. The chlorination-dry distillation method has the advantages of good separation effect of lead and antimony, small liquid-solid ratio, strong applicability to minerals, the whole process is carried out in a wet system, the equipment can be sealed with negative pressure, and it is environmentally friendly. However, because the process is too complicated, the requirements for equipment are high, and the energy consumption of the production process is high, it is not suitable for large-scale industrial applications.

Aiming at the recovery process of antimony in the acidic system, CN103849902A discloses a "recovery process of antimony and bismuth in copper electrolyte", which is characterized in that the copper electrolyte containing antimony and bismuth is electrolyzed to obtain a loaded organic compound containing antimony and bismuth. phase, using thiourea and sulfuric acid as the stripping agent for stripping, using ammonia water to adjust the pH of the stripping solution, and filtering to obtain a concentrate containing antimony and bismuth. This process effectively recovers antimony and bismuth in the copper electrolyte, but the process is complicated and the process is long, and the product obtained is only the enrichment of antimony and bismuth, and no antimony oxide product is obtained, and further separation and purification are needed The process is difficult to operate.

At present, there is no simple and feasible method for the selective recovery and preparation of antimony oxides from acidic complex antimony-containing solutions.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a method for extracting and separating antimony and iron from acidic complex antimony-containing solutions with short process flow, high reaction efficiency and simple operation.

The technical solution adopted by the present invention to solve the technical problems is: a method for extracting and separating antimony and iron from acidic complex antimony-containing solution, comprising the following steps:

(1) Mix the acidic leaching mother liquor and the extractant according to the liquid-to-liquid volume ratio (i.e., ratio) of 1-3:1, and then extract; the extraction temperature is 15-85°C, and the extraction time is 5-30min;

The antimony content of the acidic leaching mother liquor is 0.10-80g/L, the hydrogen ion concentration is 0.5-4mol/L, the iron content>0g/L, and the arsenic content≥0g/L;

The extractant is a mixture of tributyl phosphate (TBP) and sulfonated kerosene, and the volume content of tributyl phosphate in the extractant is 30-90% (preferably 75-85%).

Tributyl phosphate is the main reagent in the extractant, while sulfonated kerosene is mainly the diluent. If the content of tributyl phosphate is too high, the cost will increase; if the content of tributyl phosphate is too low, the extraction effect will be poor.

(2) Liquid-liquid separation after extraction to obtain raffinate and loaded organic phase;

(3) Mix the loaded organic phase obtained in step (2) with dilute hydrochloric acid for back extraction and regeneration of the extractant; the volume ratio of the loaded organic phase to dilute hydrochloric acid in the back extraction process is 1:1-3; back extraction The temperature is 15-85°C, and the back-extraction time is 5-30 minutes; after the back-extraction is completed, liquid separation is carried out to separate the organic phase and the aqueous phase extraction; the antimony enters the water phase extraction, and the iron remains in the organic phase.

Further, in step (3), the concentration of dilute hydrochloric acid is 1-3 mol/L.

The principle of stripping with dilute hydrochloric acid is to use Cl ^- in hydrochloric acid as a coordination ion to form a coordination balance with antimony ions, so that it can be dissolved in dilute hydrochloric acid, so as to achieve the purpose of stripping. Antimony enters the aqueous phase during stripping, while iron remains in the organic phase. If the concentration of hydrochloric acid is too low, antimony will be hydrolyzed and precipitated; if the concentration of hydrochloric acid is too high, more iron will be dissolved in the aqueous phase of hydrochloric acid, which is not conducive to the separation of antimony and iron; and the concentration of acid is too high, which is not conducive to Subsequent acid treatment. Use other acid also can't reach the purpose of the present invention, as using nitric acid, iron, antimony all can enter stripping solution, can't realize the purpose of separation.

The obtained aqueous reverse extract contains antimony, which can be separated by existing techniques, such as adding NaOH solution to the aqueous reverse extract to hydrolyze the antimony therein to generate antimony oxides.

The percentages mentioned in the present invention are all percentages by mass unless otherwise specified.

Prominent feature and reaction mechanism of the present invention are:

1. The present invention utilizes antimony and iron in the high-acid solution in the form of neutral complexes, and the mixture of neutral extractant tributyl phosphate (TBP) and sulfonated kerosene can effectively extract antimony and iron, and leach antimony and iron from acid If the acidic leaching mother liquor contains arsenic and the arsenic exists in the form of arsenate, the arsenic will remain in the acidic leaching mother liquor;

2. Utilizing the coordination balance of antimony, antimony ions enter the dilute hydrochloric acid aqueous phase during stripping, while iron remains in the organic phase, thereby realizing the separation of antimony and iron.

3. The extraction agent can continue to be extracted and stripped after being regenerated through extraction and stripping. The organic phase contains a small amount of iron ions and needs to be regenerated with dilute sulfuric acid. According to the experimental verification, at least 5 cycles can be carried out, which can effectively reduce costs, reduce the discharge of three wastes, and be environmentally friendly.

The method of the invention has short process flow, high reaction efficiency and simple operation, and is suitable for the treatment of various acidic antimony-containing solutions, especially for complex acidic solutions containing antimony and iron, and also for complex acidic solutions containing antimony, iron and arsenic. solution.

detailed description

The present invention will be described in further detail below in conjunction with specific examples.

Example 1

The raw material of this embodiment is acidic leaching mother liquor-complex antimony-containing sulfide oxidation leach liquor, which is derived from the acidic hydrometallurgical process of antimony. The concentrations of iron and antimony in the solution are 14.5g/L and 4.7g/L respectively, and the acidity is extremely high at 3mol/L, which has a certain recovery value, but the selective recovery is difficult.

The method for extracting and separating antimony and iron from acidic complex antimony-containing solution of the present embodiment comprises the following steps:

(1) Mix the acidic leaching mother liquor and the extractant according to the liquid-to-liquid volume ratio (i.e., the ratio) of 1:1, and then extract; the extraction temperature is 15°C, and the extraction time is 30 minutes;

The extractant is prepared by mixing tributyl phosphate TBP and sulfonated kerosene, wherein the volume content of TBP is 50%.

(2) Liquid-liquid separation is carried out after extraction to obtain raffinate and loaded organic phase. The extraction rate of antimony is 93%, and the extraction rate of iron reaches 99.5%.

(3) Mix the loaded organic phase with dilute hydrochloric acid for back extraction and regeneration of the extractant. In the stripping process, the volume ratio of the loaded organic phase to the dilute hydrochloric acid is 1:1, the stripping temperature is 15° C., and the stripping time is 30 minutes; the stripping agent is dilute hydrochloric acid with a concentration of 3.0 mol/L. After the stripping is completed, liquid separation is carried out to separate the organic phase and the aqueous reverse extract; the antimony enters the aqueous reverse extract, and the iron remains in the organic phase.

The stripping rate of antimony is 92%, and that of iron is 5.2%. The total recovery rate of antimony can reach 85.5%.

Example 2

The raw material of this embodiment is acidic leaching mother liquor-complex antimony-containing sulfide oxidation leach liquor, which is derived from the acidic hydrometallurgical process of antimony. The concentrations of iron and antimony in the solution are 5.5g/L and 41.7g/L respectively, and the acidity is extremely high at 4mol/L, which has high recovery value, but selective recovery is difficult.

The method for extracting and separating antimony and iron from acidic complex antimony-containing solution of the present embodiment comprises the following steps:

(1) Mix the acidic leaching mother liquor and the extractant according to the liquid-to-liquid volume ratio (i.e., ratio) of 2:1, and then extract; the extraction temperature is 50°C, and the extraction time is 15 minutes;

The extractant is prepared by mixing tributyl phosphate TBP and sulfonated kerosene, wherein the volume content of TBP is 70%.

(2) Liquid-liquid separation is carried out after extraction to obtain raffinate and loaded organic phase. The extraction rate of antimony is 90%, and the extraction rate of iron reaches 99.5%.

(3) Mix the loaded organic phase with dilute hydrochloric acid for back extraction and regeneration of the extractant. In the stripping process, the volume ratio of the loaded organic phase to the dilute hydrochloric acid is 1:1, the concentration of the stripping agent dilute hydrochloric acid is 1.5 mol/L; the stripping temperature is 50°C, and the stripping time is 15 minutes; , carry out liquid separation, and separate the organic phase and the aqueous reverse extract; the antimony enters the aqueous reverse extract, and the iron continues to remain in the organic phase.

The stripping rate of antimony was 91.3% and that of iron was 3.4%. The total recovery rate of antimony can reach 82.2%.

Example 3

The raw material of this embodiment is acidic leaching mother liquor-complex antimony-containing sulfide oxidation leach liquor, which is derived from the acidic hydrometallurgical process of antimony. The concentrations of iron and antimony in the solution are 10.5g/L and 25.1g/L respectively, and the acidity is extremely high at 3mol/L, which has a high recovery value, but the selective recovery is difficult.

The method for extracting and separating antimony and iron from acidic complex antimony-containing solution of the present embodiment comprises the following steps:

(1) Mix the acidic leaching mother liquor and the extractant according to the liquid-to-liquid volume ratio (that is, the ratio) of 3:1, and then extract; the extraction temperature is 85°C, and the extraction time is 5 minutes;

The extractant is prepared by mixing tributyl phosphate TBP and sulfonated kerosene, wherein the volume content of TBP is 80%.

(2) Liquid-liquid separation was carried out after extraction to obtain raffinate and loaded organic phase. The extraction rate of antimony was 91.5%, and the extraction rate of iron reached 99.1%.

(3) Mix the loaded organic phase with dilute hydrochloric acid for stripping and regeneration of the extractant; the volume ratio of the loaded organic phase to dilute hydrochloric acid in the stripping process is 1:3, and the concentration of the stripping agent dilute hydrochloric acid is 1.0 mol/L; the stripping temperature is 85°C, and the stripping time is 5min; after stripping, liquid separation is carried out to separate the organic phase and the aqueous phase; antimony enters the aqueous phase, and iron remains in the organic phase .

The stripping rate of antimony is 95.3%, and that of iron is 6.2%. The total recovery rate of antimony can reach 87.2%.

Claims (7)

1. A kind of 1. method of extract and separate antimony, iron from acid complicated antimony-containing solution, it is characterised in that comprise the following steps：

   （1）Acidic leaching mother liquor is well mixed with extractant by liquid liquid volume ratio for 1-3 ︰ 1, extracted；

   The extractant is the mixture of tributyl phosphate and sulfonated kerosene, and the volume content of tributyl phosphate is in extractant 30-90%；

   （2）Liquid liquid Separation is carried out after extraction, obtains raffinate and load organic phases；

   （3）By step（2）Gained load organic phases mix with watery hydrochloric acid, are stripped and the regeneration of extractant；Back extraction knot Shu Hou, liquid separation is carried out, separate organic phase and aqueous phase strip liquor；Antimony enters in aqueous phase strip liquor, and iron continues to stay in organic phase.
2. 2. the method for extract and separate antimony, iron according to claim 1 from acid complicated antimony-containing solution, it is characterised in that Step（1）In, the antimony content of the acidic leaching mother liquor is 0.10-80g/L, and hydrogen ion concentration is 0.5 ~ 4mol/L, iron content ＞ 0g/L, arsenic content >=0g/L.
3. 3. the method for extract and separate antimony, iron according to claim 1 or 2 from acid complicated antimony-containing solution, its feature exist In step（1）In, extraction temperature is 15-85 DEG C, extraction time 5-30min.
4. 4. the method for extract and separate antimony, iron according to claim 1 or 2 from acid complicated antimony-containing solution, its feature exist In step（1）In, the volume content of tributyl phosphate is 75-85% in extractant.
5. 5. the method for extract and separate antimony, iron according to claim 1 or 2 from acid complicated antimony-containing solution, its feature exist In step（3）In, the concentration of watery hydrochloric acid is 1-3 mol/L.
6. 6. the method for extract and separate antimony, iron according to claim 1 or 2 from acid complicated antimony-containing solution, its feature exist In step（3）In, the volume of the back extraction Process Duty organic phase and watery hydrochloric acid is in a ratio of 1：1-3.
7. 7. the method for extract and separate antimony, iron according to claim 1 or 2 from acid complicated antimony-containing solution, its feature exist In step（3）In, back extraction temperature is 15-85 DEG C, back-extraction time 5-30min.