JPH028012B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for recovering indium or gallium.

Currently, idium or gallium is recovered from an aqueous mineral acid solution as a byproduct of the zinc smelting industry, and a solvent extraction method using an alkyl phosphate or an alkyl carboxylic acid is mainly used as a recovery method. However, this solvent extraction method
Due to the large loss of solvent due to migration of the solvent in the aqueous solution, the difficulty in removing extracted idium or gallium, and the complexity of the process, etc.
It cannot be said that it is a highly productive method, and it is difficult to recover efficiently.

In view of these circumstances, the present inventors have intensively investigated methods for recovering indium or gallium from acidic aqueous solutions. As a result, when brought into contact with aminomethylenephosphonic acid derivatives, the aminomethylenephosphonic acid derivatives are combined with idium or gallium in acidic aqueous solutions. The present invention was achieved based on the discovery that indium or gallium in an acidic aqueous solution can be recovered very efficiently by forming a strong solid complex that is insoluble in water.

That is, the present invention is a method for recovering indium or gallium, which is characterized by bringing an acidic aqueous solution containing indium or gallium into contact with an aminomethylenephosphonic acid derivative.

Preferred examples of the aminomethylene phosphonic acid derivatives used in the present invention include the general formula () (In the formula, R ₁ to _{R 4} are each a hydrogen atom and a carbon number of 1
-50 aliphatic hydrocarbon groups, C1-50 aromatic hydrocarbon groups, or some of the hydrogen atoms in these hydrocarbon groups are halogens, carboxyl groups, hydroxyl groups, thiol groups, amino groups, phosphonic acid groups represents a hydrocarbon group substituted with a group selected from the group consisting of aminomethylenephosphonic acid group and aminomethylenephosphonic acid group. ), a compound represented by the general formula () (In the formula, R ₁ to _{R 6} are each a hydrogen atom and a carbon number of 1
-50 aliphatic hydrocarbon groups, C1-50 aromatic hydrocarbon groups, or some of the hydrogen atoms in these hydrocarbon groups are halogens, carboxyl groups, hydroxyl groups, thiol groups, amino groups, phosphonic acid groups represents a hydrocarbon group substituted with a group selected from the group consisting of aminomethylene phosphonic acid group, and n is 1 to 20
represents an integer. ), a compound represented by the general formula () (In the formula, R ₁ to R ₁₂ are each a hydrogen atom and a carbon number of 1
-50 aliphatic hydrocarbon groups, C1-50 aromatic hydrocarbon groups, or some of the hydrogen atoms in these hydrocarbon groups are halogens, carboxyl groups, hydroxyl groups, thiol groups, amino groups, phosphonic acid groups n and m represent a hydrocarbon group substituted with a group selected from the group consisting of
Each represents an integer from 1 to 20. ). Specific examples of these compounds include the following.

(1) n-butylamine-N,N-bis(methylenephosphonic acid), (2) n-nonylamine-N,N-bis(methylenephosphonic acid), (3) hexamethylenediamine-N,N,N', N'-tetrakis (methylenephosphonic acid), (4) 2-ethylhexylamine-
N,N-bis(methylenephosphonic acid), (5)benzylamine-N,N-bis(methylenephosphonic acid),
(6)m-xylenediamine-N,N,N',N'-tetrakis(methylenephosphonic acid), (7)(P-nonylbenzyl)amine-N,N-bis(methylenephosphonic acid), (8) Dibenzylamine-N-methylenephosphonic acid, (9) N-carboxymethylnonylamine-N-methylenephosphonic acid, (10) N-carboxymethylamine-N-methylenephosphonic acid, (11) N-
Methylcaptomethylnonylamine-N-methylenephosphonic acid, (12) N,N-bis(O-hydroxybenzyl)amine-N-methylenephosphonic acid, (13)
Tyrosine-N,N-bis(methylenephosphonic acid),
(14) (3,5-dichloro-4-hydroxyphenyl)glycine-N,N-(methylenephosphonic acid), To obtain the aminomethylenephosphonic acid derivative used in the present invention, for example, a compound containing a primary or secondary amino group (e.g., P-aminomethylphenol) is reacted with chloromethylenephosphonic acid, or a primary Alternatively, it can be easily synthesized by reacting formalin and phosphorous acid with a mineral acid aqueous solution on a compound containing a secondary amino group. Specific conditions at this time include, for example, a compound containing a primary or secondary amino group and phosphorous acid in a molar ratio of 1:0.8n to 2n (n is a compound containing a primary or secondary amino group). represents the number of hydrogen atoms directly connected to the hydrogen atom of the compound).
After adding a 1-36N mineral acid aqueous solution to make a homogeneous solution, heat it to 90℃-130℃ and reflux, and in this state, add 0.8n-6nmol of formalin over 1 hour to 2 hours. Drip. Next, after the completion of dripping, 1 more
Heating may be continued under reflux for ~5 hours, after which water may be distilled off or the product may be filtered. Also,
When a compound containing a primary or secondary amino group also contains a phenolic hydroxyl group, when this compound is treated with phosphorous acid and formalin, the phenolic hydroxyl group is simultaneously oxidized with methylene phosphonation of the amino group. The O-position or P-position also reacts with formalin, and the compounds (15), (18), and (19) shown above can also be obtained.

In the present invention, any method may be used to bring the acidic aqueous solution containing indium or gallium into contact with the aminomethylenephosphonic acid derivative, but the aminomethylenephosphonic acid derivative is dissolved in an alkaline aqueous solution and the acidic aqueous solution containing indium or gallium is brought into contact with the aminomethylenephosphonic acid derivative. It is preferable to add it to an acidic aqueous solution.
The concentration of the aminomethylenephosphonic acid derivative at this time is, for example, 0.1 to 30% by weight, preferably 1 to 10% by weight, and the alkaline aqueous solution is, for example, 0.1 to 5N sodium hydroxide,
Aqueous solutions such as potassium hydroxide and ammonium hydroxide are preferred. In addition, the amount to be added is, for example, 0.01× by weight relative to indium or gallium.
W/n ~ 0.08 x W/n times (W is the molecular weight of the aminomethylene phosphonic acid derivative, n represents the number of phosphonic acid groups contained in one molecule) is appropriate, and 0.02 x W/n ~ 0.05 ×W/n times the amount is preferable. Furthermore, the appropriate temperature for addition is, for example, 10°C to 70°C, especially 40°C.
The temperature is preferably from 0.degree. C. to 60.degree. C., and the appropriate time is, for example, within 1 hour.

By doing this, a water-insoluble complex (a complex of indium or gallium and an aminomethylenephosphonic acid derivative) is precipitated, and by filtering this precipitate, indium or gallium is recovered. At this time, any method may be used to recover indium or gallium from the separated complex, but it is preferable to add the alkali aqueous solution described above to this complex. When this alkaline aqueous solution is added, indium or gallium hydroxide precipitates, and by filtering this precipitate, indium or gallium and the alkaline aqueous solution containing the aminomethylenephosphonic acid derivative are separated and recovered. be able to. It is also possible to recover indium or gallium as an indium or gallium oxide by incinerating the complex, but since the aminomethylenephosphonic acid derivative decomposes, the aminomethylenephosphonic acid derivative cannot be reused. I don't like it very much because it disappears.

As the acidic aqueous solution containing indium or gallium targeted by the present invention, for example, an aqueous solution of a mineral acid such as sulfuric acid, hydrochloric acid, nitric acid, or phosphoric acid (with a concentration of approximately 0.1 to 0.5N) is effective. This acidic aqueous solution containing indium or gallium may contain any metal ions as coexisting metal ions, including Zn ²⁺ , Cu ²⁺ , Pb ²⁺ ,
It is particularly effective when containing Cd ²⁺ etc.
These metal ions hardly form a complex with the aminomethylenephosphonic acid derivative in the above mineral acid aqueous solution.

According to the present invention, indium or gallium in an acidic aqueous solution can be recovered extremely efficiently.

Next, the present invention will be specifically explained using examples.

Reference Example 1 (Synthesis of aminomethylenephosphonic acid derivative) 1 mole of p-aminomethylphenol, 2 moles of phosphorous acid, and 6 moles of formalin were dissolved in 6N hydrochloric acid at 120%
The mixture was reacted at ℃ for 6 hours to obtain a formalin condensate of (p-hydroxybenzyl)amine-N,N-bis(methylenephosphonic acid).

Reference Example 2 (Synthesis of aminomethylenephosphonic acid derivative) After reacting 1 mole of diethylenetriamine, 1 mole of 2,6 dimethylphenol, and 1 mole of formalin at 70°C for 2 hours, 6N hydrochloric acid was added to make an acidic solution. Further, 2 moles of phosphorous acid and 4 moles of formalin were added and reacted at 120°C for 4 hours to obtain the above (16).
The compound represented by was obtained.

Reference Example 3 (Synthesis of aminomethylenephosphonic acid derivative) 1 mole of n-nonylamine, 1 mole of phosphorous acid, and 2 moles of formalin were reacted in 6N chlorine at 120°C for 2 hours to form n-nonylamine-N,N. -bismethylenephosphonic acid) was obtained.

Example 1 Mix 10 g of each of the aminomethylene phosphonic acid derivatives obtained in Reference Examples 1, 2, and 3 with 4 g of caustic soda, add water to make 10 c.c., and prepare a mixture containing three types of amino methylene phosphonic acids. An aqueous solution was prepared.

These aqueous solutions are designated as A (Reference Example 1), B (Reference Example 2), and C (Reference Example 3), respectively.

Next, 100PPM of In was contained, and other coexisting metal ions were Zn50g/, Cd10g/, Pb0.1g/
, Cu0.2g/, Fe0.5g/, and
Aqueous solutions containing 10 g/H ₂ SO ₄ were prepared from the respective metal sulfates and concentrated sulfuric acid.

This aqueous solution is designated as D.

Next, 10 c.c. of each of the above solutions A, B, and C were added to this solution D 1 separately. A pale yellow precipitate was formed at the moment of addition, and in this state the mixture was treated at 60°C for 30 minutes with gentle stirring. Thereafter, the precipitate was separated by filtration, and the In concentration of the filtrate was measured by atomic absorption spectrometry.

As a result, 2.5ppm for liquid A and 2.5ppm for liquid B.
5ppm, in the case of C liquid, it is 6.3ppm, A, B, C
It is clear that In is efficiently separated from both the liquid and the liquid.

On the other hand, after washing the separated precipitate with water and air drying, 10 c.c. of 1N caustic soda solution was added thereto, and a precipitate of indium hydroxide was formed. By separating this precipitate by filtration, In and Solutions A, B, and C (aqueous solutions of aminomethylenephosphonic acid derivatives) could be separately recovered.

In the case of A, the In recovered at this time was 97 mg;
In the case of B, the recovery rate was 95 mg, and in the case of C, 93 mg, which was close to 100%. In addition, the recovered A, B,
Liquid C was recyclable.

Example 2 Contains 50 ppm of In, contains 100 g of Zn and 1 g of Cu as other coexisting metal ions, and
Solutions containing 5 g/HCl were prepared from the respective metal hydrochlorides and concentrated hydrochloric acid.

This aqueous solution is designated as E.

Next, in this E solution 1, A, B containing the aminomethylene phosphonic acid derivative obtained in Example 1,
5 c.c. of Solution C was added to each separately. Thereafter, the same operation as in Example 1 was performed, and the In concentration of the filtrate was measured by atomic absorption spectrometry.

As a result, for liquid A, it was 1.2ppm, and for liquid B, it was 1.2ppm.
In the case of liquid C, it was 3 ppm, and it is clear that In was efficiently separated from liquids A, B, and C.

On the other hand, the separated precipitate was subjected to the same operation as in Example 1, and In and liquids A, B, and C could be separately recovered.

In the case of A, the In recovered at this time was 48 mg;
In case of B, 48mg, in case of C, 47mg, almost 100%
The recovery rate was close to . In addition, the recovered A,
Liquids B and C were reusable.

Example 3 Contains 100 ppm of Ga, and other coexisting metal ions, including Zn50g/, Cu0.2g/, and
A solution containing 10 g/H ₂ SO ₄ was prepared from each metal sulfate and concentrated sulfuric acid.

This aqueous solution will be referred to as Solution F.

Next, in this F solution 1, A, B containing the aminomethylene phosphonic acid derivative obtained in Example 1,
10 c.c. of Solution C was added to each separately. Thereafter, the same operation as in Example 1 was performed, and the Ga concentration of the filtrate was measured by atomic absorption spectrometry.

As a result, for liquid A, it was 3.2ppm, and for liquid B,
6.1ppm, in case of C liquid, it becomes 7.0ppm, A, B,
It is clear that Ga is efficiently separated from both liquid C and liquid C.

On the other hand, the separated precipitate was subjected to the same operation as in Example 1, and Ga and liquids A, B, and C could be recovered separately.

At this time, the recovered Ga was 96 mg in case of A;
In case of B, 93mg, in case of C, 93mg, almost 100%
The recovery rate was close to . In addition, the recovered A,
Liquids B and C were reusable.

Claims (1)

[Claims] 1. A method for recovering indium or gallium, which comprises bringing an acidic aqueous solution containing indium or gallium into contact with an aminomethylenephosphonic acid derivative.