JPH0778264B2 - Rare metal recovery method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for recovering a rare metal with a chelate resin having a specific functional group, and more specifically, a solution containing a rare metal and a phosphorus atom-containing functional group. The present invention relates to a method for recovering a rare metal, which comprises contacting a chelating resin having a group.

Rare metals are metals that are useful as new materials in the electronics industry, nuclear industry, chemical industry, etc.

<Prior art> As a method for producing and recovering these rare metals, leaching treatment is performed from minerals containing rare metals with mineral acids, alkalis, water, etc., followed by separation and concentration by precipitation separation method and solvent extraction method. The general method is electrolysis or direct reduction.

<Problems to be Solved by the Invention> Since the amount of rare metals contained in ores is generally small, the concentration of rare metals in the leachate is often low. Since the precipitation separation method is restricted by the solubility of the precipitate, it has the drawback that it cannot be quantitatively precipitated and recovered when the concentration of the target substance is extremely low.
Further, the solvent extraction method has problems to be solved such as dissolution of the solvent in water and loss of the extracting agent due to repeated use.

Thus, when treating a target solution having a low concentration of a rare metal, it is difficult to quantitatively recover the solution, and there are drawbacks in terms of economy and environment.

In view of such circumstances, the present inventors have conducted investigations to develop a method for recovering a rare metal from a solution that overcomes the above inconveniences, and as a result, contain a chelate resin having a specific functional group and a rare metal. It was found that the rare metal in the solution can be recovered at a high recovery rate by bringing it into contact with the solution,
The present invention has been completed.

<Means for Solving the Problem> That is, the present invention, in recovering a rare metal from a solution containing a rare metal, a phosphine group, a phosphonium group, a phosphinic acid group, a phosphinic acid ester group, a phosphonic acid group, a phosphon Another object of the present invention is to provide a method for recovering a rare metal, which comprises contacting with a chelate resin having at least one type of phosphorus atom-containing functional group selected from acid ester groups and metal salts of these acids.

As the solution containing the rare metal, which is the object of the present invention, an acidic or basic aqueous solution is usually applied.

As the solution containing such a rare metal, a mineral acid solution such as ore, ore slag or scrap containing a rare metal, sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid or ammonia,
A leachate in which a rare metal element is eluted is generally applied by performing contact treatment with an aqueous amine solution such as diethylamine, ethylenediamine, diethylenetriamine at room temperature to 100 ° C under normal pressure or pressure, but a solution containing a rare metal. If so, it is not particularly limited.

The rare metal to be the subject of the present invention is not particularly limited and can be applied to any rare metal, but particularly rubidium, cesium, strontium, yttrium, niobium, tantalum, ruthenium, osmium, rhodium, iridium. , Palladium, platinum and europium are preferred.

The chelate resin preferably used in the above-mentioned method of the present invention is a chelate resin having a phosphorus atom-containing functional group, and the following are generally mentioned.

(1) Lithium diphenylphosphine and sodium diphenyl are added to polymers such as styrene-divinylbenzene copolymer, phenol resin, polyethylene and polypropylene containing halogenated alkyl groups such as chloromethyl group and bromomethyl group or halogen atoms such as bromine and iodine. A chelate resin having a phosphine group or a phosphonium base obtained by reacting a phosphine compound such as phosphine, lithium phenylphosphine, or tricresylphosphine, or a mixture thereof.

(2) A styrene-divinylbenzene copolymer containing a halogenated alkyl group such as a chloromethyl group and a bromomethyl group, a phenol resin, an aniline resin, an m-phenylene polymer (hereinafter referred to as a resin having a halogenated alkyl group. ) A chelate resin having a phosphonic acid ester group obtained by reacting) with a phosphorous acid derivative such as triethyl phosphite, triphenyl phosphite, trimethyl phosphite, or a mixture thereof (hereinafter, referred to as phosphorous acid derivative).

(3) A chelate resin having a phosphonic acid group obtained by hydrolyzing a chelate resin having a phosphonate ester group or a chelate resin having a phosphonium base.

(4) A chelate resin having a phosphinic acid group obtained by reacting styrene-divinylbenzene copolymer, polystyrene or the like with phosphorus trichloride and then hydrolyzing the same.

(5) A chelate resin having a phosphinic acid ester group, which is obtained by reacting a resin having an amino group with a chloromethylphosphinic acid ester.

(6) A chelate resin containing a metal salt of the above-mentioned acid such as an alkali metal such as sodium, potassium and calcium, or an alkaline earth metal.

In particular, a chelate resin in which a phosphorus atom-containing functional group is bonded to the polymer main chain via an amino group is preferably used because it forms a strong chelate bond with a rare metal, and the following are generally mentioned.

(A) Halogenated alkylphosphonic acid or phosphinic acid such as diethyl chloromethylphosphonate, ethyl chloromethylphosphonate, diphenyl chloromethylphosphonate, dicresyl chloromethylphosphonate, and ethyl chloromethylphosphinate on a resin having a primary or secondary amino group. A chelate resin having an aminoalkylenephosphonic acid or phosphinic acid ester group obtained by reacting an ester or a mixture thereof.

(B) Other than hydrolyzing the chelating resin having the aminoalkylenephosphonic acid or phosphinic acid ester group, or changing the phosphorous acid derivative used in the production of the resin having the aminoalkylenephosphonic acid or phosphinic acid ester group to phosphorous acid Is a chelating resin having an aminoalkylenephosphonic acid or phosphinic acid group obtained by reacting in exactly the same manner.

The method of contacting the chelate resin produced by the above method with the solution containing the rare metal is not particularly limited, and for example, a method of passing the solution containing the rare metal into the column filled with the chelate resin. A method in which a chelate resin is immersed in a solution containing a rare metal and then separated by filtration is adopted.

The contact temperature of the solution containing the chelate resin and the rare metal is not particularly limited and is usually in the range of 0 to 100 ° C. The contact time is also not particularly limited.

The rare metal adsorbed by the chelate resin of the present invention can be eluted and recovered by using an appropriate eluent. As the eluent, an aqueous solution of a mineral acid such as nitric acid, sulfuric acid, hydrochloric acid or phosphoric acid having a suitable concentration or an aqueous base solution such as sodium carbonate, sodium hydrogen carbonate or sodium hydroxide is generally used. However, a chelate resin is bound to a rare metal. When it is strong, elution and recovery can be performed by using a system of a combination of an oxidizing agent and a mineral acid, a system of a reducing agent and a mineral acid, or a system of a reducing agent and a base, if necessary.

A solution in which rare metals are eluted (hereinafter abbreviated as eluent).
Varies depending on the type of metal and the application, but it may be subjected to treatments such as neutralization and filtration to recover as metal hydroxides, reduction treatment with a reducing agent with the eluent as it is, or eluent The metal can be recovered by electrolysis.

The chelate resin after eluting the rare metal in this manner is used as it is, or if necessary, water and / or a basic aqueous solution of sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, ammonia, hydrochloric acid,
After treatment with an acidic aqueous solution of sulfuric acid, nitric acid, phosphoric acid or the like, it can be repeatedly used again as an adsorbing and collecting agent for rare metals.

<Effects of the Invention> According to the method of the present invention described in detail above, it becomes possible to directly collect and recover a rare metal contained in a solution such as a mineral acid solution, and to adjust the pH of the mineral acid during the recovery process. Alkali treatment is not required and the process can be simplified. PH at the same time
It is also possible to eliminate the problem of alkali consumption used for adjustment.

Furthermore, the chelate resin used in the method of the present invention has a high metal adsorption rate and can collect rare metals existing in a relatively low concentration in a strong acid solution, and its industrial value is extremely large.

<Examples> The present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples without departing from the gist thereof.

Example 1 200 ml by weight of chloromethylated polystyrene was reacted with 500 parts by weight of triethyl phosphite in a toluene solvent, and 10 ml of a resin having a phosphonate group (hereinafter, this polymer is referred to as chelate resin A) was obtained. It was packed in a 12 mmφ column, and 100 ml of a 2N sulfuric acid aqueous solution having a palladium concentration of 98.6 ppm (palladium content 9.8 mg) was passed through the column for 2 hours. When the palladium in the effluent was analyzed, 8.8 mg of palladium was adsorbed.

Examples 2 to 10 Chelate resin B; Duolite ES-63 (resin having a phosphonic acid group; manufactured by Diamond Shamrock) Chelate resin C; 60 parts by weight of polyacrylonitrile is reacted with 103 parts by weight of diethylenetriamine in a water solvent. A resin having an aminoalkylenephosphonic acid ester group obtained by reacting the obtained aminated polyacrylonitrile with 281 parts by weight of an aqueous formalin solution and 498 parts by weight of triethyl phosphite in the presence of 36% hydrochloric acid.

Chelate resin D: A resin having a quaternary phosphonium base obtained by reacting 200 parts by weight of chloromethylated polystyrene and 200 parts by weight of tributylphosphine in a dimethylformamide solvent.

Chelate resin E: A resin having a quaternary phosphonium base obtained by reacting 200 parts by weight of chloromethylated polystyrene and 260 parts by weight of triphenylphosphine in a dimethylformamide solvent.

Chelate resin F; 1.6 parts by mole of n-butyllithium-hexane solution of 1.6 mol% in tetrahydrofuran solvent containing 150 parts by weight of brominated polystyrene.
Lithium polystyrene was obtained by reacting with parts by weight.

A resin having a phosphine group obtained by reacting this with 300 parts by weight of chlorodiphenylphosphine in a tetrahydrofuran solvent and further oxidizing it with 371 parts by weight of 40% peracetic acid in a methylene chloride solvent.

Chelate resin G; a resin having a sodium salt of phosphonic acid obtained by hydrolyzing chelate resin D in a 20% aqueous sodium hydroxide solution.

Chelate resin H: A resin having a phosphinic acid group obtained by reacting 100 parts by weight of polystyrene with 150 parts by weight of phosphorus trichloride in a chloroform solvent, followed by hydrolysis reaction.

Chelate resin I: A resin having a phosphinic acid ester group obtained by reacting 100 parts by weight of aminated polystyrene with 120 parts by weight of cresyl chloromethylphosphinate in a solvent of 1,2-dichloroethane.

Chelate resin J; Sumichelate MC-95 (resin having aminomethylenephosphonic acid group; manufactured by Sumitomo Chemical Co., Ltd.) 10 ml of each of the above chelate resins was packed in a column having an inner diameter of 12 mmφ, and the ruthenium (Ru) concentration was 98.0 ppm
0.5 ml of hydrochloric acid aqueous solution 100 ml (ruthenium content 9.8 mg) 1
The solution was passed in time. Analysis of ruthenium in the effluent,
When the amount of adsorption was determined, the results shown in Table 1 were obtained.

Comparative Examples 1 to 3 In place of the chelate resin used in Examples 2 to 10, Sumichelate MC-30 (a chelate resin having an iminodiacetic acid group; manufactured by Sumitomo Chemical Co., Ltd.), Sumichelate Q-10R.
(A chelate resin having a dithiocarbamic acid group; manufactured by Sumitomo Chemical Co., Ltd.) and Dowex 50W (strongly acidic ion exchange resin; manufactured by Dow Chemical Co.) were used to adsorb ruthenium in the same manner as in Examples 2 to 10. The results shown in Table 2 were obtained.

Examples 11-23, Comparative Examples 4-16 5 ml of the chelate resin J described above was contacted with 100 ml of a mineral acid solution containing a rare metal shown in Table 3 for 5 hours, and the rare metal before and after the treatment was treated. Was determined. The results are shown in Table 3.

Further, the same operation as above was carried out using Sumichelate MC-10 (manufactured by Sumitomo Chemical Co., Ltd.), which is a chelate resin having an oriethylene polyamino group, to determine the concentration of the rare metal. The results are also shown in Table 3.

Claims (2)

[Claims] 1. Rubidium, cesium, strontium,
Yttrium, niobium, tantalum, ruthenium, osmium, rhodium, iridium, palladium, platinum,
A solution containing at least one rare metal of europium is at least one selected from a phosphine group, a phosphonium base, a phosphinic acid group, a phosphinic acid group, a phosphinic acid ester group, a phosphonic acid group, a phosphonic acid group, and a phosphonic acid ester group. A method for recovering a rare metal, which comprises contacting with a chelate resin having a phosphorus atom-containing functional group as described above. 2. The method for recovering a rare metal according to claim 1, wherein the phosphorus atom-containing functional group of the chelate resin is bound to the polymer main chain via an amino group.