JP2704443B2 - Indium separation and recovery method - Google Patents

Description

The present invention relates to a method for selective separation and recovery of indium.

More specifically, the present invention relates to a method for selectively separating and recovering indium in a solution using a membrane containing a specific hydrophobic compound capable of forming a chelate.

[Conventional technology]

The demand for indium has been increasing remarkably in recent years due to the development of the semiconductor field and the like. Indium, unlike iron and copper, does not have a single ore. Since indium is mainly contained in the zinc ore smelting residue of zinc ore, smoke ash, or in the alkaline leaching residue of bauxite aluminum ore, various measures have been taken for separation and recovery. A lot of effort and money is spent. In other words, with a simple process, there are few adverse effects,
The development of technology that can separate and recover gallium economically and efficiently is expected and has great commercial value. By the way, at present, separation and recovery of indium that is being carried out on an industrial scale,
(1) A method in which aluminum, zinc or cadmium is immersed in the acidic aqueous solution to perform substitution precipitation. (2) A sulfuric acid solution is treated with hydrogen sulfide and hydroxylated, and then treated with zinc or aluminum. Substitution precipitation method (3) Solvent extraction method (4)
An adsorption separation method using a chelate resin having an iminodiacetic acid group as a functional group has been implemented or proposed.

However, each of these methods has various disadvantages. In the methods (1) and (2), if a metal having a low ionization tendency exists due to the added metal, it is impossible to separate indium from the metal.
The solvent extraction method of (3) has a low selectivity in a system in which a large amount of zinc and aluminum coexist and uses a large amount of a solvent. In addition, the method of (4) using an iminodiacetic acid-based chelate resin requires that the selectivity to indium is low and that the rate of contact between the solution containing indium and the chelate resin be finely limited. Considering the price, acid resistance and heat resistance of the chelate resin, it is hard to say that the method is sufficiently satisfactory.

Under these circumstances, despite the remarkable increase in demand for metal indium with the development of the electronics industry, such as the semiconductor sector, separation and recovery of indium that is still economically satisfactory on an industrial scale. The method has not been established. Accordingly, the present inventors have conducted intensive studies to establish a novel method for separating and recovering indium which has overcome the above-mentioned disadvantages. As a result, the present inventors have found that a specific hydrophobic compound capable of forming a chelate is contained, but indium is selectively removed. Adsorption and migration on the surface of the film and desorption on the other surface, and arrived at the present invention.

[Means for solving the problem]

That is, the present invention (However, R ₁ represents a linear, branched or alicyclic alkyl or alkenyl group having 3 to 30 carbon atoms, R ₂ represents a phenylene group, a naphthylene group, a hydrophenylene group or a hydronaphthylene group, and X represents a hydrogen atom. , An inorganic or organic ammonium ion or an alkali metal such as sodium or potassium, and n represents 0, 1, or 2). A film having a hydrophobic compound having an N-nitrosohydroxyamino group represented by the following formula: It is another object of the present invention to provide a method for selectively separating and recovering gallium from a solution containing gallium.

The above used in the present invention Examples of the hydrophobic compound having an N-nitrosohydroxyamino group represented by the formula: R ₁ include, for example, propyl, hexyl, octyl, dodecyl, octadecyl, eicosyl, docosyl, triancontyl, propenyl, hexenyl, octenyl, dodecenyl, octadecenyl, Eicosenyl, docosenyl, trianconenyl, cyclopropyl, cyclohexyl, cyclooctyl, dicyclopropyl, dicyclohexyl, dicyclooctyl, tricyclopropyl, tricyclohexyl, tricyclooctyl, cyclopropenyl, cyclohexenyl, cyclooctenyl, dicyclopropenyl, dicyclohexyl A cyclohexenyl, dicyclooctenyl, tricyclopropenyl, tricyclohexenyl, or tricyclooctenyl group or an equivalent thereof N-nitrosohydroxylamine, N-nitrosophenylhydroxylamine and N-nitrosonaphtylhydroxylamine having an aqueous substituent or hydrogenated products of these phenyl and naphthyl groups and N-nitrosohydroxylamine or inorganic or organic thereof Examples thereof include ammonium salts and alkali metal salts such as sodium and potassium. In particular, N-nitrosophenylhydroxylamine ammonium salt having a hydrophobic substituent or N-nitrosonaphthylhydroxylamine ammonium salt is preferably used.

As the film used in the present invention, the hydrophobic compound is dissolved in a hydrophobic solvent, and a carrier, for example, an impregnated film impregnated in a porous polymer film, an emulsified film stabilized by a surfactant or A blend film prepared by blending the hydrophobic compound with a polymer and forming the film into a film shape can be given. As the hydrophobic solvent used when preparing the impregnated film and the emulsified film, the hydrophobic compound can be dissolved and has a very low solubility in water, for example, kerosene, xylene, diethylbenzene, tetrachloroethane, or diphenyl ether. Or those having the same hydrophobicity as these are preferred. Further, the porous polymer membrane used as a carrier is a membrane-shaped polymer material having a large number of fine through-holes, such as polyethylene, polypropylene, cellulose acetate, Teflon, polyvinyl chloride, polyvinylidene fluoride, polycarbonate, Examples thereof include polysulfone, polyamide, and polyimide. Further, as a carrier that is a membrane material used when preparing a blend membrane, a hydrophobic polymer is preferable, for example, polyethylene, polypropylene, polybutadiene, polymethyl methacrylate,
Polystyrene, polyacrylonidol, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, Teflon, silicone rubber and the like can be mentioned.

The shape of the membrane may be either a flat membrane or a hollow fiber membrane.

The solution containing indium in the present invention is not particularly limited as long as it is an indium-containing solution. For example, an acidic aqueous solution of a leaching residue of sphalerite obtained in an industrial zinc production process, an acidic aqueous solution of a leaching residue of bauxite, which is a raw material of aluminum, and the like can be mentioned.

In order to selectively separate and recover indium from the indium-containing solution according to the present invention, a membrane containing the hydrophobic compound is provided between the indium supply phase solution and the indium permeation phase solution, and the two are brought into contact with each other. For example, a diaphragm method or a hollow fiber membrane method may be employed. The amount of the hydrophobic compound used is appropriately selected depending on the indium concentration on the side of the supply phase solution. The working temperature is 5 to 70 ° C, preferably 10 to
50 ° C. Further, the solution containing indium on the supply side is preferably acidic, and the pH is preferably from about 0 to 5, particularly preferably from 1 to 4. Further, it is preferable to lower the pH on the indium permeate phase solution side or to increase the pressure on the supply phase solution side to increase the permeation rate.

〔The invention's effect〕

According to the present invention, indium can be selectively separated and recovered from a solution containing indium by a simple operation, and the recovered liquid as it is or, for example, is replaced and precipitated with aluminum, and then melted under molten potassium hydroxide and then mixed with indium sulfate. A high-purity metal indium can be obtained by preparing a solution containing salt and performing electrolysis by a known method.

Compared to a method of separating and recovering indium using a known method, indium has high selectivity. In addition, in the present invention, since a membrane is used, in the method using a known chelating agent or chelating resin, indium extraction and elution must be handled as separate processes, but there is an advantage that this can be performed in one process. Its value is great in terms of efficient indium separation and recovery.

Hereinafter, the present invention will be described in more detail with reference to Examples. The present invention is not limited to the following embodiments.

〔Example〕

Examples 1-5 A kerosene solution of a hydrophobic compound having an N-nitrosohydroxyamino group represented by the following general formula was applied to a porous polypropylene flat membrane (average pore size 0.27 μm, porosity 73%) by 0.1 c.
An impregnated membrane (surface area: 6 cm ² , thickness: 30 μm) impregnated with m ³ was prepared.

Indium 115pp adjusted to supply phase (left side) through membrane
m, 50 ml of aqueous solution containing 13000 ppm of zinc and 10000 ppm of aluminum, aqueous solution 5 adjusted to pH 0.5 on the permeate phase side (right side)
0 ml each was charged, and both phases were stirred at room temperature. 48
Table 1 shows the concentrations of indium, zinc and aluminum in the permeation phase (right side) after time.

Example 6 The same operation as in Example 1 was performed except that an N-nitrosophenylhydroxylamine ammonium salt having an n-dodecyl group as a hydrophobic substituent was used as the hydrophobic compound.

Example 7 As a hydrophobic solvent, kerosene / diphenyl ether,
The same operation as in Example 1 was performed except that 7/3 (volume ratio) was used.

Example 8 The same operation as in Example 1 was carried out except that polystyrene was used as the hydrophobic polymer, this and a hydrophobic compound were dissolved in chloroform, and a film formed by a casting method using chloroform as a solvent was used. Table 2 shows the above results.

Comparative Example 1 Instead of using a hydrophobic compound having an N-nitrosohydroxylamino group in which R ₁ is an octadecyl group and R ₂ is a phenyl group used in Example 1, R ₁ is a hydrogen atom and R ₂ is a phenyl group. The same operation as in Example 1 was carried out except that a compound having a certain N-nitrosohydroxyamino group was used. When the metal ion concentration of the permeation phase (right side) after 48 hours was measured, indium, zinc and aluminum were all 3
55 ppm.

Claims (4)

(57) [Claims] (1) (However, R ₁ represents a linear, branched or alicyclic alkyl or alkenyl group having 3 to 30 carbon atoms, R ₂ represents a phenylene group, a naphthylene group, a hydrophenylene group or a hydronaphthylene group, and X represents a hydrogen atom. , An inorganic or organic ammonium ion, or an alkali metal of sodium or potassium, and n represents 0, 1, or 2.) A membrane containing a hydrophobic compound having an N-nitrosohydroxyamino group represented by the following formula: And a method for selectively separating and recovering indium from a solution containing indium. 2. The method for selectively separating and recovering indium according to claim 1, wherein the membrane containing a hydrophobic compound is a membrane in which the surface of a carrier is coated with the hydrophobic compound. . 3. The method for selectively separating and recovering indium according to claim 1, wherein the membrane containing a hydrophobic compound is a membrane comprising a mixture of a hydrophobic compound and a carrier. 4. The method for selectively separating and recovering indium according to claim 1, wherein the solution containing indium is an acidic aqueous solution.