JPH0522647B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for separating gallium in an aqueous aluminate solution. [Prior Art] In recent years, various methods using chelate resins have been proposed as methods for recovering gallium from aqueous aluminate solutions during alumina production. A method for recovering gallium using this type of chelate resin is a cyclic compound in which a thiol group, a hydroxyl group, a dithiocarbamate group, or an aminoalkylene phosphate group are bonded together. A method using a chelate resin (JP-A-59-169928), a method using a chelate resin having an amidoxime group or its metal salt as a functional group (JP-A-58-49620), styrene-divinylbenzene copolymer , phenolic resin, vinyl chloride resin, etc. with hydroxylamine, diethylenetriamine, guanidine, hydrazine,
N, O, S obtained by reacting acetylacetone etc.
A method of adsorbing gallium onto a chelate resin containing a plurality of Lewis basic atoms, such as chelate resin, washing the resin with water or dilute acid, and then eluting gallium from the resin with concentrated acid to recover it (Unexamined Japanese Patent Publication No. Showa 59-
169933) etc. are known. [Problems to be solved by the invention] However, the chelate resins conventionally used for gallium recovery do not necessarily have sufficient gallium selectivity and adsorption properties, and it is difficult to improve the gallium recovery rate. That was what was hoped for.
Moreover, the acid and alkali resistance of conventional chelate resins is not sufficient, and in particular, the functional groups of chelate resins having amidoxime groups or their salts as functional groups are easily attacked by acids and alkalis, so the adsorbed gallium If the process of acid washing and recovery is repeated, the adsorption of gallium decreases, making it difficult to use the resin repeatedly. On the other hand, according to the method described in JP-A No. 59-169933, the resin is not easily attacked by acid washing when eluting adsorbed gallium, and repeated use of the resin improves the adsorption properties of gallium. However, as a pre-process to elute the adsorbed gallium with concentrated acid, it is necessary to wash the resin with water or dilute acid to remove the alkali contained in the resin. This method has the disadvantage that the process for recovering gallium is complicated. The present invention has been developed in view of the above points, and has excellent selectivity and adsorption properties for gallium in aqueous aluminate solutions, enables separation of gallium with a high recovery rate, and facilitates the recovery operation of gallium adsorbed on resin. The purpose of the present invention is to provide a method for separating gallium in an aqueous aluminate solution that can be carried out in the following manner. [Means for Solving the Problems] As a result of intensive research in order to solve the above problems, the present inventors have found that the present inventors have a specific resin matrix and an aminoalkylene phosphate group, an iminoalkylene phosphate group, an alkylene phosphate group, or Gallium in an aluminate aqueous solution can be effectively separated by using a chelate resin having a salt as a functional group directly bonded to the resin matrix, and these chelate resins have acid resistance and alkali resistance. The present inventors have completed the present invention by discovering that the resin can be used repeatedly, and the gallium adsorbed to the resin can be recovered with a simple operation. That is, the present invention uses a gallium-containing aluminate aqueous solution as a base resin of either a divinylbenzene copolymer, an epoxy resin, a phenol resin, a resorcinol resin, or a vinyl chloride resin, and an aminoalkylene phosphate group or an iminoalkylene phosphate group. basis,
An aluminate aqueous solution characterized in that the aluminate aqueous solution is brought into contact with a chelate resin having at least one alkylene phosphate group or a salt thereof as a functional group directly bonded to the resin matrix, and gallium is adsorbed to the chelate resin and separated. The gist of this article is a method for separating gallium in The resin base of the chelate resin used in the present invention includes divinylbenzene copolymer, epoxy resin, resorcinol resin, phenol resin,
Examples of the divinylbenzene copolymer include styrene-divinylbenzene copolymer, methyl acrylate-divinylbenzene copolymer, methyl methacrylate-divinylbenzene copolymer, and acrylonitrile-divinylbenzene copolymer. etc. The chelate resin in the present invention uses the above-mentioned resin as a resin base, and contains at least one of an aminoalkylene phosphate group, an iminoalkylene phosphate group, an alkylene phosphate group, or a salt thereof, such as an alkali metal salt or an alkaline earth metal salt.
This is a chelate resin having a species as a functional group directly bonded to the resin matrix, and in particular, the resin matrix is a divinylbenzene copolymer such as a styrene-divinylbenzene copolymer or an epoxy resin, and an aminoalkylene phosphate group or its A chelate resin having a salt or an iminoalkylene phosphoric acid group or a salt thereof as a functional group directly bonded to the resin matrix is preferred. Further, the chelate resin having these functional groups is preferably of a porous type (MR type) rather than a gel type. The reason is that when organic matter is present in the treated water, the metal adsorption ability of gel-type chelate resin decreases, whereas MR
This is because the adsorption capacity of type chelate resins is less likely to decrease, and there is less loss due to resin crushing due to volume changes that occur during resin regeneration. Examples of the above chelate resin include ammonia or polyalkylene such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine after reacting chloromethyl ether with styrene-divinylbenzene copolymer to chloromethylate the styrene-divinylbenzene copolymer. A primary or secondary amino group is introduced by reacting a polyamine, and then an aldehyde such as formaldehyde or acetaldehyde is reacted with phosphorous acid to form an aminoalkylene phosphoric acid group or iminoalkylene phosphoric acid group into the primary or secondary amino group. A chelate resin in which a chloromethylated styrene-divinylbenzene copolymer is reacted with phosphorus trichloride in the presence of aluminum chloride to form a methyl phosphate group (or a methyl phosphate group and a phosphoric acid group) on the benzene core of divinylbenzene. ) formed chelate resin; after reacting polyalkylene polyamine to vinyl chloride resin to introduce a primary or secondary amino group, aldehyde and phosphorous acid are reacted to form an aminoalkylene phosphate group or iminoalkylene on the amino group. Chelate resin with phosphoric acid groups formed; after reacting with a polyalkylene polyamine on the methyl ester group portion of methyl acrylate-divinylbenzene copolymer or methyl methacrylate-divinylbenzene copolymer, aldehyde and phosphorous acid are reacted. A chelate resin in which an aminoalkylene phosphoric acid group or an iminoalkylene phosphoric acid group is formed on the amino group of the polyalkylene polyamine introduced into the methyl ester group; Alternatively, a compound having an iminoalkylene phosphate group is obtained, and this compound is reacted with phenol or resorcinol in the presence of an aldehyde. and alkaline metal salts such as sodium salts and potassium salts, and alkaline earth metal salts such as calcium salts and magnesium salts of the above resins. Among these chelate resins, the above-mentioned chelate resins are preferable, and in particular, after reacting a chloromethylated styrene-divinylbenzene copolymer with a polyalkylene polyamine, aldehyde and phosphorous acid are reacted to form a primary amino group,
Chelate resins in which an aminoalkylene phosphate group or an iminoalkylene phosphate group is formed as a functional group in the secondary amino group portion are preferred. In the present invention, the aluminate aqueous solution includes:
An aqueous solution of sodium aluminate is mainly used, and the method of bringing the aluminate aqueous solution into contact with the above-mentioned chelate resin includes, for example, immersing the chelate resin in an aluminate aqueous solution containing gallium, or a batch method in which the chelate resin is immersed and further stirred. Examples include a column method in which an aluminate aqueous solution is passed through a column packed with a chelate resin, and in the case of a column method, either an upward flow method or a downward flow method can be adopted as the liquid passing method. In addition, in the column type, there are two methods: a slow flow rate of SV0.5 to 10 to adsorb gallium, a fast flow rate of SV10 to 50 to adsorb gallium, or a method to circulate an aluminate aqueous solution to adsorb gallium. Various adsorption methods can be used. The gallium adsorbed on the chelate resin and separated from the aluminate aqueous solution as described above is eluted by treating the chelate resin that has adsorbed gallium with an acid such as hydrochloric acid, sulfuric acid, nitric acid, or phosphoric acid as an eluent. It can be recovered. The adsorbed gallium may be eluted using an eluent such as an acid by either a batch method or a column method. In the case of a column type, elution can be carried out by slowly passing the eluent at a flow rate of SV 0.5 to 5 or by circulating the eluent. Moreover, if the obtained eluent is reused as the next eluent, the gallium concentration in the eluent can be increased. The gallium eluted from the chelate resin can be recovered as metallic gallium, for example, by electrolysis as an aqueous solution of sodium aluminate. Further, the chelate resin after eluting gallium can be repeatedly used for adsorption of gallium in an aqueous aluminate solution. [Example] Hereinafter, the present invention will be explained in more detail with reference to Examples. Example 1 An MR type spherical resin (10 to 60 mesh) made of a styrene-divinylbenzene copolymer obtained by suspension polymerization of 92 wt% styrene and 8 wt% divinylbenzene was swollen in ethylene dichloride and anhydrous chlorinated. The spherical resin was chloromethylated by reacting chloromethyl ether in the presence of zinc (chlorine content: 21.8 wt%). Next, the obtained chloromethylated resin was reacted with diethylenetriamine (DETA) to obtain a DETA type resin having a primary amino group and a secondary amino group. This resin is reacted with orthophosphorous acid and paraformaldehyde in an aqueous hydrochloric acid solution to form an MR type chelate with aminomethylene phosphate groups and iminomethylene phosphate groups as functional groups at the primary and secondary amino groups. Resin was obtained. This chelate resin was classified, and 100ml of resin with 10 to 48 meshes was packed into a column (inner diameter 25mm), and the column was filled with a sodium aluminate aqueous solution (Ga: 150ppm, Al: 20300ppm, NaOH: 18%).
The liquid was passed in a downward flow at a flow rate of SV5. Each time the flow rate shown in Table 1 was reached, a 100 ml sample of the effluent was taken and the metal ion concentration was measured. Results first
Shown in the table. Furthermore, when the amount of liquid passed per liter of resin is 60 liters (hereinafter, the unit of the amount of liquid passed per liter of resin is expressed as l/l-R), the amount of gallium adsorbed to the chelate resin is 8.8 per liter of resin. g (hereinafter, the unit of adsorption amount per liter of resin is expressed as g/l-R),
The adsorption recovery rate was 98%. Next, after extruding the sodium aluminate aqueous solution remaining in the column with water, a 3N- _HNO3 aqueous solution was passed in a downward flow at a flow rate of SV2 in an amount 5 times the resin volume (500 ml) to be adsorbed on the chelate resin. As a result of eluating the gallium and measuring the gallium ion concentration in the eluent, 99.8% of the gallium adsorbed on the chelate resin was recovered by elution. Example 2 The same chloromethylated resin as in Example 1 was reacted with phosphorus trichloride in the presence of aluminum chloride to obtain a chelate resin having phosphoric acid groups and methylene phosphoric acid groups as functional groups. Sodium aluminate aqueous solution (Ga: 52.5ppm, Al: 20100ppm, NaOH: 18%) was added to 0.51ml of 10 to 48 mesh resin classified from this resin.
After adding 250 ml and shaking for 1.5 hours, the gallium ion concentration in the aqueous solution was measured, and the amount of gallium adsorbed on the chelate resin was 7.8 g/l-R. Example 3 A reaction product obtained by reacting tetraethylenepentamine with orthophosphorous acid and formaldehyde was reacted with resorcinol and formaldehyde, and then suspension polymerized in a polyvinyl alcohol solution to obtain a spherical cured resin. Ta. This chelate resin had an iminomethylene phosphate group as a functional group. Then 10 to 48 of the obtained chelate resins
The mesh resin was added to an aqueous sodium aluminate solution and shaken in the same manner as in Example 2. The amount of gallium adsorbed to the chelate resin is 8.5g/l-R
It was hot. Example 4 Polyvinyl chloride crushed into 10 to 50 meshes was swollen with perchlorethylene and then reacted with triethylenetetramine (TETA) to form TETA.
A mold resin was obtained. This resin was reacted with acetaldehyde and orthophosphorous acid to obtain a chelate resin having aminoethylene phosphoric acid groups and iminoethylene phosphoric acid groups as functional groups. 10 of these chelate resins
Add 100 ml of the same sodium aluminate aqueous solution as in Example 1 to 10 g of ~48 mesh resin and heat at 25°C.
After shaking for an hour, the concentration of gallium and aluminum in the solution was measured: Ga: 3.1ppm.
Al: 20300ppm. Comparative Example 1 The same chloromethylated resin as in Example 1 was reacted with ethylenediamine (EDA) to obtain an EDA type resin. This EDA type resin was subjected to Michael addition of acrylonitrile and further reacted with hydroxylamine to obtain a chelate resin having an amidoxime group as a functional group. 10 to 48 meshes of this resin were shaken with sodium aluminate in the same manner as in Example 2. The amount of gallium adsorbed on this resin was 5.7 g/l-R. Comparative Example 2 Of the chelate resins having iminodiacetic acid groups as functional groups obtained by reacting the same chloromethylated resin as in Example 1 with iminodiacetic acid, 10 to 48 meshes of the resin were treated with aluminic acid in the same manner as in Example 2. Shake with sodium. The amount of gallium adsorbed to this resin is
It was 4.3g/l-R. Example 5 A column (inner diameter 25 mm) was filled with 100 ml of the same chelate resin as in Example 1, and the same sodium aluminate aqueous solution as in Example 1 was passed under the same conditions.
The gallium ion concentration and aluminum ion concentration in the effluent that flowed out until the flow rate reached 60 l/l-R was measured. Next, after extruding the sodium aluminate aqueous solution remaining in the column with water, 5 times the resin volume (500 ml) of 3N-HNO ₃ aqueous solution was passed through the column at a flow rate of SV2 in a downward flow. The gallium ion concentration was measured and the elution recovery rate was determined. After washing with water, the same operation as above was repeated, and adsorption-elution tests were conducted three times in total. The results are shown in Table 2. Comparative Example 3 A total of three adsorption-elution tests were conducted under the same conditions as in Example 5, except that the same chelate resin as in Comparative Example 1 was used as the chelate resin. The concentration of metal ions in the effluent and 3N-
Table ₃ shows the results of measuring the elution recovery rate of gallium eluted from the chelate resin by the HNO 3 aqueous solution in each of the three tests.

【table】

【table】

〔Effect of the invention〕

As explained above, the method of the present invention uses a specific resin as a resin base and contains gallium in a chelate resin having at least one of an aminoalkylene phosphate group, an iminoalkylene phosphate group, an alkylene phosphate group, or a salt thereof as a functional group. This is a method of separating gallium by adsorbing it onto a chelate resin by contacting an aqueous aluminate solution with the chelate resin used in the present invention. Since it has superior selectivity and adsorptivity for gallium in an aluminate aqueous solution compared to a resin, according to the method of the present invention, gallium in an aluminate aqueous solution can be selectively separated and recovered at a high recovery rate. In addition, the chelate resin used in the present invention has excellent acid resistance and alkali resistance compared to conventional chelate resins, and there is no risk that the adsorption properties of the chelate resin will decrease due to acids and alkalis.
When recovering the gallium adsorbed to the chelate resin, the chelate resin can be directly treated with strong acid, making it easy to recover the gallium adsorbed to the resin, and the chelate resin after eluting the gallium. It has the advantage of being able to be used repeatedly.

Claims (1)

[Claims] 1. An aqueous aluminate solution containing gallium,
Divinylbenzene copolymer, epoxy resin, phenol resin, resorcinol resin, vinyl chloride resin as a resin base, and at least one of aminoalkylene phosphate groups, iminoalkylene phosphate groups, alkylene phosphate groups, or salts thereof A method for separating gallium in an aqueous aluminate solution, which comprises contacting with a chelate resin having a functional group directly bonded to the resin matrix, and separating gallium by adsorbing it onto the chelate resin. 2. The method for separating gallium in an aqueous aluminate solution according to claim 1, wherein the chelate resin is a porous resin.