JP2670614B2 - Method for removing impure metal ions from zinc plating waste liquid - Google Patents

Description

The present invention relates to a method for cleaning a zinc plating waste liquid by removing impure metal ions such as iron, cobalt, copper and lead in the zinc plating waste liquid.

[Problems to be Solved by the Prior Art and the Invention] A phenol compound having an iminodiacetic acid (or a salt thereof) introduced as a chelate-forming group at the ortho position of the phenol nucleus, and a three-dimensional cross-linking with phenols and aldehydes. The following phenolic chelate resins are known, and these resins are generally used for heavy metal ions: ferric ion> copper ion> nickel ion> aluminum ion> zinc ion> cobalt ion> manganese ion> calcium ion> magnesium ion> barium ion. ≫It is also known to have selective adsorption in the order of sodium ions (JP-A-61-21735).

On the other hand, in recent years, chelate resins have been used to purify and recycle zinc plating waste liquid by removing impure metal ions such as iron ions in the zinc plating waste liquid. A method of adsorbing and removing iron ions (Fe ³⁺ ) in a zinc plating waste liquid by using a phenol-based chelate resin introduced in JP-A-57-27960 is also proposed.

In addition to iron ions, the zinc plating waste liquid may also contain metal ions such as copper ions, cobalt ions, and lead ions, which have a lower concentration than iron ions. However, even if iron ions can be efficiently adsorbed and separated by the above method,
It is difficult to say that even copper ions, cobalt ions, and lead ions can be effectively adsorbed and removed, and in order to further improve the purification level of zinc plating waste liquid, development of a method that can also remove these metal ions is desired. .

[Means for solving the problem]

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that even chelate resins having the same resin matrix and having the same chelate-forming group can selectively adsorb metal ions of the chelate resin finally obtained due to the difference in production method. The results show that the phenols and aldehydes are polycondensed in the presence of aminocarboxylic acids, and the chelating resin having aminocarboxylic acids as functional groups in the zinc plating waste liquid is used as a functional group. The present invention has been completed by finding a method capable of effectively adsorbing and removing not only ions but also impure metal ions other than iron ions to regenerate a zinc plating waste liquid with high purity.

That is, one of the gist of the present invention is to provide a resin having a functional group of aminocarboxylic acids obtained by polycondensing phenols and aldehydes in the presence of aminocarboxylic acids in the presence of an alkaline earth hydroxide. The chelate resin obtained by reacting the unreacted phenols, aldehydes and aminocarboxylic acids remaining in the resin with acid is treated with an acid And an impure metal ion in the zinc plating waste liquid is adsorbed and removed by contacting this resin with a zinc plating waste liquid having a pH of 3 or less. The removal method is.

Another gist of the present invention is that an amino compound obtained by polycondensing a prepolymer obtained by reacting phenols and aldehydes in the presence of aminocarboxylic acids with further addition of phenols and aldehydes. Unreacted phenol remaining in the resin is treated by treating the resin containing carboxylic acids as a functional group with an alkaline earth metal ion aqueous solution in the presence of an alkali hydroxide to adsorb the alkaline earth metal on the resin, and then heating the resin. A chelate resin obtained by reacting a phenol, an aldehyde and an aminocarboxylic acid is treated with an acid to form an acid type resin, and a zinc plating waste liquid having a PH of 3 or less is brought into contact with the resin to impure metal in the waste liquid. A method for removing impure metal ions in a zinc plating waste liquid, characterized by absorbing and removing ions.

Examples of the phenols used for producing the chelate resin used in the present invention include phenol, cresol,
Examples thereof include compounds having a phenolic hydroxyl group such as 3,5-xyler, hydroquinone, resorcin, catechol, β-naphthol, and bisphenol, which may be used alone or in combination of two or more. Aldehydes include, for example, formaldehyde, paraformaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, furfural and the like, and these are used alone or as a mixture of two or more. Examples of aminocarboxylic acids include iminodiacetic acid, iminodipropionic acid, glycine, alanine, lysine, glutamic acid, aspartic acid, sarcosine, valine, leucine, threonine, trocine, and alkali metal salts thereof. Further, acrylates are added to polyalkylene polyamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, metaxylenediamine and polyethyleneimine so that at least one active hydrogen in one molecule remains. A product obtained by saponifying with an acid or an alkali, monochloroacetic acid so that at least one active hydrogen in one molecule remains in a polyalkylene polyamine,
A product obtained by reacting a halogenated carboxylic acid such as monochloropropionic acid or monochlorobutyric acid can also be used as an aminocarboxylic acid. These aminocarboxylic acids can also be used alone or in combination of two or more.

In order to obtain the chelate resin used in the present invention, first, a chelate resin in which an aminocarboxylic acid is introduced into a phenol nucleus of a resin matrix obtained by polycondensing a phenol and an aldehyde is obtained. The reaction of polycondensing phenols and aldehydes is carried out in the presence of iminodicarboxylic acids, and has iminodicarboxylic acids introduced into the phenol nucleus as a functional group, thereby forming a resin matrix in which phenols and aldehydes are polycondensed. General reaction method to obtain the chelating resin with, firstly reacting phenols, aldehydes and aminocarboxylic acids to obtain a prepolymer, then further adding phenols and aldehydes for polycondensation and introducing into the phenol nucleus Having functionalized aminocarboxylic acids as functional groups, Two-step reaction method for obtaining a chelate resin having a resin matrix in which a hydrate such polycondensation can be mentioned. In the above one-step reaction method, phenols, aldehydes,
It is preferable that aminocarboxylic acids are usually charged in a molar ratio of 1: 2 to 6: 1 to 3 and reacted. In this reaction, an alkali metal hydroxide such as potassium hydroxide or sodium hydroxide, an alkaline earth metal salt, or the like can be used as a catalyst. For the reaction, charge phenols, aldehydes, aminocarboxylic acids and catalysts into the reaction vessel,
It is carried out by heating for 30 hours, but it is preferably carried out by adjusting the pH of the reaction system to 7 or more. In the first-step reaction of the two-step reaction method, it is preferable to react phenols, aldehydes and aminocarboxylic acids in a molar ratio of 1: 2 to 5: 1 to 3. In performing the first-stage reaction, an alkali metal hydroxide such as potassium hydroxide or sodium hydroxide, an alkaline earth metal salt, or the like can be used as a catalyst. The first reaction is the reaction of phenols, aldehydes and aminocarboxylic acids in a reaction vessel at 30-100 ° C.
The reaction is carried out by heating for 30 hours, and the pH of the reaction system is preferably adjusted to 7-14. In the two-step reaction method, a prepolymer is synthesized by the first-step reaction, and in the second-step reaction, phenols and aldehydes are further added to the above-mentioned prepolymer to carry out polycondensation of phenols and aldehydes. However, this reaction is based on the number of moles of all phenols (total of phenols into which aminocarboxylic acids are introduced and phenols newly added):
It is preferable to add phenols and aldehydes so that the number of moles of aldehydes becomes 1: 1 to 4.
Number of moles of all phenols: Number of moles of aldehydes is 1: 1
If the amount of aldehydes to the total phenols is too small to be less than the above, curing of the resin does not occur,
There is a risk that only a soft resin will be obtained even if it is cured, and if the amount of aldehydes relative to the total phenols is more than 1: 4, the amount of aldehydes in the resin is large and the odor is long-lasting. There is a risk of elution from inside.
The reaction in the second step is carried out by heating at 30 to 100 ° C. for 1 to 30 hours, and the pH of the reaction system is preferably 7 to 14, especially 8 or more. The above reaction can be carried out by a usual suspension polymerization method.

Unreacted monomers such as phenols, aldehydes and aminocarboxylic acids remain in the resin obtained as described above. Therefore, when the chelate resin used in the present invention is obtained, the aminocarboxylic acid is obtained as described above. After introducing acids into the phenol nucleus as a functional group to form a chelate resin having a resin matrix in which phenols and aldehydes are polycondensed, the resin is treated with an alkaline earth metal ion aqueous solution in the presence of alkali hydroxide. The alkaline earth metal ions are adsorbed on the resin and then heated to react the unreacted monomer remaining in the resin and immobilize it on the resin. This reaction is especially PH = 8.
It is preferable to carry out from 14 to 14. Potassium hydroxide, sodium hydroxide, lithium hydroxide or the like is used as the alkali hydroxide. The alkaline earth metal ions are supplied by adding chlorides, hydroxides or the like of alkaline earth metals such as calcium, magnesium and barium to the above alkaline aqueous solution, but the metal is directly added and dissolved. It may be supplied by When the chelate resin is treated in an alkaline aqueous solution in the presence of alkaline earth metal ions, the adsorption rate of alkaline earth metal ions to the resin is high, and unreacted monomers remaining in the resin in the next heating step are efficiently removed. It can be immobilized on resin. Next, the resin having adsorbed the alkaline earth metal ions is heated, and this heating is preferably performed at 50 to 100 ° C. for 1 to 30 hours. In this way, by adsorbing alkaline earth metal ions on the resin in the alkaline aqueous solution and then heating the resin, the monomers such as phenols, aldehydes and arnocarboxylic acids that have been incorporated into the resin in an unreacted state are removed. While reacting with the resin to be immobilized on the resin, the solvent contained in the resin is distilled off to further cure the resin, and a chelate resin as a final product is obtained.

In the method of the present invention, the above chelate resin (which is Ca type immediately after production) is treated with an acid and used as an acid type resin. For this acid treatment, mineral acids such as hydrochloric acid, sulfuric acid and nitric acid are used, and these acids are preferably used at a concentration of 0.1 to 6N. Next, the acid-type chelate resin is brought into contact with the zinc plating waste liquid, and the zinc plating waste liquid needs to have PH = 3 or less. If the pH of the zinc plating waste liquid exceeds 3, zinc ions are easily adsorbed to the chelating resin, and the adsorption of iron ions, copper ions, cobalt ions, and lead ions to the chelating resin also decreases. It is difficult to effectively adsorb and remove impurity metal ions to separate zinc ions and impurity metal ions. The zinc plating waste liquid PH is preferably 0.5 to 2.5, particularly preferably 1.0 to 2.0.

As a method of bringing the galvanizing waste liquid into contact with the chelate resin, a method of passing the waste liquid through a column filled with the chelate resin is usually adopted, but at this time, the space velocity (SV) of 0.
It is preferable to pass 1 to 10, especially 1 to 5.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Examples 1 to 6 Phenols, aldehydes, aminocarboxylic acids, sodium hydroxide and water were charged into a reaction vessel as shown in Table 1, heated with stirring at 80 ° C for 10 hours, and further heated at 100 ° C for 15 hours.
It was heated for a time to obtain a cured resin. This resin is crushed and washed with water, then added to water in an amount twice the amount of the resin, and a predetermined amount of alkali metal hydroxide shown in Table 1 is added and dissolved with stirring to further dissolve the alkaline earth metal salt. Was added and dissolved, and then heat-treated under reflux of water for 5 hours. After thoroughly washing the obtained chelate resin with water, 2N-HC1 was passed through 4 / -R with SV2, washed with water to form an H-type chelate resin, and a 20-48 mesh chelate resin obtained by sieving this resin was used. The test was conducted under the following conditions.

Example 7 Phenol (1 mol), iminodiacetic acid (2 mol), 37
% Formalin (2.5 mol), sodium hydroxide (2.5 mol) and water (15 mol) were charged and mixed by stirring at room temperature. Then, this mixture was poured into 15 mol of perchlorethylene and suspended to 90 ° C. The mixture was heated to 115 ° C. while distilling off water to complete the addition condensation to obtain a small spherical cured resin. Put the filtered resin into 1.5 times the volume of water of the resin, add sodium hydroxide (3mol) to dissolve, and add calcium chloride (1.5mol) to dissolve, and heat to 95-105 ℃. Then, the solvent remaining in the cured resin was removed by azeotropically distilling water and the solvent. Wash the resin after filtering well with water,
An H-type chelate resin was obtained by neutralizing with hydrochloric acid.
A test was carried out under the following conditions using a chelating resin of 20 to 48 mesh obtained by sieving this resin.

Examples 8 to 13 As shown in Table 2, first, predetermined amounts of phenols, aldehydes, aminocarboxylic acids, sodium hydroxide and water were charged and reacted at 70 ° C for 3 hours to synthesize a prepolymer (first Step reaction), then cool to room temperature, and then add the phenols, aldehydes and water shown in Table 2 and mix well, then heat at 80 ° C. for 10 hours and further 100
It was heated at 0 ° C for 10 hours to obtain a cured resin (second reaction). This resin was crushed and washed with water, then added to twice the amount of water of the resin, dissolved with stirring with the alkali hydroxide shown in Table 2, and the alkaline earth metal shown in the same table was added. And dissolved, and heat-treated under reflux for 5 hours. The obtained chelate resin was thoroughly washed with water and neutralized with hydrochloric acid to obtain an H-type chelate resin. A test was carried out under the following conditions using a chelating resin of 20 to 48 mesh obtained by sieving this resin.

Example 14 The first step reaction was carried out in the same manner as in Example 10 to synthesize a prepolymer, and after cooling to room temperature, phenol (1 mol), 37% formalin (6 mol) and water (20 mol) were added. The mixture was stirred and mixed and suspended in 15 mol of perchlorethylene, and heated to 90 ° C. to distill water.
The temperature was raised to 5 ° C. to complete the addition polymerization, and a small spherical cured resin was obtained. The filtered resin was put into 1.5 times the amount of water of the resin, and sodium hydroxide (3 mol) was added and dissolved, and calcium chloride (1.5 mol) was added and dissolved, and the mixture was heated to 95 to 105 ° C. The solvent remaining in the cured resin was removed by azeotropic distillation with the solvent. The resin after filtration was thoroughly washed with water and neutralized with hydrochloric acid to obtain an H-type chelate resin. A test was conducted using the resin of 20 to 48 mesh obtained by sieving this resin under the following conditions.

Comparative Examples 1-2 (1-oxyphenylene) -2,6-bismethyliminodiacetic acid 125 parts by weight, 37% formalin 26.4 parts by weight, 20% sodium hydroxide 325 parts by weight were charged into a reaction vessel, and 60-65.
The reaction was carried out at 0 ° C for 2 hours. After cooling, 33 parts by weight of phenol was added and the reaction was carried out at 80 to 90 ° C for 3 hours. After cooling the reaction solution, 98 parts by weight of 37% formalin was added and polymerized to obtain a cured resin. After treating this resin with hydrochloric acid to give the acid form,
The test was performed under the conditions shown below using a screen sieved to 20 to 48 mesh.

Test Method A zinc plating solution having the following two compositions was used as a treatment zinc plating solution.

Zinc plating solution A: Zinc (II) ion 101g / Iron (III) ion 1060mg / Lead (II) ion 1.2mg / Copper (II) ion 2.5mg / Cobalt (II) ion 24mg / pH = 1.8 solution Zinc plating solution B: Zinc (II) ion 101g / Iron (II) ion 710mg / Lead (II) ion 0.7mg / Copper (II) ion 7.5mg / Cobalt (II) ion 21mg / pH = 1.5 solution The following tests were conducted using the above zinc plating solution A and zinc plating solution B.

50 ml of each H-type chelate resin obtained in Examples and Comparative Examples was packed in a column (25 mmφ), and the above zinc plating solution at 50 ° C. was passed through SV3 up to 30 / -R to determine the adsorption amount of metal ions. I asked. The results are shown in Table 3. Table 3 also shows the galvanizing solutions A and B used in the test. In Comparative Examples 1 and 2, different plating solutions A and B were treated with the same resin.

[Effects of the Invention] As described above, the method of the present invention, in the presence of aminocarboxylic acids, polycondensates phenols and aldehydes, introduces aminocarboxylic acids into the phenol nucleus as a functional group, and phenols The chelate resin, which constitutes the resin matrix by polycondensing aldehydes with aldehydes, is treated with an alkaline earth metal ion aqueous solution in the presence of alkali hydroxide to adsorb the alkaline earth metal ions on the resin, and then heated. An unreacted phenol, aldehyde, or aminocarboxylic acid remaining in the resin is reacted with an acid-type chelate resin produced by a method of reacting and immobilizing the resin with an acid-type chelate resin. By adopting a method in which the plating waste solution is brought into contact with a pH of 3 or less, iron ions (Fe
³⁺ ) can be adsorbed and removed, as well as cobalt ions, copper ions, lead ions, etc., which have not been the targets of conventional removal, can be adsorbed and removed. Purification can be performed. Further, the method of the present invention has effects such as superior performance of adsorption and removal of impurity metal ions in the zinc plating waste liquid as compared with the conventional method.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masayoshi Masaki 4-66-1 Horikiri Katsushika-ku, Tokyo Miyoshi Yushi Co., Ltd. (56) Reference JP-A-63-130799 (JP, A)

Claims (2)

(57) [Claims] 1. A resin having an aminocarboxylic acid as a functional group, which is obtained by polycondensing phenols and aldehydes in the presence of aminocarboxylic acids, with an alkaline earth metal ion aqueous solution in the presence of alkali hydroxide. The treated chelate resin is treated with an acid to adsorb alkaline earth metal on the resin and then heated to react unreacted phenols, aldehydes and aminocarboxylic acids remaining in the resin with an acid. After making the acid type resin, pH = 3 in this resin
A method for removing impure metal ions in a zinc plating waste liquid, which comprises contacting the following zinc plating waste liquid to adsorb and remove impure metal ions in the waste liquid. 2. A prepolymer obtained by reacting phenols and aldehydes in the presence of aminocarboxylic acids is further added with phenols and aldehydes and polycondensed to give aminocarboxylic acids as a functional group. The resin
Unreacted phenols remaining in the resin after being treated with an alkaline earth metal ion aqueous solution in the presence of alkali hydroxide to adsorb the alkaline earth metal on the resin, and then heated.
A chelate resin obtained by reacting an aldehyde and an aminocarboxylic acid is treated with an acid to form an acid type resin, and a zinc plating waste liquid having a pH of 3 or less is brought into contact with the resin to impure metal ions in the waste liquid. A method for removing impure metal ions in a zinc plating waste liquid, which comprises adsorbing and removing the impurities.