JP4538801B2 - Method for recovering Ni from deoxidation solution - Google Patents

Description

  The present invention relates to a copper electrolyte cleaning solution. More specifically, the present invention can be obtained in a step of simultaneously removing Ni and As from a Ni, As-containing electrolyte in copper electrolysis using a deoxidized resin and a de-As resin. The present invention relates to a method for recovering Ni from a deoxidized solution.

There are various methods in the process of removing impurities from the copper electrolyte, generally referred to as the liquid purification process. After removing copper, As, Sb, Bi, etc. by electrolysis, sulfurization, solvent extraction, precipitation, etc. After removing the impurities, Ni is crystallized in the form of Ni sulfate.
For example, as shown in Fig. 1, the copper electrolyte is subjected to copper removal electrolysis, As, Sb and Bi are removed, Ni is crystallized, and crude sulfuric acid Ni is recovered. The recovered liquid is sent to the copper electrolysis process. It is done.

For crystallization of Ni, a submerged combustion method, a freezing method, a neutralization method, or the like is employed.
In the submerged combustion method disclosed in Japanese Patent Application Laid-Open No. 2003-222408 (Patent Document 1) or the like, the liquid to be treated is concentrated by submerged combustion, the solubility of Ni is lowered by increasing the sulfuric acid concentration, and Ni is crystallized by the difference in solubility. The freezing method is a method in which the temperature of the liquid to be treated is lowered and Ni is crystallized by the difference in solubility.

On the other hand, regarding deoxidation of electrolyte solution, JP2004-169158 (Patent Document 2), Michael Sheedy
“ACID RECOVERY AND PURIFICATION USING ABSORPTION RESIN TECHNOLOGY” (Non-patent Document 2) etc. are used to reduce the neutralization cost when removing Ni. Is about 80%, and an acid loss of about 20% occurs.
In order to increase the purity of the Ni recovered product, it is necessary to reduce the concentration of impurities such as As, Sb and Bi in advance.

For example, in the method of removing As, Sb, Bi, etc. from the electrolytic solution by electrolysis, copper and As, Sb, Bi are deposited at the same time, so that the obtained electrodeposit does not become a product and is repeated in the smelting process. Become.
The submerged combustion method and the freezing method, in which Ni is recovered with Ni sulfate from the post-electrolysis solution, are Ni recovery methods using a difference in solubility, so that the concentration rate increases when the sulfuric acid concentration of the liquid to be treated is high. Cannot be effectively removed Ni.

JP-A-2003-222408 Submerged combustion apparatus Patent application title: Method for purifying copper electrolyte Michael Sheedy “ACID RECOVERYAND PURIFICATION USING ABSORPTION RESIN TECHNOLOGY”

The present invention proposes an efficient and low-cost processing method by increasing the concentration rate of the electrolytic solution and improving the Ni recovery efficiency in the liquid purification process in copper electrolysis.

That is, the present invention

(1) In the copper electrolyte solution cleaning step, desulfurization and debi from the electrolyte are performed with a chelate resin having an aminophosphate group,
The Ni-containing low-concentration acid solution in which As, Sb, Bi, and sulfuric acid are adsorbed and removed by passing the solution after de-Sb and de-Bi in series with a strongly basic anion exchange resin and a chelate resin having a glucamine group ( (Hereinafter referred to as “deoxidation liquid”) and this deoxidation liquid is concentrated in the existing concentration step to obtain a high concentration deoxidation liquid (hereinafter referred to as “concentration liquid”), and the solubility in the submerged combustion method and the freezing method. A method for recovering Ni from a deoxidation solution that efficiently recovers Ni sulfate by increasing the difference.

(2) A method of recovering Ni from a deoxidized solution in which Ni sulfate is recovered by a submerged combustion method or a refrigeration method after sulfiding the concentrated liquid in (1) above to remove impurities other than Ni as sulfides.
It is.

According to the present invention,
(1) Since As, Sb, Bi in the copper electrolyte can be separated and removed from copper, the generation amount of copper and As, Sb.Bi compounds can be reduced, so that the return of the valuable material to the smelting process can be avoided. .
(2) The thin sulfuric acid solution generated during deoxidation of the ion exchange resin can be reused as the eluent of the de-As resin.

(3) The solubility difference in the Ni crystallization process (de-Ni process) can be increased, the de-Ni efficiency can be improved, and the post-de-Ni solution can be repeated in the copper electrolysis process.
(4) Moreover, this invention can reduce a sulfuric acid loss.

The copper electrolyte solution cleaning flow using the present invention is shown in FIG.
The solution to be treated of the present invention is a copper electrolyte.
The total sulfuric acid concentration in the copper electrolyte is 250 to 280 g / L, the inner free sulfuric acid is 160 to 180 g / L, the copper is 45 to 55 g / L, the Sb is 0.2 to 0.5 g / L, As is 3.5 to 5.5 g / L, Bi is 0.15 to 0.35 g / L, Ni is 10 to 14 g / L, Fe is 0.3 to 0.5 g / L, Ca is 0.38 to 0.45 g / L.

In the present invention, first, Sb removal and Bi removal are performed.
De-Sb and De-Bi are simultaneously performed with a chelate resin having an aminophosphate group. For example, S950 (manufactured by PUROLITE Co., Ltd.) is used as the resin.
The treatment solution (electrolytic solution) is SV (value indicating how many times the amount of the resin has been passed in 1 hour, representing the flow rate) with respect to the resin. About 70 to 90).

Next, the solution after de-Sb-de-Bi is passed through de-acid and de-As resin.
The deoxidizing resin tower and the de-As resin tower are connected in series, and the liquid after Sd and Bi removal and water are alternately passed.
For example, PA316 (manufactured by Mitsubishi Chemical Corporation) is used as the deoxidizing resin.
For example, CRB02 (manufactured by Mitsubishi Chemical Corporation) is used as the de-As resin.
Further, the treatment liquid is passed through the resin by SV3 to 5 and BV2 to 4 or so.

By this operation, it is separated and recovered into a) a deoxidizing solution having a low acid concentration and an As concentration, b) a recovered acid having a high acid concentration, and c) an As eluent having a low acid concentration, copper concentration and Ni concentration and containing As. It becomes possible.
The separation between the deacidified solution and the recovered acid is determined by how many times the current concentration rate is concentrated.

In other words, when trying to concentrate twice the current concentration rate, the recovery of the deacid solution is stopped when the sulfuric acid concentration in the cumulative recovery solution from the start of recovery of the deacid solution is half of the current concentration of sulfuric acid. Then, it switches to recovery of recovered acid.

The existing Ni recovery equipment can be used as it is for recovering Ni from the deoxidation solution. As described above, since the concentration rate can be increased more than the current state, the Ni solubility difference before and after the Ni sulfate crystallization can be made larger than the current state, and efficient Ni recovery can be performed.

If the amount of impurities removed from the pre-Ni crystallization solution is insufficient only by removing As, Sb, Bi by the above method, the concentrated solution before Ni crystallization is sulfidized, and Cu, As, Sb, Bi is sulfided. It is also possible to remove as.

Since As, Sb, Bi can be removed from the copper electrolyte by this method, the copper concentration in the copper removal electrolyte for maintaining the copper balance of copper electrolysis can be kept high. Production will be possible with quality that can be sold outside the whole quantity.

The electrolyte solution was de-Sb de-Bi with a chelate resin having an aminophosphate group.
The liquid after the above treatment was connected in series with a resin tower filled with deoxidized resin PA316 7L and a resin tower filled with de-As resin CRB02 7L, and at a flow rate of 420 cc / min, electrolytic solution 50 minutes, water 50 minutes Were alternately passed and processed. The results are shown in Tables 1 and 2.

A deoxidized solution having an acid concentration of 67 g / L, copper concentration of 34 g / L, Ni concentration of 9 g / L, As concentration of 0.8 g / L, Sb concentration of 0.03 g / L, and Bi concentration of 0.07 g / L can be recovered. .

The ratio of Ni / acid in a normal electrolyte is 10.9 / 158.7 = 0.069, whereas the ratio of Ni / acid in a deoxidizer is 9/67 = 0.134. For example, when the acid concentration is concentrated to 300 g / L, the Ni concentration in deoxidizing solution is 41.8 g / L with respect to the normal electrolytic solution Ni concentration of 20.6 g / L, and ΔNi during Ni crystallization can be increased. I understand.

FIG. 3 shows the result of crystallization of Ni from the deoxidized solution recovered by the same method as described above.
Volatilizes and concentrates 20L of deoxidized solution with acid concentration 74g / L, copper concentration 34g / L, Ni concentration 8g / L, As concentration 0.77g / L, Sb concentration 0.025g / L, Bi concentration 0.022g / L 10L.
After removing the copper sulfate crystallized during the concentration process, the solution was electrolessly electrolyzed to recover metallic copper, and the Cu concentration of the solution was lowered.

This liquid was further volatile concentrated to 5 L of half (concentrated 4 times from the raw material deoxidized liquid).
The concentrated liquid is cooled and the concentrated liquid obtained by crystallizing and removing copper as copper sulfate is separately added to a hydrogen sulfide gas generated by adding a sodium hydrosulfide solution to sulfuric acid. -The silver chloride electrode reference) was reached and Cu and As were completely removed from the solution as sulfides.

A small amount of deoxidizing solution was added to the sulfurized solution to remove hydrogen sulfide in the solution, and then cooled to −15 ° C. to crystallize crude Ni sulfate.
The deoxidizing solution used as the raw material for this treatment had an original Ni / acid ratio of 8 / 74.1 = 0.108, which was slightly inferior to the separation results of Example 1 above, but was still concentrated to concentrate Ni crystals. ΔNi at the time of analysis was treated with an ordinary electrolytic solution (usually ΔNi: 12 g / L × 2 times-14.8 g / L = 9.2 g / L, Example 2: 31.27 g / L-14.8 g / L = 16.47 g / L).

Table 3 Example 2 shows the quality of the finally obtained Ni sulfate.
On the other hand, a comparative example of the quality of crude sulfuric acid Ni recovered by sulfidation and freezing from a solution obtained by concentrating a normal electrolyte solution twice is shown in Comparative Example of Table 3 in comparison with the present invention.
The quality of the Ni sulfate recovered in the present invention was the same or better than that of the recovered product according to the prior art and As, Sb, Bi, Cu, Ca, etc. except for Fe.

The conventional Ni collection | recovery method is shown. The impurity removal flow sheet using the chelate resin which is 1 aspect of this invention is shown. The flow sheet of the recovery method of the sulfuric acid Ni from the deoxidation liquid which is 1 aspect of this invention is shown.

Claims (2)

In the copper electrolyte solution purification process, desulfurization and debi from the electrolyte are performed with a chelate resin having an aminophosphate group,
The Ni-containing low-concentration acid solution in which As, Sb, Bi, and sulfuric acid are adsorbed and removed by passing the solution after de-Sb and de-Bi in series with a strongly basic anion exchange resin and a chelate resin having a glucamine group ( (Hereinafter referred to as “deoxidation liquid”) and this deoxidation liquid is concentrated in the existing concentration step to obtain a high concentration deoxidation liquid (hereinafter referred to as “concentration liquid”), and the solubility in the submerged combustion method and the freezing method. A method for recovering Ni from a deoxidizing solution, characterized by efficiently recovering Ni sulfate by increasing the difference. A method for recovering Ni from a deoxidized solution, wherein the concentrated solution according to claim 1 is subjected to a sulfidation treatment to remove impurities other than Ni as sulfides, and thereafter Ni sulfate is recovered by a submerged combustion method or a refrigeration method.