TW201712158A - Device for electrolyzing acidic copper chloride which includes the electrochemical bath and the electroplating bath, without having to use the ionization film for electrolyzing the copper - Google Patents

Abstract

The device for electrolyzing acidic copper chloride according to the present invention includes the electrochemical bath and the electroplating bath; in the electrochemical bath, the ionization film separates the electrochemical bath into the positive-electrode chamber and the negative-electrode chamber, wherein the positive-electrode chamber is configured with a positive-electrode sheet and a negative-electrode chamber is configured with the negative-electrode sheet; the electroplating bath is connected with the negative-electrode chamber via the conduit, and the electrolytic solution in the electroplating bath is pumped into the negative-electrode chamber to reduce the redox potential and then pumped back to the electroplating bath. Circulation of the electrolytic solution in the negative-electrode chamber of the electrochemical bath and the electroplating bath enables the parameter of electrolytic solution to be constantly controlled in the proper ranges, without having to use the ionization film for electrolyzing the copper, in addition, the electroplated copper is adhered onto the outer surface of negative electrode and flattened into a block shape, thus having a higher recycle value.

Description

Electrolytic acid chloride copper device

The invention relates to an electrolytic smelting technology of copper, in particular to a device for electrolytic acidic copper chloride.

Acidic copper chloride is a common etching medium in copper ore smelting and copper recovery in scrap metal. Electrolytic reaction is used to dissolve copper in copper-containing materials such as copper ore and scrap metal in an etching medium to obtain copper. An aqueous solution of acidic copper chloride having a high ion concentration is also referred to as an etchant. In the prior art, copper is electrolytically recovered from an acidic copper chloride etching solution, and the etching liquid is divided into two halves by an ion film. One side is the positive electrode chamber for the positive electrode and the other side is the negative electrode chamber for the negative electrode. The etching solution in the positive electrode chamber causes the oxidation-reduction potential (ORP) of the etching liquid in the positive electrode chamber to become higher and higher due to the oxidation of the positive electrode, and finally, chlorine gas is precipitated. The etching solution in the negative electrode chamber reduces the ORP of the etching solution in the negative electrode chamber due to the reduction of the negative electrode, and finally the negative electrode electrolyzes the metal copper; but the electrolytic copper metal is very rough, usually in a copper powder state, also called Copper mud, deposited at the bottom of the plating bath below the negative electrode, requires further refining to be recycled and used.

The technical problem to be solved by the present invention is to solve the problems in the prior art that the ion plating membrane is used to separate the plating bath, the metal copper obtained by electrolysis is powdered, and the recovery value is not high.

The solution to the above technical problem is to provide an electrolytic acid chlorination The copper device comprises an electrochemical cell and an electroplating cell; in the electrochemical cell, the ion membrane separates the electrochemical cell into a positive electrode chamber and a negative electrode chamber, the positive electrode chamber is provided with a positive electrode sheet, and the negative electrode chamber is provided with a negative electrode sheet; the electroplating pool and the negative electrode chamber Through the pipeline connection, the electrolyte in the plating bath is pumped into the anode chamber, and the oxidation-reduction potential is lowered and pumped back to the plating bath.

In the apparatus for electrolytically using acidic copper chloride provided by the present invention, a staggered positive electrode sheet and a negative electrode sheet are disposed in the plating bath, and copper is deposited on the surface of the negative electrode sheet.

In the apparatus for electrolytic acidic copper chloride provided by the present invention, the electrolyte in the electrochemical cell will increase in oxidation and reduction potential during electrolysis, and will be pumped into the negative electrode chamber when the oxidation-reduction potential of the electrolyte is higher than the threshold, and the negative electrode chamber is lowered. The oxidation-reduction potential of the electrolyte is pumped back to the plating bath.

In the apparatus for electrolytically acidic copper chloride provided by the present invention, the electrolyte in the electrochemical cell and the plating tank flows in a loop to control the oxidation-reduction potential in the electrolyte.

In the apparatus for electrolytically acidic copper chloride provided by the present invention, in the electrochemical cell, the current density of the negative electrode sheet is less than 1 A/dm ² , and the positive electrode chamber is an aqueous sulfuric acid solution.

In order to more clearly illustrate the embodiments of the present invention or the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. It is obvious that the drawings in the following description are only Some of the embodiments of the invention may also be derived from other drawings by those of ordinary skill in the art.

100‧‧‧ plating bath

200‧‧‧ electrolyte

301, 303, 305‧‧‧ positive electrode

302, 304‧‧‧ negative electrode

400‧‧‧Electrical Pool

410‧‧‧ positive room

420‧‧‧Negative chamber

430‧‧‧ positive film

440‧‧‧Negative film

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic view showing the structure of a preferred embodiment of the electrolytic acid copper chloride apparatus of the present invention.

The technology in the embodiment of the present invention will be described below with reference to the accompanying drawings in the embodiments of the present invention. The embodiments are described clearly and completely, and it is obvious that the described embodiments are only a part of the embodiments of the invention, and not all of the embodiments. Many variations and modifications can be derived from the disclosure or teachings herein. If the equivalent changes made in accordance with the teachings of the present invention do not extend beyond the spirit of the specification and the drawings, It is within the technical scope of the present invention.

In the prior art of electrolytically recovering copper from an acidic copper chloride etching solution, an ionic membrane is required to separate the etching liquid into two halves, and various ions in the etching liquid cannot pass through the ion membrane, but the electrons are not blocked, and the electrolysis process is The valence copper ions are reduced at the negative electrode to electrolyze metallic copper. The main innovation of the invention is that the electrolyte membrane is not required to separate the electrolyte, and the positive electrode sheet and the negative electrode sheet are all in the electroplating bath, and the electrolyte is looped in the anode chamber and the electroplating bath of the electrochemical cell, so that the oxidation-reduction potential parameter of the electrolyte is made. The control is always controlled within the appropriate range, and the control of other parameters can be used to accurately control the etching ability and plating ability of the plating bath, so that the metal copper is slowly precipitated from the negative electrode sheet and can be flattened into a block shape.

1 shows the structure of a preferred embodiment of the apparatus for electrolytically acidic copper chloride according to the present invention. As shown in FIG. 1, the apparatus for electrolytically acidic copper chloride includes an electroplating bath 100 and an electrochemical cell 400.

There is no need to provide an ion film in the plating bath 100, and the staggered positive electrode sheets (301, 303, 305) and the negative electrode sheets (302, 304) are immersed in the electrolyte 200, and copper ions are deposited on the surface of the negative electrode sheet along with the reduction of the negative electrode sheet. For example, both sides of the positive electrode 303 are negative electrode sheets (302, 304), and both sides of the negative electrode sheet 302 are positive electrode sheets (301, 303). The number of the positive electrode sheets and the negative electrode sheets can be appropriately adjusted by the size of the plating bath 100 and the copper recovery speed. The more the positive electrode and the negative electrode are, the faster the copper recovery speed is. Of course, when the plating bath 100 is small, a positive electrode sheet and a negative electrode sheet can also realize the plating process of the present invention. Accurate control of erosion of plating bath 100 by controlling parameters in the electrolysis process The ability and plating ability, metal copper slowly precipitated from the surface of the negative electrode sheet and can be flat into a block.

In the electrochemical cell 400 of the present embodiment, the ion membrane divides the electrochemical cell 400 into a positive electrode chamber 410 and a negative electrode chamber 420. The positive electrode chamber 410 is provided with a positive electrode sheet 430, and the negative electrode chamber 420 is provided with a negative electrode sheet 440, a negative electrode chamber 420 and The electroplating bath 100 is the same electrolyte 200, but the oxidation-reduction potential increases as the electrolysis process in the electroplating bath 100 proceeds. When the ORP is too large, the etching ability of the electrolyte 200 is greater than the electroplating ability, so the plating bath 100 The copper cannot be resolved electrically. The electroplating bath 100 and the negative electrode chamber 420 are connected through a pipeline, and the ORP of the electrolytic solution 200 in the electroplating bath 100 is raised and then pumped into the negative electrode chamber 420, and the redox potential is lowered by the reduction action of the negative electrode chamber 420, and then pumped back to the electroplating. Pool 100. The electrolyte 200 is looped in the negative chamber 420 of the electrochemical cell 400 and the plating bath 100 so that the parameters of the electrolyte 200 are always within a suitable range, and the copper can be continuously and electrically analyzed in the plating bath 100. Preferably, the current density of the negative electrode sheet 430 in the electrochemical cell 400 is less than 1 A/dm ² , so that the divalent copper ions Cu ²⁺ in the electrolyte 200 in the negative electrode chamber 420 are reduced to monovalent copper ions Cu ⁺ without being reduced. The metal copper is precipitated from the negative electrode sheet, the amount of divalent copper ions Cu ²⁺ in the electrolyte 200 is reduced, and the ORP is reduced; in the positive electrode chamber 410 of the electrochemical cell 400, an aqueous sulfuric acid solution is used as a conductive medium, for example, a sulfuric acid having a volume fraction of 10%. Aqueous solution.

In the negative electrode chamber 420 and the plating tank 100 of the electrochemical cell 400, the circulating electrolyte 200 is an acidic copper chloride aqueous solution, which is prepared by using an acidic copper chloride etching solution as a mother liquid, usually copper in an acidic copper chloride etching solution. The ion concentration, the chloride ion concentration, and the redox potential (ORP) are relatively high, and the copper recovery process cannot be directly performed as the electrolyte 200. Several conventional parameters of ordinary acidic copper chloride etching solution are listed as follows: copper content: 100g/l~160g/l

Acidity: 1.0N~3.0N

ORP: 430mv~550mv

Chloride ion: 200g/l~280g/l

In the plating bath 100 of the present invention, the parameters of the control electrolyte 200 are: Copper ion concentration: 15g/l~55g/l

Oxidation reduction potential: 250mv~380mv

Negative current density: 3.0A/dm ² ~6.0A/dm ²

Acidity 0.5N~3.0N

Chloride ion concentration is 100g/l~280g/l

Positive electrode current density 2.0A/dm ² ~12.0A/dm ²

In order to more clearly illustrate the working process of the present invention, the process of changing and controlling parameters in the plating bath 100 is explained as follows:

(1) Copper ion concentration: At the beginning, the copper chloride acidic etching solution can be diluted with water to reduce the copper content to the above parameter range. After that, the copper ions are reduced to a copper block by the negative electrode and attached to the negative electrode sheet. The concentration of copper ions is continuously decreased, and an acid etching solution needs to be added to maintain the copper ion concentration in the above parameter range.

(2) Oxidation reduction potential: ORP is the ratio of the divalent copper ion Cu ²⁺ to the monovalent copper ion Cu ^{+ in} the electrolytic solution 200, that is, the more the divalent copper ion Cu ^{2+ in} the electrolytic solution 200, the higher the ORP. In the above-described plating bath 100 used in the present invention, when the ORP is too high, the etching ability of the electrolytic solution 200 is larger than that of the plating, and the negative electrode cannot precipitate copper, so the ORP is lowered by the electrochemical cell 400.

(3) Negative current density: The negative current density during the electrolysis is maintained within the above parameters.

(4) Acidity: During the electrolysis process, the copper ions become copper, releasing the complexed hydrochloric acid, so the acidity will gradually rise and become saturated at 3.0N. But the change in acidity affects the efficiency of copper and the quality of copper. Has little effect.

(5) Chloride ion concentration: Chloride ion has little effect on the electrolysis efficiency and the quality of copper, as long as the chloride ion is not more than 280 g/l. In the case where the etching solution is continuously replenished into the plating bath 100, the chloride ions gradually rise to the same concentration as the chloride ions in the etching solution.

(6) Positive current density: The positive current density has little effect on the electrolysis efficiency and the quality of copper, as long as the current density is not more than 12 A/dm ² .

(7) Stirring: The electrolyte 200 is not stirred during the electrolysis process, and the addition process of the etching solution is smooth and slow, and does not form a stirring effect, so that the outer surface of the negative electrode sheet is coated with a valence copper ion layer and a monovalent copper ion layer. The layer of divalent copper ions is coated on the outside. The composite interlayer state of the monovalent copper ion layer and the divalent copper ion layer can make the metal copper precipitated on the negative electrode sheet more uniform in color, more complete in forming, and smoother in surface.

In the present invention, the electrolyte 200 is looped in the anode chamber 420 of the electrochemical cell 400 and the plating bath 100, so that the oxidation-reduction potential of the electrolyte 200 is always controlled within a suitable range, in order to more clearly illustrate the redox of the electrolyte 200. The control process of the potential can adopt a plurality of loops of the electrolyte 200, and can be roughly divided into a discontinuous loop and a continuous loop. For example, the intermittent loop is usually the highest ORP setting of the electrolyte 200 in the plating bath 100. The threshold value, as the electrolysis process of the electrolyte 200 proceeds, the ORP will rise. When the oxidation-reduction potential of the electrolyte 200 is higher than the highest threshold, the electroplating bath 100 stops working, pumping the electrolyte 200 into the negative chamber 420, and the anode chamber 420 is lowered. When the ORP of the electrolyte 200 reaches a suitable range, it is pumped back to the plating bath 100, and the plating bath 100 is turned on to continue the copper recovery process. The continuous loop can stop the electroplating bath 100, but flow the electrolyte 200 in the electrochemical cell 400 and the electroplating bath 100, and pump the electrolyte 200 in the electroplating bath 100 into the electrochemical cell 400 at a certain rate. The electrolyte 200 in the electrochemical cell 400 is pumped into the plating bath at a certain rate. 100, it is only necessary to maintain the redox potential of the electrolyte 200 in the plating bath 100 within a suitable parameter range.

The invention has the following beneficial effects: the electrolyte is looped in the negative electrode chamber and the electroplating bath of the electrochemical cell, so that the parameter control of the electrolyte is always controlled within a suitable range, and the copper can be electrolyzed without using an ion membrane, and the electrolysis The copper is attached to the outer surface of the negative electrode and is flattened into a block shape, which has a high recovery value.

100‧‧‧ plating bath

200‧‧‧ electrolyte

301, 303, 305‧‧‧ positive electrode

302, 304‧‧‧ negative electrode

400‧‧‧Electrical Pool

410‧‧‧ positive room

420‧‧‧Negative chamber

430‧‧‧ positive film

440‧‧‧Negative film

Claims (5)

An apparatus for electrolyzing acidic copper chloride includes an electrochemical cell and an electroplating cell; in the electrochemical cell, an ion membrane divides the electrochemical cell into a positive electrode chamber and a negative electrode chamber, and at least one of the positive electrode chambers is disposed The positive electrode sheet is provided with at least one negative electrode plate in the negative electrode chamber; the plating bath is connected to the negative electrode chamber through a pipe, and the electrolyte in the plating bath is pumped into the negative electrode chamber, and the oxidation-reduction potential is lowered and pumped back to the plating bath. . The apparatus for electrolytically storing acidic copper chloride according to claim 1, wherein the plating bath is provided with staggered positive electrode sheets and negative electrode sheets, and copper is deposited on the surface of the negative electrode sheets. The apparatus for electrolytically acidic copper chloride according to claim 1, wherein the electrolyte in the electrochemical cell increases the oxidation-reduction potential during electrolysis, and is pumped when the oxidation-reduction potential of the electrolyte is higher than a threshold. The anode chamber is lowered, and the anode chamber is pumped back to the plating bath after lowering the oxidation-reduction potential of the electrolyte. The apparatus for electrolytically acidic copper chloride according to claim 1, wherein the electrochemical cell and the electrolyte in the plating tank flow to control the oxidation-reduction potential in the electrolyte. The apparatus for electrolytically acidic copper chloride according to claim 1, wherein in the electrochemical cell, the current density of the negative electrode sheet is less than 1 A/dm ² , and the positive electrode chamber is an aqueous sulfuric acid solution.