A purification device and purification method for hydrochloric acid type trivalent chromium electroplating solution

Abstract

A purification device and purification method for hydrochloric acid type trivalent chromium electroplating solution, the purification device includes: a main plating tank, a filtering device and a resin tank; the main plating tank is connected to the filtering device through a first connecting pipe; the filtering device is connected to the resin tank through a second connecting pipe; the resin tank is connected to the main plating tank through a third connecting pipe; the second connecting pipe is connected to the main plating tank through a fourth connecting pipe; the first connecting pipe is provided with a first valve body at the output end of the main plating tank; the second connecting pipe is provided with a third valve body at the input end of the resin tank; the third connecting pipe is provided with a sixth valve body; the fourth connecting pipe is provided with a fourth valve body. The purification method includes: a single filtering mode, a single purification mode and a purification and filtering mode. The purification device can realize the switching between the single filtering mode, the single purification mode and the purification and filtering mode by adjusting the connection state between the main plating tank, the filtering device and the resin tank, thereby improving the purification efficiency of the hydrochloric acid type trivalent chromium electroplating solution.

Description

Technical Field

[0001] The invention relates to the technical field of metal purification, and in particular to a purification device and a purification method for a hydrochloric acid type trivalent chromium electroplating solution. Background Art

[0002] The trivalent chromium plating solution is highly acidic (pH is about 2.6). During production, due to the dissolution of dropped parts and incomplete washing, the trivalent chromium plating solution is easily contaminated by some heavy metal impurities, such as copper, zinc, iron, nickel, etc. The content of these metal impurities needs to be strictly controlled, for example, copper impurities are required to be <10ppm; generally, if the impurities exceed a certain range, it is easy to cause production failures, so the trivalent chromium process maintenance requirements are high, and the plating solution must be purified regularly. At the same time, trivalent chromium electroplating does not contain hexavalent chromium and does not require the addition of fluorinated chromium defogging agents. It is an environmentally friendly electroplating technology and is widely used in the export processing of electronic products. At present, the methods for purifying trivalent chromium plating solutions are: small current electrolysis method, decontamination water method and dilution plating solution method. For the small current electrolysis method, it is necessary to configure an auxiliary tank and an electrolysis device, and the electrolysis plate needs to be replaced frequently. Long-term electrolysis will consume a large amount of stabilizer, resulting in high production costs and low efficiency. For the method of adding impurity-removing water, although the impurity removal effect is good and fast, long-term use will lead to the accumulation of impurity-removing masking agents, resulting in deterioration of plating solution performance. For the diluted plating solution method, the trivalent chromium plating solution has a high specific gravity and the inorganic salt content is close to 500g / L. Direct discharge of the diluted plating solution will cause a large amount of raw material waste and cause pollution to the environment. Summary of the invention

[0003] The object of the present invention is to provide a purification device for hydrochloric acid type trivalent chromium electroplating solution, which has the function of simply switching between a single filtering mode, a single purification mode and a purification and filtering mode.

[0004] The present invention also provides a purification method, which uses the above-mentioned purification device to purify the hydrochloric acid type trivalent chromium electroplating solution through a single filtering mode, a single purification mode and a purification and filtering mode.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A purification device for hydrochloric acid type trivalent chromium electroplating solution, comprising: a main plating tank, a filtering device and a resin tank;

[0007] The main plating tank is connected to the filter device through a first connecting pipe; the filter device is connected to the resin tank through a second connecting pipe; the resin tank is connected to the main plating tank through a third connecting pipe; the second connecting pipe is connected to the main plating tank through a fourth connecting pipe;

[0008] The first connecting pipe is provided with a first valve body at the output end of the main plating tank; the second connecting pipe is provided with a third valve body at the input end of the resin tank; the third connecting pipe is provided with a sixth valve body; and the fourth connecting pipe is provided with a fourth valve body.

[0009] Preferably, it also includes: a regenerator;

[0010] The regenerator is connected to the first connecting pipe through a fifth connecting pipe; the fifth connecting pipe is provided with a second valve body;

[0011] The input end of the sixth connecting pipe is communicated with the third connecting pipe and is provided with a fifth valve body.

[0012] Preferably, the main plating tank comprises: a trivalent chromium plating tank and an overflow tank;

[0013] The trivalent chromium plating tank and the overflow tank are connected; the first connecting pipe is connected to the overflow tank;

[0014] The third connecting pipe and the fourth connecting pipe are connected to the trivalent chromium plating tank.

[0015] Preferably, the trivalent chromium plating tank and the overflow tank are arranged close to each other, and the two are connected by a through hole.

[0016] Preferably, the regenerator is provided with a sulfuric acid output device and an ammonia water output device;

[0017] The sulfuric acid output device is used to output sulfuric acid to the fifth connecting pipe;

[0018] The ammonia water output device is used to output ammonia water to the fifth connecting pipe.

[0019] Preferably, the second valve body and / or the fifth valve body is a solenoid valve.

[0020] Preferably, at least one of the first valve body, the third valve body, the fourth valve body and the sixth valve body is a solenoid valve.

[0021] A purification method comprises the following steps:

[0022] Single filtration mode: open the first valve body and the fourth valve body, and close the other valve bodies; the hydrochloric acid type trivalent chromium plating solution output from the main plating tank enters the filtration device through the first connecting pipe, and then returns to the main plating tank through the second connecting pipe and the fourth connecting pipe;

[0023] Single purification mode: open the first valve body, the third valve body and the sixth valve body, and close the other valve bodies; the hydrochloric acid type trivalent chromium plating solution output from the main plating tank enters the filter device through the first connecting pipe, enters the resin tank from the second connecting pipe, and then returns to the main plating tank from the third connecting pipe;

[0024] Purification and filtration mode: open the first valve body, the third valve body, the fourth valve body and the sixth valve body, and close the other valve bodies; after the hydrochloric acid type trivalent chromium electroplating solution output from the main plating tank enters the filtering device through the first connecting pipe, part of the hydrochloric acid type trivalent chromium electroplating solution returns to the main plating tank through the second connecting pipe and the fourth connecting pipe, and the other part of the hydrochloric acid type trivalent chromium electroplating solution enters the resin tank from the second connecting pipe, and then returns to the main plating tank through the third connecting pipe.

[0025] Preferably, it also includes: resin regeneration mode: open the second valve body, the third valve body and the fifth valve body, and close the other valve bodies; the regeneration liquid output from the regenerator enters the filter device through the fifth connecting pipe and the first connecting pipe, and enters the resin tank from the second connecting pipe, and is output to the outside of the purification device from the third connecting pipe and the sixth connecting pipe.

[0026] Beneficial effects of the present invention:

[0027] The purification device can switch between a single filtering mode, a single purification mode and a purification-while-filtering mode by adjusting the connection state between the main plating tank, the filtering device and the resin tank, thereby improving the purification efficiency of the hydrochloric acid type trivalent chromium electroplating solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the purification device.

[0029] in:

[0030] Main plating tank 01, filtering device 02, resin tank 03, regenerator 04;

[0031] Trivalent chromium plating tank 11, overflow tank 12;

[0032] A first connecting pipe 21, a second connecting pipe 22, a third connecting pipe 23, a fourth connecting pipe 24, a fifth connecting pipe 25, and a sixth connecting pipe 26;

[0033] The first valve body 31 , the second valve body 32 , the third valve body 33 , the fourth valve body 34 , the fifth valve body 35 , and the sixth valve body 36 . DETAILED DESCRIPTION

[0034] The technical solution of the present invention is further described below through specific implementation modes in conjunction with the accompanying drawings.

[0035] A purification device for hydrochloric acid type trivalent chromium electroplating solution, comprising: a main plating tank 01, a filtering device 02 and a resin tank 03;

[0036] The main plating tank 01 is connected to the filter device 02 through a first connecting pipe 21; the filter device 02 is connected to the resin tank 03 through a second connecting pipe 22; the resin tank 03 is connected to the main plating tank 01 through a third connecting pipe 23; the second connecting pipe 22 is connected to the main plating tank 01 through a fourth connecting pipe 24;

[0037] The first connecting pipe 21 is provided with a first valve body 31 at the output end of the main plating tank 01; the second connecting pipe 22 is provided with a third valve body 33 at the input end of the resin tank 03; the third connecting pipe 23 is provided with a sixth valve body 36; the fourth connecting pipe 24 is provided with a fourth valve body 34.

[0038] The purification device can switch between a single filtering mode, a single purification mode and a purification-while-filtering mode by adjusting the connection state between the main plating tank 01, the filtering device 02 and the resin tank 03, thereby improving the purification efficiency of the hydrochloric acid type trivalent chromium electroplating solution.

[0039] The main plating tank 01 is filled with hydrochloric acid type trivalent chromium plating solution. The trivalent chromium plating solution is highly acidic (pH about 2.6). Due to the dissolution of dropped parts and incomplete water washing during production, the trivalent chromium plating solution is easily contaminated by some heavy metal impurities, such as copper, zinc, iron, nickel, etc. The content of these metal impurities needs to be strictly controlled, for example, copper impurities are required to be <10ppm; generally, if the impurities exceed a specific range, it is easy to cause production failures. Therefore, the trivalent chromium process maintenance requirements are relatively high, and the plating solution must be purified regularly.

[0040] Specifically, the purification device has at least three modes: a single filtering mode, a single purification mode, and a purification-and-filtering mode;

[0041] The single filtering mode is that the purification device only performs filtering operation; in the single filtering mode, the first valve body 31 and the fourth valve body 34 are opened, and the other valve bodies are closed; the trivalent chromium plating solution output from the main plating tank 01 passes through the first valve body 31 and the fourth valve body 34, and then passes through the filtering device 02, and the filtering device 02 filters the mixed solution of the trivalent chromium plating solution to separate the solids that are insoluble in the trivalent chromium plating solution, and remove impurities from the trivalent chromium plating solution. The filtered trivalent chromium plating solution returns to the main plating tank 01; under the continuous and repeated reflux of the trivalent chromium plating, the impurities in the trivalent chromium plating solution will eventually settle in the filtering device 02.

[0042] The single purification mode is a purification mode, which uses the resin in the resin tank 03 to selectively adsorb the metal impurity ions in the trivalent chromium plating solution. When the trivalent chromium plating solution flows through the resin tank 03, the resin adsorbs the metal impurity ions in the trivalent chromium plating solution, thereby achieving the purpose of purifying the trivalent chromium plating solution. In the single purification mode, the first valve body 31, the third valve body 33 and the sixth valve body 36 are opened, and the other valve bodies are closed. The trivalent chromium plating solution passes through the first valve body 31, the third valve body 33 and the sixth valve body 36, and then passes through the filter device 02 and the resin tank 03. It is first filtered to prevent excessive impurities from being injected into the resin tank 03, and then enters the resin tank 03 for purification. The resin tank 03 can be filled with ion exchange resin, which can purify the trivalent chromium plating solution when it contacts the trivalent chromium plating solution.

[0043] The purification and filtering mode is to perform filtering and purification operations at the same time; in this mode, the first valve body 31, the third valve body 33, the fourth valve body 34 and the sixth valve body 36 are opened, and after the trivalent chromium plating solution passes through the filter, part of the trivalent chromium plating solution enters from the fourth connecting pipe 24 and flows back to the main plating tank 01, and the other part will enter the resin tank 03 for purification and flow back to the main plating tank 01, which can realize continuous operation without stopping operation and has high purification efficiency.

[0044] At the same time, this solution can set conventional devices in the purification device, such as pumps, flow meters or barometers; the pump can be set at any position between the first connecting pipe to the sixth connecting pipe to pump the trivalent chromium plating solution to the main plating tank, thereby increasing the flow rate of the trivalent chromium plating solution.

[0045] Preferably, it also includes: a regenerator 04;

[0046] The regenerator 04 is connected to the first connecting pipe 21 through a fifth connecting pipe 25; the fifth connecting pipe 25 is provided with a second valve body 32;

[0047] The input end of the sixth connecting pipe 26 is connected to the third connecting pipe 23 and is provided with a fifth valve body 35 .

[0048] The purification device also has a regeneration mode. In the regeneration mode, the second valve body 32, the third valve body 33 and the fifth valve body 35 are opened, and the other valve bodies are closed; the regenerator 04 outputs the regeneration solution, and the regeneration solution is output to the outside of the purification device after passing through the fifth connecting pipe 25, the first connecting pipe 21, the filter, the second connecting pipe 22, the resin tank 03, the third connecting pipe 23 and the sixth connecting pipe 26 to rinse the filter layer located in the filter and regenerate the resin in the resin tank 03 to restore the purification capacity of the resin tank 03.

[0049] Preferably, the main plating tank 01 comprises: a trivalent chromium plating tank 11 and an overflow tank 12;

[0050] The trivalent chromium plating tank 11 and the overflow tank 12 are connected; the first connecting pipe 21 is connected to the overflow tank 12;

[0051] The third connecting pipe 23 and the fourth connecting pipe 24 are connected to the trivalent chromium plating tank 11 .

[0052] The trivalent chromium plating tank 11 is filled with a trivalent chromium plating solution, and is used to collect and output the trivalent chromium plating solution. When the trivalent chromium plating solution needs to be output, the trivalent chromium plating solution only needs to be output to the overflow tank 12, and then output to the first connecting pipe 21 by the overflow tank 12. The overflow tank 12 has the function of removing the gas in the main plating tank 01, and also has the function of storing mixed gas and metal impurities, thereby increasing the storage capacity of the main plating tank 01.

[0053] Preferably, the trivalent chromium plating tank 11 and the overflow tank 12 are arranged close to each other, and are connected by a through hole.

[0054] The trivalent chromium plating tank 11 and the overflow tank 12 can be connected by conventional connection methods, such as pipe connection, etc. Preferably, the trivalent chromium plating tank 11 and the overflow tank 12 can be arranged close to each other, and a through hole is opened between the two on the same wall surface. The trivalent chromium plating solution flows only through the through hole, so that large impurities in the trivalent chromium plating tank 11 can be confined to the trivalent chromium plating tank 11 and will not enter the overflow tank 12, thereby preventing impurities from entering various pipelines to block the pipelines and affect the purification process.

[0055] Preferably, the regenerator 04 is provided with a sulfuric acid output device and an ammonia water output device;

[0056] The sulfuric acid output device is used to output sulfuric acid to the fifth connecting pipe 25;

[0057] The ammonia water output device is used to output ammonia water to the fifth connecting pipe 25 .

[0058] The sulfuric acid output device is used to output sulfuric acid solution, which is an acidic reagent; the ammonia water output device is used to output ammonia water solution, which is an alkaline reagent; this scheme selects two different acid and alkaline reagents as the regeneration solution of the regenerator 04, which can promote the regeneration ability of the resin tank 03 to restore the purification function of the resin tank 03.

[0059] Preferably, the second valve body 32 and / or the fifth valve body 35 is a solenoid valve.

[0060] Preferably, at least one of the first valve body 31 , the third valve body 33 , the fourth valve body 34 and the sixth valve body 36 is a solenoid valve.

[0061] The first to sixth valve bodies can preferably be solenoid valves, which can be remotely controlled to be opened and closed by a worker's one-button start during the purification process, making it easier to adjust various modes of the purification device.

[0062] A purification method comprises the following steps:

[0063] Single filtration mode: open the first valve body 31 and the fourth valve body 34, and close the other valve bodies; the hydrochloric acid type trivalent chromium electroplating solution output from the main plating tank 01 enters the filtering device 02 through the first connecting pipe 21, and then returns to the main plating tank 01 through the second connecting pipe 22 and the fourth connecting pipe 24;

[0064] Single purification mode: open the first valve body 31, the third valve body 33 and the sixth valve body 36, and close the other valve bodies; the hydrochloric acid type trivalent chromium electroplating solution output from the main plating tank 01 enters the filter device 02 through the first connecting pipe 21, enters the resin tank 03 from the second connecting pipe 22, and then returns to the main plating tank 01 through the third connecting pipe 23;

[0065] Purification and filtration mode: open the first valve body 31, the third valve body 33, the fourth valve body 34 and the sixth valve body 36, and close the other valve bodies; after the hydrochloric acid type trivalent chromium electroplating solution output from the main plating tank 01 enters the filtering device 02 through the first connecting pipe 21, part of the hydrochloric acid type trivalent chromium electroplating solution returns to the main plating tank 01 through the second connecting pipe 22 and the fourth connecting pipe 24, and the other part of the hydrochloric acid type trivalent chromium electroplating solution enters the resin tank 03 from the second connecting pipe 22, and then returns to the main plating tank 01 through the third connecting pipe 23.

[0066] Preferably, it also includes: resin regeneration mode: open the second valve body 32, the third valve body 33 and the fifth valve body 35, and close the other valve bodies; the regeneration liquid output from the regenerator 04 enters the filter device 02 through the fifth connecting pipe 25 and the first connecting pipe 21, and enters the resin tank 03 from the second connecting pipe 22, and is then output to the outside of the purification device from the third connecting pipe 23 and the sixth connecting pipe 26.

[0067] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the scope of protection of the present invention.

Claims

1. Application of a purification device in purifying hydrochloric acid type trivalent chromium electroplating solution, characterized in that: include: Main plating tank, filtration unit and resin tank; The main plating tank is connected to the filter device through a first connecting pipe; the filter device is connected to the resin tank through a second connecting pipe; the resin tank is connected to the main plating tank through a third connecting pipe; the second connecting pipe is connected to the main plating tank through a fourth connecting pipe; The first connecting pipe is provided with a first valve body at the output end of the main plating tank; the second connecting pipe is provided with a third valve body at the input end of the resin tank; the third connecting pipe is provided with a sixth valve body; the fourth connecting pipe is provided with a fourth valve body; The purification method of the purification device comprises the following steps: Single filtration mode: open the first valve body and the fourth valve body, and close the other valve bodies; the hydrochloric acid type trivalent chromium plating solution output from the main plating tank enters the filtration device through the first connecting pipe, and then returns to the main plating tank through the second connecting pipe and the fourth connecting pipe; Single purification mode: open the first valve body, the third valve body and the sixth valve body, and close the other valve bodies; the hydrochloric acid type trivalent chromium plating solution output from the main plating tank enters the filter device through the first connecting pipe, enters the resin tank from the second connecting pipe, and then returns to the main plating tank from the third connecting pipe; Purification and filtration mode: open the first valve body, the third valve body, the fourth valve body and the sixth valve body, and close the other valve bodies; after the hydrochloric acid type trivalent chromium electroplating solution output from the main plating tank enters the filtering device through the first connecting pipe, part of the hydrochloric acid type trivalent chromium electroplating solution returns to the main plating tank through the second connecting pipe and the fourth connecting pipe, and the other part of the hydrochloric acid type trivalent chromium electroplating solution enters the resin tank from the second connecting pipe, and then returns to the main plating tank through the third connecting pipe.

2. The use of a purification device according to claim 1 in purifying a hydrochloric acid type trivalent chromium electroplating solution, characterized in that: Also includes: Regenerator; The regenerator is connected to the first connecting pipe through a fifth connecting pipe; the fifth connecting pipe is provided with a second valve body; The input end of the sixth connecting pipe is communicated with the third connecting pipe and is provided with a fifth valve body.

3. The use of a purification device according to claim 2 in purifying a hydrochloric acid type trivalent chromium electroplating solution, characterized in that: The main plating tank comprises: a trivalent chromium plating tank and an overflow tank; The trivalent chromium plating tank and the overflow tank are connected; the first connecting pipe is connected to the overflow tank; The third connecting pipe and the fourth connecting pipe are connected to the trivalent chromium plating tank.

4. The use of a purification device according to claim 3 in purifying a hydrochloric acid type trivalent chromium electroplating solution, characterized in that: The trivalent chromium plating tank and the overflow tank are arranged close to each other, and the two are connected by a through hole.

5. The use of a purification device according to claim 2 in purifying a hydrochloric acid type trivalent chromium electroplating solution, characterized in that: The regenerator is provided with a sulfuric acid output device and an ammonia water output device; The sulfuric acid output device is used to output sulfuric acid to the fifth connecting pipe; The ammonia water output device is used to output ammonia water to the fifth connecting pipe.

6. The use of a purification device according to claim 2 in purifying a hydrochloric acid type trivalent chromium electroplating solution, characterized in that: The second valve body and / or the fifth valve body is a solenoid valve.

7. Use of a purification device according to any one of claims 1 to 6 in purifying a hydrochloric acid type trivalent chromium electroplating solution, characterized in that: At least one of the first valve body, the third valve body, the fourth valve body and the sixth valve body is a solenoid valve.

8. Use of a purification device according to any one of claims 1 to 6 in purifying a hydrochloric acid type trivalent chromium electroplating solution, characterized in that: The purification method also includes: a resin regeneration mode: opening the second valve body, the third valve body and the fifth valve body, and closing the remaining valve bodies; the regeneration liquid output from the regenerator enters the filtering device through the fifth connecting pipe and the first connecting pipe, and enters the resin tank from the second connecting pipe, and is then output to the outside of the purification device from the third connecting pipe and the sixth connecting pipe.

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