CN107675199A - The technique that a kind of electrolysis prepares nickel sulfate - Google Patents

Abstract

The invention discloses the technique that a kind of electrolysis prepares nickel sulfate, it is using metal nickel plate as anode material, nickel plate, graphite cake, titanium plate or corronil thin plate are cathode material, and pH=0.5 ~ 5.0, the nickel sulfate solution that nickel ion concentration is 50 ~ 120g/L are as anolyte；Concentration be 0.5 ~ 5mol/L sulfuric acid solutions as catholyte, be 150 ~ 300A/m in current density², 22 ~ 24h of electrolysis under conditions of electrolysis temperature is 25 ~ 100 DEG C.Compared with chemical method, the technique that the present invention prepares nickel sulfate is simple, efficiency high（Electrolyzing rate may be up to 30%）Input cost is low（Ton nickel power consumption can as little as 600Kwh/t）；Nickel sulfate solution nickel ion concentration is more than 110g/L, separates anolyte and catholyte by diaphragm bag by diaphragm bag, anode nickel sulfate solution pH value is maintained at more than 3.0, is advantageous to the direct preparation of nickel sulfate product.

Description

A kind of technique for preparing nickel sulfate by electrolysis

technical field

The invention relates to a method for preparing nickel sulfate, in particular to a process for preparing nickel sulfate by electrolysis, which belongs to the technical field of electrochemistry.

Background technique

Nickel sulfate (NiSO ₄ ), as an important chemical raw material, is widely used in electroplating, batteries, printing and dyeing, medicine, construction, national defense and other fields. There are two methods of preparing nickel sulfate: chemical method and electrochemical method, and the raw materials for producing nickel sulfate include metal nickel plate, high nickel matte, nickel-containing waste materials and crude nickel hydroxide. In the process of preparing nickel sulfate by chemical method, if no co-solvent is added, the dissolution rate of metal nickel plate is only about 10%; and when the co-solvent hydrogen peroxide (H ₂ O ₂ ) is added, the dissolution rate of metal nickel plate The dissolution rate can reach about 20% [Li Dongbo. Research on the direct preparation of refined nickel sulfate from metal nickel plate [D]. Yunnan: Kunming University of Science and Technology, 2011]. Compared with the chemical method, according to Li Daping's research content, it is found that the method of using metal nickel plate to prepare nickel sulfate by electrochemical method has the advantages of high current efficiency, no need to add co-solvent, and simple operation [Li Daping. Preparation of sulfuric acid by electrolysis Nickel process research [J]. Henan Chemical Industry, 1999, 8: 10-12]. However, there is no literature report on the process conditions for the preparation of nickel sulfate solution with high pH value by electrochemical stripping using metal nickel plate as the anode.

Contents of the invention

The object of the present invention is to provide a kind of method for preparing nickel sulfate by electrolysis.

The technique for preparing nickel sulfate by the electrolytic method of the present invention is to take metal nickel plate as anode material, nickel plate, graphite plate, titanium plate or copper-nickel alloy thin plate as cathode material, nickel sulfate solution as anolyte; sulfuric acid solution as catholyte , electrolyze for 22~24h under the condition of current density of 150~300A/m ² and electrolysis temperature of 25~100℃.

The pH of the anolyte nickel sulfate solution is 0.5-5.0, and the concentration of nickel ions is 50-120 g/L.

The concentration of the catholyte sulfuric acid solution is 0.5-5 mol/L.

The liquid level of the anolyte is 1-4 cm higher than that of the catholyte.

The effective area of the cathode material is greater than or equal to the effective area of the anode material; the pole distance is 7-8cm.

After electrolysis, the electrolysis rate of the nickel plate is as high as 30%, and the power consumption per ton of nickel can be as low as 600Kw h/t. Electrolytic method of the present invention prepares the electrode reaction equation of nickel sulfate as follows:

Anode reaction: Ni → Ni ²⁺ + 2e

Anode side reaction: H ₂ O → 2H ⁺ + 1/2O ₂ ↑ + 2e

Cathodic reaction: 2H ⁺ + 2e → H ₂ ↑

Cathode side reaction: Ni ²⁺ + 2e → Ni

Total reaction: Ni + H ₂ SO ₄ = NiSO ₄ + H ₂ ↑

Compared with the chemical method, the process for preparing nickel sulfate in the present invention is simple and efficient (the electrolysis rate of the nickel plate can be as high as 30%). The nickel ion concentration of the nickel sulfate solution is greater than 110g/L, and the input cost is low (the power consumption per ton of nickel can be as low as 600Kw h/t).

In addition, the present invention separates the anolyte and the catholyte through the membrane bag, so that the pH value of the anode nickel sulfate solution is kept above 3.0, which is beneficial to the direct preparation of the nickel sulfate product.

detailed description

The process for preparing nickel sulfate by electrolytic method of the present invention will be further described below through specific examples.

Example 1

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 50g/L at pH=5.0 as the anolyte; prepare a 1mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 2cm higher than the cathode liquid level;

(2) The metal nickel plate is used as the anode material to connect to the positive pole of the power supply; the two nickel plates are used as the cathode material to connect to the negative pole of the power supply. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 50°C, current density 240A/m ² , and electrode spacing 8cm, electrolyze for 24h.

The power consumption per ton of nickel is 1076 Kw h/t; the nickel dissolution rate per 24h is 22%; the pH of the anode solution is 1.5; the concentration of nickel ions in the anode solution is 90g/L.

Example 2

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 50g/L at pH=5.0 as the anolyte; prepare a 1mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 2cm higher than the cathode liquid level;

(2) Use the metal nickel plate as the anode material to connect the positive pole of the power supply; two graphite plates are used as the cathode material to connect the negative pole of the power supply. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 50°C, current density 240A/m ² , and electrode spacing 8cm, electrolyze for 24 hours.

The power consumption per ton of nickel is 1600 Kw h/t; the nickel dissolution rate per 24h is 15%; the pH of the anode solution is 3.3; the concentration of nickel ions in the anode solution is 93g/L.

Example 3

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 50g/L at pH=5.0 as the anolyte; prepare a 1mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 2cm higher than the cathode liquid level;

(2) Connect the positive pole of the power supply with the metal nickel plate as the anode material; connect the negative pole of the power supply with two copper plates as the cathode material. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 50°C, current density 240A/m ² , and electrode spacing 8cm, electrolyze for 24h.

The power consumption per ton of nickel is 1280 Kw h/t; the nickel dissolution rate per 24h is 23%; the pH of the anode solution is 3.2; the concentration of nickel ions in the anode solution is 95g/L.

Example 4

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 50g/L at pH=5.0 as the anolyte; prepare a 1mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 2cm higher than the cathode liquid level;

(2) Connect the positive pole of the power supply with the metal nickel plate as the anode material; connect the negative pole of the power supply with two copper-nickel alloy plates as the cathode material. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 50°C, current density 240A/m ² , and electrode distance 8cm, electrolyze for 24h.

The power consumption per ton of nickel is 964Kw h/t; the nickel dissolution rate per 24h is 27%; the pH of the anode solution is 3.7; the concentration of nickel ions in the anode solution is 108g/L.

Example 5

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 50g/L at pH=5.0 as the anolyte; prepare a 1mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in an electrolytic cell equipped with a heating device, and the anolyte level is kept 1cm higher than the catholyte level;

(2) Connect the positive pole of the power supply with the metal nickel plate as the anode material; connect the negative pole of the power supply with two copper-nickel alloy plates as the cathode material. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 50°C, current density 240A/m ² , and electrode spacing 8cm, electrolyze for 24h.

The power consumption per ton of nickel is 1020Kw h/t; the nickel dissolution rate per 24h is 27%; the pH of the anode solution is 1.0; the concentration of nickel ions in the anode solution is 97g/L.

Example 6

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 120g/L at pH=0.5 as the anolyte; prepare a 5mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 4cm higher than the cathode liquid level;

(2) Connect the positive pole of the power supply with the metal nickel plate as the anode material; connect the negative pole of the power supply with two copper-nickel alloy plates as the cathode material. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 100°C, current density 300A/m ² , and electrode distance 8cm, electrolyze for 24h.

The power consumption per ton of nickel is 1650Kw h/t; the nickel dissolution rate per 24h is 18%; the pH of the anode solution is 4.3; the concentration of nickel ions in the anode solution is 147g/L.

Example 7

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 70g/L at pH=3 as the anolyte; prepare a 1mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 2cm higher than the cathode liquid level;

(2) Connect the positive pole of the power supply with the metal nickel plate as the anode material; connect the negative pole of the power supply with two nickel plates as the cathode material. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the condition of 50℃, 220A/m ² and 8cm electrode distance, the electrolysis was carried out for 24h.

The power consumption per ton of nickel is 735Kw h/t; the nickel dissolution rate per 24h is 28%; the pH of the anode solution is 3.7; the concentration of nickel ions in the anode solution is 127g/L.

Example 8

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 50g/L at pH=5 as the anolyte; prepare a 0.5mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 2cm higher than the cathode liquid level;

(2) Connect the positive pole of the power supply with the metal nickel plate as the anode material; connect the negative pole of the power supply with two nickel plates as the cathode material. The cathode plate and the anode plate have the same area. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 30°C, current density 150A/m ² , and electrode spacing 8cm, it was electrolyzed for 24 hours.

The power consumption per ton of nickel is 1430Kw h/t; the nickel dissolution rate per 24h is 15%; the pH of the anode solution is 3.7; the concentration of nickel ions in the anode solution is 101g/L.

Example 9

(1) Prepare a nickel sulfate solution with a nickel ion concentration of 70g/L at pH=5 as the anolyte; prepare a 1mol/L sulfuric acid solution as the catholyte. The anolyte and catholyte are separated by a diaphragm bag in the electrolytic cell equipped with a heating device, and the anode liquid level is kept 2cm higher than the cathode liquid level;

(2) Connect the positive pole of the power supply with the metal nickel plate as the anode material; connect the negative pole of the power supply with two nickel plates as the cathode material. The area of the cathode plate is 20% larger than that of the anode plate. Each electrode material is directly connected with a DC voltage stabilizing transformer by means of a copper wire. Under the conditions of temperature 50°C, current density 220A/m ² , and electrode spacing 8cm, electrolyze for 24h.

The power consumption per ton of nickel is 600 Kw h/t; the nickel dissolution rate per 24h is 30%; the pH of the anode solution is 3.0; the concentration of nickel ions in the anode solution is 115g/L.

Claims (7)

1. It is nickel plate, graphite cake, titanium plate or copper using metal nickel plate as anode material 1. a kind of electrolysis prepares the technique of nickel sulfate Nickel alloy thin plate is cathode material, and nickel sulfate solution is as anolyte；Sulfuric acid solution is in current density as catholyte 150~300A/m², 22 ~ 24h of electrolysis under conditions of electrolysis temperature is 25 ~ 100 DEG C.
2. 2. the technique that a kind of electrolysis as claimed in claim 1 prepares nickel sulfate, it is characterised in that：Anolyte nickel sulfate is molten Liquid pH=0.5 ~ 5.0, the concentration of nickel ion is 50 ~ 120g/L.
3. 3. the technique that a kind of electrolysis as claimed in claim 1 prepares nickel sulfate, it is characterised in that：Catholyte sulfuric acid solution it is dense Spend for 0.5 ~ 5mol/L.
4. 4. the technique that a kind of electrolysis as claimed in claim 1 prepares nickel sulfate, it is characterised in that：The cathode material it is effective Area is more than or equal to the effective area of anode material.
5. 5. the technique that a kind of electrolysis as claimed in claim 1 prepares nickel sulfate, it is characterised in that：The liquid level of anolyte is higher than the moon Pole 1 ~ 4cm of liquid liquid level.
6. 6. the technique that a kind of electrolysis as claimed in claim 1 prepares nickel sulfate, it is characterised in that：Die opening is 7 ~ 8cm.
7. 7. the technique that a kind of electrolysis as claimed in claim 1 prepares nickel sulfate, it is characterised in that：By diaphragm bag by anolyte Separated with catholyte.