Activation method of nickel electrolysis anode slime

Abstract

The invention relates to an activation method of nickel electrolysis anode slime, which comprises the following steps: adding nickel electrolysis anode slime into alkaline water, reacting at 50-70 DEG C, cooling to room temperature after the pH value of slurrying liquid is neutral, and carrying out solid-liquid separation to obtain active nickel electrolysis anode slime. By means of the method, the hydrophilic performance of the anode mud is improved, the hydrophilic proportion of the anode mud is increased to 100% from 15%, an anion layer composed of S2-and SO3 < 2-> is generated on the surface of the anode mud, and the anode mud has certain copper removal capacity. When the activated anode slime is matched with nickel concentrate for use, the copper removal effect can be remarkably enhanced, and the copper removal rate is increased to 99.95% from 15%. In addition, the activation method is green and environment-friendly, the filtrate separated after activation can be continuously used for preparing alkaline water, no wastewater is generated in the activation process, and the green production requirement is met.

Description

Technical Field

[0001] The invention relates to the technical field of nickel electrolyte purification, and in particular to an activation method for nickel electrolytic anode mud. Background Art

[0002] Electrolytic nickel not only has excellent electrical conductivity, thermal conductivity and plasticity, but also has high strength and high corrosion resistance. It is an indispensable raw material in many industrial fields. Copper is one of the key impurities in nickel electrolyte. Its presence will significantly reduce the purity of electrolytic nickel and affect the physical properties and chemical stability of the product. At present, the copper removal method of nickel concentrate plus anode mud is generally used in the nickel electrolysis production process. After the copper removal operation, the copper content of the copper-containing nickel solution is reduced from 0.7-1.0g / L to less than 0.002g / L. At the same time, in the process of copper removal, the nickel in the nickel concentrate will be transferred to the solution to compensate for the nickel loss of the nickel electrolyte. It is an economical and efficient copper removal method. However, after anode mud is left for a long time, it is easy to lose water. Since the main component of anode mud is sulfur, which has hydrophobic properties, it is easy to float on the surface of the liquid to be purified, resulting in a significant deterioration in the copper removal effect, which in turn causes fluctuations in the composition of the purified solution. In order to obtain a better copper removal effect, a large amount of anode mud needs to be invested and the purification time is extended, which increases the amount of copper removal slag and nickel loss. When treating waste slag, it is easy to cause a large amount of sulfur source loss, resource waste and increased purification costs. In addition, the extension of purification time and the instability of copper removal purification make the purification system unable to meet the needs of electrolysis / electroplating liquid, resulting in a decline in product quality and production capacity, which seriously affects the sustainable development of the enterprise. Therefore, it is of great significance to design and develop a method to improve the hydrophilicity of anode mud for a long time, so as to improve its copper removal effect when combined with nickel concentrate. Summary of the invention

[0003] In view of the problem in the above-mentioned prior art that the copper removal effect of the anode mud in combination with nickel concentrate deteriorates after being left for a long time, the present invention provides a method for activating the anode mud of nickel electrolysis, which effectively improves the hydrophilicity of the anode mud and thereby enhances the copper removal effect of the anode mud in combination with nickel concentrate.

[0004] To achieve the above object, the technical solution of the present invention is as follows:

[0005] A method for activating nickel electrolytic anode mud comprises the following steps:

[0006] Add nickel electrolytic anode mud into alkaline water, react at 50-70°C, wait until the pH value of the slurry is neutral, cool to room temperature, separate the solid and liquid, and obtain active nickel electrolytic anode mud.

[0007] Furthermore, the alkaline water is prepared from one or more of sodium hydroxide, potassium hydroxide, calcium oxide, magnesium oxide, sodium carbonate, and sodium bicarbonate, and the alkaline water is a dilute solution with a pH of 12-14.

[0008] Furthermore, the solid-to-liquid ratio of the nickel electrolysis anode mud to the alkaline water is 1:3-20.

[0009] Furthermore, the nickel electrolysis anode mud is in the form of loose particles, and its main component includes sulfur, and the sulfur content is greater than 97%.

[0010] The present invention also relates to a method for purifying a copper-nickel solution using activated nickel electrolysis anode mud, comprising the following steps:

[0011] activation:

[0012] Add nickel electrolytic anode mud into alkaline water, react at 50-70°C, wait until the pH value of the slurry is neutral, cool to room temperature, separate the solid and liquid, and obtain active nickel electrolytic anode mud.

[0013] Copper removal reaction:

[0014] (1) heating the copper-nickel solution to 50-70° C.;

[0015] A certain proportion of active nickel electrolytic anode mud and nickel concentrate are added to the heated copper-nickel solution, reacted at a constant temperature for 20-60 minutes, filtered, and a copper-removed solution is obtained.

[0016] Furthermore, the copper-nickel solution includes a copper-nickel mixed acid solution, a copper-nickel sulfate solution, and a copper-nickel electroplating solution.

[0017] Furthermore, the copper-nickel mixed acid solution includes nickel sulfate and nickel chloride.

[0018] Furthermore, the mass ratio of the active nickel electrolysis anode mud to the nickel concentrate is 1:2-5, and the mass ratio of the active nickel electrolysis anode mud to the copper in the copper-containing nickel solution is 1:1-2.

[0019] The reaction principle involved in the present invention is as follows:

[0020] The activation principle of nickel electrolysis anode mud is:

[0021]

[0022] The principle of nickel concentrate-anode mud copper removal is Ni2S3+2Cu 2+ =2Ni 2+ +2CuS↓+S↓ and Ni+S+Cu 2+ =Ni 2+ +CuS↓ amplified as:

[0023] Cu 2+ +S 2- =CuS↓

[0024] Cu 2+ +Sx 2- =CuS x ↓

[0025] 2Cu 2+ +SO3 2- +H2O=2Cu + +SO4 2- +2H +

[0026] 2Cu 2+ +S2O3 2- +H2O=2Cu + +SO4 2- +2H + +S↓

[0027] 2Cu + +S 2- =Cu2S↓

[0028] 2Cu + +S x 2- =Cu2S x ↓

[0029] According to the above reaction, the nickel electrolysis anode mud is activated and forms a surface composed of S 2- and SO3 2- The anion layer composed of S 2- and SO3 2- The presence of can improve the copper removal capacity of nickel electrolysis anode mud itself. Therefore, when nickel electrolysis anode mud is combined with nickel concentrate, the copper removal effect of nickel concentrate-anode mud can be significantly improved.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention provides a method for activating nickel electrolytic anode mud. First, the nickel electrolytic anode mud is activated by using a disproportionation reaction of sulfur and alkali, which not only improves the hydrophilicity of the anode mud, increasing its hydrophilicity from 15% to 100%, but also forms a S-containing ion on the surface of the anode mud. 2- and SO3 2- The anion layer composed of activated anode mud itself has a certain copper removal ability. When the activated anode mud is used in combination with nickel concentrate, the copper removal effect can be significantly enhanced, and the copper removal rate is increased from 15% to 99.95%. In addition, the activation method is green and environmentally friendly. The filtrate separated after activation can continue to be used for the preparation of alkaline water. No wastewater is generated during the activation process, meeting the requirements of green production. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The embodiments of the present invention are further described below with reference to the accompanying drawings, in which:

[0033] Figure 1 The flowchart of the long-standing anode mud activation and copper removal operation from nickel concentrate is shown. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0035] A method for purifying a copper-nickel solution using activated nickel electrolytic anode mud comprises the following steps:

[0036] activation:

[0037] Add nickel electrolytic anode mud into alkaline water, react at 50-70°C, wait until the pH value of the slurry is neutral, cool to room temperature, separate the solid and liquid, and obtain active nickel electrolytic anode mud.

[0038] Copper removal reaction:

[0039] (1) heating the copper-nickel solution to 50-70° C.;

[0040] (2) Add a certain proportion of active nickel electrolytic anode mud and nickel concentrate to the heated copper-nickel solution, react at a constant temperature for 20-60 minutes, filter, and obtain a copper-removed solution.

[0041] Example 1

[0042] A method for purifying a copper-nickel solution using activated nickel electrolytic anode mud comprises the following steps:

[0043] activation:

[0044] 5 g of nickel electrolytic anode mud was added into 100 mL of magnesium oxide alkaline water with pH = 12, and reacted at 70°C until the pH value of the slurry was neutral. The mixture was then cooled to room temperature, solid-liquid separated, and the active nickel electrolytic anode mud was dried for later use.

[0045] Copper removal reaction:

[0046] (1) heating 1 L of copper-containing nickel sulfate solution to 60° C., wherein the copper-containing nickel sulfate solution contains 70 g / L nickel and 0.5 g / L copper;

[0047] (2) Add 0.5 g of active nickel electrolytic anode mud and 1 g of nickel concentrate to the heated copper-containing nickel sulfate solution, react at a constant temperature for 60 min, filter, and obtain a copper-removed solution.

[0048] The copper removal solution was analyzed by ICP-AES, and the copper content in the copper removal solution was found to be 0.35 g / L, and the copper removal rate was 30%.

[0049] Example 2

[0050] A method for purifying a copper-nickel solution using activated nickel electrolytic anode mud comprises the following steps:

[0051] activation:

[0052] 5 g of nickel electrolytic anode mud was added into 100 mL of potassium hydroxide alkaline water with pH = 14, and reacted at 50°C until the pH value of the slurry was neutral. Then, the mixture was cooled to room temperature, the solid and liquid were separated, and the active nickel electrolytic anode mud was dried for later use.

[0053] Copper removal reaction:

[0054] (1) heating 1 L of copper-containing nickel sulfate solution to 50° C., wherein the copper-containing nickel sulfate solution contains 70 g / L nickel and 0.5 g / L copper;

[0055] (2) Add 0.5 g of active nickel electrolytic anode mud and 1 g of nickel concentrate to the heated copper-containing nickel sulfate solution, react at a constant temperature for 30 min, filter, and obtain a copper-removed solution.

[0056] The copper removal solution was analyzed by ICP-AES, and the copper content in the copper removal solution was found to be 0.0005 g / L, and the copper removal rate was 99.9%.

[0057] Example 3

[0058] A method for purifying a copper-nickel solution using activated nickel electrolytic anode mud comprises the following steps:

[0059] activation:

[0060] 5 g of nickel electrolytic anode mud was added into 100 mL of sodium carbonate alkaline water with pH = 14, and reacted at 60° C. until the pH value of the slurry was neutral. The mixture was then cooled to room temperature, solid-liquid separated, and the active nickel electrolytic anode mud was dried for later use.

[0061] Copper removal reaction:

[0062] (1) heating 1 L of copper-nickel mixed acid solution to 60° C., wherein the copper-nickel sulfate solution contains 68 g / L nickel and 0.65 g / L copper;

[0063] (2) Add 0.65 g of active nickel electrolytic anode mud and 3.25 g of nickel concentrate to the heated copper-nickel mixed acid solution, react at a constant temperature for 20 min, filter, and obtain a copper-removed solution.

[0064] The copper removal solution was analyzed by ICP-AES, and the copper content in the copper removal solution was found to be 0.0003 g / L, and the copper removal rate was 99.95%.

[0065] Example 4

[0066] A method for purifying a copper-nickel solution using activated nickel electrolytic anode mud comprises the following steps:

[0067] activation:

[0068] 5 g of nickel electrolytic anode mud was added into 100 mL of sodium hydroxide alkaline water with pH = 14, and reacted at 70°C until the pH value of the slurry was neutral. The mixture was then cooled to room temperature, solid-liquid separated, and the active nickel electrolytic anode mud was dried for later use.

[0069] Copper removal reaction:

[0070] (1) heating 1L of copper-containing nickel electroplating solution to 70° C., wherein the copper-containing nickel sulfate solution contains 50 g / L nickel and 1.0 g / L copper;

[0071] (2) Add 0.5 g of active nickel electrolytic anode mud and 1.5 g of nickel concentrate to the heated copper-containing nickel electroplating solution, react at a constant temperature for 60 min, filter, and obtain a copper-removed solution.

[0072] The copper removal solution was analyzed by ICP-AES, and the copper content in the copper removal solution was found to be 0.005 g / L, and the copper removal rate was 99.5%.

[0073] Comparative Example 1

[0074] Copper removal reaction:

[0075] (1) heating 1 L of a copper-nickel mixed acid solution to 60° C., wherein the copper-nickel mixed acid solution contains 68 g / L nickel and 0.65 g / L copper;

[0076] (2) Add 0.65 g of long-standing nickel electrolysis anode mud and 3.25 g of nickel concentrate to the heated copper-nickel mixed acid solution, react at a constant temperature for 20 min, filter, and obtain a copper-removed solution.

[0077] The copper removal solution was analyzed by ICP-AES, and the copper content in the copper removal solution was found to be 0.55 g / L, and the copper removal rate was 15%.

[0078] The present invention provides a method for activating nickel electrolytic anode mud. First, the nickel electrolytic anode mud is activated by using a disproportionation reaction of sulfur and alkali, which not only improves the hydrophilicity of the anode mud, increasing its hydrophilicity from 15% to 100%, but also generates a hydrophilic layer composed of S on the surface of the anode mud. 2- and SO3 2-The anion layer composed of activated anode mud itself has a certain copper removal ability. When the activated anode mud is used in combination with nickel concentrate, the copper removal effect can be significantly enhanced, and the copper removal rate is increased from 15% to 99.95%. In addition, the activation method is green and environmentally friendly. The filtrate separated after activation can continue to be used for the preparation of alkaline water. No wastewater is generated during the activation process, meeting the requirements of green production.

[0079] Some exemplary embodiments of the present invention are described above. It can be understood that the above embodiments are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention. The features in these embodiments can be recombined in a suitable manner, and the scheme obtained thereby is still within the protection scope required by the present invention. Based on the above embodiments, all other embodiments obtained by those skilled in the art without making creative work, that is, all modifications, equivalent substitutions and improvements made within the spirit and principles of this application, fall within the protection scope required by the present invention.

Claims

1. A method for activating nickel electrolytic anode mud, characterized in that: The following steps are involved: Add nickel electrolytic anode mud into alkaline water, react at 50-70°C, wait until the pH value of the slurry is neutral, cool to room temperature, separate the solid and liquid, and obtain active nickel electrolytic anode mud.

2. The method for activating nickel electrolytic anode mud according to claim 1, characterized in that: The alkaline water is prepared from one or more of sodium hydroxide, potassium hydroxide, calcium oxide, magnesium oxide, sodium carbonate and sodium bicarbonate, and the alkaline water is a dilute solution with a pH of 12-14.

3. The method for activating nickel electrolytic anode mud according to claim 1, characterized in that: The solid-to-liquid ratio of the nickel electrolysis anode mud to the alkaline water is 1:3-20.

4. The method for activating nickel electrolytic anode mud according to claim 1, characterized in that: The nickel electrolysis anode mud is in the form of loose particles, and its main component includes sulfur, and the sulfur content is greater than 97%.

5. A method for purifying a copper-nickel solution using activated nickel electrolytic anode mud, characterized in that: The following steps are involved: activation: Add nickel electrolytic anode mud into alkaline water, react at 50-70°C, wait until the pH value of the slurry is neutral, cool to room temperature, separate the solid and liquid, and obtain active nickel electrolytic anode mud. Copper removal reaction: (1) heating the copper-nickel solution to 50-70° C.; (2) Add a certain proportion of active nickel electrolytic anode mud and nickel concentrate to the heated copper-nickel solution, react at a constant temperature for 20-60 minutes, filter, and obtain a copper-removed solution.

6. The method for purifying a copper-nickel solution using activated nickel electrolysis anode mud according to claim 5, characterized in that: The copper-nickel solution includes a copper-nickel mixed acid solution, a copper-nickel sulfate solution, and a copper-nickel electroplating solution.

7. The method for purifying a copper-nickel solution using activated nickel electrolysis anode mud according to claim 6, characterized in that: The copper-nickel mixed acid solution comprises nickel sulfate and nickel chloride.

8. A method for purifying a copper-nickel solution using activated nickel electrolysis anode mud according to any one of claims 5 to 7, characterized in that: The mass ratio of the active nickel electrolysis anode mud to the nickel concentrate is 1:2-5, and the mass ratio of the active nickel electrolysis anode mud to the copper in the copper-containing nickel solution is 1:1-2.

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