Method for modifying composite nickel protoxide by using sodium salt

Abstract

The invention relates to a method for modifying composite nickel protoxide by using sodium salt, which comprises the following steps: (1) adding iron-containing chloride and nickel chloride solution into a dissolving tank according to the metal proportion corresponding to the product, heating and dissolving to obtain spray pyrolysis pre-solution; the total metal concentration in the liquid before spray pyrolysis is at least maintained at 240 g / L, and the temperature is maintained at 60 DEG C; (2) adding a saturated sodium salt solution into the spray pyrolysis pre-solution, fully and uniformly mixing, and then carrying out spray pyrolysis to obtain a corresponding compound nickel protoxide crude product and a by-product; recovering the by-product for producing a nickel chloride solution; and (3) washing the composite nickel protoxide crude product with hot water, calcining, crushing and then screening to obtain the composite nickel protoxide product. The method is easy to operate, the problem that the apparent density of the composite nickel protoxide product is low is solved, and the character of the composite nickel protoxide is effectively improved. Meanwhile, by-products and waste water generated in the production process can be recycled, and recycling of resources is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy and chemical engineering, and in particular to a method for modifying composite nickelous oxide by using sodium salt. Background Art

[0002] As the demand for nickelous oxide in the battery industry continues to increase, the current bulk density of composite nickelous oxide is relatively low, and after various adjustments, the product performance cannot be effectively improved. In order to ensure the bulk density of composite nickelous oxide, a processing method that does not affect the product formula and electrochemical properties while effectively improving the bulk density of the product is urgently needed. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for modifying composite nickelous oxide by using sodium salt, which is simple to operate and has significant effects.

[0004] In order to solve the above problems, the present invention discloses a method for modifying composite nickelous oxide using sodium salt, comprising the following steps: (1) Putting iron chloride and nickel chloride solution into a dissolving tank according to the metal ratio corresponding to the product and heating and dissolving them to obtain a pre-spray pyrolysis liquid; the total metal concentration in the pre-spray pyrolysis liquid is maintained at at least 240 g / L, and the temperature is maintained at 60°C; (2) adding a saturated sodium salt solution to the liquid before spray pyrolysis, and spray pyrolysis after being fully mixed to obtain a corresponding composite nickelous oxide crude product and by-products; the by-products are recovered and used to produce a nickel chloride solution; ⑶ The crude composite nickelous oxide product is washed with hot water, calcined, crushed, and then sieved through a 100-mesh sieve to obtain a composite nickelous oxide product.

[0005] In the step (1), the iron-containing chloride is replaced by manganese-containing chloride or M-containing chloride; M in the M-containing chloride refers to other metals except iron and manganese.

[0006] The saturated sodium salt solution in step (2) refers to a saturated sodium chloride solution, and the total amount of sodium ions contained in the saturated sodium salt solution accounts for 5 to 50% of the total amount of metals in the liquid before spray pyrolysis.

[0007] The temperature of hot water washing in step (3) is 80-100°C.

[0008] Compared with the prior art, the present invention has the following advantages: 1. The present invention adds an appropriate amount of saturated sodium salt solution to the prepared spray pyrolysis pre-liquid, mixes it thoroughly and evenly, and then sprays pyrolysis is performed, so that the bulk density of the produced product is significantly improved; at the same time, the bulk density of the product is controlled by controlling the proportion of the saturated sodium salt solution added.

[0009] 2. The present invention uses hot water to wash the crude product, and after washing, since sodium chloride and sodium oxide generated in the spraying process are easily soluble in water, there is no sodium residue in the final product, no new impurities are introduced, and the composite nickelous oxide product formula is not affected. In addition, the wastewater containing metal elements such as nickel, manganese, and iron generated in the washing process can be recycled to produce nickel chloride solution without causing metal loss.

[0010] 3. The present invention only needs to add saturated sodium chloride solution to the pre-spray pyrolysis solution in proportion, which is simple to operate and solves the problem of low bulk density of composite nickelous oxide products, effectively improving the properties of composite nickelous oxide. At the same time, by-products and wastewater generated in the production process can be recycled, realizing the recycling of resources. DETAILED DESCRIPTION

[0011] A method for modifying composite nickelous oxide using sodium salt comprises the following steps: ⑴ Put the iron chloride and nickel chloride solution into the dissolving tank according to the metal ratio of the product, heat and dissolve, and obtain the pre-spray pyrolysis liquid. The total metal concentration in the pre-spray pyrolysis liquid is maintained at at least 240g / L to ensure the stability of the spray pyrolysis system; and the temperature is maintained at 60℃ to prevent crystallization due to excessive solution concentration.

[0012] Wherein: iron-containing chloride is replaced by manganese-containing chloride and M-containing chloride; M in M-containing chloride refers to other metals except iron and manganese.

[0013] (2) Add saturated sodium salt solution to the pre-spray pyrolysis solution, which refers to saturated sodium chloride solution, and the total amount of sodium ions contained in the saturated sodium salt solution accounts for 5-50% of the total amount of metal in the pre-spray pyrolysis solution. After being fully mixed and evenly dispersed, spray pyrolysis is performed to obtain the corresponding composite nickelous oxide crude product and by-products; the by-products are recovered and used to produce nickel chloride solution.

[0014] ⑶ The crude composite nickelous oxide product is washed with hot water, calcined, crushed, and then sieved through a 100-mesh sieve to obtain a composite nickelous oxide product.

[0015] The temperature of hot water washing is 80~100℃ to ensure that the washing process is thorough. The wastewater generated during the washing process contains metal elements such as nickel, manganese, and iron, which can also be recycled to produce nickel chloride solution.

[0016] The specific equipment used in the following embodiments is: a 10t / a spray pyrolysis reactor, a pneumatic agitator, a water heater, an electronic scale, a gas storage tank, a compressed air pump and a storage tank, a peristaltic pump, a bag dust collector, an acid mist absorption device, a muffle furnace, a planetary ball mill, and an ultrasonic rotary vibrating screen.

[0017] Taking saturated sodium chloride solution as an example, the solution before spray pyrolysis was prepared and kept warm, and the metal content of the solution was analyzed to ensure that the overall metal content remained above 240g / L.

[0018] Saturated sodium chloride solution with a ratio of 5%, 10%, and 50% of the total amount of metal sodium ions in the liquid before spray pyrolysis was added in a gradient, and the solution was kept at 60°C for spray pyrolysis experiments after being fully mixed. The obtained crude product was washed with 80°C hot water at a water-to-material mass ratio (g / g) of 3:1. After the filtrate was colorless, the product was dried and calcined at 780°C for 2 hours. After the temperature dropped naturally, it was taken out and crushed. After crushing, the material was sieved through a 100-mesh sieve to obtain the final product.

[0019] Example 1 Preparation of composite nickelous oxide-NiFe sample First, a spray pyrolysis pre-liquid with a nickel-iron molar ratio of 2:1 was prepared, and the metal content of nickel-iron in the spray pyrolysis pre-liquid was controlled to be maintained at 240 g / L, and a total of 100 L of solution was prepared.

[0020] Divide it into 4 solutions of 25L each: Solution 1 does not have saturated sodium chloride solution added; Solution 2 adds saturated sodium chloride solution at a sodium content of 5% of the total metal content; Solution 3 adds saturated sodium chloride solution at a sodium content of 10% of the total metal content; Solution 4 adds saturated sodium chloride solution at a sodium content of 50% of the total metal content.

[0021] The above solutions were produced under the same spray pyrolysis conditions, and the crude products were post-treated according to the above method, and then samples were taken to test the bulk density of the products.

[0022] Example 2 Preparation of composite nickelous oxide-NiMn sample First, a spray pyrolysis pre-liquid with a nickel-manganese molar ratio of 2:3 was prepared, and the metal content of nickel and manganese in the spray pyrolysis pre-liquid was controlled to be maintained at 260 g / L, and a total of 100 L of solution was prepared.

[0023] Divide it into 4 solutions of 25L each: Solution 1 does not have saturated sodium chloride solution added; Solution 2 adds saturated sodium chloride solution at a sodium content of 5% of the total metal content; Solution 3 adds saturated sodium chloride solution at a sodium content of 10% of the total metal content; Solution 4 adds saturated sodium chloride solution at a sodium content of 50% of the total metal content.

[0024] The above solutions were produced under the same spray pyrolysis conditions, and the crude products were post-treated according to the above method, and then samples were taken to test the bulk density of the products.

[0025] Samples with different sodium contents were taken under the same spray pyrolysis conditions in Examples 1 and 2, and the relevant data were analyzed and tested. The bulk density was measured while ensuring the product performance, and the bulk density of the products was compared with different gradients. The specific data are shown in Table 1.

[0026] The present invention verifies composite nickelous oxide-NiFe samples and composite nickelous oxide-NiMn samples respectively, and finds that adding sodium chloride can effectively improve the bulk density of the product, indicating that the scheme has wide applicability, but the additive amount needs to be adjusted accordingly for different products.

[0027] Table 1

Claims

1. A method for modifying composite nickelous oxide using sodium salt, comprising the following steps: (1) Putting iron chloride and nickel chloride solution into a dissolving tank according to the metal ratio corresponding to the product and heating and dissolving them to obtain a pre-spray pyrolysis liquid; the total metal concentration in the pre-spray pyrolysis liquid is maintained at at least 240 g / L, and the temperature is maintained at 60°C; (2) adding a saturated sodium salt solution to the liquid before spray pyrolysis, and spray pyrolysis after being fully mixed to obtain a corresponding composite nickelous oxide crude product and by-products; the by-products are recovered and used to produce a nickel chloride solution; ⑶ The crude composite nickelous oxide product is washed with hot water, calcined, crushed, and then sieved through a 100-mesh sieve to obtain a composite nickelous oxide product.

2. The method for modifying composite nickelous oxide using sodium salt as claimed in claim 1, characterized in that: In the step (1), the iron-containing chloride is replaced by manganese-containing chloride or M-containing chloride; M in the M-containing chloride refers to other metals except iron and manganese.

3. The method for modifying composite nickelous oxide using sodium salt as claimed in claim 1, characterized in that: The saturated sodium salt solution in step (2) refers to a saturated sodium chloride solution, and the total amount of sodium ions contained in the saturated sodium salt solution accounts for 5 to 50% of the total amount of metals in the liquid before spray pyrolysis.

4. The method for modifying composite nickelous oxide using sodium salt as claimed in claim 1, characterized in that: The temperature of hot water washing in step (3) is 80-100°C.

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