JPH03252318A - Production of nickel hydroxide - Google Patents

Abstract

PURPOSE:To improve the controllability of particle size distribution by intermittently increasing the amount of an aqueous solution of an alkali metal hydroxide over a prescribed period to control the pH of the reaction system, thereby forming fine particles of Ni(OH)2 acting as nuclei. CONSTITUTION:An aqueous solution of an Ni salt having a concentration of 0.5-3.5mol/l or an aqueous solution produced by adding 0.01-5mol/l of a Co salt and 0.01-5mol/l of a Cd salt to the above solution is continuously supplied to a reactor 1 through a feed line 3. The reactor is further supplied with 1.21-10mol/l aqueous solution of an alkali metal hydroxide through a feed line 7 and 3-7.5mol/l of an ammonium ion source through a feed line 5. The mixed solution is made to react by maintaining the temperature to 20-80 deg.C and pH to 9-12. After the reaction, the pH of the system is quickly raised by intermittently increasing the feeding rate of the aqueous solution of alkali metal hydroxide and is maintained in the state for a prescribed period to form fine particles of Ni(OH)2. Thereafter the feeding amount of the aqueous solution of alkali metal hydroxide is returned to the normal level to proceed the reaction. The formed fine particles of Ni(OH)2 are delivered through a delivery line 15.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a novel method for producing spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium.

In the following, unless otherwise specified, "nickel hydroxide particles or powder" includes "nickel hydroxide particles or powder containing cobalt and cadmium."

Prior art and its problems Nickel hydroxide powder used in non-sintered nickel positive electrodes for alkaline batteries is required to have a spherical particle shape and a high bulk density.

This is because (a) when such nickel hydroxide powder is used as an active material for a nickel positive electrode and is filled into a metallic pocket, it can be densely packed, and (b) when it is mixed with a conductive agent as an active material. When used in paste form, the properties of the paste such as fluidity are stabilized, so filling properties, filling rate, etc. are improved. (C) Therefore, (B), (
In both cases of b), the utilization rate of the active material is improved and an electrode with excellent performance can be obtained.

However, in conventional methods for producing nickel hydroxide, it has been difficult to obtain powder with the above characteristics.

One of the inventors of this application, as a result of intensive research in view of the current state of technology, found that [(a) nickel salt aqueous solution, (b)
In producing nickel hydroxide by reacting an aqueous alkali metal hydroxide solution and (c) an ammonium ion donor, the above three (a), (b) and (c) are reacted simultaneously and consecutively. the temperature of the reaction system from 20 to 80°C.
The reaction is allowed to proceed while maintaining the pH at a constant value in the range of 9 to 12 to produce spherical nickel hydroxide particles with an average particle size of 2 to 50 μm, which are continuously taken out. The applicant has completed a patent application for the "method for producing di-soquel hydroxide characterized by its characteristics" (Japanese Patent Application Laid-open No. 2-6340; hereinafter, this method will be referred to as the prior invention).
.

Although this prior invention is an excellent method compared to the prior art described above, as the nickel hydroxide particles grow overall as the reaction progresses, the number of microparticles becomes insufficient. Therefore, when filling a metallic pocket or the like as an active material of a nickel positive electrode, the product tends to have a large porosity, that is, a bulky product with a tapping density. An increase in tapping density leads to a decrease in the utilization rate as a positive electrode for an alkaline battery, so improvement in this point is desired.

Means for Solving the Problems As a result of further research in view of the current state of the technology as described above, the present inventor has discovered that nickel hydroxide can be hydrated to a desired particle size in the continuous production process of nickel hydroxide according to the prior invention. When the pH of the reaction system is periodically varied or the supply of ammonium ion donor is stopped or reduced when the growth of nickel particles has progressed, microparticles that become the core of nickel hydroxide particles are added to the reaction system. is formed, and by returning the pH of the reaction system to its initial value, a cycle consisting of particle growth and generation of particle nuclei is repeated, and as a result, nickel hydroxide with a stable tapping density is obtained. I found out that it can be done.

In addition, by repeating the cycle consisting of particle growth and generation of particle nuclei in the same manner as above under different conditions in multiple reaction systems, and then mixing the obtained particle groups with different particle sizes, a predetermined It has also been found that mixed nickel hydroxide particles with a more precisely controlled particle size distribution can be easily obtained.

That is, the present invention provides the following method for producing nickel hydroxide: (a) nickel salt aqueous solution or an aqueous solution containing nickel salt, cobalt salt and cadmium salt, (b) alkali metal hydroxide aqueous solution and (iii) ammonium ion donor is continuously supplied to the reaction system, and the temperature of the reaction system is maintained at 20 to 8
Proceeding the reaction while maintaining the pH at a constant value within the range of 0 ° C. and at a constant value within the range of 9 to 12 to generate nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium, and generate nickel hydroxide particles containing cobalt and cadmium. In a method of continuously taking out a substance, the pH of the reaction system is adjusted by increasing the amount of alkali metal hydroxide aqueous solution supplied intermittently over a certain period of time, thereby generating fine nickel hydroxide particles that serve as the nucleus. A method for producing spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium, characterized by:

■ Continuously supply (a) a nickel salt aqueous solution or an aqueous solution containing a nickel salt, cobalt salt, and cadmium salt, (b) an alkali metal hydroxide aqueous solution, and (c) an ammonium ion donor to the reaction system. Temperature 20-8
Proceeding the reaction while maintaining the pH at a constant value within the range of 0'C and at a constant value within the range of 9 to 12 to generate nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium, and In a method of continuously taking out a substance, fine particles of nickel hydroxide, which serve as cores, are generated by stopping the supply of ammonium ion donor to the reaction system intermittently for a certain period of time, or reducing the supply amount. A method for producing spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium, characterized by:

■ Continuously supply (a) a nickel salt aqueous solution or an aqueous solution containing a nickel salt, cobalt salt, and cadmium salt, (b) an alkali metal hydroxide aqueous solution, and (c) an ammonium ion donor to the reaction system. Temperature 20-8
Proceeding the reaction while maintaining the pH at a constant value within the range of 0 ° C. and at a constant value within the range of 9 to 12 to generate nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium, and generate nickel hydroxide particles containing cobalt and cadmium. In a method for continuously extracting substances, reactions are carried out under different conditions in multiple reaction systems to form particle groups with different particle sizes, and an aqueous alkali metal hydroxide solution is intermittently added to each reaction system over a certain period of time. By increasing the supply amount of nickel hydroxide and adjusting the pH of the reaction system, nickel hydroxide fine particles that serve as the core are generated,
Spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium characterized in that mixed particles having a predetermined particle size distribution are obtained by mixing the particle groups with different particle sizes obtained above. manufacturing method.

■ Continuously supply (a) a nickel salt aqueous solution or an aqueous solution containing a nickel salt, cobalt salt, and cadmium salt, (b) an alkali metal hydroxide aqueous solution, and (c) an ammonium ion donor to the reaction system. Temperature 20-8
The reaction is allowed to proceed while maintaining a constant value within the range of 0°C and the pH within the range of 9 to 12 to produce nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium, and the product is continuously In this method, reactions are carried out under different conditions in multiple reaction systems to form particle groups with different particle sizes, and in each reaction system, an ammonium ion donor is intermittently supplied to the reaction system for a certain period of time. By stopping the supply of nickel hydroxide or reducing its supply amount, fine nickel hydroxide particles are generated as a core, and by mixing the particle groups with different particle sizes obtained above, a predetermined particle size distribution is obtained. A method for producing spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium, the method comprising obtaining mixed particles.

In the following, the invention set forth in claim 1 of the present application will be referred to as the first invention of the present application, the invention set forth in claim 2 of the present application will be referred to as the second invention of the present application, and the invention set forth in claim 2 of the present application will be referred to as the third invention of the present application.
The invention set forth in claim 1 is the third invention of the present application, and the invention set forth in claim 4 of the present application is the fourth invention of the present application. In addition, unless there is a particular distinction between each invention, the invention as a whole will simply be referred to as the present invention.

Examples of the salt forming the (a) nickel salt aqueous solution used in the method of the present invention include water-soluble nickel salts such as nickel nitrate, nickel sulfate, and nickel chloride. The concentration of the nickel salt aqueous solution is usually 0. 5-3.5 mol/Q
That's about it. When containing cobalt salts and cadmium salts together with nickel salts in an aqueous solution, water-soluble cobalt salts such as cobalt sulfate, cobalt nitrate, and cobalt chloride, and water-soluble cadmium salts such as cadmium sulfate, cadmium nitrate, and cadmium chloride are used. be done.

The concentration of cobalt in an aqueous solution is as cobalt ion,
The concentration of cadmium is about 0.01 to 0.5 mol/Q, and the concentration of cadmium is about 0.01 to 0.5 mol/Q as cadmium ions.

Examples of the alkali metal hydroxide aqueous solution used in the method of the present invention include aqueous solutions of sodium hydroxide, potassium hydroxide, and the like. The concentration of the aqueous alkali metal hydroxide solution is usually about 1.25 to 10 mol/Q.

(iii) The ammonium ion donor used in the present invention is an aqueous solution of ammonium salt such as ammonium nitrate, ammonium sulfate, ammonium chloride (usually
~7°5 mol/Q), ammonia water (normal concentration 10
~28%), ammonia gas, etc.

In the method of the present invention, the above three raw materials (a), (b) and (c) (hereinafter simply referred to as aqueous solutions) are continuously supplied to the reaction system. The feed ratio of the three types of aqueous solutions is 1.0 mol of the alkali metal hydroxide to 1 mol of the nickel salt in (a).
About 8 to 2.2 mol, ammonium ion donor 0.1
~1. 5mo/147! .

within the range of degrees. These three types of aqueous solutions are supplied to the reaction system while being sufficiently stirred. The amount of these aqueous solutions supplied varies depending on the capacity and shape of the reaction tank, the concentration of each aqueous solution, the desired particle size of nickel hydroxide, etc., but it should be such that the residence time in the reaction system is usually about 1 to 10 hours. Good.

The first to fourth inventions of the present application will be described in detail below with reference to the accompanying drawings.

(9) First invention of the present application and (1) Second invention of the present application Fig. 1 shows an outline of an example of a reaction apparatus used in carrying out the first invention and the second invention of the present application.

A reaction tank (1) equipped with a stirrer (17) is supplied with a nickel salt aqueous solution from a line (3), an ammonium ion donor from a line (5), and an alkali metal hydroxide aqueous solution from a line (7). Each is continuously supplied via a pump (9).

(11) is a pH controller, and (13) is a temperature controller. The liquid containing the generated nickel hydroxide particles is continuously taken out from the line (15). This liquid is filtered by known means to obtain desired nickel hydroxide particles.

When carrying out a reaction under the conditions shown in Figure 1, assuming that other conditions in the reaction system are constant, the relationship between the pn of the reaction solution and the ammonium ion concentration in the reaction solution is the growth rate of nickel hydroxide particles. has a major impact on That is, it is necessary to increase the ammonium ion concentration in the reaction solution as well as the pH of the reaction solution. For example, the pH of the reaction solution
Comparing the cases where 11.0 and 11.5, it is necessary to increase the ammonium ion concentration by about 1.5 times in the latter case. In this pH range, there is almost a proportional relationship between the pH value and the required ammonium ion concentration. Under these circumstances, by continuing the reaction with a constant ammonium ion concentration and a constant pH of the reaction solution (11,0), the reaction started after nickel hydroxide particles grew for a certain period of time. Assuming that the pH of the solution is increased to 11.5, in order to further increase the growth of nickel hydroxide particles, it is necessary to increase the concentration of ammonium ions to correspond to the increased pH value of the reaction solution. At this time, if the ammonium ion donor continues to be supplied at a concentration corresponding to the initial pH of the reaction solution (11,0>), the amount of ammonium ions will be insufficient and the nickel hydroxide particles generated so far will It was found that the growth almost stopped, and in its place, fine nickel hydroxide particles, which became new nickel hydroxide particle nuclei, were generated.

Also, when the supply of ammonium ion donor is stopped or significantly reduced while the pH of the reaction solution is kept constant, the amount of ammonium ions becomes insufficient and the water produced so far is It was found that the growth of nickel oxide particles almost stopped, and in their place, nickel hydroxide fine particles that became new nickel hydroxide particle nuclei were generated.

The first and second inventions of the present application were completed based on such knowledge regarding the interrelationship between the pH of the reaction solution and the ammonium ion concentration in the reaction solution.

The first invention of the present application is implemented, for example, as follows.

First, the reaction is carried out in a steady state while maintaining constant conditions such as the amount of nickel salt aqueous solution and ammonium ion donor supplied to the reaction system and the temperature of the reaction system, and then an aqueous alkali metal hydroxide solution is intermittently added to the reaction system. An operation in which the pH of the reaction system is rapidly raised by increasing the supply amount, maintained at that state for a certain period of time, and then the supply amount of the alkali metal hydroxide aqueous solution is reduced to a steady amount to return the initial pH again. Do the following. For example, as shown in Figure 2, after the reaction is carried out for X hours with the pH of the reaction system set to 11.0, the amount of alkali metal hydroxide aqueous solution supplied is rapidly increased at point A to raise the pH of the reaction system. is increased to 11.5 and this state is continued for 7 hours until point B. In this case, the average particle diameter of nickel hydroxide particles reaches its maximum value at point A, the amount of nickel hydroxide particles gradually increases from point A to point B, and the amount of nickel hydroxide particles reaches its maximum value at point B. shows. Subsequently, the pH of the reaction system was set to 11.0 again from point B to point D, and the reaction was carried out for X hours, and then at point D, the amount of aqueous alkali metal hydroxide solution supplied was rapidly increased. to adjust the pH of the reaction system to 11.
．． Increase it to 5 and repeat the same operation. Temperature of reaction system, steady pH value, pH steady state holding time (X), increase p
The H value, pH rise time (Y), etc. may vary depending on the concentration of the three types of aqueous solutions (a), (b) and (c), the desired average particle size and particle size distribution of nickel hydroxide, etc.
Normal temperature = constant value within the range of 20 to 80°C, steady pH value and rising pH value - constant value within the range of -9 to 12, X = 5
~30 hours, Y=0.5~3 hours. Thus, it has a constant particle size distribution, with an average particle size of 2 to 50 μm.
m, and a product in which almost all of the nickel hydroxide particles are spherical or approximately spherical can be obtained.

In the second invention of the present application, while supplying the aqueous nickel salt solution and the aqueous alkali metal hydroxide solution to the reaction system, and maintaining constant conditions such as the pH and temperature of the reaction system,
By intermittently stopping the supply of the ammonium ion donor or significantly reducing the supply amount, the ammonium ion concentration in the reaction system is rapidly decreased, and after maintaining this state for a certain period of time, the supply amount of the ammonium ion donor is reduced. Perform an operation to return the amount to a steady level. For example, as shown in Figure 3, after the reaction is carried out for X degrees by steadily supplying the ammonium ion donor to the reaction system, at point A, the supply of the ammonium ion donor is stopped or the supply amount is significantly reduced. This state is continued for Y' time up to point B°. In this case, the average particle diameter of nickel hydroxide particles reaches its maximum value at point A°, and A″
The amount of nickel hydroxide fine particles gradually increases from point B° to point B, and the amount of nickel hydroxide fine particles reaches a maximum value at point B°. Subsequently, after steadily supplying the ammonium ion donor to the reaction system from point B'' through point C to point D for X degrees, the supply of ammonium ion donor was stopped again at point D'. significantly reducing supply,
Repeat the same operation below. Temperature of the reaction system, pH value, constant amount supply time of ammonium ion donor (X”),
The supply stop or supply reduction time (Yo) of the ammonium ion donor depends on the concentration of the three types of aqueous solutions (a), (b), and (c), the desired average particle size and particle size distribution of nickel hydroxide, etc. Although it can vary, the normal temperature is -20~
Constant value within the range of 80°C, pH value = constant value within the range of 9 to 12, X' = about 5 to 30 hours, Y' = 0.5 to 3
It takes about an hour.

Thus, it has a constant particle size distribution, with an average particle size of 2 to 50
approximately μm in size, and almost all of the nickel hydroxide particles are
A spherical or approximately spherical product is obtained.

■0 Third invention of the present application and ■1 Fourth invention of the present application Fig. 4 shows an outline of an example of the apparatus used when carrying out the third invention and the fourth invention of the present application. This device basically has a structure in which two reaction devices shown in FIG. 1 are combined, and one mixing device is added.

In FIG. 4, each element of the reactor shown in the upper left is indicated by a number in the 100s, and each element of the reactor shown in the upper right is indicated by a number in the 200s. For example, (101)
and (201”) are both the reaction tank (
This shows a reaction tank with the same function as 1).

In the third and fourth inventions of the present application, the reaction tank (101
) and the reaction tank (201), by producing nickel hydroxide particles under different reaction conditions, products with different average particle diameters and particle size distributions can be obtained in each tank. That is, in the two reaction vessels, the nuclei of nickel hydroxide may be formed by changing the pH, or the nuclei of nickel hydroxide may be formed by stopping or decreasing the supply of the ammonium ion donor, or in addition, one of the reactors may be caused to form nuclei of nickel hydroxide. The nuclei of nickel hydroxide may be formed in one reaction tank by changing the pH, and the nuclei of nickel hydroxide may be formed in the other reaction tank by stopping or decreasing the supply of the ammonium ion donor. 2 obtained in this way
The seed nickel hydroxide particle-containing liquid is transferred from the respective product take-out lines (115) and (215) to the mixing tank (S
After being uniformly stirred by a stirrer (303), it is taken out from the final product take-out line (305). The obtained nickel hydroxide particle-containing liquid is subjected to a filtration treatment according to a conventional method to obtain desired nickel hydroxide particles.

According to the third and fourth inventions of the present application, the reaction tank (101
) and the reaction tank (201), it is possible to produce nickel hydroxide particles that are spherical or approximately spherical and have an arbitrary average particle size and particle size distribution within the range of about 2 to 50 μm. It is possible to manufacture.

Although FIG. 4 shows an embodiment using two reaction vessels, in the third and fourth inventions of the present application, three reaction vessels are used.
It is also possible to more precisely control the average particle size and particle size distribution of nickel hydroxide particles by producing particles with different average particle sizes and particle size distributions using multiple reaction vessels and mixing them. It is possible.

The nickel hydroxide particles obtained by the method of the present invention are useful as non-sintered nickel positive electrode materials for alkaline batteries, materials for surface treatment of steel plates, materials for nickel plating, and the like.

In addition, nickel hydroxide particles containing especially cobalt and cadmium are used as non-sintered nickel positive electrode materials for alkaline batteries, and have effects such as suppressing self-discharge in alkaline secondary batteries and improving charging efficiency of alkaline secondary batteries. Demonstrate.

Effects of the Invention According to the method of the present invention, the following remarkable effects can be achieved.

(a) Di-Nkel hydroxide particles having a spherical shape or an approximately spherical shape are obtained.

(b) Since the obtained nickel hydroxide particles are spherical or spherical, they have excellent filtration properties during production, are easy to remove impurities during production, and are easy to handle as a powder.
High tapping density.

(C) The average particle size and particle size distribution of nickel hydroxide particles can be easily controlled.

EXAMPLES Examples will be shown below to further clarify the features of the present invention.

Example 1 A reactor of the type shown in FIG. 1 was used to continuously produce nickel hydroxide particles under stirring.

The aqueous solutions used, reaction conditions, etc. are as follows. Note that the number of customers in reaction tank (1) was 100Q.

(a) Nickel salt aqueous solution: Concentration...nickel sulfate 2.2 mol/Q supply 1it=1
5. 9Q/hr (b) Alkali metal hydroxide aqueous solution: Concentration...sodium hydroxide 6.0 mol/Q supply amount...
・Maintain the pH of the reaction system in steady state at 11.0 ■ (Average supply 5 (1/hr)) (c) Ammonium ion donor: Concentration: 25% Ammonia water supply amount: 1.7R/ hr (d) Conditions in the reaction tank during steady state: pH...11.0 Temperature...50°C Exclude the initial product for 20 hours until the reaction reaches a stable state, and then continue under the same conditions. After continuing the reaction for 14 hours (X = 14 hours in Figure 2), the amount of sodium hydroxide aqueous solution supplied was increased to bring the pH of the reaction system to 11.
．． 5 and the reaction was carried out for 1 hour under these conditions (Y=1 hour in FIG. 2). Next, the pH of the reaction system was returned to 11.0, and the reaction was carried out in a steady state for 14 hours, and thereafter the reaction was repeated in the same cycle.

Scanning electron micrographs (approximately 500 times magnification) of nickel hydroxide particles at each time point corresponding to A to D in FIG. 2 are shown in FIGS. 5 to 8, respectively.

First, it is clear that the nickel hydroxide particles obtained at the time point corresponding to A (FIG. 5) have a spherical particle shape.

Furthermore, it is clear that the nickel hydroxide particles obtained at the time point corresponding to B (FIG. 6) contain fine particles that should become the nucleus for particle growth after boiling.

Further, in the nickel hydroxide particles obtained at the time point corresponding to C (FIG. 7), particles with an intermediate particle size are observed, indicating that the above-mentioned fine particles are growing.

The nickel hydroxide particles obtained at the time point corresponding to D (Fig. 8) have the same particle shape and particle size distribution as the nickel hydroxide particles obtained at the time point corresponding to A (Fig. 5). It is clear that

15, which corresponds to one cycle of the reaction from A to D above.
The average particle size of the product obtained by filtering the nickel hydroxide particles obtained during this period according to a conventional method, washing with water, and drying is 7.
．． 1 μm, and the tapping density is 2.02 g/ml
Met.

Since the obtained nickel hydroxide particles were spherical or spherical, they were easy to filter and easy to handle as a powder.

Example 2 Cobalt- and cadmium-containing nickel hydroxide particles were obtained in the same manner as in Example 1, except that the following aqueous solution was used in place of the nickel salt aqueous solution used in Example 1.

(a) Nickel salt aqueous solution containing cobalt and cadmium: Concentration: nickel sulfate 2.1 mol/Q cobalt sulfate 0
．． 03 mol/Q Cadmium sulfate 0.07 mol/Q Cobalt-cadmium-containing nickel hydroxide particles obtained during 15 hours corresponding to one cycle of the reaction from A to D in Figure 2° are filtered according to a conventional method. The average particle size of the product obtained by washing with water and drying was 6.8 μm, and the tapping density was 2.04 g/ml.

Further, the obtained cobalt-cadmium-containing nickel hydroxide particles were also spherical or spherical, and were easy to filter and handle as a powder.

Example 3 A reactor of the type shown in FIG. 1 was used to continuously produce nickel hydroxide particles under stirring.

The aqueous solutions used, reaction conditions, etc. are as follows.

(a) Nickel salt aqueous solution: Concentration: nickel sulfate 2.2 mol/Q supply ffl・-
45,99/hr (b) Alkali metal hydroxide aqueous solution: Concentration...sodium hydroxide 6.0 mol/Q supply n...
・Amount to maintain the pH of the reaction system at 11.0 (average supply amount C
B)/hr) (iii) Ammonium ion supplier: Concentration: 25% ammonia water supply amount: 1.7C/hr (steady state) (d) Conditions inside the reaction tank during steady state: pH...・11.0 Temperature: 50°C After excluding the initial product for 20 hours until the reaction reached a stable state, and continuing the reaction for another 14 hours under the same conditions (in Figure 3, X' = 14 hours), pH 11
．． The supply of the ammonium ion donor was stopped while the temperature was maintained at 0, and the reaction was carried out for 1 hour under these conditions (Y'' = 1 hour in Fig. 3).Then, the supply of the ammonium ion donor was restarted. The reaction was carried out in a steady state for 14 hours, and thereafter the reaction was repeated in the same cycle.

The concentration of ammonium ions in the reaction solution at the time point corresponding to A' (Figure 3) is 0.7%, and B' (
The concentration of ammonium ions in the reaction solution at the time point corresponding to FIG. 3) was 0.40%.

The nickel hydroxide particles obtained at each time point corresponding to A'B'C" and Do in FIG.
Almost the same as the nickel hydroxide particles obtained at each time point corresponding to B, C, and D, the shape was approximately spherical or almost spherical.

The average particle diameter of the product obtained by filtering the nickel hydroxide particles obtained during 15 hours corresponding to one cycle of the above reaction from Ao to D'' according to a conventional method, washing with water, and drying is 5. .8μm, and the tapping density is 2.03g/
It was ml.

Since the obtained nickel hydroxide particles were spherical or spherical, they were easy to filter and easy to handle as a powder.

Example 4 Cobalt and cadmium-containing nickel hydroxide particles were obtained in the same manner as in Example 3, except that the following aqueous solution was used in place of the nickel salt aqueous solution used in Example 3.

(a) Nickel salt aqueous solution containing cobalt and cadmium: Concentration: nickel sulfate 2.1 mol/Q cobalt sulfate 0
．． 03 mol/Q Cadmium sulfate 0.07 mol/Q Cobalt-cadmium-containing nickel hydroxide particles obtained during 15 hours corresponding to one cycle of the reaction from Ao to Do in Figure 3 were filtered according to a conventional method. The average particle diameter of the product obtained by washing with water and drying was 6.0 μm, and the tapping density was 2.04 g/ml.

Further, the obtained cobalt-cadmium-containing nickel hydroxide particles were also spherical or spherical, and were easy to filter and handle as a powder.

Example 5 Using a reaction apparatus of the type shown in FIG. 4, nickel hydroxide particles were continuously produced under stirring.

Reaction in A1 reaction tank (101): The aqueous solutions used, reaction conditions, etc. are as follows. The reactor capacity was 100Q.

(a) Nickel salt aqueous solution: Concentration: nickel sulfate 2.2 mol/Q supply amount: 8
．． CH! /hr (b) Alkali metal hydroxide aqueous solution: Concentration: Sodium hydroxide L, 6.0 mol/Q supply level.
...Amount to maintain the pH of the reaction system at 11.0 during steady reaction (average supply amount 4.512/hr) (iii) Ammonium ion donor: Concentration...25% Ammonia water supply amount...0゜9Q/hr (Steady state) (d) Conditions in the reaction tank during steady state: pH...11.0 Temperature...50°C Initial product for 20 hours until the reaction reaches a stable state After continuing the reaction for 15 hours under the same conditions (X = 15 hours in Figure 2), the amount of sodium hydroxide aqueous solution supplied was increased to bring the pH of the reaction system to 11.
．． 5 and the reaction was carried out for 1 hour under these conditions (Y=1 hour in FIG. 2). Next, the pH of the reaction system was returned to 11.0, and the reaction was carried out in a steady state for 15 hours, and thereafter the reaction was repeated in the same cycle.

Reaction in B0 reaction tank (201): Each aqueous solution used, reaction conditions, etc. are as follows. The reactor capacity was 50Q.

(a) Nickel salt aqueous solution: Concentration...nickel sulfate 1.1 mol/Q supply amount...4
．． OQ/hr (b) Alkali metal hydroxide aqueous solution: Concentration...sodium hydroxide 3.0 mol/Q supply amount...
・Amount to maintain the pH of the reaction system at 11.0 during steady reaction (
Average supply amount: 2.25Q/hr) (c) Ammonium ion supplier: Concentration: 12.5% Ammonia water supply amount: 0.45Q/hr (steady state) (d) Reaction tank in steady state Internal conditions: pH...11.0 Temperature...50°C After excluding the initial product for 20 hours until the reaction reached a stable state, and continuing the reaction for another 15 hours under the same conditions (second In the figure, the pH of the reaction system was increased to 11 hours by increasing the amount of sodium hydroxide aqueous solution supplied (X = 15 hours).
．． 5 and the reaction was carried out for 1 hour under these conditions (Y=1 hour in FIG. 2). Next, the pH of the reaction system was returned to 11.0, and the reaction was carried out in a steady state for 15 hours, and thereafter the reaction was repeated in the same cycle.

Mixing operation in the C1 mixing tank (301): The liquid containing nickel hydroxide particles obtained in the reaction layers (101) and (201), respectively, is continuously fed into the lines (115) and (2).
15) to a mixing tank (301), and after thorough mixing, it was filtered, washed with water, and dried according to a conventional method. The obtained nickel hydroxide particles were spherical or spherical regardless of the particle size, and were easy to filter and handle as a powder. In addition, the average particle diameter is 7.5 μm
The tapping density was 2.12 g/ml.

Example 6 (A) Cobalt and cadmium-containing hydroxide was prepared in the same manner as in Step A of Example 5, except that the following aqueous solution was used in place of the nickel salt aqueous solution used in Step A of Example 5. Nickel particles were obtained.

Concentration...nickel sulfate 2.1 mol/Q cobalt sulfate 0
．． 03 mol/Q Cadmium sulfate 0.07 mol/g (B) The same operation as in Step B of Example 5 was performed except that the following aqueous solution was used in place of the nickel salt aqueous solution used in Step B of Example 5. As a result, cobalt and cadmium-containing nickel hydroxide particles were obtained.

Concentration: Nickel sulfate 1.05 mol/Q Cobalt sulfate 0.015 mol/Q Cadmium sulfate 0.035 mol/Q (C) The nickel hydroxide particle-containing liquid obtained in steps (A) and (B) above Continuously line (115) and (215)
After being sent to the mixing tank (301') and thoroughly mixed,
It was filtered, washed with water, and dried according to a conventional method.

The obtained nickel hydroxide particles were spherical or spherical regardless of the particle size, and were easy to filter and handle as a powder. In addition, the particle size and particle size distribution of the nickel hydroxide particles were also almost the same as in the case of Jitsutetsu 5.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing an example of a reaction apparatus used in carrying out the method of the present invention. FIG. 2 is a diagram showing an example of pH adjustment performed when carrying out the method of the present invention. FIG. 3 is a diagram showing an example of the addition adjustment of the ammonium ion donor performed when carrying out the method of the present invention. FIG. 4 is a flowchart showing another example of the reaction apparatus used in carrying out the method of the present invention. FIG. 5 is a scanning electron micrograph of nickel hydroxide particles obtained at the corresponding time point corresponding to A in FIG. FIG. 6 is a scanning electron micrograph of nickel hydroxide particles obtained at the corresponding time point corresponding to B in FIG. FIG. 7 is a scanning electron micrograph of nickel hydroxide particles obtained at the corresponding time point corresponding to C in FIG. FIG. 8 is a scanning electron micrograph of nickel hydroxide particles obtained at the corresponding time point corresponding to D in FIG. (1)...Reaction tank (3)...Nickel salt aqueous solution supply line (5)...
Ammonium ion supplier supply line (7)...alkali metal hydroxide aqueous solution supply line (
9) Metering pump (11)...pH controller (13)...temperature controller (15)...nickel hydroxide particle-containing liquid extraction line (17)...stirrer (101'')...reaction Tank (103)... Nickel salt aqueous solution supply line (105
)・-・Ammonium ion donor supply line (107
)... Alkali metal hydroxide aqueous solution supply line (109) Metering pump (111)... pH controller (113)... Temperature controller (115)... Nickel hydroxide particle-containing liquid take-out line (117) ... Stirrer (201) ... Reaction tank (203) ... Nickel salt aqueous solution supply line (205
)...Ammonium ion donor supply line (20
7>...Alkali metal hydroxide aqueous solution supply line (209>metering pump (211)...pH controller (213)...temperature controller (215)...nickel hydroxide particle-containing liquid extraction line (217 )...Stirrer (301)...Mixing tank <303)...Stirrer (and above) 3 Procedural Juho Seisho (spontaneous) Display of the case 1990 Patent Application No. 48028 Name of the invention Person who amends the manufacturing method of nickel hydroxide Relationship to the case Patent applicant Kansai Catalyst Chemical Co., Ltd.

Claims (4)

[Claims] (1) Continuously supply (a) a nickel salt aqueous solution or an aqueous solution containing a nickel salt, a cobalt salt, and a cadmium salt, (b) an alkali metal hydroxide aqueous solution, and (c) an ammonium ion donor to the reaction system, and react. Nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium are produced by proceeding the reaction while maintaining the temperature of the system at a constant value within the range of 20 to 80°C and the pH at a constant value within the range of 9 to 12. In this method, the amount of aqueous alkali metal hydroxide solution is intermittently increased over a certain period of time to adjust the pH of the reaction system, thereby removing the core hydroxide. A method for producing spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium, the method comprising producing nickel fine particles. (2) Continuously supply (a) a nickel salt aqueous solution or an aqueous solution containing a nickel salt, a cobalt salt, and a cadmium salt, (b) an alkali metal hydroxide aqueous solution, and (c) an ammonium ion donor to the reaction system, and react. Nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium are produced by proceeding the reaction while maintaining the temperature of the system at a constant value within the range of 20 to 80°C and the pH at a constant value within the range of 9 to 12. In the method of producing ammonium ion donor and continuously taking out the product, the core water is removed by intermittently stopping the supply of the ammonium ion donor to the reaction system for a certain period of time or reducing the supply amount. A method for producing spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium, the method comprising producing nickel oxide fine particles. (3) Continuously supply (a) a nickel salt aqueous solution or an aqueous solution containing a nickel salt, a cobalt salt, and a cadmium salt, (b) an alkali metal hydroxide aqueous solution, and (c) an ammonium ion donor to the reaction system, and react. Nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium are produced by proceeding the reaction while maintaining the temperature of the system at a constant value within the range of 20 to 80°C and the pH at a constant value within the range of 9 to 12. In this method, the reaction is carried out under different conditions in multiple reaction systems to form particle groups with different particle sizes, and the reaction is carried out intermittently over a certain period of time in each reaction system. By increasing the supply amount of the alkali metal hydroxide aqueous solution and adjusting the pH of the reaction system, nickel hydroxide fine particles that serve as the core are generated, and by mixing the particle groups with different particle sizes obtained above. A method for producing spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium, the method comprising obtaining mixed particles having a predetermined particle size distribution. (4) Continuously supply (a) a nickel salt aqueous solution or an aqueous solution containing a nickel salt, a cobalt salt, and a cadmium salt, (b) an alkali metal hydroxide aqueous solution, and (c) an ammonium ion donor to the reaction system, and react. Nickel hydroxide particles or nickel hydroxide particles containing cobalt and cadmium are produced by proceeding the reaction while maintaining the temperature of the system at a constant value within the range of 20 to 80°C and the pH at a constant value within the range of 9 to 12. In this method, the reaction is carried out under different conditions in multiple reaction systems to form particle groups with different particle sizes, and the reaction is intermittently carried out for a certain period of time in each reaction system. By stopping the supply of the ammonium ion donor to the reaction system or reducing its supply amount, nickel hydroxide fine particles serving as the nucleus are generated,
Spherical nickel hydroxide particles or spherical nickel hydroxide particles containing cobalt and cadmium characterized in that mixed particles having a predetermined particle size distribution are obtained by mixing the particle groups with different particle sizes obtained above. manufacturing method.