CN1075697A - Preparation method of corpuscle ball type nickel hydroxide - Google Patents

Abstract

The invention discloses a kind of method for making of spherical nickel hydroxide particle, it is characterized in that nickel salt solution and continuous importing of caustic solution are had in the reaction solution of stable ammonia, ammonium content, control reacting liquid pH value, temperature, reactant mean residence time and agitation condition make nickel hydroxide crystallize out with spheroidal particle.The method of ammonia, ammonium content is to add a certain proportion of ammonia in caustic solution, or adds a certain proportion of ammonium salt in nickel salt solution in the control reaction solution, or ammoniacal liquor or ammonium salt solution are also added separately continuously.Product loose density 1.4～1.8 grams per milliliters, tapped density 1.8～2.2 grams per milliliters are cadmium nickel and ni-mh rechargeable battery ideal positive electrode material.

Description

Preparation method of corpuscle ball type nickel hydroxide

The invention belongs to the manufacturing process of spherical nickel hydroxide particle.This method for making is characterised in that nickel hydroxide is to separate out in the alkali reaction liquid in the presence of the ammonia of stable content, ammonium are arranged.

Mainly as the positive active material of ickel-cadmium cell and Ni-H cell, general traditional method for making is nickel hydroxide at present: nickel sulfate solution is sprayed quinoline in the solution of the sodium hydroxide of continuous stirring, keep solution that 5～10% excess base is arranged when reaction finishes; Ageing a couple of days, the colloidal precipitation thing of generation separates with mother liquor through press filtration; Filter cake carries out drying under 110～140 ℃, thorough washing makes sulfate radical content be not more than 1%; In 110～140 ℃ of redryings, pulverized 420 μ (sieve diameter is once called as 40 orders) sieve, get product.(Song Wenshun, " chemical power source technology ", Light Engineering Institutes Of Zhengzhou's teaching material, 1990:220).Also have certain methods,, add the method (special public clear 53～No. 6119, the spy opens clear 56～No. 143671, the spy opens clear 61～No. 181074) of caustic alkali precipitation nickel hydroxide then as in nickel salt solution, adding ammonium salt or making nickel ammine earlier; Nickel salt solution is reinforced simultaneously continuously by overflowing the continuous processing (spy opens clear 63～No. 1655, and the spy opens clear 63～No. 1656) that suspension liquid separates hydrogen-oxygen nickel with caustic solution.The nickel hydroxide solid that all these methods make all needs to pulverize, thereby becomes the erose powder that broadwise out section is arranged, and size-grade distribution is extremely wide, and tamped density is hanged down (see figure 2).

The up-to-date method for making of nickel hydroxide has been announced in day disclosure special permission: import nickel nitrate solution and caustic solution in first reactive tank continuously simultaneously, the control pH value is 10.4～10.7, after the nickel hydroxide suspension liquid that generates overflows, import in second reactive tank again continuously, simultaneously also import nickel nitrate solution and caustic solution continuously in second reactive tank, the amount of the nickelous nitrate of importing is 5～20% of first reactive tank.Control second reactive tank PH=10.8～11.3, the suspension liquid that overflows from the 2nd reactive tank can obtain stable ball-shape nickel hydroxide product, and tapped density can reach 1.7～1.9 grams per milliliters (spy opens flat 1～No. 187765).

This spherical nickel hydroxide particle is suitable for the manufacturing of nickel electrode very much, but because complex process is restive, is easy to generate the colloid nickel hydroxide, brings difficulty to the producer.

Purpose of the present invention and task are to develop a kind of manufacture method of being convenient to control and be convenient to the spherical nickel hydroxide particle of suitability for industrialized production.This nickel hydroxide density is big, and narrower particle size distribution is as electrode active material and the mashed prod good fluidity of making after conductive agent mixes, tamped density height.This is at present for improving the positive electrode active materials that ickel-cadmium cell and Ni-H cell specific storage are badly in need of.

For solving above-mentioned task, the solution that the present invention adopts is: nickel salt solution and caustic solution are added reactor continuously, allow nickel hydroxide crystallization in the alkali reaction liquid that stable ammonia, ammonium content are arranged also take out continuously.The method that keeps stable ammonia, ammonium content in the reaction solution is to add a certain proportion of ammonium salt in nickel salt solution, or adds a certain proportion of ammonia or ammonia, ammonium also added separately continuously in caustic solution and realize in the reaction solution.

In other words, the invention relates to the manufacturing process of spherical nickel hydroxide particle, it is characterized by reactant and be the nickel nitrate solution of the nickel sulfate solution of 0.5～1.7 mol or 1.0～3.5 mol and contain the caustic solution of 2～12 mol of caustic alkali mole number 2.5～35% ammonia; Its optimum concn is the nickel sulfate solution of 2～2.5 moles nickelous nitrate or 1.4～1.6 mol and the caustic solution that contains 4～8 mol of caustic alkali mole number 10～25% ammonia.Reactant also can be " nickel sulfate solution of 2～2.5 mol nickelous nitrates or 0.5～1.7 mol " and the caustic solution of 2～12 mol that contains nickel salt mole number 5～60% ammonium salts (I); Optimum concn is for containing " nickel sulfate solutions of the nickelous nitrate of 2～2.5 mol or 1.4～1.6 mol " and the caustic solution of 4～8 mol of nickel salt mole number 30～45% ammonium salts (I).Reactant can also be the nickel nitrate solution of 1.0～3.5 mol or the nickel sulfate solution of 0.5～1.7 mol, and the ammonia solution of 2～12 mol caustic solutions and 4～14 mol presses 1.0 than the mol ratio adding reactor of 1.8-2.2 than 0.6-0.05; Its optimum concn is the nickel sulfate solution of 2～2.5 molar nitric acid nickel or 1.4～1.6 mol, and the ammoniacal liquor of the caustic solution of 4～8 mol and 10～13 mol is determined relative discharge than 1.9-2.1 than the mol ratio of 0.2-0.5 by 1.0.Reactant mean residence time in reactor can be selected between 5～100 hours, and optimum value is 10～24 hours, realized by adjusting nickel salt solution and alkali lye relative discharge, and temperature can be selected between room temperature to 80 ℃, and optimum value is 55～65 ℃; The pH value of reaction solution is selected between 8.5～11.5, and optimum value is 9.5～10.5, realizes by adjusting nickel salt and alkali lye relative velocity.In above-mentioned scope, adjust these parameters or change the solid-to-liquid ratio of reacting suspension liquid, can control the size of nickel hydroxide particulate.

By above-described reaction conditions, reactant adding continuously has adding a cover in the reactor of feed distributor and stirring, reacts, after reaction system is stable, take out the spherical nickel hydroxide particle of the phase of giving continuously,, get product through solid-liquid separation, washing, oven dry.

Advantage of the present invention and positively effect: (1) easy control of reaction conditions, even level of automation is not high, manual operations also can reach the purpose of the spherical nickel hydroxide particle product that stably produces the phase of giving, and reactor throughput height, one 2 cubic metres retort, day output can be selected between 100～760 kilograms, and optimum yield is 200～500 kilograms.Because product washs easily, only need oven dry once, do not need any pulverizing process again, simplified production technique greatly, alleviated labour intensity.(2) products obtained therefrom is the spherical particle with smooth surface, and shown in Fig. 3-5, loose density is 1.4～1.8 grams per milliliters, and tapped density is 1.8～2.2 grams per milliliters.Median size is controlled at No. 5 ickel-cadmium cell positive plates of making by same weight between 3～30 microns as required, and the thickness ratio reduces 25% when using traditional product, provides condition for improving cell container, and the nickel electrode manufacturing process also improves.

Fig. 1, for can be used for reactor assembly synoptic diagram of the present invention.

Fig. 2, be traditional processing technology product stereoscan photograph.

Fig. 3, be that embodiment of the invention products obtained therefrom amplifies 700 times stereoscan photograph.

Fig. 4, products obtained therefrom amplifies 700 times stereoscan photograph when increasing the residence time for the embodiment of the invention.

Fig. 5, with the stereoscan photograph of Fig. 4 for 2500 times of identical product amplifications.

Describe optimum implementation of the present invention in detail below in conjunction with Fig. 1.The manufacturing of nickel hydroxide is undertaken by the reaction unit of structure as shown in Figure 1, and 2 cubic metres of retort 1 have agitator 6 and feed distributor 10 and lid 11.The preparation reaction solution: join the nickel nitrate solution of proportion 1.17 under the room temperature, concentration is about 2.3 mol, joins the sodium hydroxide solution of proportion 1.22 under the room temperature, and concentration is about 6.2 mol; Ammonia is fed the ammoniacal liquor of making proportion 0.91 in the water, and concentration is about 12.8 mol.Earlier nickel nitrate solution is sent in the nickel nitrate solution header tank; By the order of alkali lye behind the first ammoniacal liquor ammoniacal liquor and alkali lye are delivered in the alkali liquid high-level groove of adding a cover, and it is mixed, the two volume ratio is an alkali: ammoniacal liquor=100: 8, the mol ratio of ammonia and sodium hydroxide is about 16.5: 100.Reacting liquid temperature controls to 55～65 ℃ by steam heating in the retort chuck by the tolerance size, reads from thermometer 2.Determine the nickel nitrate solution flow earlier according to producing needs, nickel nitrate solution, enters in the reaction solution after sparger 10 decomposes through under meter 6 dominant discharge by nickel nitrate solution filling tube 7; Contain ammonia alkali liquid and pass through alkali lye feed-pipe 8 through under meter 6 dominant discharge, enter in the reaction solution after sparger 10 disperses, the requirement of regulating this under meter 6 is that the reaction solution pH value is remained in 10 ± 0.5, and pH value is measured by PH meter 5.The steady periodic flow velocity of reaction system is 80 liters/hour of nickel nitrate solutions, and contain the ammonia alkali flow velocity and be about 65 liters/hour this moment, and reaction mixture is about 12 hours at the reactor mean residence time.The rotating speed of reactor stirring 6 is 85～90 rev/mins.The suspension liquid that contains nickel hydroxide and other product after the reaction takes out continuously through bottom discharge mouth 4 or top upflow tube 3, through solid-liquid separation, washing, oven dry, gets product.Product loose density 1.78 grams per milliliters, tapped density 2.16 grams per milliliters, 9.1 microns (see figure 3)s of median size; Increase residence time to 24 hour and suitably the augmenting response solid and liquid than the time median size increase to 17.5 microns (seeing Fig. 4, Fig. 5).

Claims (6)

1, the invention belongs to the manufacturing process of spherical nickel hydroxide particle, also be that nickel salt solution and alkali lye are imported reactor and continuous continuous processing of taking out product continuously, it is characterized in that reactant both can be the nickel nitrate solution of 1.0～3.5 mol or 0.5～1.7 nickel sulfate solution and the caustic solution that contains 2～12 mol of caustic alkali mole number 2.5～35% ammonia, also can be " nickel sulfate solution of the nickel nitrate solution of 1.0～3.5 mol or 0.5～1.7 mol " that contains nickel salt mole number 5～60% ammonium salts (1); Can also be the nickelous nitrate of 1.0～3.5 mol or nickel sulfate solution and the caustic solution of 2～12 mol and the ammonia solution of 4～14 mol of 0.5～1.7 mol, determine its relative discharge than 1.8-2.2 than the mol ratio of 0.6-0.05 by 1.0, allowing and being reflected at pH value 8.5～11.5, reactant mean residence time in adding a cover reactor is to carry out under 5～100 hours, 10～80 ℃ of temperature and the agitation condition, make nickel hydroxide from the reaction solution that stable ammonia, ammonium content are arranged, carry out crystallization, grow up to spherical particle.

2, method according to claim 1 is characterized in that reactant is the nickelous nitrate of 2～2.5 mol or the single nickel salt and the caustic solution that contains 4～8 mol of caustic alkali mole number 10～25% ammonia of 1.4～1.6 mol.

3, method according to claim 1 is characterized in that reactant is " nickel sulfate solutions of 2～2.5 mol nickelous nitrates or 1.4～1.6 mol " and the caustic solution of 4～8 mol that contains nickel salt mole number 30～45% ammonium salts (1).

4, method according to claim 1, it is characterized in that reactant is the nickelous nitrate of 2～2.5 mol or the nickel sulfate solution of 1.4～1.6 mol, the ammoniacal liquor of the caustic solution of 4～8 mol and 10～13 mol is determined three relative discharge than 1.9-2.1 than 0.5-0.2 mol ratio by 1.0.

5, according to any one described method of claim 1-4, it is characterized in that reaction conditions is PH=9.5-11, reactant mean residence time in retort is 10～24 hours, 55～65 ℃ of temperature and fully stirring.

6,, it is characterized in that reactor has feed distributor and lid according to any one described method of claim 1-4.

Images