CN111874957A

CN111874957A - Production process of cobaltosic oxide precursor for superfine cobalt powder

Info

Publication number: CN111874957A
Application number: CN202010614123.XA
Authority: CN
Inventors: 许开华; 唐洲; 白亮; 陈龙; 杨春; 吴兵
Original assignee: Jingmen GEM New Material Co Ltd
Current assignee: Jingmen GEM New Material Co Ltd
Priority date: 2020-06-30
Filing date: 2020-06-30
Publication date: 2020-11-03

Abstract

The invention discloses a production process of a cobaltosic oxide precursor for superfine cobalt powder, which comprises the following steps: taking a cobalt solution obtained by leaching, extracting and purifying recovered cobalt-containing waste as a raw material; taking an ammonium bicarbonate solution as a precipitator: preparing a cobalt solution with a certain concentration as a cobalt source and an ammonium bicarbonate solution; when the reaction starts, adding the ammonium bicarbonate solution and pure water into a reaction kettle, starting stirring, adding the cobalt solution and the ammonium bicarbonate into the reaction kettle simultaneously, reacting under the stirring condition, and finally obtaining the cobaltosic oxide precursor for the superfine cobalt powder by controlling certain process conditions. The cobaltosic oxide precursor for the superfine cobalt powder produced by the preparation method has the appearance of agglomerated cobalt carbonate with good primary particle sphericity and large particle size, is difficult to sinter, has high yield and good fluidity in the sintering process after being calcined, and can be decomposed into spherical cobaltosic oxide particles.

Description

Production process of cobaltosic oxide precursor for superfine cobalt powder

Technical Field

The invention belongs to the field of preparation of inorganic functional materials, and particularly relates to a production process of a cobaltosic oxide precursor for superfine cobalt powder.

Background

The cobaltosic oxide is a functional material with special structure and performance, is a main raw material for preparing lithium cobaltate serving as a positive electrode material of a lithium ion battery, and meanwhile, cobaltosic oxide powder is widely applied to the fields of supercapacitors, hard alloys, pressure-sensitive ceramics, inorganic pigments, catalysts and the like.

At present, the superfine cobalt powder is generated by calcining fine-particle cobalt carbonate by using cobaltosic oxide, the fine-particle cobalt carbonate is easy to sinter into lumps, the yield is low, the produced superfine cobalt powder is poor in appearance, and the phenomenon of cobalt pool generation in high-cobalt hard alloy caused by coarse particles is easy to occur.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a production process of a cobaltosic oxide precursor for superfine cobalt powder.

The invention is realized by the following technical scheme.

A production process of a cobaltosic oxide precursor for superfine cobalt powder comprises the following steps:

1) raw materials: taking a cobalt solution obtained by leaching, extracting and purifying recovered cobalt-containing waste as a raw material; taking an ammonium bicarbonate solution as a precipitator:

2) preparing liquid: preparing a cobalt solution with the cobalt concentration of 100-160g/L and preparing an ammonium bicarbonate solution with the cobalt concentration of 200-300 g/L;

3) reaction: 1 to 3m³The ammonium bicarbonate solution is 1-1.5m³Adding pure water into a reaction kettle, starting stirring, adding the cobalt solution and ammonium bicarbonate into the reaction kettle at the same time, reacting under the stirring condition, controlling the flow rate of the cobalt solution to be 800L/h, the flow rate of the ammonium bicarbonate to be 1200L/h, the reaction temperature to be 50-60 ℃, the stirring speed to be 300-400r/min, and the reaction retention time to be 6-7 h; after the reaction is finished, aging for 0.5-2 h;

4) washing and drying: and washing and drying the aged material to obtain a cobaltosic oxide precursor for the superfine cobalt powder.

Wherein, the washing adopts a two-in-one washing machine to extrude mother liquor, adopts hot pure water to carry out slurrying washing, and repeats washing for 3-5 times.

Wherein, the drying condition is that the materials are statically dried at the temperature of 100 ℃ and 150 ℃ after the washing is finished.

Wherein, the volume of the reaction kettle adopted by the invention is 20m³。

In the step 4), the physicochemical indexes of the cobaltosic oxide precursor for the superfine cobalt powder are as follows: particle size distribution: d103-5 μm, D5015-25 μm, and D9030-45 μm; bulk density AD: 0.7-1.1g/cm³(ii) a Fisher-size FSSS: 0.16-0.32 μm.

The preparation method has the beneficial technical effects that the cobaltosic oxide precursor (cobalt carbonate) for the superfine cobalt powder, prepared by the preparation method, is in the shape of agglomerated cobalt carbonate with good primary particle sphericity and large particle size, is difficult to sinter, has high yield and good fluidity in the sintering process after being calcined, and can be decomposed into spherical cobaltosic oxide particles.

Drawings

FIG. 1 is an SEM image of the detection result of the product prepared by the invention.

Detailed Description

The present invention will be described in detail with reference to the following embodiments.

Example 1:

the production steps are the same as above and are not described herein again. The specific parameters in each step are as follows:

2) preparing liquid: preparing a cobalt solution with the cobalt concentration of 160g/L and preparing an ammonium bicarbonate solution with the concentration of 300 g/L;

3) reaction: 2.5m³1.3m of the ammonium bicarbonate solution³Adding pure water into a reaction kettle, starting stirring, adding the cobalt solution and ammonium bicarbonate into the reaction kettle at the same time, reacting under the stirring condition, controlling the flow rate of the cobalt solution to be 700L/h, the flow rate of the ammonium bicarbonate to be 1500L/h, the reaction temperature to be 53 +/-2 ℃, the stirring speed to be 350r/min, and the reaction retention time to be 6.0 h; after the reaction is finished, aging for 1.5 h;

4) washing and drying: and extruding the aged material out of a mother solution by using a two-in-one washing machine, pulping and washing by using hot pure water, repeatedly washing for 3 times, and statically drying the material at 120 ℃ after washing is finished to obtain a cobaltosic oxide precursor for superfine cobalt powder.

The indexes of the prepared product are particle size distribution: d105 μm, D5024 μm, D9042 μm, apparent density: 1.05g/cm3, Fisher size FSSS: 0.32 μm spherical or sphere-like superfine cobalt powder is used as a cobaltosic oxide precursor.

Example 2:

2) preparing liquid: preparing a cobalt solution with the cobalt concentration of 130g/L and preparing an ammonium bicarbonate solution with the concentration of 260 g/L;

3) reaction: 1.8m³1.2m of the ammonium bicarbonate solution³Adding pure water into a reaction kettle, starting stirring, adding the cobalt solution and ammonium bicarbonate into the reaction kettle at the same time, reacting under the stirring condition, controlling the flow rate of the cobalt solution to be 700L/h, the flow rate of the ammonium bicarbonate to be 1500L/h, the reaction temperature to be 55 +/-2 ℃, the stirring rotation speed to be 350r/min, and the reaction retention time to be 6.5 h; after the reaction is finished, aging for 1.5 h;

4) washing and drying: and extruding the aged material out of a mother solution by using a two-in-one washing machine, pulping and washing by using hot pure water, repeatedly washing for 3 times, and statically drying the material at 140 ℃ after washing is finished to obtain a cobaltosic oxide precursor for superfine cobalt powder.

The indexes of the prepared product are particle size distribution: d103.5 μm, D5018 μm, D9036 μm, apparent density: 0.85g/cm³And FSSS: 0.27 mu m spherical or sphere-like superfine cobalt powder is used as a cobaltosic oxide precursor.

Example 3:

2) preparing liquid: preparing a cobalt solution with the cobalt concentration of 105g/L and preparing an ammonium bicarbonate solution with the concentration of 210 g/L;

3) reaction: 1.2m³1.4m of the ammonium bicarbonate solution³Adding pure water into a reaction kettle, starting stirring, adding the cobalt solution and ammonium bicarbonate into the reaction kettle at the same time, reacting under the stirring condition, controlling the flow rate of the cobalt solution to be 610L/h, the flow rate of the ammonium bicarbonate to be 1250L/h, the reaction temperature to be 58 +/-2 ℃, the stirring rotation speed to be 310r/min, and the reaction retention time to be 7.0 h; after the reaction is finished, aging for 1.0 h;

4) washing and drying: and extruding the aged material out of a mother solution by using a two-in-one washing machine, slurrying and washing by using hot pure water, repeatedly washing for 5 times, and statically drying the material at 105 ℃ after washing is finished to obtain a cobaltosic oxide precursor for the superfine cobalt powder.

The indexes of the prepared product are particle size distribution: d103.1 μm, D5016 μm, D9032 μm, apparent density: 0.8g/cm3, FSSS: 0.17 μm spherical or sphere-like superfine cobalt powder is used as a cobaltosic oxide precursor.

According to the invention, the ammonium bicarbonate solution and the cobalt solution are proportioned, primary particles with high sphericity are produced in an induction manner, primary particle aggregates are formed at a reasonable rotating speed, the appearance of the primary particle aggregates cannot be damaged when the primary particle aggregates are washed, the appearance of the primary particle aggregates is maintained after drying, and the obtained precursor has large particle size, high loose packing and large FSSS; the cobalt oxide is decomposed into spherical cobaltosic oxide particles during calcination.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention. It should be noted that other equivalent modifications can be made by those skilled in the art in light of the teachings of the present invention, and all such modifications can be made as are within the scope of the present invention.

Claims

1. A production process of a cobaltosic oxide precursor for superfine cobalt powder is characterized by comprising the following steps:

3) reaction: 1 to 3m³The ammonium bicarbonate solution is 1-1.5m³Adding pure water into the reaction kettle as a base solution, starting stirring, adding the cobalt solution and ammonium bicarbonate into the reaction kettle at the same time, reacting under the stirring condition, controlling the flow rate of the cobalt solution to be 800L/h, the flow rate of the ammonium bicarbonate to be 1200L/h, the reaction temperature to be 50-60 ℃, the stirring rotation speed to be 300-400r/min, and the reaction retention time to be 6-7 h; after the reaction is finished, aging for 0.5-2 h;

2. The process for producing a cobaltosic oxide precursor for ultrafine cobalt powder according to claim 1, wherein the washing is performed by extruding a mother liquor by a two-in-one washing machine, slurrying and washing with hot pure water, and repeating the washing 3-5 times.

3. The process for producing a cobaltosic oxide precursor for ultrafine cobalt powder as claimed in claim 1, wherein the drying is carried out under the conditions of 100-150 ℃ static drying of the washed material.

4. The process for producing a cobaltosic oxide precursor for superfine cobalt powder as claimed in claim 1, wherein in the step 4), the physicochemical indexes of the cobaltosic oxide precursor for superfine cobalt powder are as follows: particle size distribution PSD: d103-5 μm, D5015-25 μm, and D9030-45 μm; bulk density AD: 0.7-1.1g/cm³(ii) a Fisher-size FSSS: 0.16-0.32 μm.