CN108311710B

CN108311710B - Preparation method of monodisperse antioxidant nano-scale nickel powder

Info

Publication number: CN108311710B
Application number: CN201810165173.7A
Authority: CN
Inventors: 刘海涛; 曹海琳; 翁履谦
Original assignee: Shenzhen Aerospace New Material Technology Co ltd; Shenzhen Academy of Aerospace Technology
Current assignee: Shenzhen Aerospace New Material Technology Co ltd; Shenzhen Academy of Aerospace Technology
Priority date: 2018-02-28
Filing date: 2018-02-28
Publication date: 2021-02-09
Anticipated expiration: 2038-02-28
Also published as: CN108311710A

Abstract

The invention belongs to the field of nano material preparation, and provides a preparation method of monodisperse antioxidant nano nickel powder, which specifically comprises the following steps: placing an organic solvent containing nickel salt, an alkaline compound and a surfactant in a closed reaction kettle, reacting for 2-10h at the temperature of 150 ℃ and 250 ℃, and then centrifuging, washing and vacuum drying to obtain the monodisperse antioxidant nanoscale nickel powder. The nano nickel powder with good dispersibility is prepared by a one-step method, the particle size distribution of the obtained nickel powder is narrow, grading treatment is not needed, and the system is easy to carry out centrifugal separation and purification. On the other hand, the surface of the obtained nano nickel powder is coated with a small amount of organic coating, so that the oxidation resistance of the nano nickel powder can be improved.

Description

Preparation method of monodisperse antioxidant nano-scale nickel powder

Technical Field

The invention relates to a preparation method of nickel powder, in particular to a preparation method of monodisperse antioxidant nanoscale nickel powder, belonging to the field of preparation of nano materials.

Background

The nickel powder has the characteristics of good conductivity, chemical stability, weldability, welding resistance and the like, and is low in price, so that noble metals such as gold, silver and the like are gradually replaced in recent years and applied to the field of conductive paste, and the prepared conductive paste has the advantages of low resistance, good welding resistance, no ion migration, good linearity, resolution, silk-screen printing performance and the like, is widely applied to the electronic industries such as thick film hybrid integrated circuits, resistors, multilayer ceramic capacitors, resistor networks, sensitive component surface assembly technologies and the like, and becomes one of the most effective means for reducing the cost of current electronic products. However, the requirements of these precise and miniature electronic components on the used superfine nickel powder are extremely high, and the nickel powder must have good dispersibility and a size reaching the nanometer level to meet the requirements.

There are three main methods for preparing nickel powder: the first method is a hydrazine hydrate reduction method, and nickel ions are reduced by using reduction substances such as hydrazine hydrate, sodium borohydride, potassium borohydride and the like to obtain metallic nickel, but the method has a plurality of involved sensitive reaction parameters, has poor batch stability and is difficult to realize large-scale industrial production; secondly, a heating evaporation method is adopted, nickel is evaporated by utilizing energy applied by plasma or laser, and then metal powder is obtained in a low-temperature chamber, the method has large equipment cost investment and high cost, and the obtained nickel powder has wide particle size distribution and needs to be subjected to grading treatment; and thirdly, a polyol reduction method, wherein the polyol is mainly used for reducing nickel hydroxide to obtain the nano nickel, but the process of the method is not mature, and the prepared particles are not uniform. Meanwhile, the polyol system has high viscosity, and the nickel powder and the polyol are difficult to separate.

For example, CN103962570A discloses a method for preparing nano nickel powder, which comprises dissolving nickel salt and surfactant in water, stirring, adding complexing agent into the nickel salt solution, mixing, reacting to obtain a complex nickel salt solution as solution a, and dissolving reducing agent and alkali in water to obtain solution B; heating the solution A, adding the solution B into the solution A to obtain a mixed solution of the solution A and the solution B, cooling, carrying out solid-liquid separation on a reaction product to obtain a nano nickel powder filter cake, and washing with water to remove impurities in the filter cake; washing the washed filter cake with absolute ethyl alcohol to remove water; and removing ethanol and trace moisture from the nano nickel powder filter cake washed by absolute ethyl alcohol at the temperature of 40-60 ℃ in vacuum to obtain the spherical nano nickel powder. The method prepares the nano nickel material in the water environment, the specific surface area of the nano nickel is extremely large, and the prepared nano nickel is extremely easy to oxidize because the water contains a large amount of oxygen.

CN101804459A discloses a method for preparing nano nickel powder by using a microchannel reactor, which comprises the steps of preparing a soluble nickel salt alcohol solution and an alkali-containing hydrazine hydrate alcohol solution, injecting the two liquids into a microchannel mixer according to the molar ratio requirement of hydrazine hydrate to nickel for mixing, directly injecting the mixed feed liquid into the microchannel reactor for reaction, and isolating the product from air for preservation after separation and washing respectively. The hydrazine hydrate reduction method for preparing the nano nickel material can generate gas, and the flow of a medium in a micro-channel can be influenced in the micro-channel reactor. Meanwhile, the flux of the microchannel reactor is low, the capacity of mass production is low, and in addition, the produced nickel particles are easy to block the microchannel reactor.

CN1586773A discloses a novel nano-structured nickel powder and its manufacturing method. Uniformly mixing an aqueous solution containing nickel salt and an aqueous solution containing alkali, a reducing agent, an additive A containing two surfactants and sodium dodecyl benzene sulfonate, reacting for 5-390 minutes at 50-98 ℃, cooling, washing and drying to prepare the nano-structure acanthosphere nickel powder with narrow particle size distribution range. The method is to prepare the nano nickel material in the water environment, the shape of the obtained nickel can be controlled by the surfactant, but the nano nickel has large specific surface area and is easy to be oxidized in water.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a preparation method of nano nickel, and the prepared nano nickel has the characteristics of good dispersity, narrow particle size distribution, strong oxidation resistance and the like.

The invention is realized by the following technical scheme: a preparation method of monodisperse antioxidant nano-scale nickel powder comprises the following steps: placing an organic solvent containing nickel salt, an alkaline compound and a surfactant in a closed reaction kettle, reacting for 2-10h at the temperature of 150 ℃ and 250 ℃, and then centrifuging, washing and vacuum drying to obtain monodisperse antioxidant nanoscale nickel powder;

wherein the alkaline compound is one or more of ethylenediamine, octylamine, dodecylamine, hexadecylamine and oleylamine; the organic solvent is one or more of C2-C8 alkyl monohydric alcohol, N-methyl pyrrolidone, phenethyl alcohol and benzyl alcohol.

The method is a simple one-step method for preparing the nano nickel powder, and the energy provided by high temperature endows the system with high reduction activity and high preparation efficiency, so that the method is suitable for preparing the nano nickel on a large scale.

One of the preferable schemes of the invention is that the nickel salt is one or a mixture of more than one of nickel acetate, nickel cyclohexanoate, nickel citrate, nickel acetylacetonate and nickel stearate. These nickel salts are commercially available conventional products and are readily available.

One of the preferable modes of the invention is that the surface active agent is one or a mixture of more than one of PVP and polyacrylamide.

One of the preferable schemes of the invention is that the mass concentration of the nickel salt is 0.5-10%. Too low concentration, too low preparation efficiency, too high concentration and easy agglomeration of particles.

One of the preferable modes of the invention is that the mass ratio of the alkaline compound to the nickel salt is 2-18: 1. The mass ratio is too low, the particles are easy to agglomerate, the mass ratio is too high, and the preparation cost is high.

One of the preferable modes of the invention is that the mass ratio of the surfactant to the nickel salt is 0.02-0.1: 1. Too low or too high a mass ratio, the particles tend to agglomerate.

In order to achieve rapid and effective separation of the nano nickel powder, one of the preferable schemes of the present invention is that the centrifugal rotation speed suggested in the centrifugal step is 2000-8000 rpm.

In order to improve the drying efficiency, one of the preferable schemes of the invention is that the vacuum degree of the vacuum drying step is 0.092-0.097 MPa.

The invention also aims to provide the monodisperse antioxidant nanoscale nickel powder which is obtained by the preparation method and has the characteristics of good dispersity, narrow particle size distribution, strong antioxidant capacity and the like.

The beneficial effects of the invention compared with the prior art comprise:

1) the invention obtains the nano nickel powder with good dispersibility by a one-step method, the obtained nickel powder has narrow particle size distribution (the diameter distance is less than 1.2), grading treatment is not needed, and the system is easy to carry out centrifugal separation and purification.

2) The obtained nano nickel powder is coated with a small amount of organic coating materials on the surface, so that the oxidation resistance of the nano nickel powder can be improved, and the oxygen content is lower than 1.5%.

3) The method has high preparation efficiency and short time consumption, and is suitable for industrial-grade mass preparation of the nano nickel.

Detailed Description

The present invention will be explained below with reference to specific examples, but the present invention is not limited thereto.

Example 1

Adding a certain amount of nickel acetate, oleylamine and PVP into a mixture of octanol and ethanol respectively, wherein the mass concentration of nickel acetate is 0.5%, the mass ratio of oleylamine to nickel acetate is 2:1, the mass ratio of PVP to nickel acetate is 0.02:1, and the mass ratio of octanol to ethanol is 4: 1. And after being uniformly mixed, the mixture is placed in a sealed reaction kettle to react for 4 hours at the temperature of 250 ℃, and the product is centrifuged, washed and dried in vacuum to obtain the nano nickel powder.

Example 2

Adding a certain amount of nickel stearate, nickel acetate, hexadecylamine and PVP into ethanol respectively, wherein the mass ratio of the nickel stearate to the nickel acetate is 1:10, the mass concentration of nickel salt is 10%, the mass ratio of the hexadecylamine to the nickel salt is 10:1, and the mass ratio of the PVP to the nickel salt is 0.1: 1. And after being uniformly mixed, the mixture is placed in a sealed reaction kettle to react for 10 hours at the temperature of 150 ℃, and the product is centrifuged, washed and dried in vacuum to obtain the nano nickel powder.

Example 3

Certain amounts of nickel acetylacetonate, dodecylamine and polyacrylamide are respectively added into N-methylpyrrolidone, wherein the total mass concentration of nickel acetylacetonate is 2.5%, the mass ratio of dodecylamine to nickel compound is 18:1, and the mass ratio of polyacrylamide to nickel acetylacetonate is 0.05: 1. And after being uniformly mixed, the mixture is placed in a sealed reaction kettle to react for 6 hours at the temperature of 220 ℃, and the product is centrifuged, washed and dried in vacuum to obtain the nano nickel powder.

Comparative example 1

Adding a certain amount of nickel stearate, nickel acetate, hexadecylamine and PVP into ethanol respectively, wherein the mass ratio of the nickel stearate to the nickel acetate is 1:10, the mass concentration of nickel salt is 15%, the mass ratio of the hexadecylamine to the nickel salt is 0.2:1, and the mass ratio of the PVP to the nickel salt is 0.1: 1. And after uniformly mixing, placing the mixture in a sealed reaction kettle, reacting for 10 hours at the temperature of 150 ℃, centrifuging, washing and drying the product in vacuum to obtain the nickel powder.

Comparative example 2

Adding a certain amount of nickel sulfate and PVP into an ethanol water solution respectively, wherein the concentration of the nickel sulfate is 10%, the mass ratio of ethanol to water is 1:1, and the mass ratio of PVP to nickel salt is 0.1:1, adding hydrazine hydrate which is 2 times of the mass of the nickel salt into a mixed system, reacting for 4 hours at 80 ℃, centrifuging, washing and drying in vacuum to obtain the nickel powder.

Example 5

The nickel powders obtained in examples 1, 2 and 3 and comparative examples 1 and 2 were subjected to a performance test, and the results were as follows:

TABLE 1 Properties of the materials obtained in the examples and comparative examples

	D50	D90	Radial distance	Oxygen content
					Example 1	41	62	0.97	1.2％
Example 2	302	512	1.12	1.3％
					Example 3	95	141	1.09	0.9％
Comparative example 1	920	2400	2.01	1.5％
					Comparative example 2	2100	6700	2.29	2.3％

The results show that the nano nickel prepared by the invention has the characteristics of good dispersibility, narrow particle size distribution, strong oxidation resistance and the like.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims

1. A preparation method of monodisperse antioxidant nanometer nickel powder is characterized by comprising the following steps: placing an organic solvent containing nickel salt, an alkaline compound and a surfactant in a closed reaction kettle, reacting for 2-10h at the temperature of 150 ℃ and 250 ℃, and then centrifuging, washing and vacuum drying to obtain monodisperse antioxidant nanoscale nickel powder;

wherein the alkaline compound is one or more of ethylenediamine, octylamine, dodecylamine, hexadecylamine and oleylamine; the organic solvent is one or more of C2-C8 alkyl monohydric alcohol, N-methyl pyrrolidone, phenethyl alcohol and benzyl alcohol;

the surfactant is one or a mixture of more than one of PVP and polyacrylamide;

the mass concentration of the nickel salt is 0.5 to 10 percent

The mass ratio of the alkaline compound to the nickel salt is 2-18: 1;

the mass ratio of the surfactant to the nickel salt is 0.02-0.1: 1.

2. The method of claim 1, wherein the nickel salt is one or more of nickel acetate, nickel cyclohexanoate, nickel citrate, nickel acetylacetonate, and nickel stearate.

3. The method for preparing monodisperse antioxidant nanometer nickel powder as claimed in claim 1, wherein the centrifugation rotation speed in the centrifugation step is 2000-.

4. Monodisperse antioxidant nanoscale nickel powder, characterized in that the nickel powder is prepared by the preparation method according to any one of claims 1-3.