Method for producing high density nickel powder

Patent metadata

Field	Value
Publication number	US-10766072-B2
Application number	US-201615770523-A
Country	US
Kind code	B2
Filing date	Oct 25, 2016
Priority date	Oct 26, 2015
Publication date	Sep 8, 2020
Grant date	Sep 8, 2020

Abstract

Provided is a method for producing high density nickel powder particularly having a median diameter of 100 to 160 μm by controlling a particle size of nickel powder. The method includes: performing an initial operation by charging a pressure vessel equipped with a stirrer with a nickel ammine complex solution containing nickel in the concentration of 5 to 75 g/L together with seed crystals in the amount of 5 to 200 g per liter of the solution, increasing the temperature of the solution, and performing a reduction reaction with hydrogen by blowing hydrogen gas into the pressure vessel, thereby obtaining the nickel contained in the nickel ammine complex solution as nickel powder; and thereafter, performing a specified operation A repeatedly at least once to obtain the nickel powder having the median diameter of 100 to 160 μm and a bulk density of 1 to 4.5 g/cm3.

First claim

The invention claimed is:

1. A method of producing nickel powder, comprising:
performing an initial operation by charging a pressure vessel equipped with a stirrer with a nickel ammine complex solution containing nickel in a concentration of 5 to 75 g/L together with seed crystals in an amount of 5 g to 200 g per liter of the complex solution, increasing a temperature of the solution, and blowing hydrogen gas into the pressure vessel for performing a reduction reaction with hydrogen, thereby obtaining the nickel contained in the nickel ammine complex solution as nickel powder; and thereafter
performing an operation A repeatedly, the operation A including:
putting the obtained nickel powder in a cylinder filled with water;
stirring the nickel powder and the water in the cylinder;
allowing the cylinder to stand still in an upright position;
recovering from an upper portion of the cylinder a part of the obtained nickel powder; and
charging the pressure vessel equipped with the stirrer with the recovered nickel powder used as the seed crystals together with the nickel ammine complex solution in an amount of 5 g to 200 g per liter of the nickel ammine complex solution containing nickel in the concentration of 5 to 75 g/L, increasing a temperature of the solution, and performing the reduction reaction with hydrogen by blowing hydrogen gas into the pressure vessel for obtaining nickel powder,

to obtain the nickel powder having a median diameter of 100 μm or more and 160 μm or less, and having a bulk density of 1 to 4.5 g/cm 3 .

2. The method of producing nickel powder according to claim 1 , wherein the operation A is repeated four times or more and thus the reduction reaction is performed five times or more in total including the initial operation to obtain the nickel powder.

Assignees

• Sumitomo Metal Mining Co

Inventors

• Ohara Hideki
• Ozaki Yoshitomo
• HEGURI Shin-ichi
• Takaishi Kazuyuki
• Ikeda Osamu
• Yoneyama Tomoaki
• Kudo Yohei

Classifications

• B22F9/22 Primary

  using gaseous reductors · CPC title

• B22F1/05

  Metallic powder characterised by the size or surface area of the particles · CPC title

• H01B5/00

  Non-insulated conductors or conductive bodies characterised by their form · CPC title

• B22F9/24

  starting from liquid metal compounds, e.g. solutions · CPC title

• B22F9/26 Primary

  using gaseous reductors · CPC title