# US 2016/0354844 A1 · Method for producing nickel powder

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- Number: US 2016/0354844 A1
- Document ID: US20160354844A1
- Status: Published application
- Kind: A1
- Application number: 15/117,855
- Filed: 2015-02-17
- Published: 2016-12-08
- Earliest claimed: 2014-02-17
- Assignees: Kochi University, National University Corporation; Sumitomo Metal Mining Co., Ltd.
- Applicants: Kochi University, National University Corporation; Sumitomo Metal Mining Co., Ltd.
- Inventors: Kazumichi Yanagisawa; Junhao Zhang; Shin-ichi Heguri; Yoshitomo Ozaki; Kazuyuki Takaishi; Hideki Ohara; Tomoaki Yoneyama; Osamu Ikeda; Yohei Kudo
- Web page: https://patentgrep.com/patent/US20160354844A1

## CPC

- B22F 9/24: starting from liquid metal compounds, e.g. solutions
- B22F 9/26: using gaseous reductors
- B22F 2009/245: {Reduction reaction in an Ionic Liquid [IL]}
- B22F 2301/15: Nickel or cobalt
- B22F 2998/10: Processes characterised by the sequence of their steps
- B22F 2999/00: Aspects linked to processes or compositions used in powder metallurgy
- Y02P 10/20: Recycling
- B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

Provided is a method for producing fine nickel powder used as suitable seed crystals for producing nickel powder from a solution containing a nickel ammine sulfate complex. The method for producing nickel powder sequentially includes: a mixing step of adding, to a solution containing a nickel ammine sulfate complex, a dispersant containing a sulfonate and an insoluble solid which is insoluble in the solution to form a mixed slurry; a reduction and precipitation step of charging a reaction vessel with the mixed slurry and then blowing hydrogen gas into the mixed slurry in the reaction vessel to reduce nickel complex ions contained in the mixed slurry to form nickel precipitate on a surface of the insoluble solid; and a separation step of separating the nickel precipitate on the surface of the insoluble solid from the surface of the insoluble solid to form nickel powder.

## Claims

### Claim 1

A method for producing nickel powder, sequentially comprising:
a mixing step of adding, to a solution containing a nickel ammine sulfate complex, a dispersant containing a sulfonate and an insoluble solid which is insoluble in the solution to form a mixed slurry;
a reduction and precipitation step of charging a reaction vessel with the mixed slurry and then blowing hydrogen gas into the mixed slurry while maintaining a pressure of a gas phase part in the reaction vessel at 1.0 to 4.0 MPa, to reduce nickel complex ions contained in the mixed slurry to form nickel precipitate on a surface of the insoluble solid; and
a separation step of separating the nickel precipitate on the surface of the insoluble solid from the surface of the insoluble solid to form nickel powder.

### Claim 2 (depends on 1)

The method for producing nickel powder according to claim 1, wherein the concentration of ammonium sulfate contained in the solution containing a nickel ammine sulfate complex is in the range of 10 to 500 g/L.

### Claim 3 (depends on 2)

The method for producing nickel powder according to claim 2, wherein, in the reduction step, the mixed slurry when the hydrogen gas is blown has a temperature of 150 to 200° C.

### Claim 4

(canceled)

### Claim 5 (depends on 3)

The method for producing nickel powder according to claim 3, wherein the insoluble solid is one or a combination selected from among nickel, alumina, zirconia, iron, and silica.

### Claim 6 (depends on 5)

The method for producing nickel powder according to claim 5, wherein, in the mixing step, the dispersant containing a sulfonate is added before the insoluble solid is added.

### Claim 7 (depends on 1)

The method for producing nickel powder according to claim 1, wherein, in the reduction step, the mixed slurry when the hydrogen gas is blown has a temperature of 150 to 200° C.

### Claim 8 (depends on 7)

The method for producing nickel powder according to claim 7, wherein the insoluble solid is one or a combination selected from among nickel, alumina, zirconia, iron, and silica.

### Claim 9 (depends on 8)

The method for producing nickel powder according to claim 8, wherein, in the mixing step, the dispersant containing a sulfonate is added before the insoluble solid is added.

### Claim 10 (depends on 1)

The method for producing nickel powder according to claim 1, wherein the insoluble solid is one or a combination selected from among nickel, alumina, zirconia, iron, and silica.

### Claim 11 (depends on 10)

The method for producing nickel powder according to claim 10, wherein, in the mixing step, the dispersant containing a sulfonate is added before the insoluble solid is added.

### Claim 12 (depends on 1)

The method for producing nickel powder according to claim 1, wherein, in the mixing step, the dispersant containing a sulfonate is added before the insoluble solid is added.