Patents by Inventor Yoshitomo Ozaki

Yoshitomo Ozaki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11214849
    Abstract: A method for recovering scandium, by which scandium is able to be recovered from nickel oxide ore. The present invention comprises: a leaching step S1 for obtaining a leachate by leaching a nickel oxide ore containing scandium with use of sulfuric acid; a neutralization step by adding a neutralizing agent thereto; a sulfurization step by adding a sulfurizing agent to the post-neutralization solution; an ion exchange step by bringing the post-sulfurization solution into contact with a chelating resin; a dissolution step by obtaining a precipitate of scandium hydroxide by adding an alkali into the scandium eluent, and subsequently adding an acid solution to the scandium hydroxide; a solvent extraction step by bringing the scandium acid dissolution liquid into contact with a neutral extractant; and a scandium recovery step by adding oxalic acid to the extraction residue and subsequently roasting the salt of scandium oxalate.
    Type: Grant
    Filed: February 21, 2017
    Date of Patent: January 4, 2022
    Assignee: SUMITOMO METAL MINING CO., LTD.
    Inventors: Hidemasa Nagai, Keiji Kudo, Itsumi Matsuoka, Yoshitomo Ozaki, Hirofumi Shoji, Shin-ya Matsumoto, Tatsuya Higaki
  • Publication number: 20210254193
    Abstract: A method for recovering scandium, by which scandium is able to be recovered from nickel oxide ore. The present invention comprises: a leaching step S1 for obtaining a leachate by leaching a nickel oxide ore containing scandium with use of sulfuric acid; a neutralization step by adding a neutralizing agent thereto; a sulfurization step by adding a sulfurizing agent to the post-neutralization solution; an ion exchange step by bringing the post-sulfurization solution into contact with a chelating resin; a dissolution step by obtaining a precipitate of scandium hydroxide by adding an alkali into the scandium eluent, and subsequently adding an acid solution to the scandium hydroxide; a solvent extraction step by bringing the scandium acid dissolution liquid into contact with a neutral extractant; and a scandium recovery step by adding oxalic acid to the extraction residue and subsequently roasting the salt of scandium oxalate.
    Type: Application
    Filed: February 21, 2017
    Publication date: August 19, 2021
    Inventors: Hidemasa Nagai, Keiji Kudo, Itsumi Matsuoka, Yoshitomo Ozaki, Hirofumi Shoji, Shin-ya Matsumoto, Tatsuya Higaki
  • Publication number: 20210197266
    Abstract: Provided is a method for controlling generation of scaling in a reaction vessel to reduce time and cost required for removal of the scaling in the process of producing nickel powder from a solution containing a nickel ammine sulfate complex. This is a method for producing nickel powder, including: adding, to the solution containing the nickel ammine sulfate complex, seed crystals in an amount of 0.3 times or more and 3 times or less the weight of nickel in the solution to form a slurry; and blowing hydrogen gas into the slurry to reduce a nickel complex ion and to thereby form a nickel precipitate.
    Type: Application
    Filed: February 8, 2017
    Publication date: July 1, 2021
    Inventors: Shin-ichi Heguri, Yoshitomo Ozaki, Osamu Ikeda, Yohei Kudo
  • Publication number: 20200384542
    Abstract: Provided is a nickel powder manufacturing method capable of efficiently manufacturing a high-quality nickel powder using as little ammonium gas or ammonium water as possible. The nickel powder manufacturing method according to the present invention is characterized by comprising: a first step for generating a post-neutralization slurry including nickel hydroxide by mixing a nickel sulfate aqueous solution and a neutralizing agent; a second step for causing a complex-forming reaction by mixing an ammonium sulfate aqueous solution with the post-neutralization slurry and obtaining a post-complexation slurry including a nickel ammine complex aqueous solution; and a reducing step for obtaining a nickel powder and a post-reduction solution by contacting hydrogen gas with the nickel ammine complex aqueous solution. Further, it is preferable that a post-complexation solution obtained in the reduction step be repeatedly used as the ammonium sulfate aqueous solution to be added to the post-neutralization slurry.
    Type: Application
    Filed: September 4, 2017
    Publication date: December 10, 2020
    Applicant: Sumitomo Metal Mining Co., Ltd.
    Inventors: Kazuyuki TAKAISHI, Yoshitomo OZAKI, Shin-ichi HEGURI, Ryo-ma YAMAGUMA, Yasuo DOI
  • Publication number: 20200338641
    Abstract: Provided is a production method for maintaining the quality while keeping a high operating rate of the reaction by continuously feeding a solution, seed crystals, and hydrogen gas into a reactor to produce nickel powder, and continuously discharging the resulting powder. The method for producing nickel powder comprises feeding a nickel ammine sulfate complex solution and seed crystals into a reactor, and feeding hydrogen gas into the reactor to subject a nickel complex ion in the nickel ammine sulfate complex solution to a reduction treatment and to thereby produce nickel powder, wherein, in the reduction treatment, while the nickel ammine sulfate complex solution is being continuously fed into the reactor, a temperature inside the reactor is controlled within the range of 150 to 185° C. and the feed rate of hydrogen gas is controlled to maintain an inner pressure of the reactor in the range of 2.5 to 3.5 MPa.
    Type: Application
    Filed: March 3, 2017
    Publication date: October 29, 2020
    Applicant: Sumitomo Metal Mining Co., Ltd.
    Inventors: Yoshitomo OZAKI, Shin-ichi HEGURI, Kazuyuki TAKAISHI, Ryo-ma YAMAGUMA
  • Patent number: 10766072
    Abstract: Provided is a method for producing high density nickel powder particularly having a median diameter of 100 to 160 ?m 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 ?m and a bulk density of 1 to 4.5 g/cm3.
    Type: Grant
    Filed: October 25, 2016
    Date of Patent: September 8, 2020
    Assignee: SUMITOMO METAL MINING CO., LTD.
    Inventors: Hideki Ohara, Yoshitomo Ozaki, Shin-ichi Heguri, Kazuyuki Takaishi, Osamu Ikeda, Tomoaki Yoneyama, Yohei Kudo
  • Patent number: 10549351
    Abstract: A method for producing nickel powder sequentially includes: a mixing step of adding, to a nickel ammine sulfate complex solution, an insoluble solid as seed crystals and a polyacrylate or lignosulfonate as a dispersant to form a mixed slurry; and a reduction and precipitation step of charging a reaction vessel with the mixed slurry and blowing hydrogen gas into the mixed slurry in the reaction vessel to reduce nickel complex ions in the mixed slurry to form nickel precipitate on the surface of the insoluble solid, wherein the amount of the dispersant added in the mixing step is controlled to control the number of the nickel powder obtained by formation of the nickel precipitate in the reduction and precipitation step.
    Type: Grant
    Filed: March 26, 2015
    Date of Patent: February 4, 2020
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Shin-ichi Heguri, Yoshitomo Ozaki, Kazuyuki Takaishi, Tomoaki Yoneyama, Hideki Ohara, Osamu Ikeda, Yohei Kudo
  • Patent number: 10518332
    Abstract: A nickel sulfate amine complex liquid and nickel powder having a particle diameter of 0.1 ?m to 300 ?m are supplied to a reaction container, hydrogen gas is continuously supplied while the inside of the reaction container is maintained at 150° C. to 250° C., and the pressure is set to 2.5 MPa to 3.5 MPa, whereby nickel ions in the nickel sulfate amine complex liquid are reduced to nickel and deposited on the surfaces of the nickel powder supplied to the reaction container, a reacted slurry including the nickel sulfate amine complex liquid and the nickel powder is then transferred to a pressurized storage container at the same or slightly lower pressure than the internal pressure of the reaction container, and the pressure of the pressurized storage container to which the reacted slurry is transferred is then reduced, after which the reacted slurry is extracted from the pressurized storage container.
    Type: Grant
    Filed: May 30, 2017
    Date of Patent: December 31, 2019
    Assignee: SUMITOMO METAL MINING CO., LTD.
    Inventors: Kazuyuki Takaishi, Shin-ichi Heguri, Ryo-ma Yamaguma, Yoshitomo Ozaki, Yasuo Doi
  • Patent number: 10500644
    Abstract: Provided a production method for reducing the content level of sulfur and carbon which are impurities in nickel powder to improve the quality of nickel powder produced by a complexing reduction method. The method of producing nickel powder having low carbon and sulfur concentrations includes: a complexing treatment of adding a complexing agent to a nickel sulfate aqueous solution to form a solution containing nickel complex ions; maintaining the solution containing nickel complex ions at a solution temperature of 150 to 250° C. in a pressure vessel and blowing hydrogen gas into the solution containing nickel complex ions to perform hydrogen reduction to produce nickel powder; washing the nickel powder with water; and then roasting the nickel powder washed with water in a mixed gas atmosphere of nitrogen and hydrogen.
    Type: Grant
    Filed: April 13, 2015
    Date of Patent: December 10, 2019
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Yoshitomo Ozaki, Shin-ichi Heguri, Kazuyuki Takaishi, Osamu Ikeda, Hideki Ohara, Tomoaki Yoneyama, Yohei Kudo
  • Publication number: 20190308249
    Abstract: Provided is a method with which it is possible to prevent equipment, such as piping and valves, used to discharge and recover a nickel powder-containing slurry from a high pressure reaction tank from being damaged and trapping the nickel powder therein and to enable continuous operation, thereby improving the productivity. This nickel powder production method comprises a step of reacting a nickel sulfate-amine complex solution with hydrogen gas under high pressure in a reaction tank, thereby obtaining a nickel powder slurry containing nickel powder. The method is characterized in that the nickel powder slurry is discharged and transferred through discharge piping from the reaction tank in which the nickel powder-containing slurry has been produced, and then a washing solution is supplied to the discharge piping at a predetermined pressure to wash the discharge piping.
    Type: Application
    Filed: June 14, 2017
    Publication date: October 10, 2019
    Applicant: SUMITOMO METAL MINING CO., LTD.
    Inventors: Kazuyuki Takaishi, Yoshitomo Ozaki, Shin-ichi Heguri
  • Patent number: 10434577
    Abstract: Provided is nickel powder obtained by adding seed crystals to a nickel ammine complex solution and performing hydrogen reduction reaction under high temperatures and high pressures, wherein the nickel powder does not produce dust during handling, and a container can be efficiently filled with the nickel powder. The method for producing nickel powder includes: adding seed crystals and a surfactant having a nonionic or anionic functional group to a solution containing a nickel ammine complex to forma mixed slurry; and subjecting the mixed slurry to hydrogen reduction under high temperature and high pressure conditions in a pressure vessel to obtain nickel powder from the mixed slurry.
    Type: Grant
    Filed: March 24, 2015
    Date of Patent: October 8, 2019
    Assignees: KOCHI UNIVERSITY, NATIONAL UNIVERSITY CORPORATION, SUMITOMO METAL MINING CO., LTD.
    Inventors: Kazumichi Yanagisawa, Junhao Zhang, Kazuyuki Takaishi, Tomoaki Yoneyama, Shin-ichi Heguri, Hideki Ohara, Osamu Ikeda, Yohei Kudo, Yoshitomo Ozaki
  • Publication number: 20190210114
    Abstract: A nickel sulfate amine complex liquid and nickel powder having a particle diameter of 0.1 ?m to 300 ?m are supplied to a reaction container, hydrogen gas is continuously supplied while the inside of the reaction container is maintained at 150° C. to 250° C., and the pressure is set to 2.5 MPa to 3.5 MPa, whereby nickel ions in the nickel sulfate amine complex liquid are reduced to nickel and deposited on the surfaces of the nickel powder supplied to the reaction container, a reacted slurry including the nickel sulfate amine complex liquid and the nickel powder is then transferred to a pressurized storage container at the same or slightly lower pressure than the internal pressure of the reaction container, and the pressure of the pressurized storage container to which the reacted slurry is transferred is then reduced, after which the reacted slurry is extracted from the pressurized storage container.
    Type: Application
    Filed: May 30, 2017
    Publication date: July 11, 2019
    Applicant: SUMITOMO METAL MINING CO., LTD.
    Inventors: Kazuyuki Takaishi, Shin-ichi Heguri, Ryo-ma Yamaguma, Yoshitomo Ozaki, Yasuo Doi
  • Patent number: 10227675
    Abstract: A wet smelting method for nickel oxide ores from which nickel, cobalt, etc. are recovered is provided with which it is possible to reduce the consumption of an acid in leaching, such as sulfuric acid, and to recover valuable metals. The method comprises: step (A) in which nickel oxide ores as a raw material are separated into a limonite-type ore having a low magnesium content and a saprolite-type ore having a high magnesium content; step (B) in which the saprolite-type ore is subjected to normal-pressure leaching under given standardized leaching conditions using the pressure leachate obtained by pressure leaching in step (C); and step (C) in which the limonite-type ore obtained in step (A) is mixed with the normal-pressure leaching residue obtained in step (B) and the mixture is reacted with sulfuric acid in an acidic atmosphere having a high temperature and a high pressure, thereby conducting pressure leaching.
    Type: Grant
    Filed: December 8, 2015
    Date of Patent: March 12, 2019
    Assignee: SUMITOMO METAL MINING CO., LTD.
    Inventors: Hirofumi Shouji, Keiji Kudo, Yoshitomo Ozaki, Hiroshi Kobayashi, Satoshi Asano
  • Patent number: 10220446
    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 comprises: a mixing step of adding, to a solution containing a nickel ammine sulfate complex, 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.
    Type: Grant
    Filed: February 17, 2015
    Date of Patent: March 5, 2019
    Assignee: 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
  • Publication number: 20190061006
    Abstract: Provided is a method for producing seed crystals of cobalt powder, sequentially including: a complexing step of adding ammonia, an ammonia compound solution, or both of ammonia and an ammonia compound solution to a cobalt sulfate solution to obtain a solution containing a cobalt ammine sulfate complex; a mixing step of adding a solid to the solution containing the cobalt ammine sulfate complex to form a mixture slurry; a reduction and precipitation step of charging a reaction vessel with the mixture slurry, blowing hydrogen gas into the reaction vessel and reducing cobalt contained in the mixture slurry to obtain a cobalt powder slurry containing cobalt precipitate with a cobalt component precipitated on the surface of the solid as cobalt powder; and a solid-liquid separation step of performing solid-liquid separation on the cobalt powder slurry to obtain cobalt precipitate and a solution after reduction.
    Type: Application
    Filed: October 17, 2016
    Publication date: February 28, 2019
    Inventors: Osamu Ikeda, Ryo-ma Yamaguma, Yoshitomo Ozaki, Kazuyuki Takaishi, Shin-ichi Heguri, Yohei Kudo, Yasuo Doi
  • Publication number: 20190054541
    Abstract: Provided is a method for producing high density nickel powder particularly having a median diameter of 100 to 160 ?m 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 ?m and a bulk density of 1 to 4.5 g/cm3.
    Type: Application
    Filed: October 25, 2016
    Publication date: February 21, 2019
    Inventors: Hideki Ohara, Yoshitomo Ozaki, Shin-ichi Heguri, Kazuyuki Takaishi, Osamu Ikeda, Tomoaki Yoneyama, Yohei Kudo
  • Publication number: 20190047052
    Abstract: Provided is a method for producing coarse particles of high purity nickel powder from a nickel ammine sulfate complex solution using industrially-inexpensive hydrogen gas and fine nickel powder. The method for producing nickel powder, including performing the following processes (1) to (5), wherein a sulfuric acid solution containing nickel and cobalt is subjected to (1) a pH adjusting step, (2) a solvent extraction step, (3) a complexing step for obtaining a nickel ammine sulfate complex solution, (4) a reduction step for obtaining a reduced slurry containing nickel powder, and (5) a solid-liquid separation step of performing solid-liquid separation to obtain nickel powder and a solution after reduction, and solution after reduction repeatedly using the solution after reduction in either or both of (2) the solvent extraction step and (3) the complexing step.
    Type: Application
    Filed: February 15, 2017
    Publication date: February 14, 2019
    Inventors: Shin-ichi HEGURI, Yoshitomo OZAKI
  • Patent number: 10190189
    Abstract: The purpose of the present invention is to recover roughly purified scandium, which is purified to an extent acceptable for a technique for highly purifying scandium, efficiently and without any complicated operation from a neutralization sediment (drainage sediment) generated in neutralizing acid mine drainage which contains a sulfur component. This scandium recovery process includes a washing step (S1) for washing a neutralization sediment (drainage sediment) and a dissolution step (S2) for subjecting the washed sediment obtained in the washing step (S1) to dissolution in an acid. It is preferable that the process further includes a re-dissolution step (S3) for subjecting a dissolution residue which remains after the dissolution in the dissolution step (S2) to dissolution with an acid. In the washing step (S1), the neutralization sediment is washed with a washing liquid until the pH of the post-washing liquid generated in the washing step becomes 6 or higher.
    Type: Grant
    Filed: February 18, 2015
    Date of Patent: January 29, 2019
    Assignee: SUMITOMO METAL MINING CO., LTD.
    Inventors: Toshihiko Nagakura, Yoshitomo Ozaki, Hidemasa Nagai, Tatsuya Higaki
  • Publication number: 20190009343
    Abstract: Provided is a method for producing nickel powder, wherein fine nickel powder serving as seed crystals needed for production of nickel powder is produced from a solution containing a nickel ammine sulfate complex according to the amount needed for the production of the nickel powder. The method for producing nickel powder is characterized in that: the solution containing the nickel ammine sulfate complex, an insoluble solid, and a dispersant are continuously fed into a reaction vessel, followed by stirring to prepare a solution containing a nickel complex ion; hydrogen gas is blown into the prepared solution to reduce the nickel complex ion in the solution containing the nickel complex ion, thereby forming a precipitate of nickel particles on the surface of the insoluble solid; and thereafter the post-reduction solution is extracted from the reaction vessel.
    Type: Application
    Filed: February 22, 2017
    Publication date: January 10, 2019
    Inventors: Shin-ichi Heguri, Yoshitomo Ozaki, Ryo-ma Yamaguma
  • Patent number: 10118224
    Abstract: Provided is a method for producing nickel powder from a nickel ammine sulfate complex solution, comprising treatment steps of: (1) a seed crystal production step of producing nickel powder having an average particle size of 0.1 to 5 ?m; (2) a seed crystal addition step of adding the nickel powder obtained in the step (1) as seed crystals to form a mixed slurry; (3) a reduction step of forming a reduced slurry containing nickel powder formed by precipitation of a nickel component in the mixed slurry on the seed crystals; and (4) a growth step of performing solid-liquid separation to separate and recover the nickel powder as a solid phase component and then blowing hydrogen gas into a solution prepared by adding the nickel ammine sulfate complex solution to the recovered nickel powder to grow the nickel powder to form high purity nickel powder.
    Type: Grant
    Filed: January 27, 2015
    Date of Patent: November 6, 2018
    Assignees: KOCHI UNIVERSITY, NATIONAL UNIVERSITY CORPORATION, SUMITOMO METAL MINING CO., LTD.
    Inventors: Kazumichi Yanagisawa, Junhao Zhang, Shin-ichi Heguri, Hideki Ohara, Osamu Ikeda, Tomoaki Yoneyama, Yohei Kudo, Yoshitomo Ozaki