Patents by Inventor Han Kwon Chang
Han Kwon Chang 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).
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Patent number: 11362326Abstract: An embodiment of the present invention provides a method for preparing a silicon-carbon-graphene composite, comprising the steps of: (step 1) adding a carbon precursor solution to silicon and performing wet grinding so as to prepare a suspension: (step 2) forming a silicon-carbon composite by spray drying the suspension; and (step 3) spray drying and heat treating a solution comprising the silicon-carbon composite and graphene oxide.Type: GrantFiled: May 23, 2017Date of Patent: June 14, 2022Assignee: Korea Institute of Geoscience and Mineral ResourcesInventors: Hee-Dong Jang, Han-Kwon Chang, Dae-Sup Kil, Ji-Hyuk Choi, Sun-Kyung Kim
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Publication number: 20210242450Abstract: The present disclosure provides a method for manufacturing a silicon-carbon-graphene composite comprising, preparing a suspension in which silicon, carbon source and graphene oxide are dispersed, subjecting the suspension to an aerosol process to form a silicon-carbon source-graphene oxide composite and heat-treating the silicon-carbon source-graphene oxide composite to form a silicon-carbon-graphene composite, and prevents direct contact of the electrolyte, so it can exhibit excellent cycling performance and stability.Type: ApplicationFiled: September 28, 2020Publication date: August 5, 2021Applicant: Korea Institute Of Geoscience And Mineral ResourcesInventors: Hee Dong JANG, Han Kwon CHANG, Sun Kyung KIM
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Patent number: 10822237Abstract: A method for preparing graphene balls, the method including, a) preparing a dispersion which includes, a graphene oxide, a reducing agent ranging from a monosaccharide to a polysaccharide, ammonia water and a dispersion medium; and b) spraying and drying the dispersion. According to the preparation method of the present disclosure, it is possible to prepare uniformly sized and spherical graphene balls. Such graphene can be applied to various fields due to excellent physical and chemical characteristics.Type: GrantFiled: March 14, 2017Date of Patent: November 3, 2020Assignee: Korea Institute Of Geoscience And Mineral ResourcesInventors: Hee-Dong Jang, Han-Kwon Chang, Ji-Hyuk Choi
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Publication number: 20190355985Abstract: An embodiment of the present invention provides a method for preparing a silicon-carbon-graphene composite, comprising the steps of: (step 1) adding a carbon precursor solution to silicon and performing wet grinding so as to prepare a suspension: (step 2) forming a silicon-carbon composite by spray drying the suspension; and (step 3) spray drying and heat treating a solution comprising the silicon-carbon composite and graphene oxide.Type: ApplicationFiled: May 23, 2017Publication date: November 21, 2019Applicant: Korea Institute of Geoscience And Mineral ResourcesInventors: Hee-Dong JANG, Han-Kwon CHANG, Dae-Sup Kil, Ji-Hyuk Choi, Sun-Kyung Kim
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Publication number: 20190112194Abstract: A method for preparing graphene balls, the method including, a) preparing a dispersion which includes, a graphene oxide, a reducing agent ranging from a monosaccharide to a polysaccharide, ammonia water and a dispersion medium; and b) spraying and drying the dispersion. According to the preparation method of the present disclosure, it is possible to prepare uniformly sized and spherical graphene balls. Such graphene can be applied to various fields due to excellent physical and chemical characteristics.Type: ApplicationFiled: March 14, 2017Publication date: April 18, 2019Applicant: Korea Institute Of Geoscience And Mineral ResourcesInventors: Hee-Dong JANG, Han-Kwon CHANG, Ji-Hyuk CHOI
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Patent number: 9296617Abstract: Disclosed is a method for selectively separating and recovering silicon from waste silicon sludge generated during a semiconductor manufacturing process. With the method for separating and recovering silicon from the silicon sludge, oil components, iron, silicon carbide that are included in the silicon sludge may be removed and silicon may be selectively separated and recovered. In addition, silicon may be efficiently recovered without injection of an additive for precipitating a specific component or without a separate device such as a magnetic separator, or the like, for removing iron.Type: GrantFiled: October 17, 2012Date of Patent: March 29, 2016Assignee: Korea Institute of Geoscience and Mineral ResourcesInventors: Hee Dong Jang, Han Kwon Chang, Dae Sup Kil
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Patent number: 9272917Abstract: Disclosed is a method of preparing mesoporous silica particles. The method includes (a) preparing an aqueous silicic acid, (b) spraying the aqueous silicic acid in a droplet state by activating the aqueous silicic acid, and (c) pyrolyzing the sprayed droplet through a reactor, which is previously heated, by allowing the sprayed droplet to pass through the reactor together with a carrier gas. The aqueous silicic acid includes 0.4 M to 0.8 M of silicic acid.Type: GrantFiled: November 14, 2012Date of Patent: March 1, 2016Assignee: KOREA INSTITUTE OF GEOSCIENCE AND MINERAL RESOURCESInventors: Han Kwon Chang, Hee Dong Jang
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Patent number: 8986906Abstract: The present invention provides a method for preparing nanoporous Pt/TiO2 composite particles, nanoporous Pt/TiO2 composite particles prepared by the above preparation method, and a fuel cell comprising the nanoporous Pt/TiO2 composite particles. The nanoporous Pt/TiO2 composite particles according to the present invention have a catalytic effect similar to that of commercially available Pt/carbon black and, thus, can be applied to a fuel cell.Type: GrantFiled: July 14, 2011Date of Patent: March 24, 2015Assignee: Korea Institute of Geoscience and Mineral ResourcesInventors: Hee Dong Jang, Han Kwon Chang, Kuk Cho
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Patent number: 8967492Abstract: A droplet generation system includes a first nozzle configuration structured to receive a liquid and a gas under pressure in a controllable feed ratio, and to merge the liquid and gas to form an intermediate stream that is a mixture of the gas and of a dispersed phase of the liquid. A second nozzle configuration is connected to receive the intermediate stream from the first nozzle configuration and has a valve mechanism with one or more controllable operating parameters to emit a stream of droplets of the liquid. The mean size of the droplets is dependent on the controllable feed ratio of the liquid and gas and the flow rate of the stream of droplets is dependent on the controllable operating parameter(s) of the valve mechanism. A corresponding method is disclosed, as is the application of the system and method to the production of nanoparticles in a thermochemical reactor.Type: GrantFiled: June 30, 2011Date of Patent: March 3, 2015Assignee: Commonwealth Scientific and Industrial Research OrganisationInventors: Jonian Nikolov, Kok Seng Lim, Han Kwon Chang, Hee Dong Jang
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Publication number: 20140339078Abstract: Provided is a glucose sensor. The glucose sensor according to the present invention includes noble metal-graphene composites, and has high sensitivity and significantly excellent current flow as compared to titanium dioxide-graphene composites. In addition, the noble metal-graphene composite manufactured by aerosol spray pyrolysis serves as an improved glucose sensor having desirable sensitivity, stability, reproducibility, and selectivity.Type: ApplicationFiled: September 17, 2013Publication date: November 20, 2014Applicant: KOREA INSTITUTE OF GEOSCIENCE AND MINERAL RESOURCESInventors: Hee Dong JANG, Han Kwon CHANG, Sun Kyung KIM, Ki Min ROH
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Patent number: 8883254Abstract: Disclosed is a method of synthesizing hollow silica having the size of micrometers from sodium silicate. The method includes fabricating a polystyrene organic template from polystyrene latex, (B) cleaning the polystyrene organic template, (C) exchanging media by using a water-base medium, introducing the cleaned polystyrene organic template and sodium silicate, and preparing a silica-coated organic template by performing an acidic hydrolysis reaction, and (D) cleaning the silica-coated organic template included in the water-base medium by using water. The size of the organic template is adjusted by controlling an amount of introduced AIBN included when the organic template is fabricated. The cleaning of the organic template is preferably performed by using water (H2O). The method further includes (B) removing the organic template by using THF and (F) cleaning the hollow silica having no organic template.Type: GrantFiled: November 12, 2013Date of Patent: November 11, 2014Assignee: Korea Institute of Geoscience and Mineral ResourcesInventors: Jiwoong Kim, Hee Dong Jang, Han Kwon Chang
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Publication number: 20140141163Abstract: Disclosed is a method of synthesizing hollow silica having the size of micrometers from sodium silicate. The method includes fabricating a polystyrene organic template from polystyrene latex, (B) cleaning the polystyrene organic template, (C) exchanging media by using a water-base medium, introducing the cleaned polystyrene organic template and sodium silicate, and preparing a silica-coated organic template by performing an acidic hydrolysis reaction, and (D) cleaning the silica-coated organic template included in the water-base medium by using water. The size of the organic template is adjusted by controlling an amount of introduced AIBN included when the organic template is fabricated. The cleaning of the organic template is preferably performed by using water (H2O). The method further includes (B) removing the organic template by using THF and (F) cleaning the hollow silica having no organic template.Type: ApplicationFiled: November 12, 2013Publication date: May 22, 2014Applicant: Korea Institute of Geoscience and Mineral ResourcesInventors: Jiwoong Kim, Hee Dong Jang, Han Kwon Chang
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Publication number: 20140017154Abstract: Disclosed is a method of preparing mesoporous silica particles. The method includes (a) preparing an aqueous silicic acid, (b) spraying the aqueous silicic acid in a droplet state by activating the aqueous silicic acid, and (c) pyrolyzing the sprayed droplet through a reactor, which is previously heated, by allowing the sprayed droplet to pass through the reactor together with a carrier gas. The aqueous silicic acid includes 0.4 M to 0.8 M of silicic acid.Type: ApplicationFiled: November 14, 2012Publication date: January 16, 2014Applicant: KOREA INSTITUTE OF GEOSCIENCE AND MINERAL RESOURCESInventors: Han Kwon Chang, Hee Dong Jang
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Publication number: 20130277201Abstract: Disclosed is a method for selectively separating and recovering silicon from waste silicon sludge generated during a semiconductor manufacturing process. With the method for separating and recovering silicon from the silicon sludge, oil components, iron, silicon carbide that are included in the silicon sludge may be removed and silicon may be selectively separated and recovered. In addition, silicon may be efficiently recovered without injection of an additive for precipitating a specific component or without a separate device such as a magnetic separator, or the like, for removing iron.Type: ApplicationFiled: October 17, 2012Publication date: October 24, 2013Inventors: Hee Dong Jang, Han Kwon Chang, Dae Sup Kil
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Patent number: 8562815Abstract: Provided is a glucose sensor including a titanium dioxide-graphene composite having a porous structure. More particularly, the glucose sensor includes a working electrode having the titanium dioxide-graphene composite having the porous structure and an enzyme to provide features that allow a current flow to be excellent, a current to be sensitively changed depending on a change in electric potential, sensitivity to be high, and a low voltage characteristic to be excellent.Type: GrantFiled: October 27, 2011Date of Patent: October 22, 2013Assignee: Korea Institute of Geoscience and Mineral ResourcesInventors: Hee-Dong Jang, Han-Kwon Chang, Sun-Kyung Kim
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Publication number: 20130101500Abstract: A droplet generation system includes a first nozzle configuration structured to receive a liquid and a gas under pressure in a controllable feed ratio, and to merge the liquid and gas to form an intermediate stream that is a mixture of the gas and of a dispersed phase of the liquid. A second nozzle configuration is connected to receive the intermediate stream from the first nozzle configuration and has a valve mechanism with one or more controllable operating parameters to emit a stream of droplets of the liquid. The mean size of the droplets is dependent on the controllable feed ratio of the liquid and gas and the flow rate of the stream of droplets is dependent on the controllable operating parameter(s) of the valve mechanism. A corresponding method is disclosed, as is the application of the system and method to the production of nanoparticles in a thermochemical reactor.Type: ApplicationFiled: June 30, 2011Publication date: April 25, 2013Applicants: KOREA INSTITUTE OF GEOSCIENCE AND MINERAL RESOURCES, COMMONWEALTH SCIENTIFIC AND INDUSTRIAL RESEARCH ORGANISATIONInventors: Jonian Nikolov, Kok Seng Lim, Han Kwon Chang, Hee Dong Jang
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Publication number: 20130062201Abstract: Provided is a glucose sensor including a titanium dioxide-graphene composite having a porous structure. More particularly, the glucose sensor includes a working electrode having the titanium dioxide-graphene composite having the porous structure and an enzyme to provide features that allow a current flow to be excellent, a current to be sensitively changed depending on a change in electric potential, sensitivity to be high, and a low voltage characteristic to be excellent.Type: ApplicationFiled: October 27, 2011Publication date: March 14, 2013Applicant: Korea Institute of Geoscience and Mineral ResourcesInventors: Hee-Dong Jang, Han-Kwon Chang, Sun-Kyung Kim
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Publication number: 20120219882Abstract: The present invention provides a method for preparing nanoporous Pt/TiO2 composite particles, nanoporous Pt/TiO2 composite particles prepared by the above preparation method, and a fuel cell comprising the nanoporous Pt/TiO2 composite particles. The nanoporous Pt/TiO2 composite particles according to the present invention have a catalytic effect similar to that of commercially available Pt/carbon black and, thus, can be applied to a fuel cell.Type: ApplicationFiled: July 14, 2011Publication date: August 30, 2012Inventors: Hee Dong Jang, Han Kwon Chang, Kuk Cho
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Patent number: 8187562Abstract: Disclosed is a method for producing a cerium dioxide nanopowder by flame spray pyrolysis. The method comprises dissolving a cerium compound in an organic solvent to prepare a precursor solution, atomizing the precursor solution into microdroplets using an ultrasonic atomizer, transferring the microdroplets together with an argon gas as a carrier gas to a central portion of a high-temperature diffusion flame burner, subjecting the microdroplets to pyrolysis and oxidation in the central portion of the diffusion flame burner to produce a cerium dioxide nanopowder, and collecting the cerium dioxide nanopowder using a collector. According to the method, a cerium dioxide nanopowder can be continuously produced on a large scale by flame spray pyrolysis. In addition, the particle size and uniformity of the cerium dioxide nanopowder can be controlled by appropriately selecting the kind of the solvent and the concentration of the raw material.Type: GrantFiled: November 24, 2010Date of Patent: May 29, 2012Assignee: Korea Institute of Geoscience and Mineral Resources (KIGAM)Inventors: Han Kwon Chang, Hee Dong Jang, Dae Sup Kil, Kuk Cho, Sung-Wook Cho
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Publication number: 20120046159Abstract: Disclosed is a method for recovering cobalt and manganese from a spent cobalt-manganese-bromine (CMB) catalyst. The method includes (a) continuously leaching a spent CMB catalyst with sulfuric acid, (b) separating the leachate into a solution and a residue, (c) extracting the solution with a solvent, and (d) washing the extract with water. According to the method, high-purity cobalt and manganese can be recovered in high yield from a spent CMB catalyst while minimizing the amount of impurities. Further disclosed is a method for producing a CMB liquid catalyst from the extract containing cobalt and manganese obtained by the recovery method.Type: ApplicationFiled: August 16, 2011Publication date: February 23, 2012Inventors: Shun Myung SHIN, Sung Ho Ju, Jin Gu Kang, Han Kwon Chang, Jeong Soo Sohn