Presentations -
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紫外線と過酸化水素によるホルムアデヒドの分解
菅原悠人,加藤貴宏,大川浩一,菅原勝康
第19回先端研究発表会 (東北大学工学部) 2017.05 - 2017.05 化学工学会東北支部・宮城化学工学懇話会
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AKAZAWA Nobuyuki, OKAWA Hirokazu, Kamal Wan Mohamad Ikhwan Bin Wan, KATO Takahiro, SUGAWARA Katsuyasu
Proceedings of Conference on Coal Science 2017 - 2017 The Japan Institute of Energy
<p>Desulfurization of bitumen was performed by combination of oxidative desulfurization (ODS) and ultrasound irradiation. Tetrahydrofuran (THF) was employed as solvent to emulsify the bitumen and improve the desulfurization ratio. In the result, the desulfurization ratio reached to 82.7% (ion-exchange water: 52%). We also investigated simultaneous recovery and desulfurization of bitumen from oil sand using ODS and ultrasound. Recovery ratio of bitumen from oil sand was 68.1% and the purity of recovered bitumen was 72.3%.</p>
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No.1-7 Characteristics and Self-heating Behavior of Moatize Coals, Moatize Coal Basin, Mozambique
UACIQUETE Dorcas L. E., KATO Takahiro, OKAWA Hirokazu, SUGAWARA Katsuyasu
石炭科学会議発表論文集 2017 - 2017 一般社団法人 日本エネルギー学会
<p>Mozambique has a great potential in terms of coal deposits, the most important is Moatize Coal Basin (MCB) located in Tete Province, Moatize district. The MCB has estimates reserves of about 2.5 billion tons, with thick coal seams allowing the open-pit exploitation. It is well known throughout the world that Moatize basin is a world class deposit for coking and thermal. However, recently, occurrences of spontaneous combustion are being resisted in both in situ coal seams and stockpiles of washed products (coking coal and thermal coal). Spontaneous combustion is a direct result of self-heating and it is a global issue affecting environment, economy and human health.</p><p>In this study, petrographic and chemical properties of samples of raw coal (<i>in situ layers</i>), coking coal and thermal coal were studied using image analysis through oil immersion microscopy and elemental and proximate analyzers (CHN, CS and TGA-DTA) respectively, to predict the propensity of self-heating. The microscopic characterization revealed important features such as changes in vitrinite reflectance, oxidation rims, micropores and cracks mainly on in situ coal and some signs of weathering and oxidation on thermal coal which are related to their reactivity and potential to self-heating leading later to spontaneous combustion</p>
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No.2-15 Arsenic Removal from Denitration Catalyst by Carbon Reduction
KATO Takahiro, SATO Yukiko, OKAWA Hirokazu, SUGAWARA Katsuyasu
Proceedings of Conference on Coal Science 2017 - 2017 The Japan Institute of Energy
<p>Decreasing of activity of the denitration catalyst caused by arsenic adsorption is one of the big problems against the stable long term operation of the coal power plant. In order to remove arsenic from the catalyst by conversion of As<sub>2</sub>O<sub>5</sub> to volatile As<sub>2</sub>O<sub>3</sub>, methanol was used as the carbon source for the reduction. Effects of treatment temperature, reaction time and partial pressure of methanol on changes in the removal extent of arsenic, the chemical forms of vanadium and the denitration activity were investigated.</p>
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No.1-15 Recovery of Rare Metals from Spent Denitrification Catalyst
SAKUSABE Kosuke, KATO Takahiro, OKAWA Hirokazu, SUGAWARA Katsuyasu
Proceedings of Conference on Coal Science 2017 - 2017 The Japan Institute of Energy
<p>Selective recovery process of titanium, vanadium and tungsten has been developed for the spent denitrification catalyst produced from coal fired plant. Volatilization behaviors of the rare metals were followed in a chlorine gas stream with the addition of carbon as a reducing agent. Methanol vapor was supplied to a fixed bed of catalyst at 400 °C and fine carbon was deposited on the surface of catalyst. The volatilization rates of the rare metals ware enhanced drastically with the use of the deposited carbon compared to pyrolytic carbon prepared from phenolphthalein. The rare metals in the catalyst could be recovered selectively at 400 °C without silicon, iron and aluminum when the deposited carbon of 20 wt% was used.</p>
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No.1-11 Oxidative desulfurization of Hyper-coal using hydrogen peroxide and acetic anhydride
ONODERA Gai, KATO Takahiro, OKAWA Hirokazu, SUGAWARA Katuyasu
Proceedings of Conference on Coal Science 2017 - 2017 The Japan Institute of Energy
<p>To develop a mild chemical desulfurization method without residual chemicals in the treated Hyper-coal, desulfurization behavior was investigated by oxidation using hydrogen peroxide and acetic anhydride at room temperature and by pyrolyzing the treated sample under nitrogen stream. XANES analysis showed that the Hyper-coal contained only thiophenic sulfur and that the thiophenic sulfur changed to sulfone during the oxidation treatment. High removal extent of sulfur with high char yield was achieved by pyrolyzing the oxidized sample prepared at room temperature for 24 hour.</p>
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No.1-12 Distribution of Sulfur during Solvent Extraction of Coals
TAMURA Mami, KATO Takahiro, OKAWA Hirokazu, SUGAWARA Katsuyasu
Proceedings of Conference on Coal Science 2017 - 2017 The Japan Institute of Energy
<p>In a series of studies on the development of coal utilization process with pre-desulfurization, three types of coal were extracted by 1-methylnapthalene and sulfur distribution from raw coals to products (Soluble, Residue and Deposit) was clarified. XANES analysis indicated that most of pyritic sulfur was distributed to Residue. Soluble contained no inorganic sulfur. Every Soluble obtained from three types of coal contained organic sulfur, especially thiophenic sulfur only. Thiophenic sulfur content in Soluble decreased linearly with the increase of the steps of extraction using an ionic liquid of imidazolium type.</p>
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Desulfurization of coal soluble by multistep extraction using ionic liquids
Katsuyasu Sugawara, Mami Tamura, Takahiro Kato, Hirokazu Okawa
6th International Conference on Sustainable Energy & Environment (SEE2016) (Bangkok) 2016.11 - 2016.11
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Effect of ultrasound irradiation on size and morphology of scorodite particles synthesized under different acidic conditions
Yuya Kitamura, Hirokazu Okawa, Takahiro Kato, Katsuyasu Sugawara
Symposium on UltraSonic Electronics (USE2016) (Busan, Korea) 2016.11 - 2016.11
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Utilization of ultrasonic atomization for dust control in underground mining
Hirokazu Okawa, Kentaro Nishi, Youhei Kawamura, Takahiro Kato, Katsuyasu Sugawara
Symposium on UltraSonic Electronics (USE2016) (Busan, Korea) 2016.11 - 2016.11
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The desulphurization process of bitumen using ultrasound
Wan Mohamad Ikhwan bin Wan Kamal, Hirokazu Okawa, Takahiro Kato, Katsuyasu Sugawara
Symposium on UltraSonic Electronics (USE2016) (Busan, Korea) 2016.11 - 2016.11
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Sulfur removal from Thai lignite by liquid-phase oxidation
Takahiro Kato, Yuuki Nagai, Hirokazu Okawa, Katsuyasu Sugawara
6th International Conference on Sustainable Energy & Environment (SEE2016) (Bangkok) 2016.11 - 2016.11
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Multi-step Desulfurization of Coal Soluble Using Ionic Liquid
Takahiro Kato, Mami Tamura, Hirokazu Okawa, Katsuyasu Sugawara
2016.10 - 2016.10
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Recovery of Precious Metals from Secondary Resource by Using Coa
Kosuke Sakusabe, Takahiro Kato, Hirokazu Okawa, Katsuyasu Sugawara
2016.10 - 2016.10
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Recovery of Valuable Elements from E-waste by Chlorination
Takahiro Kato, Katsuyasu Sugawara
Asian Pacific Confederation of Chemical Engineering 2015(APCChE 2015) (Melbourne, Australia) 2015.09 - 2015.10
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Desulphurization of Coal Soluble Using Ionic Liquids
Mami Tamura, Takahiro Kato, Hirokazu Okawa and Katsuyasu Sugawara
International Conference on Coal Science & Technology 2015 (ICCS&T 2015) (Melbourne, Australia) 2015.09 - 2015.10
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Sonochemical Synthesis of Matel Nanoparticles onto Cathode Materials for Lithium Ion Battery
Hirokazu Okawa, Yuki Ono, Misaki Takai, Takahiro Kato, Mineo Sato, Katsuyasu Sugawara
Sonochemical Synthesis of Matel Nanoparticles onto Cathode Materials for Lithium Ion Battery (AOSS-2) (Kuala Lumpur, Malaysia) 2015.07 - 2015.07
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New recovery process of gold from incinerated ash by chlorination
Takahiro Kato, Hirokazu Okawa, Katsuyasu Sugawara
5th International Conference on Characterization and Control of Interfaces for High Quality Advanced Materials (ICCCI 2015) (Kurashiki, Japan) 2015.07 - 2015.07
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Removal of Organic Sulfur from Model Fuel and Coal Extract
Katsuyasu Sugawara, Mami Tamura, Takahiro Kato, Hirokazu Okawa
12th Eco-Energy and Materials Science and Engineering Symposium (12th EMSES) (Krabi, Thailand) 2015.06 - 2015.06
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Selective Removal of Organic Sulfur in Fuels
•Mami Tamura, Asuka Sasaki, Takahiro Kato, Katsuyasu Sugawara
5th International Conference on Sustainable Energy and Environment (SEE2014) (Bangkok) 2014.11 - 2014.11