|Oshima Kazumasa||Last modified date：2021.06.23|
Assistant Professor / Molecular System and Biosystem Engineering Laboratory / Department of Chemical Engineering / Faculty of Engineering
|Oshima Kazumasa||Last modified date：2021.06.23|
|1.||Shinya Matsuda, Kazumasa Oshima, Masaki Hosaka, Shigeo Satokawa, Effect of annealing on the separation of resin from CFRP cross-ply laminate via electrical treatment, Composite Structures, 10.1016/j.compstruct.2019.111665, 234, 15, 2020.02, © 2019 Elsevier Ltd Carbon fiber reinforced plastics (CFRP) are desirable owing to their high specific strength and rigidity. Traditional recycling methods for these products such as thermal decomposition cause considerable damage to the carbon fibers. In search for better recycling methods, we explored the use of electrical treatment for the separation of resin. Herein, we investigated the effects of annealing on the separation of resin from a CFRP cross-ply laminate molded from unidirectional prepreg (carbon fiber/epoxy) using electrical treatment. The annealing of the CFRP cross-ply laminate [0°/90°]2s was performed at temperatures ranging from 60 °C to 450 °C, followed by the electrical treatment. Experimental results demonstrated that the separation of resin, without the carbon fiber damage, could be achieved by annealing at temperatures close to the epoxy decomposition temperature. For the non-annealed CFRP specimens, the separation of resin was achieved with considerable damage to the carbon fibers..|
|2.||Rapid removal of resin from a unidirectional carbon fiber reinforced plastic laminate by a high-voltage electrical treatment
© 2019 Elsevier B.V. Removal of epoxy resin from a unidirectional carbon fiber reinforced plastic (CFRP) laminate was achieved with an electrical treatment. The treatment was carried out using a two-electrode cell with the CFRP laminate as the anode, and the effect of applying a high voltage was investigated to reduce the treatment time. The results showed that a high voltage in the electrical treatment leads to high weight loss of the unidirectional CFRP laminate. In the digital microscope images of the residue obtained from the electrolyte after the treatment, fragments assumed to be resin were observed. The removal mechanism involved an electrochemical reaction; however, no decomposition product related to the resin was detected in the electrolyte after the treatment. The results supposed that the removal mechanism of the electrical treatment involved peeling off the resin by gas generated by water electrolysis..
|3.||Shohei Tada, Kazumasa Oshima, Yoshihiro Noda, Ryuji Kikuchi, Minoru Sohmiya, Tetsuo Honma, Shigeo Satokawa, Effects of Cu Precursor Type on the Catalytic Activity of Cu/ZrO2 towards Methanol Synthesis via CO2 Hydrogenation, Ind. Eng. Chem. Res., 10.1021/acs.iecr.9b03627, 58, 42, 19434-19445, 2019.09.|
|4.||Tomohiro Yabe, Kenta Mitarai, Kazumasa Oshima, Shuhei Ogo, Yasushi Sekine, Low-temperature dry reforming of methane to produce syngas in an electric field over La-doped Ni/ZrO2 catalysts, FUEL PROCESSING TECHNOLOGY, 10.1016/j.fuproc.2016.11.013, 158, 96-103, 2017.04, Dry reforming of methane (DRM) was conducted over various transition metal supported ZrO2 catalysts in an electric field. Catalyst of lwt%Ni/10 mol%La-ZrO2 showed high DRM activity even at 423 K of external temperature, at which no DRM proceeds in the conventional catalytic systems. By virtue of the low reaction temperature, low amounts of carbon deposition were confirmed even in conditions of high CH4 conversion in the electric field. The imposed electric power was correlated to with the catalytic activities in the electric field. Syngas is producible at low temperature with high energy efficiency. (C) 2016 Elsevier B.V. All rights reserved..|
|5.||R. Manabe, S. Okada, R. Inagaki, K. Oshima, S. Ogo, Y. Sekine, Surface Protonics Promotes Catalysis, SCIENTIFIC REPORTS, 10.1038/srep38007, 6, 38007, 2016.12, Catalytic steam reforming of methane for hydrogen production proceeds even at 473 K over 1 wt% Pd/CeO2 catalyst in an electric field, thanks to the surface protonics. Kinetic analyses demonstrated the synergetic effect between catalytic reaction and electric field, revealing strengthened water pressure dependence of the reaction rate when applying an electric field, with one-third the apparent activation energy at the lower reaction temperature range. Operando-IR measurements revealed that proton conduction via adsorbed water on the catalyst surface occurred during electric field application. Methane was activated by proton collision at the Pd-CeO2 interface, based on the inverse kinetic isotope effect. Proton conduction on the catalyst surface plays an important role in methane activation at low temperature. This report is the first describing promotion of the catalytic reaction by surface protonics..|
|6.||Yasushi Sekine, Kodai Yamagishi, Yukako Nogami, Ryo Manabe, Kazumasa Oshima, Shuhei Ogo, Low Temperature Catalytic Water Gas Shift in an Electric Field, CATALYSIS LETTERS, 10.1007/s10562-016-1765-y, 146, 8, 1423-1428, 2016.08, Catalytic water gas shift for hydrogen production in the temperature range of 423-873 K, was examined imposing an electric field to the catalyst bed. Reaction trends were investigated based on thermodynamic equilibrium and chemical kinetic law. Pt/La-ZrO2 was chosen as an active catalyst through our screening tests, and the effect of the electric field on the catalytic activity was investigated by changing reaction temperatures and applied electric currents. Although the reaction was ruled by thermodynamic equilibrium at high temperatures, drastic promotion of the reaction by applying the electric field was observed at low temperatures in a kinetic region. Drastic decrease of apparent activation energy for WGS was observed by imposing the electric field to the catalyst bed. Various isotopic transient tests revealed that the reaction mechanism changed by the application of electric field, and redox mechanism using surface lattice oxygen played an important role in case of the catalytic WGS in the electric field.
|7.||Kazumasa Oshima, Tatsuya Shinagawa, Yukako Nogami, Ryo Manabe, Shuhei Ogo, Yasushi Sekine, Low temperature catalytic reverse water gas shift reaction assisted by an electric field, CATALYSIS TODAY, 10.1016/j.cattod.2013.11.035, 232, 27-32, 2014.09, Catalytic reverse water gas shift reaction was conducted in an electric field (denoted as E-RWGS) over various catalysts at low temperature as 423 K. A platinum catalyst supported on lanthanum doped zirconia (Pt/La-Zr02) showed the highest yield (ca. 40%) for the E-RWGS reaction even at such low temperature condition. In contrast to a bare oxide catalyst, metal loading catalysts showed higher activities and efficiencies for the reaction. Roles of the impregnated platinum and doped lanthanum on the catalytic activity were investigated, and we found that loaded platinum worked as an active site for the E-RWGS reaction, and La doping stabilized the structure of Zr02. The effect of the electric field was discussed based on thermodynamic evaluation and experimental results. C) 2013 Elsevier B.V. All rights reserved..|
|8.||Kazumasa Oshima, Keisuke Tanaka, Tomohiro Yabe, Eiichi Kikuchi, Yasushi Sekine, Oxidative coupling of methane using carbon dioxide in an electric field over La-ZrO2 catalyst at low external temperature, FUEL, 10.1016/j.fuel.2013.01.058, 107, 879-881, 2013.05, Oxidative coupling of methane using carbon dioxide (CO2-OCM) as an oxidant was conducted over several La- and Zr-based catalysts in an electric field at low external temperature of 423 K. Higher catalytic activity was obtained than in a conventional catalytic reaction over 10 mol% lanthanum-doped zirconia (La-ZrO2) in the electric field. Although the catalytic activity for the CO2-OCM was low over the La-ZrO2 at 1173 K without the application of the electric field, the electric field promoted catalytic activity even at 423 K external temperature. We optimized the amount of doping-La in the La-ZrO2 system, and characterized the effect of doping-La with XRD measurement. From these examinations, 5 mol% La-ZrO2 catalyst showed the highest activity. High catalytic activity was provided by the synergistic effect of the La- cation, tetragonal-ZrO2, and the electric field. (c) 2013 Elsevier Ltd. All rights reserved..|
|9.||Kazumasa Oshima, Tatsuya Shinagawa, Masayuki Haraguchi, Yasushi Sekine, Low temperature hydrogen production by catalytic steam reforming of methane in an electric field, INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, 10.1016/j.ijhydene.2012.12.069, 38, 7, 3003-3011, 2013.03, Catalytic steam reforming of methane in an electric field (electroreforming) at low temperatures such as 423 K was investigated. Pt catalysts supported on CeO2, CexZr1-xO2 solid solution and a physical mixture of CeO2 and other insulators (ZrO2, Al2O3 or SiO2) were used for electroreforming. Among these catalysts, Pt catalyst supported on CexZr1-xO2 solid solution showed the highest activity for electroreforming (CH4 conv. = 40.6% at 535.1 K). Results show that the interaction among the electrons, metal loading, and catalyst support was important for high catalytic activity on the electroreforming. Catalytic activity of the electroreforming increased in direct relation to the input current. Characterizations using X-ray diffraction (XRD), temperature programmed reduction with H-2 (H-2-TPR), and alternate current (AC) impedance measurement show that the catalyst structure is an important factor for activity of electroreforming. Copyright (c) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved..|
|10.||Kazumasa Oshima, Tatsuya Shinagawa, Yasushi Sekine, Methane Conversion Assisted by Plasma or Electric Field, JOURNAL OF THE JAPAN PETROLEUM INSTITUTE, 10.1627/jpi.56.11, 56, 1, 11-21, 2013.01, Direct conversion of methane to other valuable products such as ethylene, methanol, benzene, carbon, hydrogen, and syngas has been widely investigated. Such conversion requires high temperatures because of the strong C-H bond in CH4, and such high-temperature reactions present various problems: sequential reaction to decrease the selectivity to target products, need for multiple heat exchangers to use or recover high-temperature waste heat, materials that are stable at high temperatures, etc. To solve these problems, several trials have been undertaken to lower reaction temperatures using plasma, Non-Faradaic Electrochemical Modification of Catalytic Activity (NEMCA), and electric fields. This review describes recent trends in methane conversion, and describes our methods to lower the reaction temperature..|
|11.||Keisuke Tanaka, Yasushi Sekine, Kazumasa Oshima, Yoshitaka Tanaka, Masahiko Matsukata, Eiichi Kikuchi, Catalytic Oxidative Coupling of Methane Assisted by Electric Power over a Semiconductor Catalyst, CHEMISTRY LETTERS, 10.1246/cl.2012.351, 41, 4, 351-353, 2012.04, Oxidative coupling of methane (OCM) on La2O3 semiconductor catalysts at 423 K external temperature was investigated. DC power supplied from two electrodes in a catalyst bed enabled stable and selective production of C2H6 and C2H4 over Sr-La2O3 (Sr/La = 1/200 and 1/20), but plasma reactions proceeded over other catalysts. The electrical conductivity of the semiconductor catalyst was important for controlling this reaction. A high yield of C2 (49% selectivity, 51.3% O-2 conversion) was obtained using 2.7 W of electricity at a lower external temperature (423 K)..|