105 research outputs found
Selective production of valuable chemicals from biomass by two-step conversion combining pre-oxidation and hydrothermal degradation
Biomass is getting notable as a new energy resource to replace fossil resources and to restrain CO₂ emission recently. However, it is obvious that the energy use of biomass is unsuitable for its limit of available amounts. Consequently, we investigated the possibility of new refinery scheme of biomass to utilize biomass as an alternative raw material to fossil resources with suggested two-step treatment method. We oxidized cellulose and biomass with H₂O₂ first and put the residue into hydrothermal condition to obtain some specific chemicals. Through the first oxidation of cellulose, 0.26 g/g-cellulose of organic acid was obtained, and 0.35 g/g-cellulose of oxalic acid was obtained under the catalytic condition. Both cedar and cellulose decreased their crystallinity through the first oxidation and increased their reactivity, we could obtain hydroxymethylfurfural(HMF) from cellulose and biomass through the hydrothermal degradation, 0.11 g/g-cellulose and 0.12 g/g-cedar respectively
Saccharification of lignocellulosic biomass under mild condition using ionic liquid
Biomass is expected to be an alternative resource to fossil resources. In this study, the development of a biomass conversion method into the valuable chemical, reducing sugar, was examined. For the conversion, thermochemical technology was focused on for its advantage of short reaction time, and ionic liquid was focused on as a reagent to overcome the unpreferable disadvantage of thermochemical technology, which is the low selectivity. Cedar and crystalline cellulose were pretreated with ionic liquid for reforming into desirable precursors of reducing sugar. Especially when they were pretreated by 1-ethyl-3-methylimidazolium methylphosphonate at 150°C for 1 h, the pretreatment worked effectively by decreasing the crystallinity of samples. Pretreated cedar and crystalline cellulose were converted into reducing sugar under hydrothermal conditions, respectively, by 39 C-% and 90 C-%. Recovery of ionic liquid was also examined. When cedar was used as a material, lignin was dissolved into ionic liquid through pretreatment, which was undesirable because of difficult separation thereof. When crystalline cellulose was used as a material, 98.3% of the ionic liquid was recovered after the conversion with the highest yield of reducing sugar (90 C-%)
Design Strategy for Performance Enhancement of Vertical Plate Microdistillators
Microdevices have been actively implemented in chemical processes, such as in mixing and reactions. However, microseparation devices, excluding extraction devices, are still under development. In distillation, the use of microdevices has been expected to improve separation performance, as their large specific surface area enables a rapid vapor–liquid equilibrium and for large temperature gradients to be easily realized. In this study, improvements in throughput and product purities in microdistillation devices were achieved for ethyl acetate–toluene distillation. At low feedstock flow rates, ethyl acetate was successfully purified to 99.5 wt%. Although the performance decreased with increasing feedstock flow rate, by increasing the channel length, this performance decrease was suppressed even at high flow rates. The thickness of the channel was also important, and the highest performance was observed at the lowest thickness of 0.5 mm. A performance evaluation using the HETP showed that the efficiency was seven times higher than that of conventional packed column distillators
Continuous 5-hydroxymethylfurfural production from monosaccharides in a microreactor
5-Hydroxymethylfurfural (HMF) was effectively produced from monosaccharides in a microreactor. A biphasic reaction system was employed to achieve the immediate extraction of produced HMF and suppress the overreaction. A microreactor was utilized to ensure that the reaction occurred under segmented flow to enhance the extraction efficiency. Through many attempts using phosphate buffer saline (PBS) as the reaction phase and 2-sec-butyl phenol (2BP) as the extraction phase, the favorable conditions were determined. By using PBS with pH of 2.0 and 2BP at a volume ratio of 3 to PBS, 80.9 mol % of fructose and 75.7 mol % of glucose were converted into HMF, respectively, at 180 °C. By comparing the results obtained through monophasic reactions, it was confirmed that the biphasic system successfully suppressed both the overreaction and the byproducts. The system employed only a simple experimental apparatus and the acid solution and organic solvent reagents without any complex expensive catalyst
Contactless mass transfer for intra-droplet extraction
This study demonstrates the possibility of “contactless” mass transfer between two aqueous slugs (droplets) separated by an oil slug in Taylor flow inside milli-channels. Separation of the alternating aqueous slugs at the outlet was performed by switching a couple of solenoid valves at branched outlets according to signals obtained by an optical sensor at the branch. Transfer of bromothymol blue (BTB) from acidic to basic aqueous slugs was performed for demonstration. In some cases, aqueous slugs separated by oil, merged catching on each other due to the velocity difference. Interfacial tension which was affected by the solute concentration was responsible for the velocity difference. Position-specific mass transfer activity at the rear end of the aqueous slugs was found on the course of the experiment. A meandering channel decreased the velocity difference and enhanced mass transfer. Almost complete (93%) transfer of BTB was achieved within a short residence time of several minutes under optimized conditions. The presented system opens a way for advanced separation using minimum amounts of the oil phase and allows concentrating the solute by altering relative lengths of the sender and receiver slugs
Experimental Investigation of the Cs Behavior in the Cesiated H- Ion Source During High Power Long Beam Operation
The behavior of the Cesium (Cs) in the Cs-seeded negative ion sources has been investigated experimentally under the beam accelerations of up to 0.5 MeV. The pulse length was extended to 100 s to catch the precise variations of the Cs D2 emission, discharge power, negative ion current and temperatures in the ion source. The variations of the negative ions were estimated by the beam current and the heat loads in the accelerator. This experiment shows that the buildup of temperature in the chamber walls lead to the evaporation of deposited Cs to enter the plasma region and influence the H- ion production. The H- ion beams were sustained stably by reducing the temperature rise of the chamber wall below 50 ℃. A stable long pulse beam could be achieved through the temperature control of the surfaces inside the source chamber walls
2017~2019年度 関西大学研究拠点形成支援経費研究成果報告書
目次・研究成果の概要・2-1 工藤 宏人・宮前 翼・上田 正人・村山 憲弘・林 順一 "ノーリア骨格をテンプレートとした空孔内に水酸基を有する架橋化合物の合成とそれらの金属イオン包接性能" ネットワークポリマー論文集 vol.41, No.2, 65 - 71 (2020).・2-2 Mitsuaki Matsuoka, Kaho Yokoyama, Kohei Okura, Norihiro Murayama, Masato Ueda, Makio Naito " Synthesis of Geopolymers from Mechanically Activated Coal Fly Ash and Improvement of Their Mechanical Properties" Minerals 9, 791- 801 (2019).・2-3 Daisuke Shimoyama, Ryo Sekiya, Hiroto Kudo, Takeharu Haino, "Feet-to-Feet Connected Trisresorcinarenes" Organic Letters 22, 352 - 356 (2019).・2-4 Masato Ueda, Masahiko Ikeda, Shigeo Mori, Kenji Doi, Hisashi Kitagaki, Shuntaro Terauchi "Mechanical Properties of Additively Manufactured Porous Titanium with Sub-Millimetre Structural Units" Materials Transactions Vol.60, No.9, 1792 - 1798 (2019).・2-5 五十井 浩平・白杉 文香・松岡 光昭・林 順一・村山 憲弘 "種々のMg-Fe系複合酸化物を用いた希薄水溶液中のホウ素およびヒ素の除去" 環境資源工学 66, 29 - 35 (2019).・2-6 Toru Maruyama, Mitsuyoshi Tamaki, Keisuke Nakamura, Gou Nakamura "EFFECT OF MOLTEN METAL TEMPERATURE ON MOLD FILLING IN EVAPORATIVE PATTERN CASTING" International Journal of Metalcasting 13, 611–617 (2019).・2-7 Ryuta Saito, Toru Maruyama, Toshiki Nakamura, Hitoshi Yanagitani, Takahiro Sakai, Kouji Nakamoto "Influence of Tellurium Addition to Spheroidal Graphite Cast Iron on the Number of Graphite Particles" International Journal of Metalcasting Vol.13, 3, 571-577 (2018).・2-8 Masato Ueda, Rika Yamaguchi, Chika Fujita, Masahiko Ikeda "Control of Cell Adhesion on Titanium Dioxide by Light Irradiation" Materials Science Forum Vol.941, 2507 - 2512 (2018).・2-9 Hiroto Kudo, Mari Fukunaga, Kohei Shiotsuki, Hiroya Takeda, Hiroki Yamamoto, Takahiro Kozawa, Takeo Watanabe "Synthesis of hyperbranched polyacetals containing C-(4-t-butylbenz)calix[4]resorcinarene: Resist properties for extreme ultraviolet (EUV) lithography" Reactive and Functional Polymers 131, 361 - 367 (2018).・2-10 大隈 修・前 一廣・林 順一 "直接液化による豪州ビクトリア褐炭の高度利用 : 改新BCLプロセスによる化学原料の生産" Journal of the Japan Institute of Energy 98, 17 - 26 (2019).・2-11 Issei Suzuki, Ayako Kakinuma, Masato Ueda, Takahisa Omata "Flux growth of β-NaGaO₂ single crystals" Journal of Crystal Growth 504, 26 -30 (2018).・2-12 上田 正人、坂本 貴則、池田 勝彦 "電気抵抗率の精密測定による純チタンの組織評価" 環境資源工学 65, 74 -76 (2018).・2-13 Satoshi Imasaka, Hiroyasu Ishii, Jun\u27ichi Hayashi, Sadao Araki, Hideki Yamamoto "Synthesis of CHA-type titanosilicate zeolites using titanium oxide as Ti source and evaluation of their physicochemical properties" Microporous and Mesoporous Materials 273, 243-248 (2019).・2-14 Hiroto Kudo, Shizuya Ohori, Hiroya Takeda, Hiroki Ogawa, Takeo Watanbe, Hiroki Yamamoto, Takahiro Kozawa "Synthesis and Property of Tannic Acid Derivatives and Their Application for Extreme Ultraviolet Laser Lithography System" Journal of Photopolymer Science and Technology Vol.31, 221 - 225 (2018).・2-15 Hiroto Kudo, Tsubasa Miyamae, Kouta Kitagawa, Kohei Isoi, Norihiro Murayama, Jun\u27ichi Hayashi " Synthesis and Metal-Complexation Ability of Cross-Linking Materials Containing Noria-Templated Cavities with Pendant Carboxylic Acid Groups" Chemistry Select 3, 2223 - 2228 (2018).・2-16 上田 正人、池田 勝彦、土井 研児、 森 重雄、北垣 壽、寺内 俊太郎、関 あずさ "骨部分置換用ポーラスチタン : ポリグリコール酸 : 炭酸カルシウム複合体の開発" 高分子論文集 Vol.75, No.1, 69 - 74 (2018).・2-17 Alexandru C Sonoc, Jacob Jeswiet, Norihiro Murayama, Junji Shibata "A study of the application of Donnan dialysis to the recycling of lithium ion batteries" Hydrometallurgy 175, 133 - 143 (2018).2-3は、著作権の関係により非公開としております。2-8は、著作権の関係により非公開としております。2-9は、著作権の関係により非公開としております。2-10は、著作権の関係により非公開としております。2-11は、著作権の関係により非公開としております。2-16は、著作権の関係により非公開としております
Design and operation of gas–liquid slug flow in miniaturized channels for rapid mass transfer
The influences of operating parameters such as channel size, flow rate, and void fraction on the mass transfer rate in the gas–liquid slug flow are investigated to establish a design method to determine the parameters for rapid mass transfer. From the experimental results, the turnover index, including the slug linear velocity, its length, and the channel size that represents the turnover frequency of the internal circulation flow, is proposed. For PTFE tube in which no liquid film exists in slug flow, a master curve is derived from the relationship between the mass transfer coefficient and the turnover index. For each channel material, the Sherwood number is also roughly correlated with the Peclet number. These correlations make it possible to arbitrarily determine a set of operating parameters to achieve the desired mass transfer rate. However, the turnover index and the Peclet number include the slug length, which cannot be controlled directly. The relationship between the slug length and the operating parameters is also investigated. The slug volume mainly depends on the inner diameter (i.d.) of a union tee. At a fixed union tee i.d., the slug length is controlled through the exit i.d. of the channel connected to the union tee and the void fraction. Thus, the final slug length depends on the union tee and exit channel inner diameters. At low flow rates, the gas and liquid collision angle is significant in determining the slug length
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