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記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.2355/isijinternational.isijint-2022-537

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.cej.2023.143891

記述言語：英語   掲載種別：研究論文（学術雑誌）  

<jats:p>We have studied the unique reaction acceleration phenomenon in the mixture and discussed the limitations of the Langmuir–Hinshelwood model for a solid-catalysed reaction.</jats:p>

DOI： 10.1039/d3re00032j

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Fast mixing is an essential feature of a microreactor. This study reveals the critical role of microscopic fluid incorporation on fast chemical reactions in a microreactor. The vortices in a microreactor produce tiny fluid segments, and the incorporation of these segments into the surrounding fluid triggers chemical reactions. The selectivity of chemical reactions highly depends on the type of the fluid segment incorporated into the fluid. Microreactor operations that consider incorporative mixing can achieve better reaction results, even with slow mixing. For example, a tee mixer showed better reaction performance with the vertical confluence configuration than with the symmetric configuration, although the symmetric 180-degree confluence provides more intense mixing. Computational fluid dynamics (CFD) simulations showed that vertical confluence enabled the division and incorporation of a stream from the horizontal inlet into another stream. The appropriate inlet designation is vital when two inlets of a microreactor differ in dimensions, directions, or positions because the different inlets provide different mixing profiles. The two inlets of the microreactor were distinguishable even though the fabrication error was insignificant. For instance, feed orientations changed the side-product yield seven times in a 3D-printed microreactor. Moreover, the impact of incorporative mixing on particle synthesis was confirmed. Switching the two inlets significantly influenced the morphology and size of the synthesized particles by changing the initial nucleation environment. In conclusion, considering incorporative mixing and optimal inlet orientation will enhance the performance and flexibility of microreaction technology.

DOI： 10.1016/j.cej.2022.138942

記述言語：英語   掲載種別：研究論文（学術雑誌）  

<jats:p>An enzyme membrane reactor is an attractive tool for producing oligosaccharides from biomass-based polysaccharides. However, kinetic modeling and reactor design based on the rate equations have rarely been reported for enzyme membrane reactors because of the difficulty in tracing the depolymerization process. In this study, a simplified reaction model based on Michaelis–Menten-type kinetics has been built to simulate the enzyme membrane reactor. Ramping various species into reactant, target, and byproduct worked well for discussing reactor performance. The use of a membrane with a molecular weight cut-off (MWCO) of 10 kDa with continuous feeding of the reactant was suggested for the efficient production of chitosan hexamer and pentamer by enzymatic hydrolysis of chitosan.</jats:p>

DOI： 10.3390/fermentation8120701

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.2355/isijinternational.isijint-2020-726

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jaap.2022.105658

記述言語：その他  

DOI： 10.1002/9783527830190.ch5

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Glucose is a key compound for future biomass-based energy and chemical industry. An availability of glucose from abundant lignocellulosic biomass is limited because of a slow reaction rate and costly feed materials in a conventional enzymatic hydrolysis of cellulose. The present work investigated the production of glucose with hydrolysis of anhydrosugars produced by cellulose pyrolysis that is a fast reaction with no requirement for other chemicals to feed. A commercially available solid acid was employed as the hydrolysis catalyst for enabling a direct use of glucose aqueous solution without posttreatment such as separation. The experiments using a model anhydrosugar, levoglucosan (LGA), as feedstock revealed a selective activity of the catalyst to produce glucose even at the high concentration of 2.7 M and the catalytic stability in 15 h run of the reaction using a continuous flow reactor. The catalyst worked for the reaction with a cellulose-derived bio-oil as the feedstock to selectively produce glucose mainly from LGA. However, the activity gradually decreased due to deposition of carbonaceous materials from compounds other than LGA over the catalyst, indicating the necessity for eliminating those compounds before the hydrolysis.

DOI： 10.4028/p-3800i8

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.energyfuels.2c01722

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.2355/isijinternational.isijint-2022-159

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.2355/isijinternational.ISIJINT-2022-013

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsomega.2c03286

記述言語：その他   掲載種別：研究論文（学術雑誌）  

21 types of modifiers are screened for palladium catalysed semi-hydrogenation of alkynes with varying catalyst type, reaction time, and target substrate using an automated flow reactor system.

DOI： 10.1039/d2re00147k

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.energyfuels.2c01352

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.biortech.2021.126323

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acssuschemeng.1c07877

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.energyfuels.1c01889

記述言語：その他   掲載種別：研究論文（学術雑誌）  

An automated microflow measurement system for the kinetic study of racemization of dynamic chiral molecules was developed. This system facilitated the analysis of fast racemization within several seconds at elevated temperatures owing to its rapid heating ability, high performance for controlling short residence times, and ease of connection to HPLC systems for direct measurement of the enantiomeric purity. A more precise analysis was realized by combination of microflow and common batch measurements over a broad range of temperatures.

DOI： 10.1021/acs.joc.1c00914

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.energyfuels.1c01062

記述言語：その他   掲載種別：研究論文（学術雑誌）  

The pyrolysis of cellulose produces anhydrosugars, levoglucosan (LGA) in particular, as a primary product. In this work, the liquid phase conversion of anhydrosugars over solid acid catalysts was investigated, mainly using LGA, as a method for producing levoglucosenone (LGO), which is a bio-renewable platform for fine and commodity chemicals. The screening of typical organic solvents revealed they had a significant influence on the type of reaction selectivity and identified dimethyl sulfoxide (DMSO) as a suitable solvent. Among the solid acid catalysts examined, Amberlyst 70 in combination with DMSO was found to work the best, producing LGO with a yield of up to 32.3&#37;-C. The yield of LGO was further improved to 40.4&#37;-C by in-situ removal of water, which promoted undesired reactions, such as hydrolysis of LGA and isomerization of LGO to hydroxymethylfurfural. Moreover, an experiment using bio-oil, derived from cellulose pyrolysis, as the feedstock showed that a portion of heavier saccharides contributed as a source of LGO without inhibiting the conversion of LGA.

DOI： 10.1016/j.fuproc.2020.106625

記述言語：その他   掲載種別：研究論文（学術雑誌）  

The present study investigated oxidation of pulverized Japanese cedar with O2 in hot-compressed alkaline water, employing a newly developed flow-through fixed-bed reactor (percolator). It allowed us to determine the rate of the primary extraction that was free from the secondary reactions of extract in the aqueous phase and those over the residual solid, solubility of extractable matter, and mass transport processes. Quantitative kinetic analysis revealed that the cedar consisted of three kinetic components (C1-C3) that underwent extraction in parallel following first-order kinetics with different rate constants. Further analysis revealed the chemical compositions of the kinetic components, which were mixtures of carbohydrates and lignin. C1 was converted most rapidly by nonoxidative reactions such as alkali-catalyzed hydrolysis, while C2 was converted by oxidative degradation. The product distributions from C1 and C2 (CO2, lower organic acids, oligosaccharides, acid-soluble, and acid-insoluble lignins) were steady throughout their conversion. Both C1 and C2 thus behaved as single reactants; nevertheless, those were lignin/carbohydrates mixtures. It was also demonstrated that the extraction rate of C2 was proportional to the concentration of dissolved O2. C3 was the most refractory component, consisting mainly of glucan and very minimally of the lignin, xylan, mannan, galactan, and arabinan.

DOI： 10.1021/acsomega.0c05154

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1038/s41598-020-64520-4

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Delignification is essential in effective utilization of carbohydrates of lignocellulosic biomass. Characteristics of the delignification are important for the yield and property of the resulting carbohydrates. Oxidation with O2 of biomass in alkaline water can potentially produce high-purity cellulose at high yield. The present authors chose a Japanese cedar and investigated its oxidative delignification at 90 °C. The delignification selectivity was determined mainly by the chemical structures of lignin and cellulose. Treatment conditions, except for temperature, hardly changed the relationship between delignification rate and cellulose retention. During the treatment, dissolved lignin underwent chemical condensation in the aqueous phase. This "unfavorable"condensation consumed O2-derived active species, slowing down further delignification. Repeated short-time oxidation with renewal of alkaline water suppressed the condensation, enhancing the delignification. Repetition of 2-h treatments four times achieved 96&#37; delignification, which was 8&#37; higher than a single 8-h treatment at 130 °C.

DOI： 10.1021/acsomega.0c03953

記述言語：その他   掲載種別：研究論文（学術雑誌）  

We have demonstrated a sequence of degradation, dissolution and catalytic hydrothermal gasification (CHTG) of lignite in alkaline water. A Victorian lignite was subjected to hydrothermal treatment (HT) in an aqueous solution of NaOH at 250 °C, and then oxidation with pressurized O at 100 °C. The sequential HT and oxidation solubilized a 95&#37; portion of the lignite on mass/carbon bases. The resulting solution was further converted by CHTG in a flow reactor at 350 °C for 10 h, employing a ruthenium/activated-charcoal catalyst (ruthenium loading; 16 wt&#37;). The initial carbon conversion to gas was as high as 98&#37; while CH , CO and H were produced. The conversion gradually decreased due to coke deposition over the catalyst but was near steady around 83&#37; at 8–10 h. The solubilized lignite consisted of compounds with molecular mass up to 5,000. The heavier portion (molecular mass > 1,000) was responsible for the coke formation and accumulation that caused the catalyst deactivation. 2 4 2 2

DOI： 10.1016/j.fuel.2020.118329

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Global iron and steel production continues to expand. The iron-making industry is, however, one of the main contributors to global warming due to its reliance on fossil fuel-based high temperature processes. Therefore, alternative green approaches to iron-making are highly desired. Herein, we propose a new concept of iron-making, which consists of a sequence of known reactions: the dissolution of iron from iron ore using oxalic acid to obtain a Fe(III) oxalate aqueous solution, followed by the photochemical reduction of Fe(III) oxalate to Fe(II) oxalate as a solid precipitate, and the pyrolytic reduction of Fe(II) oxalate to metallic iron. By harnessing the chemical characteristics of oxalic acid and iron oxalates, the method is expected to produce high-quality iron at low temperatures. Moreover, the recovery of carbon oxides, generated during iron-making, for the synthesis of oxalic acid enables the iron-making without having carbon in the stoichiometry. The present study explains the key chemical concepts of the process, experimentally demonstrates the iron-making, and discusses the challenges and barriers to industrial application. In the experiment, according to the proposed scheme, three different iron sources were successfully converted into metallic iron. The yield and quality (purity) of the iron product depended on the metallic composition of the feedstock. In the absence of impurity metals, near-complete recovery of pure iron was possible. Alkaline earth and transition metals were identified as impurities that affected process performance and product quality. The iron dissolution needed a relatively long reaction time to achieve sufficient conversion under the conditions employed in this study, rendering it a rate-determining step that influenced overall iron productivity.

DOI： 10.1021/acssuschemeng.0c03593

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Pyrolysis is the simplest way to convert lignin into phenolic compounds as monomers but inevitably producing oligomers as heavy oil (HO). We propose a particular type of pyrolysis, which recycles such oligomers entirely to pyrolysis, employing the parent lignin for their capture/recycling without any chemicals and catalysts. Continuous pyrolysis of a Japanese cedar lignin was simulated by repeating fixed-bed pyrolysis of HO-loaded lignin and demonstrated steady state of yields of gas, water, char, and light oil (LO) that consisted solely of monomers and furans and lower acids, with neither discharge of HO from the system nor accumulation therein. HO was converted to char, water, and LO with once-through conversion of around 47&#37;, which was contributed by not only self-pyrolysis of HO but also its copyrolysis/carbonization with the parent lignin. The HO recycling increases the LO yield by a factor of 1.4. Catechols (catechol and methylcatechols) and guaiacols (guaiacol, 4-ethylguaiacol, creosol, vanillin, and apocynin) constitute 42 and 22 wt &#37; of LO, respectively. The char shows an increased production in the sequential runs with a near-unchanged elemental composition, volatile matter content, and calorific value.

DOI： 10.1021/acs.energyfuels.0c01164

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsomega.0c00399

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This study aimed to investigate the effect of carbon derived from glucose (C) on the physicochemical characteristics and catalytic activity of Ni, supported over SiO , ZSM-5, and TiO in methane dry reforming. Among the Ni catalysts without C, Ni/SiO exhibited the highest CH -CO conversion and stability at all experimented temperatures. On the other hand, the C-incorporated catalysts prepared by glucose impregnation, followed by pyrolysis, showed dissimilar performances. C improved the stability of Ni/SiO in the reforming at 650 C and 750 C and increased the CH and CO conversion to the level close to the thermodynamic equilibrium at 850 C. However, this element did not substantially affect the activity of Ni/ZSM-5 and exerted a retarding effect on Ni/TiO . Characterizations with H -TPD, XRD, EXAFS, and STEM-EDS revealed that the different influences of C by the supports were attributed to the extent of metal dispersion and metal-support interaction. 2 2 2 4 2 2 4 2 2 2 ◦ ◦ ◦

DOI： 10.3390/catal10010021

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Potassium (K)-catalyzed CO gasification of lignite char was studied with a particular focus on the change in catalyst activity with the char conversion (X) at 800-900 °C. Char samples were prepared from an Indonesian lignite by a sequence of complete removal of inherent metallic species and mineral matter, K-loading by ion-exchange, and pyrolysis. The catalytic activity of K (kcat′) was defined as the rate of catalytic gasification (after elimination of the rate of non-catalytic gasification and that of K volatilization from total mass release rate from char) per amount of K retained by the gasifying char. kcat′ increased by a factor of 5-20 with X over its range up to 0.98-0.99, depending on the initial K concentration in the char (m ), ranging 0.16-1.4 wt %-daf. Such significant increase in kcat′ was due to the change in not the intrinsic reactivity of char but its porous nature, that is, the size and volume of pores that retained the K catalyst. At X < 0.4, the entire portion of the K catalyst was confined in micropores (width <2.0 nm) having relatively small kcat′, although it increased gradually. At X > 0.4, the gasification created greater mesopores (width >2.0 nm), providing spaces for growth in the size of the K catalyst and allowing promotion of its activity. However, for low m , its major portion continued to stay in micropores with a limited increase in kcat′. 2 cat,0 cat,0

DOI： 10.1021/acs.energyfuels.9b03630

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.energyfuels.9b02939

記述言語：その他   掲載種別：研究論文（学術雑誌）  

This study has experimentally proven an approach to integrate electric energy and chemical energy of biomass into chemical energy of hydrogen by biochar-assisted water electrolysis (BAWE). This type of electrolysis, in other words, electrochemical gasification, consists of hydrogen formation at the cathode and biochar oxidation at the anode, instead of O formation. Different from traditional gasification of biochar, BAWE is operated at a temperature below 100 °C and normal pressure. Linear sweep voltammetry showed that the electrolysis of acidified water, when suspended with biochar, occurred at an interelectrode potential as low as 0.5 V, which was much smaller than 1.23 V, the standard potential to split water into hydrogen and oxygen at 25 °C. The performance of biochar depended significantly upon the carbonization temperature for its preparation. It was found that 850 °C was the best carbonization temperature that provided an optimum combination of specific surface area and carbon-type distribution. It was revealed by continuous BAWE that the formation of O-containing functional groups on the biochar surface was predominant over CO formation at the anode, while H was formed obeying stoichiometry at the cathode. Accumulation of the O-containing groups on the biochar surface decreased its electrochemical reactivity, slowing the electrolysis. Thermal treatment at 850 °C removed the major portion of O-containing groups from the spent biochar, fully recuperating its electrochemical reactivity. CO gasification enhanced the biochar activity, and its effect went far beyond the heat treatment. On the basis of the above-mentioned characteristics of BAWE, its combination with CO gasification as the biochar recuperator as well as syngas producer is proposed. 2 2 2 2 2

DOI： 10.1021/acs.energyfuels.9b02925

記述言語：その他   掲載種別：研究論文（学術雑誌）  

An inkjet mixing system was investigated to synthesize lipid nanoparticles (LNP) by mixing lipid ethanol and aqueous saline solutions. The system was employed to help minimize drug loss. The quick mixing of the droplets enabled the synthesis of small LNP while reducing the excess amount of saline solution that would contain drugs. The system also features minimal usage of reagents. A high relative velocity of the droplets and moderate values of the impact parameter were necessary for successful mixing. Faster droplets should collide with the upper or horizontal level of slower droplets to promote mixing. A horizontal spin of the coalesced droplets was favored rather than a vertical spin.

DOI： 10.1002/ceat.201900041

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.energyfuels.9b02946

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Microreactors have been utilized for controlling fast chemical reactions. However, the scale-up strategy for fast reactions is not established enough due to the difficulty in quantifying the effect of the reactor size on the mixing performance, heat removal, and observable reaction rate. We present a chart for analyzing the effect of the mixing rate on the observable kinetic constant and a chart for estimating the temperature increase in the reactor. By using these charts, the validity of the rate analysis and the maximum reactor diameter, which control the reaction temperature, were determined. Commercial computational fluid dynamics (CFD) software was employed to solve the partial differential equations and to build the charts, and experiments were conducted to validate the results. We demonstrated the concept by using the ultrafast organolithium reaction in milliseconds. The product throughput was increased eight times with a reactor diameter that was twice as wide as the original reactor.

DOI： 10.1021/acs.oprd.8b00356

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.langmuir.8b03516

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We extensively examined and discussed the performance of microjet mixers that consisted of two concentrically arranged tubes. The orientation of the feed streams with respect to the inner and outer inlets was the crucial factor for promoting the desired reaction. The Reynolds number after jetting and the velocity ratio of the inner and outer fluids were the key variables for promoting vigorous jetting and efficient mixing. By choosing the appropriate operating conditions, the microjet mixers exhibited excellent performance. The design protocol for microjet mixers was established based on mixing time measurements. We successfully maximized the throughput in one channel and numbered-up the microjet mixers. The microjet mixers also proved to be useful for treating viscous fluids with the appropriate choice of the feed orientation. The complete mixing of water with a 200 times more viscous fluid was achieved in 20 ms.

DOI： 10.1039/c7re00051k

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.cep.2017.05.016

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The relationship between mixing history and reaction performance in microreactors using computational fluid dynamics (CFD) simulations is identified. In the idealized, simplified mixing model, mixing proceeds linearly and only the mixing time determined the reaction performance. However, in the case of realistic models where mixing proceeds unequally, the partial rapid progression of mixing, more than the mixing time, significantly impacts the reaction. The use of the fluid segment size distribution to capture this effect is proposed. The effective Damköhler number derived from the fluid segment size distribution predicted the reaction yield well. To demonstrate the utility of the mixing profile design strategy, we fabricated a novel micromixer with multiple partial rapid mixing zones. This micromixer achieved excellent results both in a CFD simulation and an experiment.

DOI： 10.1002/aic.15082

開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2020年6月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Wuhan   国名：中華人民共和国  

開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：鹿児島   国名：日本国  

開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：鹿児島   国名：日本国  

開催年月日： 2020年6月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Hokkaido   国名：日本国  

開催年月日： 2020年6月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Fukuoka   国名：日本国  

開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：Fukuoka   国名：日本国  

開催年月日： 2020年6月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Hokkaido   国名：日本国  

開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2019年5月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Wuhan   国名：中華人民共和国  

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