Editor-in-Chief
Manabu Shimada (Hiroshima University)

Associate Editor-in-Chiefs
Masahiro Shishido (Yamagata University)
Ken-Ichiro Sotowa (The University of Tokushima)

Editors
Choji Fukuhara (Shizuoka University)
Toshitaka Funazukuri (Chuo University)
Yoshihiro Hashimoto (Nagoya Institute of Technology)
Shunji Homma (Saitama University)
Jun-ichi Horiuchi (Kyoto Institute of Technology)
Yoshinori Itaya (Gifu University)
Masashi Iwata (Osaka Prefecture University)
Noriho Kamiya (Kyushu University)
In-Beum Lee (Pohang University of Science and Technology (POSTEC))
Kouji Maeda (University of Hyogo)
Hideyuki Matsumoto (National Institute of Advanced Industrial Science and Technology (AIST))
Michiaki Matsumoto (Doshisha University)
Nobuyoshi Nakagawa (Gunma University)
Tsuguhiko Nakagawa (Okayama Prefectural University)
Yasuya Nakayama (Kyushu University)
Masaru Noda (Fukuoka University)
Mikihiro Nomura (Shibaura Institute of Technology)
Eika W. Qian (Tokyo University of Agriculture and Technology)
Yuji Sakai (Kogakuin University)
Noriaki Sano (Kyoto University)
Naomi Shibasaki-Kitakawa (Tohoku University)
Hiroshi Suzuki (Kobe University)
Nobuhide Takahashi (Shinshu University)
Kazuhiro Takeda (Shizuoka University)
Shigeki Takishima (Hiroshima University)
Yoshifumi Tsuge (Kyushu University)
Tomoya Tsuji (Nihon University)
Shigeyuki Uemiya (Gifu University)
Da-Ming Wang (National Taiwan University)
Takayuki Watanabe (Kyushu University)
Takuji Yamamoto (University of Hyogo)
Tetsuya Yamamoto (Nagoya University)
Masahiro Yoshida (Kagoshima University)
Yasuo Yoshimi (Shibaura Institute of Technology)
Miki Yoshimune (National Institute of Advanced Industrial Science and Technology (AIST))

Editorial office:
The Society of Chemical Engineers, Japan
Kyoritsu Building, 4-6-19, Kohinata, Bunkyo-ku
Tokyo 112-0006, Japan
journal@scej.org

AIMS AND SCOPE:

Journal of Chemical Engineering of Japan, an official publication of the Society of Chemical Engineers, Japan, is dedicated to providing timely original research results in the broad field of chemical engineering ranging from fundamental principles to practical applications. Subject areas of this journal are listed below. Research works presented in the journal are considered to have significant and lasting value in chemical engineering.

Physical Properties and Physical Chemistry
Transport Phenomena and Fluid Engineering
Particle Engineering
Separation Engineering
Thermal Engineering
Chemical Reaction Engineering
Process Systems Engineering and Safety
Biochemical Food and Medical Engineering
Micro and Nano Systems
Materials Engineering and Interfacial Phenomena
Energy
Environment
Engineering Education

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To estimate the agglomeration weight for emulsion polymerization conducted in an agitated vessel, a simple method of combining a preliminary experiment and a CFD analysis is proposed. To get the relation between agglomeration weight and shear rate, the emulsion polymerization of interest (we adopted the styrene polymerization) was conducted in a vessel consisting of two-axial cylinders, which provides almost constant shear rate throughout vessel. To predict the shear rate experienced by a liquid or polymer, the trajectories of particles were obtained by CFD for the actual agitator adopted for emulsion polymerization. Employing these results, the agglomeration rate in emulsion polymerization in the real agitator equipped with a Maxblend could be estimated. The estimated result of agglomeration weight for emulsion polymerization shows good agreement with the experimental result conducted in the actual agitator.

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The drop breakup model in liquid–liquid agitation, which has been proposed by the authors, is extended theoretically and experimentally. The extended model provides a new correlation equation for the maximum stable drop size. The equation is shown to be useful in prediction of sizes of the maximum stable drops with various flow behavior.

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Sludge of coagulation-flocculation treatment is one of most costly and largest quantity products in the wastewater treatment process. In this work, titanium dioxide serves as a sludge reusing product in titanium tetrachloride flocculation process. The effect of TiCl₄ on humic acid (HA) coagulation removal in water was investigated. Reprocessing TiO₂ photocatalyst was analyzed by surface characterization and photoactivity. The coagulation results showed that the best removal of turbidity and DOC was from the addition 0.14 g/L TiCl₄ at pH 3. Titania powder prepared from coagulation sludge showed regular round particles with a dimension of around 15–30 nm. The crystal structure of TiO₂ was primary anatase. The primary element states of titania included Ti⁴⁺, O²⁻, and graphitic carbon. Photoactivity test results confirmed that reusing TiO₂ showed high dye AR27 photodegradation under acidic conditions with UV light irradiation. TiCl₄ coagulant and sludge reusing techniques provide a new concept which could be widely applied to treat waste sludge in the future.

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Amino acids were used to modify macroreticular ion exchange resin for the adsorptive capture of CO₂. Adsorption isotherms, adsorption rate curves, heats of adsorption, and gas separation performance were determined. It is found that the adsorption capacity of the resin increases significantly after the loading of amino acids. The adsorption progresses rapidly and reaches equilibrium within 3 min. The adsorption capacity decreases with the increasing temperature, and room temperature is a suitable condition that enables high adsorption of CO₂. The adsorbent can be promoted by water vapor in removing CO₂ effectively from gas mixtures. Ten continuous adsorption–desorption cycles was performed, showing that the adsorbent is of good regeneration performance and the adsorption capacity keeps at about 0.9 mmol/g after regeneration.

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Phosphate and fluoride ions were simultaneously removed from model industrial waste water, with the formation of fluorine-containing apatite. 70% of fluoride and 50% of phosphate ions were removed in the presence of calcium ion from calcium nitrate. Using scallop shell powder (calcite CaCO₃) instead of the calcium ion increased removal efficiency (%) of fluoride and phosphate ions to 92% and 97% at 48 h, respectively. This was ascribed to alkaline condition of pH higher than 8 due to the solution of CaCO₃, accelerating fluorine-containing apatite formation. With a mixture of calcium ion and scallop shell powder, high removal efficiency at the initial stage was obtained as opposed to the gradual increase with only scallop-shell, suggesting that an induction period of reaching sufficient concentration of calcium ion for apatite formation existed. These results showed that scallop shells were a promising material for simultaneous removal of phosphate and fluoride ions in waste water from e.g. electronic device plants.

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The mechanism of the burning side reaction in the INVISTA oxidation process is complex, nearly unknown, and difficult to model. In this study, a radial basis function neural network (RBFNN) was used to model the burning side reaction based on the data collected from the INVISTA process. Over the past decades, clustering methods have been used to improve the ability of several RBFNN models to determine more efficient structures. However, these RBFNN models determine the RBFNN structure without considering the prediction accuracy of the model. To elucidate the optimal RBFNN structure and obtain a satisfactory burning side reaction model, RBFNN integrated with partial mutual information-least square regression (PMI-LSR) is proposed. PMI-based selection takes the correlation between the hidden layer and the output layer into account and eliminates redundant information in the selected hidden layer neurons to improve RBFNN prediction accuracy. Sammon’s nonlinear map is used to illustrate the distribution of the selected hidden layer centers. This distribution differs from the uniform distribution of the cluster centers obtained using cluster methods. The burning side reaction model developed by PMI-LSR-RBFNN is better than those obtained by several cluster based RBFNN variants.

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The present study investigates the impact of post annealing of TiO₂ nanoparticulate films on their crystallinity, mechanical strength, and morphology. Non-agglomerated and amorphous TiO₂ nanoparticles of 46 nm diameter were synthesized in a plasma field, and were subsequently deposited on substrates to form nanoparticulate films. The films were annealed at various temperatures in the range of 100–1,200°C. Phase transformations from amorphous-to-anatase and from anatase-to-rutile were observed at 400°C and at 1,000°C, respectively. The high rutile transformation temperature was considered to be due to a tensile field induced by shrinkage of the film. The as-deposited film and the films annealed at below 400°C had poor mechanical strength. Conversely, the films annealed at over 500°C were strengthened by necking of the nanoparticles. The size of nanoparticles changed with increasing temperature. Annealing at 100–300°C caused the nanoparticles to shrink to approximately 30 nm. The nanoparticle diameters changed only slightly when annealed at 400–600°C because the annealing time was insufficient for changes to manifest. Annealing at 700–900°C caused the nanoparticle diameter to increase to approximately 50 nm because of sintering and coalescence of the nanoparticles. The diameter of the nanoparticles annealed at over 1,000°C became approximately 200 nm because of densification during the anatase-to-rutile transformation. The porosities of the films annealed at below 900°C were over 80%. However, the porosities of the films annealed at over 1,000°C decreased significantly due to densification.

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Diffuser films are key components in the backlight unit of a liquid crystal display and function as the light unifier. A heterogeneous coating solution containing solid poly(methyl methacrylate) beads, liquid acrylic resin and methylethylketone (MEK) is coated on the poly(ethylene terephthalate) substrate using a 1,700 mm wide reverse mode gravure coater and the diffuser films are thereafter prepared after drying. Depending on the bead concentration and size distribution in the coating solution, the resulting films are appropriate as the top diffuser films, the bottom diffuser films and the spacing films. The results show that with a coating width of 1,700 mm, a varying and narrow range of stable web-to-roll speed ratios is found for the reverse mode gravure heterogeneous coating system. While streaking defects are observed at high web-to-roll speed ratios, cascading defects occur at low web-to-roll speed ratios. When the viscosity of the coating solution decreases from 21 to 8 mPa·s, the gravure cell pick-out fraction decreases from 0.75 to 0.25. An empirical equation is developed to predict the stable operating web-to-roll speed ratio.

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The utilization of cattle manure as a blended fuel of pulverized coal fired plant has advantage to both solve waste disposal problems and comply with Renewable Portfolio Standard (RPS) law in Korea. Combustion possibility of cattle manure as a renewable biomass fuel was investigated by thermogravimetric analysis (TGA), 100 kg/h test furnace and ignition temperature (IT) tester through blending of cattle manure to design coal, Carbo bituminous coal. This study included the fuel characteristics (chemical composition, grandability), combustion reactivities (activation energy, kinetic rate constant, ignition temperature, temperature distribution in furnace, combustion efficiency) and slagging characteristics (mineral composition, fusion temperature, slag deposition rate, crystals formation). Thermogravimetric analyses (TGA) performed on Carbo coal, cattle manure, 2.5–40% Blends of cattle manure reveal that cattle manure will start devolatilization at 178°C which is about 78°C lower than 256°C of Carbo coal. Activation energy and kinetic rate constant of Carbo coal were 34.7478 kJ/mol and 53,284 s⁻¹ whereas those of cattle manure were 9.6935 kJ/mol and 319,038 s⁻¹. In the cases of 5 and 20% Blends, the activation energies calculated was 23.8714 and 16.4051 kJ/mol, respectively. The activation energy of samples decreased and combustion rate constant was greatly increased with increasing the blending ratio of cattle manure. The experiments of various Blends at 100 kg/h furnace showed that the combustible matters of more than 99.21% burns more completely in the boiler, due to the high surface area, oxygen functional groups (C–O, C=O, and O–C=O) and volatile matter contents in cattle manure. It showed that combustion starting temperature is lowered, the start-up speed is fast, and slag deposit rate on the nearest probes from burner is increased with increasing the blending ratio of cattle manure. The 20% Blends resulted in almost 22 times the slag deposition rate on the nearest probes from burner compared to Carbo coal and ash deposits on probes tubes that were more difficult to remove than other deposits. The increased slagging behavior with blends is probably due to the higher ash loading and alkali mineral composition of cattle manure. Although cattle manure has the high combustion efficiency, it was not appropriate as a single pulverized fuel of a coal fired plant because its Hardgrove grindability index (HGI), ignition temperature (IT) and initial deformation temperature (IDT) of about 35,232 and 1,100°C were too low to cause the shutdown, the spontaneous ignition at pulverizer, and the slagging in furnace. It was therefore proposed that the combustion of blends of cattle manure with less than 10% was the most appropriate for the prevention of pulverizing troubles, slagging and spontaneous ignition at the pulverized coal fired boilers, and, has the excellent combustion efficiency.

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The combustion properties of biomass can be improved via torrefaction. In this work, the effect of torrefaction on combustion properties of pine sawdust (PS) was investigated. The torrefaction conditions for PS were at 523 K for 40 min and 551 K for 15 min, respectively. Raw pine sawdust (RPS) and torrefied pine sawdusts (TPS) were selected to undergo combustion in a thermogravimetric analyzer at four different heating rates. Pretreatment by torrefaction reduced the temperature range of TPS during the volatile release process. A non-isothermal thermogravimetric method was used to evaluate the combustion kinetics through a model-free method. The activation energy analysis based on the Flynn–Wall–Ozawa method showed that the decomposition of more hemicellulose in the torrefaction process contributed to the higher activation energy in the early stage of TPS combustion process. The reaction order was calculated by the Avrami theory, and the results indicated that the least thermally stable sample TPS_551-15 had the highest reaction order.

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