Editor-in-Chief
Takao Tsukada (Tohoku University)

Associate (Editor-in-Cheifs)
Manabu Shimada (Hiroshima University)
Masahiro Shishido (Yamagata University)

Editors
Ryuichi Egashira (Tokyo Institute of Technology)
Jun Fukai (Kyushu University)
Choji Fukuhara (Shizuoka University)
Toshitaka Funazukuri (Chuo University)
Takayuki Hirai (Osaka University)
Jun-ichi Horiuchi (Kitami Institute of Technology)
Eiji Iritani (Nagoya University)
Yoshinori Itaya (Gifu University)
Noriho Kamiya (Kyushu University)
In-Beum Lee (Pohang University of Science and Technology (POSTEC))
Kouji Maeda (University of Hyogo)
Hideyuki Matsumoto (Tokyo Institute of Technology)
Nobuyoshi Nakagawa (Gunma University)
Masaru Noda (Fukuoka University)
Hiroyasu Ogino (Osaka Prefecture University)
Mitsuhiro Ohta (The University of Tokushima)
Eika W. Qian (Tokyo University of Agriculture and Technology)
Yuji Sakai (Kogakuin University)
Noriaki Sano (Kyoto University)
Naomi Shibasaki-Kitakawa (Tohoku University)
Ken-Ichiro Sotowa (The University of Tokushima)
Hiroshi Suzuki (Kobe University)
Nobuhide Takahashi (Shinshu University)
Shigeki Takishima (Hiroshima University)
Yoshifumi Tsuge (Kyushu University)
Tomoya Tsuji (Nihon University)
Da-Ming Wang (National Taiwan University)
Takuji Yamamoto (University of Hyogo)
Yoshiyuki Yamashita (Tokyo University of Agriculture and 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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Intra- and inter-molecular potential parameters have been newly derived to calculate the density and the self-diffusion coefficients of benzene, cyclohexane and their mixtures by molecular dynamics (MD) simulation using a six-center Lennard–Jones model. First, the validity of new parameters was examined in comparison with the reference experimental densities of pure components. Then, these parameters were adopted to the simulation of a benzene and cyclohexane mixture. Since simple combining rules (Lorentz–Berthelot) underestimated the density of the mixture, a concentration–dependent interaction parameter was newly introduced to predict the density of the mixture. The agreement between the experimental data and the simulated self-diffusion coefficients of benzene and cyclohexane in their mixture were improved by introducing the concentration–dependent interaction parameter.

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Biomass gasification is a promising technology for the utilization of biomass. In this study, a mathematical model for biomass gasification in dual fluidized bed (DFB) has been developed. The fluidized bed with biomass gasification was simulated as a bubbling fluidized bed, which was further divided into a bubble phase and an emulsion phase for modeling. The modeling results were compared with the experimental data to be in high agreement. The influences of steam to biomass mass ratio (S/B) and gasification temperature on the performances of the product gas concentration, the CO/H₂ and CO₂/CO molar proportions were focused on.

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We have developed a technology for producing nonagglomerated nanoparticles by causing collisions of the agglomerates in supersonic flows. To form these nonagglomerated nanoparticles, we conducted three experiments: the collision of agglomerated particles in a supersonic flow with a metal plate, the collision of agglomerated particles contained in two counter-current supersonic flows, and the collision of agglomerated particles in a supersonic flow with dry ice particles. The possibility that these collisions could fragment the agglomerates was investigated by measuring the size distribution of the agglomerates after the collisions using a differential mobility analyzer. Based on the experimental results, we propose that the most efficient technology for the fragmentation of the agglomerates depends on the concentration of the agglomerates. When the concentration is high, two counter-current supersonic flows containing the agglomerates should be used. When the concentrations are low, collision of agglomerates with dry ice particles should be performed.

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The effect of the pretreatment of ultrasonic irradiation on the deliquoring properties in expression was investigated by using carrots as an example of vegetables. The results indicated that the ultrasonic pretreatment produced a noticeable improvement in deliquoring behaviors such as the deliquoring rate and cake moisture content due to the physical damage of cell tissue, although the carrots were maintained in the original shape before and after ultrasonic irradiation. The time variation of the cake moisture content during the course of expression was well described by the three-stage creep model combined with the modified Terzaghi model. It was necessary to heat carrots above 50°C during ultrasonic irradiation in order to attain a desired effect in expression since carrots lost cell turgor pressure rapidly through β-elimination reaction occurring at about 50°C. The ultrasonic pretreatment was well evaluated from the viewpoint of the ultrasonic energy dissipated in the sample. The cake moisture content after 24 h from the beginning of expression dramatically decreased from 69 to 47% by increasing the pressure from 0.5 to 10 MPa, indicating that the cake consisting of treated carrots behaved as the compressible material in the expression operation.

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This paper proposes a novel method to accurately estimate the multivariate location and scatter for detecting outliers in the high-dimensional and complex contaminated data. Firstly, the abnormal degree of corresponding sample is characterized by a gamma index based on k-nearest neighbors. The smaller gamma index indicates the smaller distances from the sample to its neighbor samples and the higher probability for it to be a normal sample, while the higher probability to be an outlier. Secondly, based on the gamma index, a quasi-modified robust scaling is proposed to select the sub-sample data including the maximum normal data from the sample data. Continuing, the robust Mahalanobis distances are calculated based on the location and scatter of the sub-sample data and employed to distinguish between the normal data and outliers in the sample data. Finally, the proposed method is evaluated by using synthetic data, some standard benchmark data and a real industrial process data. The results show that the location and scatter of the sample data are calculated precisely and the outliers can be effectively detected and eliminated by the proposed method, which demonstrates its satisfactory ability to identify outliers and good prospect of application for chemical process data.

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This study presents an artificial neural network (ANN) approach for the modeling and control of the Fischer–Tropsch synthesis (FTS) slurry reactor. Operating data collected from an FTS demonstration plant were used to develop a radial basis function neural network (RBFNN) model, which is used for predicting the reactor temperature under industrial operation conditions. Additionally, a modified PID neural network (MPIDNN) control method was proposed for the reactor temperature control based on the trained RBFNN model. The differential evolution (DE) algorithm was used as the learning algorithm to automatically optimize the RBFNN and the PIDNN parameters. In the FTS slurry reactor simulation, the RBFNN model achieved satisfactory predictions of the reactor temperature, whereas the MPIDNN control system demonstrated an impressively stable and rapid control of the reactor temperature.

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Heme iron preparation (HIP) is a complex comprising heme iron and peptide fragments formed by enzymatic hydrolysis of hemoglobin. This complex was enriched by ultrafiltration and in heme-iron and is assumed to be water-soluble. In the present study, HIP was prepared using the blood of cultured yellowtail fish (fish-HIP) as a novel nutritional supplement. This method of preparation eliminated the need for mammalian sources. The optimal pH required for preparation of hydrophilic fish-HIP, with apparent water solubility similar to that prepared from bovine hemoglobin, was determined. An aqueous solution of fish-HIP was fractionated by centrifugation followed by filtration using membrane and ultrafilters. Dynamic light scattering and ultraviolet-visible light spectroscopy demonstrated that fish-HIP was present in the hydrocolloidal form in aqueous media, with a particle size of 80–100 nm. This is the first report that demonstrated the hydrocolloidal nature of HIP. High-performance liquid chromatography (HPLC) and mass spectroscopy showed that the peptides in fish-HIP are more hydrophobic than those separated by ultrafiltration and have molecular weights ranging from 2,000 Da to 3,600 Da.

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The present study investigates silica coated ZnO prepared by microwave-assisted sol-gel method from tetraethoxysilane (TEOS) and commercial ZnO nanoparticles, and further treated with 3-aminopropyltriethoxysilane (APTES) to change the surface characteristics. For the silica coating of ZnO nanoparticles in a batch type microwave apparatus, two kinds of TEOS/ZnO starting ratios (=0.3, 0.5) were used. The transmission electron microscope (TEM) images of coated samples with different TEOS/ZnO starting ratios suggested that uniform silica coating on the ZnO surface was observed for the coated sample with a TEOS/ZnO ratio of 0.5; whereas, the ZnO surface was partly exposed on the sample with a TEOS/ZnO ratio of 0.3. When these silica coated ZnO nanoparticles were used as starting materials for APTES treatment, it was revealed that 5 wt% (=APTES/silica coated ZnO) of APTES loading was enough to change the dispersion property of the sample with a TEOS/ZnO ratio of 0.5 in the organic solvent/water system. On the contrary, a higher APTES loading amount (10 wt%) was needed for the sample with a TEOS/ZnO ratio of 0.3 to observe the same phenomenon. The results of TEM observation, Fourier Transform Infrared (FT-IR) analysis, and Zeta potentials for the coated samples supported the results of dispersion tests in the organic solvent/water system. Photo-catalytic activities of the samples with a TEOS/ZnO ratio of 0.5 kept at low level (less than 5% compared to bare ZnO) with increasing APTES loading amounts. In contrast, those of the samples with a TEOS/ZnO ratio of 0.3 were reduced with increasing APTES loading amounts.

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Poly(ethylene naphthalate) (PEN) pellets were converted to monomers (naphthalene dicarboxylic acid (NDC) and ethylene glycol (EG)) in an aqueous amine solution under hydrothermal conditions using a small semi-batch reactor. Three amines (methylamine, dimethylamine, and trimethylamine) were evaluated as reactants for depolymerization of PEN and compared with ammonia. The total yield of both monomers (NDC+EG) on the basis of the carbon mass of the initial PEN pellets, at 493 K and 5.0 MPa, for a reaction time of 50 min, using an amine concentration of 0.6 mol/kg was highest with trimethylamine (97.2%) followed by methylamine (86.6%) and dimethylamine (89.8%) in succession. The differences in the total yields resulted primarily from the differences in the NDC yields, and were affected by the amine species, although the EG yield was similar with all amines. The yields were higher than 95% of the theoretical value with all evaluated amines. The difference in the yields may be affected by the stabilities of the intermediate products with the primary and secondary amines in the aqueous solutions. The reaction rates with respect to the unreacted mass of PEN were represented by the surface reaction model, i.e., 2/3rd order reaction kinetics, as previously observed for poly(ethylene terephthalate) in aqueous solutions of ammonia and amine at low concentrations. The apparent rate constant from the surface reaction model was proportional to the amine concentration.

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