Editor-in-Chief:
Hiroyuki Honda (Nagoya University)

Associate Editors-in-Chiefs:
Manabu Shimada (Hiroshima University)
Takao Tsukada (Tohoku University)

Editors:
Ryuichi Egashira (Tokyo Institute of Technology)
Jun Fukai (Kyushu University)
Choji Fukuhara (Shizuoka University)
Takayuki Hirai (Osaka University)
Masahiko Hirao (The University of Tokyo)
Jun-ichi Horiuchi (Kitami Institute of Technology)
Eiji Iritani (Nagoya University)
Yoshinori Itaya (Gifu University)
Hideo Kameyama (Tokyo University of Agriculture and Technology)
Masahiro Kino-oka (Osaka University)
Toshinori Kojima (Seikei University)
In-Beum Lee (Pohang University of Science and Technology (POSTEC))
Shin Mukai (Hokkaido University)
Akinori Muto (Osaka Prefecture University)
Nobuyoshi Nakagawa (Gunma University)
Hiroyasu Ogino (Osaka Prefecture University)
Naoto Ohmura (Kobe University)
Mitsuhiro Ohta (Muroran Institute of Technology)
Hiroshi Ooshima (Osaka City University)
Yuji Sakai (Kogakuin University)
Noriaki Sano (Kyoto University)
Masahiro Shishido (Yamagata University)
Richard Lee Smith, Jr. (Tohoku University)
Hiroshi Suzuki (Kobe University)
Shigeki Takishima (Hiroshima University)
Yoshifumi Tsuge (Kyushu University)
Da-Ming Wang (National Taiwan University)
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

抄録全体を表示

This article discusses the directions for energy systems based on an urgent proposal to counter the energy crisis in eastern Japan, published from the Society of Chemical Engineers, Japan. We first illustrate the situation Japan faces, highlighting the urgency and seriousness of the consequences of power outages in industry and daily life. Then, we elaborate on the necessity for policy support to trigger collective actions to temporarily practice countermeasures that would not necessarily save resources or that could disrupt society's established routines. In this way, Japan can choose technologies without regret based on society-wide discussions on the future energy supply. Finally, we warn of the drawbacks induced by shortsighted decisions e.g., avoiding power outages by depending on less-efficient gas turbines. We conclude that Japan should commence a transition of its energy systems rather than compromising resource efficiency and grid robustness over the next decades.

抄録全体を表示

The pharmaceutical industries are undoubtedly experiencing a series of challenges. One of these is the administration of solid form of many drugs due to many well known drawbacks including low solubility, polymorphic conversion and low bioavailability. Such problems are further aggravated when drug molecules or starting materials for synthesis of drugs are insoluble or sparingly soluble in aqueous media and most of pharmaceutical acceptable organic solvents. To overcome these problems, some times, highly polar organic solvents including pyridine, dimethylformamide (DMF) and N-methylpyrrolidone (NMP) which are not considered as environmental benign solvents have been used. These restrictions demand superior solvent systems and/or new drug forms that can be used as reaction media to avoid volatile organic solvents and/or as new forms of drugs. Much effort is being invested in such approaches to find new delivery technologies or development of new controlled-release dosage forms. In recent years, ionic liquids (ILs) that are salts of low melting point and consist only of ions have been increasingly exploited as solvents and/or (co)solvents and/or reagents in a wide range of pharmaceutical applications due to their tailor-made chemical, physical and biological properties. Studies have shown that ionic liquid-assisted drug carrier or active pharmaceutical ingredients (APIs) synthesized as IL form or many drug compounds produced using ILs as reaction media provide many unique and attractive properties compared to conventional counterparts. Furthermore, ILs could be employed as potential antimicrobial agents for various microorganisms. The aim of this article is to summarize the efforts placed on using ionic liquids in pharmaceutical applications.

抄録全体を表示

The cost of solar-grade silicon cannot be reduced in the Siemens process, which is the major process of producing polycrystalline silicon through current technologies. Therefore, the zinc reduction process, which can reduce solar-grade silicon in a cost effective manner, should be redeveloped for these conditions. The thermodynamics in the zinc reduction process are studied in this paper. When the reactions reach equilibrium, the equilibrium gas phase composition has been analyzed within the temperature range of 1184 to 1500 K at n_SiCl4/n_Zn of 1/2, 1/4, 1/8 and P = 1 atm, 3 atm and 6 atm. Furthermore, the relations of the production ratio of silicon and pressure, temperature and the feed molar ratio (n_Zn/n_SiCl4) are investigated and the graphs thereof are plotted. The major side-reactions affecting the production ratio of silicon have been established as: SiCl₄(g) + Zn(g) → SiCl₂(g) + ZnCl₂(g) and SiCl₄(g) + Si(s) → SiCl₂(g). Finally, suitable operational conditions in the practical process of poly-silicon manufacture have been established, with 1200 K, 2 atm and the feed molar ratio (n_Zn/n_SiCl4) of 4 at the entrance is the best conditions. A production ratio of silicon of 90.3% is achieved under these conditions. Furthermore, 1184 K, 2 atm and the feed molar ratio (n_Zn/n_SiCl4) of 4 are the ideal conditions. Under these conditions, the theoretical yield is 98%.

抄録全体を表示

The flow generated in a stirred tank of 0.48 m diameter, agitated by three impellers of 0.19 m diameter, including one half-elliptical blade disc turbine (HEDT) below and two up-pumping wide-blade hydrofoils (WH_U), were investigated by using 360° ensemble-averaged particle image velocimetry (PIV) technique. The flow characteristics for seven impeller combinations with different impeller spacings were investigated. Results show that global circulation patterns in the stirred tank are strongly dependent on the impeller spacing. Three types of flow patterns were observed, including five, four, and three circulation loops in the flow field, by changing the spacing between the bottom and the middle impellers (C₁), the spacing between the middle and the top impellers (C₂), and the submersion depth of the top impeller (C₃). While the clearance (ΔC) of the bottom impeller is equal to 0.4T, the five circulation loops flow pattern occurs when C₁ = 0.48T, C₂ = 0.48T, and C₃ = 0.4T, and the four circulation loops flow pattern occurs when C₁ = 0.48T, C₂ = 0.4T, and C₃ = 0.4T, and the three circulation loops flow pattern occurs when C₁ = 0.48T, C₂ = 0.4T, C₃ = 0.32T. The mixing efficiency defined based on the mixing time and the power consumption were also discussed and the results show that less circulation loops could lead to higher mixing efficiency, but the mixing efficiency does not solely increase with the decreasing of the circulation loops.

抄録全体を表示

The purpose of the present study was to enhance the classification performance of electrical field-flow fractionation (EFFF). In recent research by this group, the surface potential of silica particles treated with a bead mill displayed size dependency—smaller particles had a more negative zeta potential. This phenomenon and the EFFF system were used to classify the particles, with the bottom and top plates of the EFFF channel serving as negative and positive electrodes, respectively.
In the present study, improvements to the EFFF channel were carried out to enhance classification accuracy. Walls of deionized water were utilized to prevent particles from contacting the electrodes. Because vertical electrophoresis led to the disturbance of particle trajectories in the channel by gravitational sedimentation, horizontal electrophoresis was applied. Furthermore, hydrodynamic force was induced in the channel creating differing linear velocities of the slurry and the water at the inlet. As a result, 200-nm particles could be classified at an applied voltage of 5 V with high accuracy when compared with the previous method that used vertical electrophoresis.

抄録全体を表示

The evaluation of density and micro-void defects of ε-HNIW crystals was investigated in the drowning-out crystallization. Also, methods to quantitatively evaluate the crystal void defects were developed by using pycnometer and differential scanning calorimeter. Since the ε-HNIW crystals were re-constructively transformed from β-HNIW, which was crystallized out by drowning-out crystallization, the density and defect of ε-HNIW crystals were predominantly determined by the growth process during the phase transformation. Due to contradictory contributions of crystallization conditions on crystal defects, the crystal density was maximized at around the anti-solvent feeding time of 120 min and temperature of 25°C within ranges of the anti-solvent feeding time and temperature from 0–180 min and 5–30°C, respectively. Based on comparison of the measured crystal density with ideal one (2.044 g/cm³), the void defects of crystals were estimated. In addition, the thermal energies related with the solid-state phase transition from ε-HNIW to γ-HNIW and decomposition of HNIW were indicated to successful quantification of crystal defects owing to the significant changes of the thermal energies with the crystal density. Using the X-ray microscopic analysis with 80 nm resolution, it was proven that the micro-void defects in the crystal existed obviously to cause the change of crystal density and thermal properties.

抄録全体を表示

Arsenic in groundwater poses a health hazard for rural areas all over the world, especially in developing countries. This paper reports the findings of a batch study performed to identify the best possible method for the preparation of an adsorbent for arsenic removal from groundwater. The study also includes the effects of column parameters on the removal of arsenic. The results show that laterite, because of its high iron content, has promising applications in arsenic treatment. Batch experiments for the adsorption of arsenic on laterite calcined at different temperatures were performed to identify the appropriate conditions for the preparation of the adsorbent. Laterite calcined at 400°C could remove 99.42% of arsenic from simulated groundwater, and thus, the treated water met the WHO standard for drinking water. Characterization of the calcined laterite by XRF, EDX, XRD, BET, and SEM analyses confirmed the successful adsorption of arsenic by laterite. The adsorption equilibrium was determined by varying the initial arsenic concentration from 0.361 to 5.073 mg/L in the batch experiments. The Langmuir and Freundlich isotherm models supported the experimental data. The effect of various column operation parameters such as space velocity, inlet arsenic concentration, and adsorbent bed height on the column performance was investigated. The BDST model was also useful in predicting the column parameter constants. In summary, it was demonstrated that calcined laterite is a low-cost adsorbent that is effective and suitable for the arsenic treatment of groundwater.

抄録全体を表示

Combustion possibility of upgrade ECO coal as a blended fuel of commercially thermal power plant was investigated by thermogravimetric analysis (TGA), drop tube furnace (DTF) and ignition temperature (IT) tester. TGA results showed that combustion patterns of coal samples has the simultaneous devolatilization and oxidation reactions, and the fixed carbon contained with minor content in high moisture ECO coal (HM ECO) was slowly burned to high temperature than it of dry ECO coal (Upgrade ECO) due to heat loss of moisture evaporation. The linear regression for the Arrhenius plot to the experimental data is very good, and activation energies for overall combustion of bituminous C & A (Design C & A) and Upgrade ECO are 66.83 and 29.64 kJ/mol, respectively. It was derived that activation energies of 30%, and 50% Blends produced through mixing of Upgrade ECO of 30%, and 50% to Design C & A are 31.44 and 29.98 kJ/mol in reciprocal proportion to blending ratio. Test results show that the volatile content contained in coal samples area significantly improved the combustion reactivity. The conversion behavior of the coals observed in DTF was similar to that reflected in TGA. DTF studies showed that the combustion of all blends was also completed at residence time of around 1 second, set temperature range of 1,200°C similar to commercial coal fired plant. Although the Upgrade ECO has the highest conversion than the blends, it was not appropriate as the single pulverized fuel of coal fired plant because its initial deformation (IDT) and ignition temperatures of about 1,090 and 215°C, respectively, were too low to cause the slagging in boiler, and the firing at pulverizer. The IDT of the blends ashes of Upgrade ECO of less than 30% was about 1,250°C, and, was not expected to be associated with slagging and fouling in pulverized coal fired systems. The liability of spontaneous combustion of coal samples was increased with increasing the moisture and volatile contents whereas it of Upgrade ECO was the highest due to the high volatile content and thermal diffusivity. It was therefore proposed that the combustion of blends of Upgrade ECO with less than 30% was the most appropriate for the prevention of slagging and spontaneous combustion at the pulverized coal fired boilers, and, has the excellent combustion efficiency.

抄録全体を表示

5-Hydroxymethylfurfural (5-HMF) is one of the intermediates in char polymerization, a side reaction that occurs in the supercritical water gasification (SCWG) of biomass. In this paper, we report the kinetic investigation of the polymerization of 5-HMF during solid char formation in an acidic environment. This is due to the fact that 5-HMF coexists with other product acids during biomass decomposition. Mixtures of 5-HMF and HCl were treated under subcritical conditions (350°C; 25 MPa). The concentration of 5-HMF ranged from 0.01 to 0.05 M, while that of HCl was 0.01 M (at room temperature). The rates of gas and char production from 5-HMF in experiments with and without acid addition were compared. The acid catalyzed the gasification and polymerization pathways of 5-HMF, especially the decomposition of 5-HMF to TOC, the rate constant of which was increased by two orders of magnitude.

抄録全体を表示

A dynamic model describing the behavior of a multi-cylinder paper drying processes is developed based on the mass and heat balances around drying cylinders. The multi-cylinder model is an expansion of a single cylinder model coupled with the behavior of the paper web and the felt. The balance equations consist of sets of differential equations describing heat and mass transfer around the canvas, the web and the drying cylinders. The values for the cylinder temperatures and moisture contents are estimated and compared with operating data. In order to obtain further information for energy consumption generation of entropy at each drying cylinder is investigated based on the model developed.

抄録全体を表示