JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
Print ISSN : 0021-9592
Volume 36 , Issue 2
Showing 1-15 articles out of 15 articles from the selected issue
Transport Phenomena, Fluid Mechanics and Mixing
  • Jianxing Zheng , Kunio Kataoka , Tokuo Yoshimura , Naoto Ohmura
    Type: Research Papers
    Subject area: Transport Phenomena, Fluid Mechanics and Mixing
    2003 Volume 36 Issue 2 Pages 147-154
    Published: 2003
    Released: October 19, 2003
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    A submerged water jet impinging upon a free air-water surface has been investigated experimentally. The present work focuses on the dynamic deformation of the surface bump generated in the jet impingement region. The surface bump has a quake motion comprising two basic oscillations: fluttering motion (transversely) and swelling motion (vertically). The velocity measurement was made beneath the bump with hot-wire anemometry. The motion of the geometrical stagnation point was analyzed with the aid of an image processing. It has been ascertained that a helical instability of the approaching jet is the origin of the fluttering motion of the surface bump and that the swelling motion is controlled by the large-scale vortical/turbulent structure of the approaching jet convected with phase velocity.
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  • Noboru Otomo, Waldemar Bujalski, Alvin William Nienow, Koji Takahashi
    Type: Research Papers
    Subject area: Transport Phenomena, Fluid Mechanics and Mixing
    2003 Volume 36 Issue 2 Pages 166-171
    Published: 2003
    Released: October 19, 2003
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    Gas dispersion characteristics of a single impeller in a fully baffled cylindrical pilot scale stirred vessel (T = 0.72 m) were studied for newly developed impellers, which are a 6-bladed hollow blade disc turbine (6HB) and a Lightnin A315 (A315), in addition to the traditional 6-bladed Rushton disc turbine (6DT), under unarerated and aerated conditions in water. The power drawn, gas hold-up and kLa (oxygen mass transfer rate) obtained were compared with those for the 6DT reported in literature. As a result, it was found that the gas handling capacities of the 6HB and A315 are superior to that of the 6DT.
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  • Setsuro Hiraoka, Yutaka Tada, Yoshihito Kato, Yuichiro Murakami, Yusuk ...
    Type: Research Papers
    Subject area: Catalysis, Kinetics and Reactor Design
    2003 Volume 36 Issue 2 Pages 187-197
    Published: 2003
    Released: October 19, 2003
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    The discharge flow rate Qd for both paddle impeller and pitched blade paddle impeller were measured with the flow follower method. The discharge flow rate number obtained for the paddle impeller Nqd was correlated with the power number Np and the impeller dimensions, based on the correlation form derived from the angular momentum balance between the impeller tip and the vessel wall. The correlation of Nqd obtained for the paddle impeller was modified with the blade angle θ to give the correlation of Nqd for the pitched blade paddle impeller. The resultant correlations were

    (Nqd)NB = 0.14(D/d)1/2β[(D2H/d3)Np]1/2(3.3γnp0.7bsin1.6θ/H)θ/π
    for γnp0.7bsin1.6θ/H < 0.3


    = 0.14(D/d)1/2β[(D2H/d3)Np]1/2
    for γnp0.7bsin1.6θ/H > 0.3


    for a non-baffled vessel and

    (Nqd)B = 0.25(np0.7b/d)–1/4β[(D2H/d3)Np]1/2(2.5γnp0.7bsin1.6θ/H)θ/π

    for a baffled vessel, respectively. These correlations reproduced not only the present experimental results but also the results measured by other investigators within ±30% experimental error.
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Catalysis, Kinetics and Reactor Design
  • Eun-Ku Lee, Min-Woo Song, Hyun-Sik Hahm, Kyung-Lim Kim
    Type: Research Papers
    Subject area: Catalysis, Kinetics and Reactor Design
    2003 Volume 36 Issue 2 Pages 126-131
    Published: 2003
    Released: October 19, 2003
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    A two-stage CO2 hydrogenation reaction was conducted to increase methanol yield. At the first-stage, CO2 was converted to CO by the reverse water-gas shift reaction with Cu/ZnO/Al2O3, Fe2O3/Cr2O3, or MoS2/TiO2 catalyst, and then at the second-stage, methanol was synthesized from the effluents of the first-stage with a commercial methanol synthesis catalyst, Cu/ZnO/Al2O3. In the case of the two-stage CO2 hydrogenation reaction, CO that was produced by the first-stage reverse water-gas shift reaction contributed to the methanol synthesis, increasing the methanol yield. Especially, with the two-stage CO2 hydrogenation reaction, methanol yield obtained was two or three times higher than that of the single-stage one. It was found that to increase the methanol yield in the two-stage hydrogenation reaction, more CO2 should be converted to CO at the first-stage. The XRD patterns of the Cu/ZnO/Al2O3 catalyst before and after reaction showed the presence of metallic bulk Cu and the absence of other bulk Cu species.
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  • Shin-Ichiro Fujita, Yoko Sano, Bhalchandra M. Bhanage, Masahiko Arai
    Type: Research Papers
    Subject area: Catalysis, Kinetics and Reactor Design
    2003 Volume 36 Issue 2 Pages 155-160
    Published: 2003
    Released: October 19, 2003
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    Hydrogenation of cinnamaldehyde (CAL) with a ruthenium-triphenylphosphine complex was carried out under various conditions in several solvents such as N, N-dimethylformamide (DMF), 1-methyl-2-pyrrolidone (NMP) and ethyl acetate (AcEt). In this reaction, cinnamyl alcohol (COL), hydrocinnamaldehyde (HCAL) and hydrocinnamyl alcohol (HCOL) are formed. Among the solvents used, DMF gives the highest reaction rate and the highest selectivity for COL. The reaction order of the substrate consumption also changes with the solvent. The rate of CAL consumption is of the first order with respect to its concentration in DMF, while those in the other solvents are of the zeroth order. Hydrogenation of COL to HCOL was found to be negligible under the present reaction conditions. By simulation for the concentration–time profiles of the substrate and the products obtained in DMF, rate constants for the elemental reactions involved in the title reaction, i.e. the hydrogenation reactions of CAL to COL, of CAL to HCAL and of HCAL to HCOL, were determined. These rate constants increase linearly with H2 pressure below 4 MPa. Above this pressure, they remain practically constant. Effect of the ligand/metal ratio on these rate constants was also investigated.
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  • Shigeru Sugiyama, Hiromichi Mitsuoka, Tomotaka Shono, Toshihiro Moriga ...
    Type: Research Papers
    Subject area: Catalysis, Kinetics and Reactor Design
    2003 Volume 36 Issue 2 Pages 210-215
    Published: 2003
    Released: October 19, 2003
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    Although it is generally accepted that the catalytic activities of hydroxyapatites for the oxidative dehydrogenation of propane decrease upon addition of CCl4 into the feedstream, greater and stable activities have been found with copper-strontium hydroxyapatites (Cu-SrHAp) in the presence of CCl4. X-ray diffraction and X-ray absorption fine structure analyses of the catalysts used for the oxidation in the presence and absence of CCl4 demonstrate that deep reduction of Cu2+ to Cu0 of Cu-species in Cu-SrHAp during the oxidation is suppressed by the introduction of CCl4, resulting in an enhancement of the activities of the catalysts in the presence of CCl4.
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  • Yasuhiro Shiraishi, Takayuki Hirai, Isao Komasawa
    Type: Short Communications
    Subject area: Catalysis, Kinetics and Reactor Design
    2003 Volume 36 Issue 2 Pages 220-224
    Published: 2003
    Released: October 19, 2003
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    Polymer-supported sulfonium salt (PS) was synthesized by the reaction of sulfur-containing compounds, present in light oil, with iodomethylpolystyrene (IMP) and AgBF4. Dibenzothiophenes (DBTs) and benzothiophenes (BTs) in the oil were successfully anchored on the IMP as the corresponding sulfonium salts, via nucleophilic displacement of the iodide atom on IMP with the sulfur atom on DBTs and BTs. By this means, the sulfur content of the light oil was decreased successfully to the required deep desulfurization level (0.05 wt%). The PS, obtained from light oil, showed significantly high activity as phase transfer catalyst for the anion exchange reaction of 1-bromooctane with potassium thiocyanate in the organic/water two-phase system. This high activity for the PS results since the highly lipophilic alkyl-substituted DBTs and BTs are anchored on the PS as the sulfonium salts.
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Particle Technology and Fluidization
  • Jeong-Hoo Choi, Sang-Jin Ko, In-Yong Chang, Chang-Keun Yi, Do-Won Shun ...
    Type: Research Papers
    Subject area: Particle Technology and Fluidization
    2003 Volume 36 Issue 2 Pages 132-137
    Published: 2003
    Released: October 19, 2003
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    In order to understand the characteristics of slug coalescence, the slug frequency has been measured by a differential pressure method in a gas-fluidized bed of i.d. 0.1 m and height 2.25 m, at ambient temperature and pressure, and with respect to variations of bed height (0.23–0.93 m) and gas velocity (UUmf = 0.0190–0.139 m/s). Air was used as fluidizing gas and a fresh FCC catalyst (Geldart’s group A particle, dp = 0.070 mm, ρs = 1600 kg/m3, Umf = 0.0113 m/s) and glass bead (Geldart’s group B particle, dp = 0.168 mm, ρs = 2486 kg/m3, Umf = 0.0303 m/s) as bed materials.
    The slope of a frequency decrease accompanying with a gas velocity increase at different bed heights was similar in the bed of Geldart’s group-A particle. So was the slope of frequency decrease with bed height at different constant gas velocities. The mechanism controlling slug coalescence was found to be different between Geldart group-A and B particles. The slug coalescence model proposed by Yamazaki et al. (1984) was extended to the case with gas velocity as a variable. The slug coalescence rate constant leveled off after an initial decrease in the bed of Geldart’s group-B particle. However, it increased in the bed of Geldart’s group-A particle as the gas velocity increased. Correlation on the slug coalescence rate constant that includes effects of gas velocity, temperature and particle properties has been proposed in each different slug growth regime.
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Process Systems Engineering
  • Junghui Chen, Yuezhi Yea
    Type: Research Papers
    Subject area: Process Systems Engineering
    2003 Volume 36 Issue 2 Pages 198-209
    Published: 2003
    Released: October 19, 2003
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    Dynamic matrix control (DMC) has been widely applied in many industrial processes due to the simple design for multivariable process control. However, lack of the adaptability restricts its application in the highly nonlinear and complex processes. The nonlinear model predictive controller for processes is needed, but, from a computational perspective, it has quite comprehensive demands. In this paper, modified quadratic dynamic matrix control (MQDMC), which integrates DMC with the neural network model, is proposed. The predictive model control strategy linearizes the model by applying instantaneous linearization to the nonlinear neural network model at each sampling time. MQDMC has two advantages. First, less computation of linear DMC is used. Second, the nonlinear characteristics of neural networks can be incorporated into predictive control design. In the simulation studies, the performance of MQDMC matches that of nonlinear neural network model predictive control.
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Biochemical, Food and Medical Engineering
  • Koji Endo, Noboru Suzuki, Masato Hoshi, Masahide Sato, Teiji Kato, Ats ...
    Type: Research Papers
    Subject area: Biochemical, Food and Medical Engineering
    2003 Volume 36 Issue 2 Pages 138-146
    Published: 2003
    Released: October 19, 2003
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    For a detailed analysis of the water barrier function of skin, it is necessary to obtain effective physical parameters related to the rate of transepidermal water loss (TEWL). By using a modified ventilated chamber measurement system, with high sensitivity and response, we have determined the apparent mass transfer coefficient of water, K, for the stratum corneum (SC) and the water vapor pressure, Pd, at the interface between SC and underlying living cells of epidermis from analyses of water distribution in the contact zone of carrier gas and skin surface. By data fit optimization of the calculated water flux to the measured one, the in vivo K value for human skin was determined to be (0.30 ± 0.14) × 10–8 kg/(m2·s·Pa) (n = 4, mean ± SD) which is close to the corresponding in vitro value of (0.12 ± 0.02) × 10–8 kg/(m2·s·Pa) (n = 6, mean ± SD) for porcine SC membranes. It is, therefore, concluded that the apparent mass transfer coefficient of water for SC can be estimated in vivo and noninvasively by the method developed in this study and will lead to a more precise and reliable evaluation of skin barrier function than the rate of TEWL itself.
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  • Naofumi Shiomi, Yoko Inoue, Kanji Tomioka, Takako Yasuda
    Type: Research Papers
    Subject area: Biochemical, Food and Medical Engineering
    2003 Volume 36 Issue 2 Pages 161-165
    Published: 2003
    Released: October 19, 2003
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    Candida rugosa ATCC14830 cells have high tendency to make flocculent masses by entanglement of the mycelium-like shaped cells and can be well immobilized in porous polyvinyl formal (PVF) resin. Moreover, Candida lipolytica cells, which became to show a mycelium-like shape by mutation, were also immobilized in PVF resin.
    These C. rugosa and mutant C. lipolytica cells were immobilized in PVF resins and cultured by the draw-fill method 2–3 times. These C. rugosa and C. lipolytica cells could decompose L-lactic acid and produce bio-surfactant liposan, respectively. Because high cell densities could be attained in immobilized systems, the total productivity in repeated-batch operations with immobilized cells was higher than those in batch operations with free cells. Moreover, the decomposed amount of L-lactic acid did not decrease during the repeated-batch operations, because the number of immobilized cells in PVF resin was kept almost constant.
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  • Kenjiro Kano, Takaharu Hayashi, Toshihiro Komeda, Haruhiko Tsumura, Ke ...
    Type: Research Papers
    Subject area: Biochemical, Food and Medical Engineering
    2003 Volume 36 Issue 2 Pages 172-177
    Published: 2003
    Released: October 19, 2003
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    Purification of recombinant cathepsin C (CTC) from the fermentation broth of methylotrophic yeast, Candida boidinii was conducted. After centrifugation, fermentation supernatant was processed with four consecutive chromatography columns (cation exchange, hydrophobic, anion exchange, and gel filtration). As a result, the recombinant CTC of 4.7 U/mg was purified from the fermentation broth containing 169 U/l of CTC and the yield was 35%. From the gel filtration analysis, molecular weight of the recombinant CTC was determined to be about 200 kDa, that was almost the same as the native one. From SDS-PAGE analysis and N- terminal amino acid analysis, the monomer bands of the recombinant CTC were discussed. In order to compare the enzymatic property of the recombinant and native CTC, (1) pH profile of the activities, (2) temperature profile of the activities, and (3) enzymatic specificity for several substrates were investigated. From these studies, it was revealed that the enzymatic property of the recombinant CTC was almost the same as that of the native one.
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Safety, Environment and Energy
  • Dzevo Alibegic, Satoshi Tsuneda, Akira Hirata
    Type: Research Papers
    Subject area: Safety, Environment and Energy
    2003 Volume 36 Issue 2 Pages 178-186
    Published: 2003
    Released: October 19, 2003
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    Chlorinated volatile organic compounds (CVOCs) such as tri- and tetrachloroethylene (TCE and PCE) are common contaminants of ground water and soil. Numerous studies have been carried out with the long-term objective of the development of efficient, destructive on-site technologies for their removal. The so-called advanced oxidation processes (AOPs) were applied in the liquid and in the gas, but were shown to have limited application. In the liquid phase the efficiency was limited due to the presence of OH radical scavengers and UV light absorbers; and in the gas phase due to the production of stable intermediates.
    A new photochemical reactor system is described, in which the polluted air (from the air stripper or SVE unit) is absorbed into a bubble column reactor equipped with the UV light (UV-BCR) containing only distilled water and H2O2 as a reacting medium. The experiments showed that the oxidation of model pollutant PCE in a liquid phase occurred approximately 6 times faster in an OH radical scavenger-free environment compared to the experiments in which the OH radical scavenger concentration was adjusted to a level usually found in ground waters. It was also observed, that for the certain PCE concentration, there exists an optimal hydrogen peroxide concentration above and below which the rate is reduced and could be predicted by the kinetic model under operational conditions of this work. For the experiments in which PCE gas was absorbed into the UV-BCR, the influences of the two critical parameters, gas flow rate and the hydrogen peroxide concentration, were investigated using the experimental design methodology. There has been observational evidence of the efficiency of the process (cca 75%–80% PCE gas removal efficiency in one flow through the UV-BCR) but the operational parameters still need to be optimized.
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  • Takako Yasuda, Shigeo Katoh, Yoko Inoue, Naofumi Shiomi
    Type: Short Communications
    Subject area: Safety, Environment and Energy
    2003 Volume 36 Issue 2 Pages 216-219
    Published: 2003
    Released: October 19, 2003
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    We proposed a novel bioremediation method, bioremediation by the self-immobilization system (BSIS), for application to treat pollution of soil spreading over a wide area. In this method, cells are immobilized by spontaneous formation of aggregates and retained in soil. We selected B. subtilis IFO3335 strain, which secretes viscous filaments and forms strong aggregates, as one of strains suitable for this bioremediation method based on self-immobilization, and studied their behavior in soil. These cells could be retained at a shallow layer under soil for a long period.
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General Research and Others
  • Yoshihiro Tomita, Tadahiro Morifuji, Manabu Tomisaka, Masahiro Sunohar ...
    Type: Research Papers
    Subject area: General Research and Othres
    2003 Volume 36 Issue 2 Pages 119-125
    Published: 2003
    Released: October 19, 2003
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    The electroless tin-plating on copper has the preferable characteristics for the thermal compression bonding, although it is easy to decrease in thickness by heating at the bonding because of the diffusion with copper.
    Therefore, the bonding profile was determined to have lower pre-heating to evaluate the bondability with copper-bumps dressed thin tin-caps in 20 μm-pitch. Then, the possibility of the interconnections in 20 μm-pitch was confirmed. Bonding temperature was 150°C and bonding force was 24.5 N.
    Finally, the tin-cap on a through-hole electrode (T-COTE) was performed in the electroless plating and the basic bonding condition was evaluated on the vertical interconnections.
    The results showed the sufficient joint between the copper electrodes through the Si die and the adjacent copper bumps on the interposer.
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