JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
Online ISSN : 1881-1299
Print ISSN : 0021-9592
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Volume 25, Issue 5
Displaying 1-27 of 27 articles from this issue
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Review Paper
  • Transport Phenomena in Membrane Separation Processes
    Shoji Kimura
    1992 Volume 25 Issue 5 Pages 469-480
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.469
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    Transport phenomena in various membrane separation processes, such as dialysis, reverse osmosis, ultrafiltration, microfiltration, pervaporation, and vapor permeation, were reviewed. Transport equations that are necessary to analyze experimental data and to obtain transport coefficients are explained. Some transport mechanisms were discussed. Also, the relation between reverse osmosis, pervaporation and vapor permeation was explained. Finally, recent topics about new membranes were introduced.
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Original Papers
  • Analysis of the Formose Reaction System
    Takashi Niitsu, Masato M. Ito, Hakuai Inoue
    1992 Volume 25 Issue 5 Pages 480-485
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.480
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    A kinetic analysis of the formose reaction, a calcium hydroxide-catalyzed condensation of formaldehyde to carbohydrates in aqueous homogeneous media, was carried out and the performance of the reaction was studied on the basis of a dynamic treatment of the complex reaction system taking into consideration all the species expected to be formed from formaldehyde. The analytical results were compared with the kinetic characteristics experimentally observed. It was found that the carbonyl rearrangement and retro-aldol reaction steps played a substantial role in the autocatalytic nature of the formose reaction. The rates of these reactions were found to be large and the product distribution stayed nearly in equilibrium. The calculated results showed good agreement with the experimental ones, assuming that the species which can afford the foranose or pyranose ring become much less reactive in the subsequent reactions.
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  • Characteristics of Policy- and Experience-Driven Neural Network when Applied to Level Control
    Masaru Ishida, Jixian Zhan
    1992 Volume 25 Issue 5 Pages 485-489
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.485
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    The characteristics of the PENN (Policy- and Experience-driven Neural Network) controller were examined by applying it to water-level control. This controller is driven by two learning mechanisms: (1) global learning based on control policy and (2) local learning based on previous experience. The applicability of the PENN controller was tested by simulating water level control of a conical vessel. The neural network used in this study is composed of only four units-three for the input layer and one for the output layer.
    The effect of continuation of learning, the capability to follow the change of system characteristics, the effect of noise or misjudgment of time lag are discussed.
    The results found and the fact that this controller has no specific parameters to be tuned in advance showed that it is very adaptive and sufficiently strong against noise.
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  • Culture of Red Beet Hairy Root in Bioreactor and Recovery of Pigment Released from the Cells by Repeated Treatment of Oxygen Starvation
    Masahiro Kino-oka, Yasuhiro Hongo, Masahito Taya, Setsuji Tone
    1992 Volume 25 Issue 5 Pages 490-495
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.490
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    In the culture of red beet hairy root, the red pigment (mainly betanin) was released from the cells into medium when the cells were subjected to the culture condition under O2 starvation by keeping the concentration of dissolved oxygen in medium at 0 ppm. The amount of released pigment increased with increasing time length of O2 starvation during 26 h. However, an O2 starvation time of less than 16 h was employed to shorten the lag time for cell growth resumption after this starvation treatment. An adsorption column with a hydrophobic resin, Sepabeads SP 207 (styrene-divinylbenzene copolymer), was incorporated in a bioreactor system and the long-term culture of hairy root was carried out with repeated operations of cell growth, pigment release and recovery. In the culture with an O2 starvation time of 16 h, an extracellular production rate of pigment of 11.3 × 10–5 kg/(m3-broth·h) was obtained on the average.
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  • Continuous Drying of a Fine Particles-Water Slurry in a Powder-Particle Fluidized Bed
    Nobuyoshi Nakagawa, Kazumichi Ohsawa, Takayuki Takarada, Kunio Kato
    1992 Volume 25 Issue 5 Pages 495-501
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.495
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    The powder-particle fluidized bed is a new type of fluidized bed developed to fluidize fine particles to prevent their agglomeration in the bed.
    Continuous drying of a slurry of fine particles with water was carried out in a powder-particle fluidized bed, and its drying characteristics were examined. Moisture in the slurry evaporated almost fully in the bed, and the moisture content of the exiting fine particles was nearly zero under the range of operating conditions in this study. Temperature and relative humidity of the outlet gas agreed with those calculated by mass and heat balances across the bed without knowledge of the rates of heat and mass transfer.
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  • Dispersion of Coagulated Particles by Contractile Flow to Orifice
    Ko Higashitani, Nobuhisa Tanise, Atsuro Yoshiba, Akihiko Kondo, Hirosh ...
    1992 Volume 25 Issue 5 Pages 502-507
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.502
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    The breakup of floes composed of a small number of constituent particles by orifice contractile flow is investigated extensively by measuring the size of broken floes of PSL particles on a Coulter counter. It is found that (1) floes of maximum strength are obtained when they are formed in an electrolyte concentration greater than the critical coagulation concentration, and the strength is independent of the valency of electrolyte; (2) the average size of broken floes and the maximum number of constituent particles in a broken floe are successfully expressed as a function of the energy dissipation at the orifice; and (3) the mechanism of floe breakup in the contractile flow is different from that by ultrasonication (flocs are split into smaller agglomerates in the former case, but particles are ripped off one by one from the surface of flocs in the latter case).
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  • Synthesis and Properties of Powdered Oxide Superconductor by the Mist Pyrolysis Method
    Masanobu Awano, Yasumasa Takao, Keiko Kani, Hiroyoshi Takagi
    1992 Volume 25 Issue 5 Pages 508-514
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.508
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    Y-Ba-Cu-O and Bi-Pb-Sr-Ca-Cu-O superconductor powders were synthesized by the mist pyrolysis method. The crystalline phase and morphology of mist-pyrolyzed powders depended on the heating temperature, heating time, and concentration of starting solutions. Superconducting phase of Y-Ba-Cu-O and Bi-Pb-Sr-Ca-Cu-O superconductor (low-Tc phase) were obtained directly by this method. Sintered body of Y-Ba-Cu-O superconductor obtained by using mist-pyrolyzed powder had a density of above 95% of the theoretical density. The critical temperature (Tc) of Y-Ba-Cu-O superconductor (Tc end point) was 90 K and its critical current density (Jc) was above 230 A/cm2 (at 77 K). The Tc value of sintered Bi-Pb-Sr-Ca-Cu-O body was increased from 55 K to 103 K, because the low-Tc phase was converted to high-Tc phase by the long heat treatment. The optimum Jc value of Bi-Pb-Sr-Ca-Cu-O sintered body was 172 A/cm2 (at 77 K).
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  • Experimental Study of Flow Mechanics in a Hollow-Fiber Membrane Module for Plasma Separation
    Shiro Yoshikawa, Kohei Ogawa, Shinichi Minegishi, Tamiyuki Eguchi, Yas ...
    1992 Volume 25 Issue 5 Pages 515-521
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.515
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    Flow characteristics that control the performance of a hollow-fiber membrane module are investigated experimentally. The test fluid used is pure water, and the velocity at the entrance and at the exit of the bundle of fibers, the pressure loss and the transmembrane pressure are measured. It becomes clear that Hagen-Poiseuille’s law is almost applicable to the flow in respective fibers and that Darcy’s law is applicable to permeation through the membrane. In addition, impulse response tests are carried out and some information concerning dead space in the shell side and stagnation of liquid in an entrance cap is obtained. On the basis of the results, a simple model concerning the flow mechanism in the module is proposed and is confirmed to be appropriate.
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  • Reduction of Power Consumption for Pneumatic Conveying of Wet Granular Materials
    Fumiaki Takeuchi, Takeshi Kano, Toshiaki Yamada, Teruo Takahashi
    1992 Volume 25 Issue 5 Pages 522-526
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.522
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    Pneumatic conveyance of wet granular material was investigated, focusing on the reduction of power consumption. Flow patterns at various water contents were modelled and the physical properties of particles as well as the conveyance pressure drop were measured for polystyrene pellet conveying. Effects of vibration conditions on the pressure drop and conveyance efficiency were investigated. Favorable water content and vibration conditions were found to reduce the power consumption. It was confirmed that liquefaction resulted from a multiplier effect of water addition and vibration and contributed considerably to reduction of power consumption and prevention of choking. The applicability of these results was confirmed with actual devices.
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  • An Efficient Decomposition Algorithm for a Weighed Process
    Delin Qu, Dengwen Sun, Masaaki Muraki, Toyohiko Hayakawa
    1992 Volume 25 Issue 5 Pages 527-532
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.527
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    Considering the computation load of process simulation, it is necessary to assign a weight to each stream of a chemical process. Therefore, tearing criteria for the weighed process are proposed, which minimize the number of cut streams (cycle intervals) first and then search for an alternative stream with the minimum weight for each detected cycle interval. Based on them, an efficient decomposition algorithm is then developed, with two parts. One is to detect the cycle interval, using the weighed reachable vector method. The other is to determine the cut stream for each cycle interval through three indispensable procedures (searching, judging and regulating). After searching out an alternative stream with minimum weight, judging is carried out by verifying whether the detected cycle interval is broken or not. Then regulating is implemented by modifying the local weighed adjacency matrix. These three procedures are repeated until the stream with minimum weight is got. Finally, the optimal cut-set is obtained.
    Four test problems are examined. The proposed algorithm finds the minimum weighing sum for all these problems under the minimum number of cut streams.
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  • Model for the Separation of Glucose and Fructose at High Concentration Using a Semicontinuous Chromatographic Refiner
    Kwang Nam Lee, Won Kook Lee
    1992 Volume 25 Issue 5 Pages 533-538
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.533
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    The separation of aqueous mixtures of glucose and fructose at high concentration up to 500 g/l has been investigated by using a semicontinuous chromatographic refiner (SCCR) with the calcium form DOWEX 50W-X12 ion exchange resin as adsorbent and water as the isocratic eluent. At high concentration the equilibrium isotherms could be approximately represented in terms of a quadratic expression which allowed for nonlinearity and coupling between the glucose and fructose equilibria. A plug flow model with mass transfer effect was presented for calculating both products and on-concentrations in the SCCR unit. Factors such as feed concentration, purge rate and total number of columns were explored and the validity of the model was experimentally confirmed.
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  • Vortex Cavity Shape and the Associated Path-Line of Discharged Bubbles in an Aerated Vessel Agitated by a Rushton Turbine
    Koji Takahashi, Alvin W. Nienow
    1992 Volume 25 Issue 5 Pages 539-543
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.539
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    The vortex cavity behaviour and the path-line of bubbles just dispersed from the cavity at very low gassing rates have been determined by a photographic method. The cavity shows a strong instability. The cavity size increases with increase in gassing rates, with decrease in molecular weight and by the saturation of CO2 in water, but is independent of impeller speed. The position of path-lines of bubbles is almost the same as that of the vortex axis for a single-phase flow in spite of the different experimental conditions.
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  • Solubilities of Carbon Dioxide in Carboxylic Acids under High Pressures
    Jun-Shun Yau, Yung-Yi Chiang, Der-Shin Shy, Fuan-Nan Tsai
    1992 Volume 25 Issue 5 Pages 544-548
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.544
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    The solubilities of carbon dioxide in lauric acid, palmitic acid and arachidic acid have been measured in a semiflow apparatus over the temperature range from 373.2 K to 473.2 K at pressures up to 5.07 MPa. A correlation is developed to describe the experimental data and to calculate the solubilities of carbon dioxide in these three heavy carboxylic acids. Henry’s constants and the partial molar volumes at infinite dilution of carbon dioxide are determined from the measured solubility data.
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  • Operating a Foam Fractionating Column in Simple Mode
    R. Konduru
    1992 Volume 25 Issue 5 Pages 548-554
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.548
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    This paper discusses the correct way of operating a foam fractionating column strictly in simple mode. The system chosen was zinc and sodium lauryl sulphate. It was experimentally noticed that if the surface excess was measured at random operating conditions the column was producing inconsistent data, violating the conditions of simple mode operation. After thorough examination it was determined that the height of foam-liquid interface, air flow rate and bubble diameter must be mutually adjusted in order to bring the column close to its simple-mode operation. The results were compared with those of previous investigators, who used the similar apparatus, and it was concluded that the experimental method illustrated in this paper furnished more reliable data of simple-mode operation.
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  • Absorptive Studies of Aqueous Zinc Ions by Foam Fractionation in Simple Mode
    R. Konduru
    1992 Volume 25 Issue 5 Pages 555-560
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.555
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    This paper discusses the application of a foam fractionating column operating strictly in simple mode. The system chosen was zinc and sodium lauryl sulphate. Using the correct way of operating a foam fractionating column in simple mode, as was discussed in a separate paper by the same author, the combined influence of collector and metal ion concentrations on zinc surface excess was studied. Even a small amount of collector was found to be sufficient to saturate the bubble surface. However, for higher bulk zinc concentrations a higher collector concentration was required to maximize the zinc surface excess. The bulk zinc concentration and solution pH mutually affected the zinc surface excess. White a bulk zinc concentration of 0.15 mol/m3 was found to be optimum to maximize the zinc surface excess, a pH of 4.0 provided optimum surface excess for any bulk zinc concentration.
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  • Method of Estimating Surface Excess of Metal Ion in Foam Separation
    Keiichi Kato, Takuo Ishikawa, Yoichi Kasahara, Shinji Miyaki
    1992 Volume 25 Issue 5 Pages 561-569
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.561
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    Foam separation experiments were carried out in various SDBS (sodium dodecylbenzene sulphonate) solutions containing several kinds of metal perchlorates. General estimation of the dynamic surface excess of various kinds of metal ions were tried by use of a model (G.C. model) derived on the basis of the Gouy-Chapman theory of the diffuse double layer. In the model the effect of hydration of the metal ions was taken into account. The surface excess of metal ion (Γmetal) from bulk concentration composition was directly estimated by use of the surface excess of DBS– (dodecylbenzene sulphonate) (ΓDBS–), which was estimated using both the Davies adsorption theory and the G.C. model. The calculated values of Γmetal were in good agreement with the experimental ones far below the critical micefle concentration. Therefore, the enrichment and removal percentage in the foam separation technique can be predicted.
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  • Properties of Amylase Immobilized on a New Reversibly Soluble-Insoluble Polymer and Its Application to Repeated Hydrolysis of Soluble Starch
    Kazuhiro Hoshino, Masayuki Taniguchi, Masafumi Katagiri, Michihiro Fuj ...
    1992 Volume 25 Issue 5 Pages 569-574
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.569
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    A copolymer of glycidyl methacrylate (GMA) and N-isopropyl acrylamide (NIPAM) forms a reversibly soluble-insoluble (S-IS) polymer (GMA-NIPAM), whose solubility changes with the temperature of the solution. An amylase (Dabiase) was immobilized on GMA-NIPAN under alkaline conditions. The specific activity of Dabiase immobilized on GMA-NIPAM (D-GN) for saccharification of soluble starch was 90% that of native Dabiase and higher than that of conventional solid immobilized enzymes. D-GN was soluble below 32°C but insoluble above 44°C. When NaCl was added to a buffer solution (pH 5.0) with D-GN, the solubility response of D-GN to change in temperature was more sensitive than that in the buffer solution without NaCl. In addition, the temperature causing half of the maximum turbidity decreased by about 2.3°C whenever the NaCl concentration of the buffer solution was increased by 1%. D-GN was used successively for repeated hydrolysis reaction of soluble starch, in which D-GN was insolubilized not only by elevating the temperature of reaction mixture with 1% NaCl from 30°C to 38°C, but also by adjusting the NaCl concentration of reaction mixture to 4% at 30°C, followed by its batchwise recovery from a reaction product by centrifugation.
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  • Prediction of the Flux for the Reverse Osmosis of a Solution Containing Sucrose and Glucose
    Hiroshi Nabetani, Mitsutoshi Nakajima, Atsuo Watanabe, Shin-ichi Nakao ...
    1992 Volume 25 Issue 5 Pages 575-580
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.575
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    To predict the permeate flux value during reverse osmosis of a highly concentrated multi-solute solution such as fruit juice, applicability of the osmotic pressure model, which takes into account the effect of the concentration polarization phenomenon on the permeate flux value, to a binary solute solution containing sucrose and glucose was evaluated.
    To adapt the model to the highly concentrated binary solute solution, methods to estimate the dependence of density, viscosity, osmotic pressure, and solute diffusivity on the solute concentration were investigated.
    Defining the solution properties, the experimental permeate flux values agreed well with values calculated by the osmotic pressure model. The model, which had been applied only for dilute solutions containing one component, was therefore able to predict precisely the permeate flux for the highly concentrated binary solute solution without using any fitting parameters.
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  • Separation of Alcohol Aqueous Solutions by Reverse Osmosis and Pervaporation Using a Poly(1-Trimethylsilyl-1-Propyne) Membrane
    Shinobu Tanimura, Keiji Yamaguchi, Shin-ichi Nakao, Shoji Kimura
    1992 Volume 25 Issue 5 Pages 580-585
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.580
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    Ethanol and 1-propanol aqueous solutions were separated by reverse osmosis (RO) and pervaporation (PV) using a poly(1-trimethylsilyi-1-propyne) (PTMSP) membrane, and the membrane showed alcohol selectivity in both RO and PV. Flux decreased with time but selectivity did not change in PV. On the other hand, both flux and selectivity were constant with time in RO. Spiegler-Kedem’s equations predicted that the alcohol selectivity in RO significantly increased with increase in operating pressure.
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  • Separation of Nonaromatic C6 Compounds from Naphtha Cracking Raffinate by Adductive Crystallization
    Choul-Ho Lee, Kwang-Joo Kim, Seung-Kon Ryu
    1992 Volume 25 Issue 5 Pages 585-591
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.585
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    The separation of the nonaromatic raffinate found in naphtha crackers was studied using adductive crystallization with thiourea. Experimental results of the separation of cyclohexane from nonaromatic raffinate and on the separation capacity of three binary mixtures—methyl cyclopentane (MCP)-cyclobexane, MCP-n-hexane and cyclohexane-n-hexane—are presented in this study. Structure, habit and shape of adduct crystals were investigated to examine the adduction mechanism by SEM and X-ray diffraction. Separation factors as high as 92 and extent of separation up to 0.78 were observed for one adduction stage, and the separation by one stage is approximately 5.6 to 19.2 times greater than the maximum separation that could be obtained by one theoretical distillation stage. The tendency for adduction in thiourea was found to be cyclohexane > MCP >> n-hexane. Cyclohexane of a purity of 99.9 wt.% was obtained by 4-stage adductions from nonaromatic raffinate.
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  • Fluidization Characteristics of a Circulating Fluidized Bed with an Internal Nozzle
    Manabu Hattori, Hitoki Matsuda, Wojciech Nowak, Masanobu Hasatani
    1992 Volume 25 Issue 5 Pages 592-597
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.592
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    A recently developed method of gas combustion with circulating fluidized bed (CFB) is presented and discussed. The main area of study was the hydrodynamics of CFB equipped with an internal nozzle in the center of the riser. The paper describes the results of an experimental study of particle behavior in the system. Glass beads of 100 μm and FCC particles of 56 μm in diameter were employed as bed materials. It was possible to control particle hold-up by changing the ratio of the gas flow in the nozzle to the total gas flow (Qi/Q). Both the particle feed rate and the inflection point were varied with Qi/Q. In addition, the height of the inflection point was dependent on the nozzle height.
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  • Effects of Gel Composition on Separation Properties of Ethanol/Water Mixtures by Acrylamide Gel Membranes
    Shuji Sakohara, Yoshihiro Maekawa, Yasushi Tateishi, Masashi Asaeda
    1992 Volume 25 Issue 5 Pages 598-603
    Published: 1992
    Released on J-STAGE: April 05, 2005
    DOIhttps://doi.org/10.1252/jcej.25.598
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    Separation performance of acrylamide gel membranes for ethanol/water mixtures is greatly affected by the effective size of the pores in the network and the network’s homogeneity. With increasing concentration of crosslinker (N,N′-methylenebisacrylamide), coarse and dense parts of a networks, i.e., the heterogeneous structure, are produced in the gels, though the effective size of the pores in the network must be reduced. Such a heterogeneous structure appears remarkably at low concentration of primary monomer (acrylamide). The coarse part of the network significantly affects the leakage of ethanol molecules through a membrane and the state of water in the gels, which is closely related to the selective permeation of water through the membrane. As a result, optimum gel compositions exist for the permeation of water and for the obstruction of ethanol permeation, respectively.
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