KAGAKU KOGAKU RONBUNSHU
Online ISSN : 1349-9203
Print ISSN : 0386-216X
ISSN-L : 0386-216X
Volume 15 , Issue 3
Showing 1-41 articles out of 41 articles from the selected issue
  • Yasuo Suzuki, Masanori Konno, Kunio Arai, Shozaburo Saito
    1989 Volume 15 Issue 3 Pages 439-445
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Supercritical carbon dioxide (SC-CO2) fractionation of fatty acid ethyl esters (FA) derived from fish oil is carried out, using a packed column of 20mm internal diameter and 2.5m total packed height. While the SC-CO2 phase saturated by a FA mixture flows upward through the column, solutes rich in the heavier components condense because of the longitudinal temperature increase of the column and trickle down countercurrently to the SC-CO2 phase. This rectification effect promotes the separation efficiency greatly and results in eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) purity of over 90wt% with about 40% yield, although the purity depends on the content of other components which have the same carbon number as EPA or DHA. Fractionation curves obtained in this work, however, indicate the possibility of the separation of such components only by SC-CO2 fractionation.
    Download PDF (1165K)
  • Masayoshi Kubota, Harumi Matsuzaki, Sankichi Takahashi, Setsuo Inoue
    1989 Volume 15 Issue 3 Pages 446-450
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The effects of supercritical CO2 density, resin volume and injected sample volume on separations of eicosapentanic acid, obtained from fatty acid methyl esters of fish oil, were studied by use of supercritical CO2 chromatography on an industrial scale. Almost all liquid in resins was extracted, using supercritical CO2. The CO2 volume for separation of eicosapentanic acid depended on supercritical CO2 density and packing resin volume. Product parity depended on supercritical CO2 density and the injected sample volume. Using the supercritical CO2 chromatography method, eicosapentanic acid with a concentration of 90% and a yield of 60% was obtained.
    Download PDF (797K)
  • Yorishige Matsuba, Teruo Takahashi, Yoshiro Kitamura
    1989 Volume 15 Issue 3 Pages 451-457
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    A solvent extraction process using a 5m-long microporous tube was developed for separation of fatty acids. Experiments were carried out for two systems : acetic acid-water -MIBK and long-chain fatty acids -acetonitrile (containing 10 wt% water) -n-heptane. In the former system the membrane mass transfer coefficient was estimated to be 7.58×10-7m/s. Using this process, long-chain fatty acids such as oleic and linoleic acid, which cannot be separated by conventional distillation, were successfully separated by degree of unsaturation. This process was also applicable to the fractional separation of highly unsaturated fatty acids such as the EPA and DHA found in fish oils.
    Download PDF (1139K)
  • Yoshihiro Etoh, Norio Ohashi, Chuichi Goto
    1989 Volume 15 Issue 3 Pages 458-463
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Simultaneous solvent extraction-stripping was carried out with a membrane-integrated extractor. Crystalline CuSO4·5H2O was recovered from Cu-containing water by the extractor combined with a fluidized-bed crystallizer. Extraction tests were carried out, using SME-529 (a solvent from Shell Chem. Co.) with two apparatuses of different scale containing tubular fluoropolymer membranes (inner dia. 2 mm, pore dia. 0.1 μm); the inner surface area for the smaller one with 21 membrane tubes was 6.59 × 10-2m2, and that for the larger one with 528 tubes was 2.32 m2.
    Then we proposed a diffusion model by which Cu concentrations in a set of a feed solution, solvent and stripping solution can be calculated from the extraction equilibrium and the mass transfer coefficients available through simple experiments. The calculated values agreed well with the experimental values. A design method for a commercial-scale plant is proposed, based on the diffusion model.
    Download PDF (860K)
  • Yuji Takenaga, Masahiro Nawata, Nobuyuki Sakata, Masaru Senuma, Tetsuy ...
    1989 Volume 15 Issue 3 Pages 464-469
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Pyrogen removal using a fixed bed of immobilized histidine was investigated. An aqueous solution containing endotoxin (20 ng/cm3) was used for this study.
    The breakthrough curve of pyrogen was not clear, but a practical breakpoint was obtained. The concentration of pyrogen in effluent and the adsorption capacity depended on ionic strength. When the ionic strength was less than 0.11 mol/dm3 and the flow rate was 0.021 cm/s, the concentration of pyrogen in the effluent was less than 0.1 ng/cm3.
    In addition, when the bed was compressed the concentration of pyrogen in the effluent decreased and the adsorption capacity increased, but the pressure drop also increased. From these results, the favorable compression ratio was found to be about 0.1.
    Download PDF (867K)
  • Makoto Arai, Hideki Fukuda, Yasuhiro Nojima, Tsutomu Okuyama, Nobutaka ...
    1989 Volume 15 Issue 3 Pages 470-474
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The adsorption performance of dextransulfate-cellulose gel for low-density lipoproteins (LDL) in human plasma was investigated. Considering the mathematical model for the mass transfer of LDL, it was found that mass transfer was limited by pore diffusion within the gel. Maximum adsorption efficiency was obtained by the gel with an effective internal volume fraction in the range from 0.65 to 0.7.
    Download PDF (641K)
  • Kanji Miyabe, Tetsuya Kawazoe, Masato Yamaguchi, Kouji Kitazawa
    1989 Volume 15 Issue 3 Pages 475-480
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    An industrial-scale reversed-phase liquid chromatograph was developed by using a multicolumn system. Its use reduced the volume of solvent and the operation time for chromatography, to about one -tenth of those required in a conventional elution. As a result, the maximum concentration of the objective component increased approximately fifteen times.
    A simulation method was used to optimize the operational conditions of the column system. The validity of the calculated result was confirmed experimentally.
    In industrial-scale liquid chromatography the multicolumn system effectively increases the efficiency of the whole purification process.
    Download PDF (947K)
  • Masaki Minemoto, Naoyuki Kamishima, Shigekazu Hatano, Toru Etoh, Takes ...
    1989 Volume 15 Issue 3 Pages 481-488
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Within the closed system of a manned space station or similar environment, it is necessary to establish a life support system that removes CO2 produced by metabolism and produces O2. As a step in that direction, we studied a removal and concentration system of CO2 employing solid amine for adsorption and steam for desorption. We have performed basic tests on adsorption equilibria and adsorption breakthrough measurements, and have conducted continuous operational adsorption/desorption tests with a model apparatus.
    The results indicated that the adsorption equilibria of CO2 and water that were adsorbed simultaneously did not affect each other. CO2 showed a Freundlich type adsorption isotherm, water a Henry type.
    In addition, we obtained the dependency of these adsorption equilibria on temperature, relative humidity and CO2 concentration. We also an obtained overall mass transfer coefficient for CO2 adsorption. We then examined two solid amine packed columns (240mm internal diameter and 200mm height) to alternately perform CO2 adsorption and desorption, and confirmed that they were sufficient to remove and concentrate the amount of CO2 produced by two persons (2kg·d-1).
    Download PDF (1057K)
  • Yoshio Nakano, Yasunori Tsuneshige, Hideki Shimizu, Takeshi Katou
    1989 Volume 15 Issue 3 Pages 489-496
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The micropores of molecular sieving carbon (MSC) were controlled by heattreating a precursor of MSC impregnated with mixtures of hydrocarbon in a stream of nitrogen. Coconut char having micropores less than 0.5nm in diameter was used as the precursor and heat treatment was carried out at a temperature of 1023K to 1223K after heating MSC at a rate of 10K/min. Hydrocarbon mixtures used in this study were diphenyl·naphthalene, coal-tar·naphthalene and fluorene·naphthalene. The performance of the treated MSC for separation of oxygen and nitrogen was evaluated from the standpoints of treatment conditions, adsorption properties and micropore size distributions.
    Adsorption rates of oxygen and nitrogen on the treated MSC were adjustable by combination of hydrocarbons, their concentrations and heat treatment. It was found that the treated MSC has micropores of 0.280.4nm diameter and exhibits high ability for separation of oxygen and nitrogen. The mass transfer resistance at the micropore mouth was much larger than that inside the micropore in the treated MSC.
    Download PDF (1197K)
  • Ryoichi Kuboi, Wei-Hong Wang, Katsuji Morimatsu, Setsuji Tone, Isao Ko ...
    1989 Volume 15 Issue 3 Pages 497-503
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Aqueous two-phase extraction was applied to the separation of papain from papaya latex, employing two systems : PEG (polyethylene glycol) / Dex (dextran) and PEG/PK (potassium phosphate). Partition coefficients of papain depend on electrostatic, steric and hydrophobic interaction between papain and the phase system. The PEG/PK system gives higher partition coefficient and separation factor than the PEG/Dex system because of relatively strong hydrophobic interaction between PEG and papain molecules. A direct purification process in which papaya latex powder was fed directly to the aqueous two-phase system was successfully operated and no deteriorate was observed in contrast to the extraction process using leachate liquor of the latex.
    A modified PEG was also employed, in which the OH group was substituted by several ligands having specific affinity to papain. An improvement of partition coefficient and separation factor was observed, especially in the case of PEG modified with Procion Blue and potassium phosphate.
    Download PDF (1092K)
  • Eiichi Kunugita, Jong Hwa Kim, Isao Komasawa
    1989 Volume 15 Issue 3 Pages 504-510
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The extraction of lithium and sodium with commercial β-diketones such as LIX54 (α-acetyl-m-dodecylacetophenone) and LIX51 (α-perfluoroalkanoyl-m-dodecylacetophenone) was studied, together with the synergic effect brought about by a neutral ligand, TOPO (tri-n-octylphosphine oxide).
    Only LIX51 can extract lithium in a single-extractant system. The extracted species is a mixture of LiR (RH) and LiR2 (RH), and its mean composition is LiR (RH) 1.3 where RH and R denote the extractant and its anion, respectively.
    The combination of LIX54 (or LIX51) and TOPO extract lithium, the mean composition of extracted species being LiR (TOPO) 1.3. The extraction peformance of the combination of LIX51 and TOPO is 4.65 × 104 times that of LIX 51 alone or LIX54 plus TOPO.
    Sodium is extracted only by the combination of LIX51 and TOPO, the mean composition of its extracted species being NaR (TOPO) 1.3. The extractability of sodium is much less than that of lithium, suggesting good propects for the separation of the two elements.
    Download PDF (988K)
  • Yutaka Ikushima, Kiyotaka Hatakeda, Norio Saito, Shota Ito, Tomio Goto
    1989 Volume 15 Issue 3 Pages 511-518
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    A supercritical carbon dioxide extraction was carried out to separate and concentrate docosahexaenoic acid (DHA) in high purity from the entrails of squid using a gas flow method. Selective extraction of DHA from the squid oil could be effectively promoted without posttreatment by employing a separation chamber packed with AgNO3 supported on silica gel and by raising the operating pressure at an appropriate degree of extraction. A large portion of DHA contained in the oil could be extracted and concentrated between 70 and 90 % degree of extraction, and the concentration reached over 90 wt.%.
    Furthermore, the addition of hexane, ethyl acetate, and acetone to the carbon dioxide as entrainers was found to enhance the extraction efficiency of the squid oil. A parameter including the solubility parameter made it possible to estimate the influence of the entrainer on supercritical carbon dioxide extraction of lipids from natural products such as the entrails of squid.
    Download PDF (1158K)
  • Satoshi Furuta, Noboru Ikawa, Ryuichi Fukuzato, Nobuyuki Imanishi
    1989 Volume 15 Issue 3 Pages 519-525
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The vapor-liquid equilibrium data for the carbon dioxide-ethanol-water ternary system, which are important to the study of the optimum condition of ethanol extraction from dilute aqueous solutions using supercritical carbon dioxide, were obtained. The experimental conditions of temperature and pressure were 303.2K through 363.2K and 5.6MPa through 13.2MPa, respectively.
    When the temperature was increased, ethanol concentration in the fluid phase increased to more than 89mol%, which is the maximum azeotropic concentration for atmospheric distillation. The optimum extraction condition in the extraction column was examined, on the basis of vapor-liquid equilibrium data, to be a temperature in the range of 303.2K through 333.2K and a pressure of 10MPa, with the ideal temperature increasing as the ethanol concentration in the liquid phase increases.
    Download PDF (1020K)
  • Atushi Shono, Iwao Akiba, Nobuyuki Imaishi, Katsuhiko Fujinawa, Mitsun ...
    1989 Volume 15 Issue 3 Pages 526-532
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Applicability of liquid membranes to the solvent extraction of Ga and In from leaching solution of gypsum, which is a residue of zinc recovery from black ore, was studied experimentally. The leaching sulfuric acid solution contains about 300 ppm of Ga and In together with 16, 000 ppm of Al and 30, 000 ppm of Zn. As the extractant, Versatic-10 (V10) which is used in the conventional process, and 2-bromodecanoic acid (2BDA) were tested. It was found experimentally that 2BDA is more effective than V10 as an extractant, and that application of the supported liquid membrane is difficult because of low permeation rate. The application of the liquid surfactant membrane was found to be promising by use of 8 vol% Span 80 as the surfactant and 20 vol% 2BDA as the extractant. The required amount of the extractant and the volume of the extraction apparatus can be reduced respectively to 1/50 and 1/10 to those in the conventional process.
    Download PDF (962K)
  • Michiaki Matsumoto, Masahiro Goto, Kazuo Kondo, Fumiyuki Nakashio
    1989 Volume 15 Issue 3 Pages 533-539
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Separation of copper from a sulfuric acid leaching solution of manganese nodules was carried out by using a liquid surfactant membrane containing LIX 65N as a mobile carrier and glutamic acid di-oleylester ribitol as a surfactant.
    The permeation rate of copper ion is explained by taking account of the interfacial reaction between LIX 65N and copper ion and the mass transfer of copper ion in external aqueous solution along with the permeation of water from external to internal aqueous solutions.
    It is found that the separation factor of copper ion against ferric ion and the permeation rate of copper ion in sulfate media are enhanced by a liquid surfactant membrane containing sodium dioleyl sulfosuccinate as an additive in addition to the above system.
    Download PDF (972K)
  • Ryuichi Ueoka, Yoko Matsumoto, Masanori Cho, Tatsuyu Ikeda, Toshihiro ...
    1989 Volume 15 Issue 3 Pages 540-545
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The enantioselective hydrolysis of a long-chain substrate (p-nitrophenyl N-dodecanoyl-D (L) -phenylalaninate, D (L) -S12) was carried out in hybrid assemblies (liquidsurfactant membrane) composed of 59 mol % vesicular (ditetradecyldimethylammonium bromide, 2C14Br) and 41 mol% micellar (hexadecyltrimethylammonium bromide, CTAB) surfactants.
    High enantioselectivity (kLψ/kDψ=35) was obtained for the hydrolysis of D (L) -S12 with the active tripeptide (N- (benzyloxycarbonyl) -L-phenylalanyl-L-histidyl-L-leucine, Z-PheHisLeu) at the phase transition temperature (15°C) of the hybrid assemblies of 2C14Br and CTAB, which was kept stable as spherical large vesicles with a radius of 110-115 nm for at least one week.
    Download PDF (1157K)
  • Taku Matsushita, Katsuya Ogawa, Norikazu Koga, Kazumori Funatsu
    1989 Volume 15 Issue 3 Pages 546-551
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    A method for purification of carotenoid pigments from cultured carrot cells was established. First, carotenoids were extracted with acetone from cultured carrot cells, and then β-carotene was purified from the carotenoids by adsorption chromatography using activated alumina.
    The relation between cell growth and carotenoid production of carrot cells in shake culture and air-lift culture was studied by using the purification method described above. The results indicated that carotenoids were growth-dependently produced from the early logarithmic phase of cell growth, and that productivity decreased in the stationary phase, even if medium was exchanged in the stationary phase.
    Finally, 29.4 μg/l-medium of β-carotene was obtained from high-density cultured carrot cells using an air-lift column of 1 liter volume equipped with a draft tube.
    Download PDF (956K)
  • Hisao Takase, Yoshihide Yoshimura
    1989 Volume 15 Issue 3 Pages 552-558
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    An analysis and experiments were made on the separation and concentration of uranium from the slurry adsorbent used for recovery of uranium from seawater in a system where adsorption and desorption occur simultaneously. Concentration of the adsorbate was carried out by direct contact of ion exchange resin with the eluting solution containing the adsorbent. By the use of different equilibrium relations for the slurry and the ion exchange resin, the adsorbate was concentrated in the ion exchange resin, and the amount used of the eluting agent could be reduced.
    Meterial balance equations for an agitated vessel were derived for a linear equilibrium system. The calculated results were in fairly good agreement with the experimental values assuming the mass transfer coefficient for the ion exchange resin to be 0.286 times that in an aqueous solution. This may be attributed to an influence induced by the presence of titanium oxide slurry adsorbent.
    Download PDF (1119K)
  • Kunihiko Takeda, Itaru Ichihara, Toshinori Watanabe, Heiichiro Obanawa
    1989 Volume 15 Issue 3 Pages 559-566
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    In an ultra multistage separation using adsorption-desorption reactions, it takes much time to obtain high separation and the concentration of the separated material tends to be extremely low. The concentration is mainly dominated by the boundary conditions of an adsorption band, and this paper shows that “displacement” conditions are preferable for industrial purposes. On the other hand, the analysis of a separation unit is important in order to reduce the time required for the separation. Experimental studies of separations concerning uranium isotopes and rare earth elements show that a theoretical analysis of the separation unit using fixed coordinate axes is useful in reducing the time, and can be made by elucidating the transition state of the separations.
    Download PDF (1097K)
  • Kunihiko Takeda, Itaru Ichihara, Toshinori Watanabe, Heiichiro Obanawa
    1989 Volume 15 Issue 3 Pages 567-573
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Chemical reactions play an important role in an ultra multistage separationusing an adsorption-desorption system. The reactions are favorable for forming displacement boundaries in a separation column as well as for enhancing separation efficiency in a separation unit. Several kinds of “addends”, which dominate the boundaries and the efficiency, are discussed in this report. The addition potential strengths (Δμi) of the addend were introduced, and the relation between the addition potential strengths and the formation of displacement boundaries was examined. As a result of semi-quantitative consideration, it was elucidated that more than two addends are indispensable for forming three displacement boundaries. The addends also act as separation addends, such as protons for separation of carbon or boron isotopes, electrons for uranium isotopes separation and organic compounds for separation of rare earth elements.
    Download PDF (984K)
  • Kunihiko Takeda, Itaru Ichihara, Fumiaki Kawakami, Keiji Kawano
    1989 Volume 15 Issue 3 Pages 574-580
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The separation energy in an adsorption-desorption process is known to be relatively large because the process can be classified as a partilly reversible one. In this report an ultra multistage separation process using an adsorbent for separation of uranium isotopes was studied and a separation system in which separation energy can be partially recovered was discovered.
    The reaction, called the “addox reaction”, was discovered by unifing all reactions in a separation system as addition reaction and introducing addition potential strengths and their distribution functions. Theoretical and experimental results were obtained, and more than 90% of the energy consumed could be recovered. These results also show that the separation energy of adsorption-desorption processes is substantially recoverable.
    Download PDF (1116K)
  • Yoshio Harano, Hiroshi Ooshima, Minoru Asahina, Taro Shimada, Hideo Ya ...
    1989 Volume 15 Issue 3 Pages 581-586
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The nucleation of thermolysin from its aqueous solution was studied at a constant rising rate of ionic strength b, 303K, pH 8.0 and an agitation rate of 600/min, using (NH4) 2SO4 as a precipitant. Nucleation was detected through the change of light transmittance of the solution. The data were analyzed theoretically by a dynamic technique for nucleation. As a result, semi-empirical relations, Eqs. (13) and (13'), were found to hold for the relationship between the width of maximum allowable super-ionic strength, i.e. the metastable zone width ΔΓm and b. Surface energy σ and radius rc, consisting number of molecules m and free energy chang in formation ΔGc of the critical nucleus, at Γm= 67 and S=2.7, were estimated to be 0.22 erg/cm2, 4.5 nm, 8.9 and ΔGc= 11.2 kJ/g-mol-nucei respectively. The salting-out coefficient of (NH4) 2 SO4 was 1.11.
    Download PDF (831K)
  • Kunio Nagahama, Daisuke Hoshino, Koji Maeda, Masayo Itoh
    1989 Volume 15 Issue 3 Pages 587-596
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    To investigate the solvent effect of liquefied gases on the solid-liquid equilibrium for the eutectic binaries, vapor-liquid-solid equilibrium data for the ternary systems were measured. Based on temperature-and pressure-dependence on elapsed time for cooling the mixture, the vapor-liquid-solid equilibrium point was determined experimentally.
    The benzene-cyclohexane system was chosen as an example of the eutectic binary system, and propane as well as chlorodifluoromethane (R 22) were employed as a solvent. Vapor-liquid-solid-equilibrium data for the propane-benzene-cyclohexane and the R22-benzene-cyclohexane ternary systems were obtained. The solid-liquid equilibrium data show that propane has the capability to move a eutectic composition to the cyclohexane-rich side while R22 can move it to the benzene-rich side. All experimental data were correlated well by use of the activity coefficient equation.
    Finally, a new continuous crystallization process is proposed, based on the solvent effect on a eutectic composition change. By simulating a process consisting of two crystallizers and a V-L separator, its feasibility was demonstrated.
    Download PDF (1519K)
  • Kazuhiro Kumeta, Seishu Yamamoto, Toshio Masuoka, Kensaku Mizoguchi
    1989 Volume 15 Issue 3 Pages 597-603
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The dependency of gas separation characteristics of Polyethersulphone hollow-fiber membranes on spinning conditions was investigated. The dope solution was composed of polyethersulphone and N-methyl-2-pyrrolidone. Water was used as coagulant agent.
    The draft ratio and temperature of the inside coagulant greatly influenced the oxygen-enriching ability of the hollow-fiber membranes. The ability rose with increasing draft ratio when low-temperature water was used as the inside coagulant. Such effects were explainable as being due to orientation of polymer molecules and to strong the coagulation at low temperature.
    Moreover, addition of lithium nitrate to the dope solution gave high separation ability at a certain draft ratio even at room temperature.
    Download PDF (985K)
  • Hidetoshi Kita, Shigeaki Sasaki, Kazuhiro Tanaka, Ken-ichi Okamoto, Ma ...
    1989 Volume 15 Issue 3 Pages 604-610
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Separation of water-ethanol mixtures through asymmetric polyimide membranes prepared by the phase inversion process was carried out by means of the pervaporation method. The permeation flux and separation factor of pervaporation through the asymmetric polyimide membranes for a water 10wt%-ethanol 90wt% mixture at 75°C were 1.29kg·m-2·h-1 and 57, respectively. The esterification of carboxylic acid with ethanol accompanied by pervaporation was investigated using the asymmetric polyimide membrane in order to shift the equilibrium and increase the conversion of the esterification by removal of water from the reaction mixture. It was observed that the removal of water by pervaporation shifts the equilibrium further in favor of the ester formation and a conversion greater than the equilibrium value without pervaporation can be obtained. The degree of conversion at different molar ratios of acid to ethanol was calculated, using the rate equation of the esterification accompanied by pervaporation, and the effect of membrane performance on conversion was discussed.
    Download PDF (1282K)
  • Minoru Iwata, Teruo Fujimoto
    1989 Volume 15 Issue 3 Pages 611-616
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    A tubular charge-mosaic membrane with polyethylene net backing was fabricated by the dipping method and tested for dialysis. The membrane material was a fourcomponent pentablock copolymer of the ISBAI type, poly (isoprene-b-styrene-b-butadiene-b- (4-vinylbenzyl) dimethylamine-b-isoprene), synthesized by a sequential living anionic polymerization and further modified chemically. The membrane showed high permeability only for sodium chloride in mixed aqueous solutions with non-electrolytes such as saccharose.
    Download PDF (753K)
  • Hirotsugu Kikuchi, Jun Hattori, Yuichiro Mori, Tisato Kajiyama
    1989 Volume 15 Issue 3 Pages 617-622
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    A polymer/ (liquid crystal) composite thin film containing chiral crown ether was prepared by a water casting method. In this film, liquid crystalline material formed a continuous phase in a fibrillar network of the matrix polymer. Therefore, the liquid crystalline phase could be a low-viscosity diffusion phase for carriers. The permeation characteristics for D-and L-isomers of amino acid salt through the composite thin film were investigated. The ternary composite thin film exhibited a high ability of optical resolution for D-and L-amino acid salts and a large flux due to thinning preparation of the ultrathin composite film. Furthermore, it is suggested that the chiral helical alignment in a nematic phase was induced by addition of CR molecules, also fairly enhancing the efficiency of optical resolution.
    Download PDF (1187K)
  • Katsushi Murakami, Takamichi Saeki, Yasunori Michiki, Atsuhito Itomine ...
    1989 Volume 15 Issue 3 Pages 623-629
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Decolorization of yeast-separated waste water from cultured broth at a baker's yeast manufactring plant was tested by using polymer membranes. NTR-7410 membrane among the membranes tested showed the best performance.
    The effects of operating conditions on the permeation flux and rejection were studied. Rejection of colored substance did not depend on operating pressure or circulation velocity. The flux rose with increasing circulation velocity and became almost constant at high velocity. The flux was in proportion to the operating pressure.
    Batch concentration of the waste water to volume reduction factor (VRF) 10 was carried out by using a NTR-7410 spiral-wound module under the following conditions : operationg pressure, 1.9 MPa ; circulation velocity, 0.2m·s-1; temperature, 30°C. The mean flux and rejection of colored substance were 6.9×10-6m3·m-2·s-1 and 98%, respectively.
    The membrane surfaces after batch concentration were observed by a scanning electron microscope. The membranes were cleaned by several detergents. It is concluded that the reduction of flux was not caused by degradation of the membrane itself, but mainly by plugging of the pores. The result of economic evaluation compared with the evaporation method indicate that decolorization of the waste water by NTR-7410 membrane may be at a used practically baker's yeast manufacturing plant if the membrane replacement cost is substantially reduced.
    Download PDF (1369K)
  • Toshiro Murase, Eiji Iritani, P. Chidphong, Katsuhiro Kano, Kunio Atsu ...
    1989 Volume 15 Issue 3 Pages 630-637
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    To attain high flow-rate microseparation of dilute suspension which contains very fine particles, thin-cake filtration is studied using a dynamic filter with a rotating cylinder of a ceramic membrane. A much higher filtration rate can be obtained by dynamic filtration than that encountered in static-cake filtration because the filter cake is continuously swept from the ceramic membrane by the high-speed rotation of the rotor. The dynamic filtration equation is derived by *introducing a rotatory filtration rate factor jr, defined as the ratio of static-cake resistance to thin-cake resistance, into conventional Ruth filtration equation. On the basis of the fact that the jr-value depends upon the rotor Reynolds number and the ratio of annular gap width to inner-cylinder radius provided other operational veriables are constant, a method is developed for evaluating the variations with time of filtrate volume using the filtration characteristics of the conventional cake filtration. It is also demonstrated that the dynamic effects become marked with increasing slurry concentration and decreasing applied filtration pressure, and that almost the same final equilibrium filtration rate can be obtained irrespective of the average pore size of the ceramic membrane.
    Download PDF (1203K)
  • Takuo Imasaka, Nobuhiko Kanekuni, Hiroyuki So, Shigeru Yoshino
    1989 Volume 15 Issue 3 Pages 638-644
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The feasibility of gas-liquid two-phase cross-flow filtration was studied, using five vertically connected membrane modules in which two hundred microporous ceramic tubular membranes were bundled. The following results were obtained : 1) There was no significant difference of permeate flux in each stage of the modules, even though flow conditions of gas-liquid mixture were slightly different. 2) Permeate flux in two-phase cross-flow filtration was dominated by a superficial linear velocity of two-phase mixture. 3) It was suggested that the gas-liquid two-phase cross-flow filtration system operated by the air-lift pump method was more advantageous in power saving than the conventional liquid single-phase cross-flow filtration system.
    Download PDF (1394K)
  • Tadao Nakashima, Masataka Shimizu
    1989 Volume 15 Issue 3 Pages 645-651
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Cross-flow microfiltration of stabilized oil-in-water emulsion was studied, using a novel porous glass tubular membrane of minutely controlled pore size in the range of submicron to micron. Filtration factors such as pressure, linear velocity and observed rejection of the emulsion and pore size of the membrane that influence oil permeation flux were experimentally studied. Three different types of flux curves on pressure were observed according to the relative relations of dispersion particle size, Dp and pore size, Dm : Dp> Dm, DpDm and Dp<Dm at a given velocity ofemulsion. These curves also depended on both the formation of gel layer on the membrane and the Reynolds number, Re.
    Particle fractionation by membrane was found in the low pressure range of 50kPa or so, but increasing pressure led to particles rearrangement and gel compaction with their partial deformation and a limiting flux was reached. No coalescence of oil drops was observed in any of the experiments.
    Download PDF (1368K)
  • Takeshi Takahashi, Hiroshi Kubo, Akira Kanagawa
    1989 Volume 15 Issue 3 Pages 652-657
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The effects of deposited particles on performance of the Nuclepore filter were studied theoretically and experimentally under conditions of the collection mechanisms of inertia and interception. A capillary filter model given by Pich was chosen as a model of the Nuclepore filter. The process of particle deposition was calculated by simulating the motion of particles using the Monte Carlo simulation method.
    The simulation results were used to estimate the collection efficiency and to find the morphology of deposited particles. A comparison between the simulation and experimental results was presented. The theoretically predicted collection efficiency was in agreement with experiments for the collection mechanism of inertia predominance.
    Download PDF (1473K)
  • Hiroshi Kimura, Susumu Hasegawa
    1989 Volume 15 Issue 3 Pages 658-662
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Supplementary filter cloth was placed in the middle in the filtering chamber of a conventional filter press to promote the filtration rate, which was then measured as the number of intermediate cloths was changed from one through four.
    The result are summarized as follows.
    1) When a single cloth was attached, the filtration rate was almost the same as in the conventional arrangement.
    2) By placing two cloths, the filtration rate was extremely enhanced.
    3) Increasing the number of cloths to more than two enhanced the filtration rate only a little compared with the case of placing two cloths.
    Download PDF (610K)
  • Hajime Tamon, Hitoshi Yano, Morio Okazaki
    1989 Volume 15 Issue 3 Pages 663-668
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    When electrons of low energy collide with gas molecules, negative ions are formed. This process is known as electron attachment. The negative ions can be separated from the neutral gas in the electric field. A new principle of separation of a very dilute component from a gas mixture, using electron attachment, was proposed. Two kinds of separation equipment whose electron sources were respectively a photocathode and a glow discharge were constructed and the separation performance of SF6 from N2 was measured in order to verify the proposed principle. In the photocathode equipment, the dependence of separation performance on the concentration of SF6, the pressure and the applied voltage were observed. Because of the low electron emission from the photocathode, high separation performance was not achieved. If sufficient electrons are supplied, the performance would be improved. In the glow discharge equipment, sufficient electrons were produced and much higher separation performance was obtained than that in the photocathode equipment. Both experimental results showed that this separation principle is especially effective in the case where the concentration of the gas to be separated is very dilute.
    Download PDF (981K)
  • Ryoichi Kuboi, Yoshiaki Mori, Isao Komasawa
    1989 Volume 15 Issue 3 Pages 669-673
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    A tailored reverse micelle solution was prepared by adding a fixed amount of pure or salt water to a mixture of isooctane and Aerosol OT. The water content and size of the resulting micelle could be controlled independently of the concentration of salt and AOT.
    The micelle size distributions were measured by the dynamic light scattering method. The solubilities of several powdered proteins of different size were measured and found to be related to the size of the protein and the water-pool containing the protein. Separation of α-Chymotrypsin, Cytochrome-c and BSA by the selective solubilization was successfully carried out, although BSA was denatured in the process.
    Download PDF (899K)
  • Koji Yamamoto, Mitsugu Nakae
    1989 Volume 15 Issue 3 Pages 673-675
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Supercritical carbon dioxide was used to remove methylene chloride from granular polycarbonate. Supercritical CO2 was continuously passed through a fixed bed of 400 mg of PC involving methylene chloride. It was confirmed that removal of the solvent was possible even below the glass transition temperature (Tg=155°C) of polycarbonate. In addition, Fick's model was employed to yield the diffusion coefficient of the removal process. Calculated concentration curves using the value of the diffusion coefficients agreed well with the experimental ones.
    Download PDF (421K)
  • Yoshio Iwai, Benjamin C.-Y. Lu, Hiroshi Yamamoto, Yasuhiko Arai
    1989 Volume 15 Issue 3 Pages 676-681
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The cubic equation of state having three constants, recently proposed by Yu et al., was applied to correlate the solubilities of solid components in supercritical fluids and the entrainer effect on solubilities. Three kinds of mixing rules for the constants (conventional mixing rules with one binary interaction parameter, those with two parameters, and local composition mixing rules) were adopted here and their applicabilities were examined. The solubilities and the entrainer effect can be successfully correlated by using the conventional mixing rules with two parameters and the local composition mixing rules with two parameters. However, it should be noted that the conventional mixing rules with two parameters give the best results for the system of which the solubility is very small near infinite dilution.
    Download PDF (897K)
  • Takuo Imasaka, Nobuhiko Kanekuni, Hiroyuki So, Shigeru Yoshino
    1989 Volume 15 Issue 3 Pages 681-683
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Gas-liquid-solid three-phase cross-flow filtration of yeast suspension was experimentally studied using a multi-channel ceramic membrane module. With appropriate solid-content ratio and feed gas flow rate, a higher permeate flux was obtained than with two-phase cross-flow filtration. However, it was noted that such operating conditions are likely to cause clogging of the flow channels of the membrane module by the solid particles. It was also difficult to separate the solid particles in the separator.
    Download PDF (589K)
  • Masao Sambuichi, Hideo Nakakura, Kunihisa Osasa, Katuaki Fujita
    1989 Volume 15 Issue 3 Pages 684-687
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The droplet separation and coalescence process of heavy oil/water emulsion was experimentally investigated with a glass beads bed under constant-rate filtration. A mathematical model for the separation process was proposed on the basis of deepbed filtration theory. The relationships between the experimental constants and the operating parameters were correlated by empirical formulae. The results could be readily used to predict the practical separation of hydrophobic droplets.
    Download PDF (630K)
  • Naohiro Shiragami, Toshio Kajiuchi, Yukihiko Hoso
    1989 Volume 15 Issue 3 Pages 687-690
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    Separation of particles by capillary hydrodynamic chromatography was studied experimentally. Measuring the retention time of a mono-particle system, it was shown that the ratio of retention time to mean residence time depended not only on the particle diameter but also on the flow rate of solvent. Resolution of peak was calculated from the chromatogram of a binary-particle system. The resolution of peak also depended on the flow rate of solvent.
    Download PDF (711K)
  • Ryuzo Ito, Yushi Hirata, Kunihiro Katsurada, Hiroaki Shigesada
    1989 Volume 15 Issue 3 Pages 690-694
    Published: May 10, 1989
    Released: October 21, 2009
    JOURNALS FREE ACCESS
    The separation principle of electrophoretic focusing of rare-earth metal ions by use of their complexes is described on the basis of the equations of ion transport, from which an analytical expression has been obtained for the concentration distribution in an electrophoretically separated zone. The concentration distribution can be well expressed by the Gaussian curve under the normal condition of the potential applied to an electrophoretic separator. Analytical expressions have been derived from this distribution to evaluate potential gradient, concentration gradient of a ligand producing metal complexes and width of fractionation outlet to achieve high purification of rare-earth ions. Using the complex stability data of EDTA, it is demonstrated that electrophoretic focusing has an excellent ability to separate the rare-earth metal ions. The analytical relations obtained in this study are of practical importance in designing and operating electrophoretic separators.
    Download PDF (751K)
feedback
Top