JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
Print ISSN : 0021-9592
Volume 7 , Issue 3
Showing 1-16 articles out of 16 articles from the selected issue
  • KUNITARO KAWAZOE, MOTOYUKI SUZUKI, KAZUYUKI CHIHARA
    1974 Volume 7 Issue 3 Pages 151-157
    Published: July 31, 1974
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    Chromatographic measurements were made for nitrogen adsorption on molecular-sieving carbons at 60, 100 and 150°C for several different nitrogen surface coverages.
    Apparent adsorption equilibrium constants were determined from the retention times of the peaks for different concentrations, and the adsorption equilibrium isotherms were then determined. The peak width gave the intra-microparticle diffusivity where the effects of all the other possible transport processes were taken into account.
    The strong dependence of the diffusivity on the amount adsorbed was explained in terms of chemical potential gradient as a driving force of the diffusion.
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  • KUNITARO KAWAZOE, TOSHINAGA KAWAI, YOSHITOMO EGUCHI, KIYOSHI ITOGA
    1974 Volume 7 Issue 3 Pages 158-162
    Published: July 31, 1974
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    Adsorption equilibria of various gases and vapors on molecular-sieving carbon were measured. The data were correlated by the Dubinin-Astakhov equation: W=W0 exp [-(A/E0)n], and the characteristic values of adsorption were determined. The equation covers the adsorption of various kinds of gases and vapors. The exponent n in the equation is about 3 for organic gases and lies between 2 and 3 for inorganic gases. The charactersitic energy of adsorption is expressed as E=β(ΔH0)s, where (ΔH0)s is the standard heat of vaporization of a standard material such as benzene and the coefficient β is approximately equal to the ratio of the parachor of the adsorbate to that of the standard material. Studies are made of three different types of deviations from the Dubinin-Astakhov equation, observed in the course of experiment.
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  • TOKURO MIZUSHINA, HIROMOTO USUI, TAICHI TOSHIBA
    1974 Volume 7 Issue 3 Pages 162-167
    Published: July 31, 1974
    Released: March 27, 2006
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    An analysis similar to the van-Driest damping factor model for Newtonian fluids results in a viscoelastic damping factor for turbulent pipe flow of dilute polymer solutions. The turbulent relaxation time λt which must be used in the viscoelastic damping factor model is defined and correlated empirically. The present analysis is tested with the measured velocity distribution in the unsaturated drag reduction region, and friction factor in the unsaturated and saturated drag reduction regions. A comparison of the present model with two other well-known models, the elastic sublayer model of Virk et al. and the thickened laminar sublayer model of Seyer and Metzner, is made at the maximum drag reduction asymptote. From these comparisons it is concluded that the present model is valid to predict the friction factor and the velocity distribution in both the unsaturated and the saturated drag reduction regions.
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  • T. R. BOTT, M. WHYSALL
    1974 Volume 7 Issue 3 Pages 167-172
    Published: July 31, 1974
    Released: March 27, 2006
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    The behaviour of three binary mixtures benzene-n-heptane, n-heptane-n-propyl iodide and dodecane-quinoline, in a thermogravitational diffusion column have been studied. Results covering a wide range of initial composition are recorded. It has been found that the ideal parabolic curve relating separation and initial mixture composition is distorted; greater distortion occurring when "ring" compounds are present. The non-ideal behaviour is attributed to molecular "mobility" differences.
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  • MASASHI ASAEDA, MORIO NAKANO, RYOZO TOEI
    1974 Volume 7 Issue 3 Pages 173-180
    Published: July 31, 1974
    Released: March 27, 2006
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    Diffusion of gases through packed beds of particles under uniform total pressure is studied analytically by using the rigorous kinetic theory of gases with the two-sided Maxwellian velocity distribution functions and Maxwell''s transport equation. Attention is paid to the solid parts of the packed beds, although most investigators have concentrated on the space structures to obtain a pore model. With some abbreviations the present results are quite similar to those of Evans et al., which were derived from the macroscopic multicomponent diffusion equation by considering the particles as giant molecules. But in the Knudsen diffusion region their results are about 2.4 times larger than the authors'' or the experimental results. The present treatment is considered to be more adequate and general than that of Evans et al. and others. To obtain experimental confirmation of the analytical results a simple method for measurement of the effective diffusivities and flow permeabilities of gases through porous media is proposed by using the wellknown relation, -NA/NB=(MB/MA)1/2, which is also derived from the present treatment. The experimental results by this method are in relatively good agreement with the analytical ones obtained here. This is perhaps the first direct experimental confirmation of the dependency of the mean effective diffusivities of gases through porous media on composition.
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  • TOYOHIKO HAYAKAWA, MASAKUNI MATSUOKA
    1974 Volume 7 Issue 3 Pages 180-186
    Published: July 31, 1974
    Released: March 27, 2006
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    As a fundamental study of growth rates in zone refining, the growth rates of crystal layers of sodium thiosulfate on a cooling surface placed at the bottom of an agitated tank were measured and compared with calculated growth rates in which the assumptions were made that the growth process of crystal layers involves mass transfer, heat transfer in the liquid and in the crystal layer and surface rate process. Good agreement between them was obtained except for the initial period, in which the crystal grew rapidly with very rough interfaces. This difference was explained as a result of the inclusion of the mother liquor at the growing interface.
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  • TSUTOMU HIROSE, MIKIO TODA, YUJI SATO
    1974 Volume 7 Issue 3 Pages 187-192
    Published: July 31, 1974
    Released: March 27, 2006
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    Volumetric absorption coefficient (ka)lg, specific interfacial area alg and mass transfer coefficient klg were measured for two-phase cocurrent flow of O2-water and CO2-NaOH systems in a column packed with glass spheres of 3 different sizes (2.59-12.2 mm). Values of (ka)lg observed were so high as to be that can be hardly attainable in conventional gas-liquid contactors. This is due to large alg of small bubbles dispersed in liquid where alg very often exceeds the geometrical surface area of packing. Values of klg range from 2 to 8×10-4m/sec, which are comparable to that of circulating bubbles in the usual systems. The effect of superficial gas velocity on (ka)lg and alg is much greater than that in a countercurrent packed column, while the effect of liquid velocity is approximately same. A liquid-phase energy loss El per unit volume of liquid contained in a bed was newly defined as a measure of microscopic flow intensity and was used for discussion and correlation of mass transfer properties. It was found that the bubble diameter is proportional to El-2/5.
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  • RYOZO TOEI, KAZUHIRO NAKANISHI, MORIO OKAZAKI
    1974 Volume 7 Issue 3 Pages 193-200
    Published: July 31, 1974
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The rate of consecutive hydrogenation of acetylene with nickel-on-kieselguhr catalysts was studied both experimentally and theoretically under such conditions that the effects of intraparticle diffusional resistance of micro and macro pores could be ignored, in order to examine the intrinsic reaction mechanism in detail, and the selectivity for a consecutive gas-solid catalytic reaction was investigated.
    It was found that the rate steps on the catalytic surface, especially the desorption step of intermediate product and surface reaction step, played a predominant role in the selectivity.
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  • TERUKATSU MIYAUCHI
    1974 Volume 7 Issue 3 Pages 201-207
    Published: July 31, 1974
    Released: March 27, 2006
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    A concept of successive contact mechanism has been introduced to account for the influence of dilute phase catalyst on overall conversion of reaction in fluid beds. A theory has been given, as a simpler version of the proposed model, for an isothermal and irreversible first order reaction. To test the concept, axial distribution of bed density has been measured for small scale fluid beds. Rather freely suspended catalyst particles are observed in the dilute phase in enough amount to contribute to the progress of reaction. The theory has revealed for the progress of reaction that the catalyst particles located in the bubble phase are interchangeable with those suspended in the dilute phase and vice versa.
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  • TERUKATSU MIYAUCHI
    1974 Volume 7 Issue 3 Pages 207-212
    Published: July 31, 1974
    Released: March 27, 2006
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    In a companion paper (J. Chem. Eng. Japan, 7, 201, 1974), a concept of the successive contact model has been presented to account for the extent of catalytic reaction in a fluid bed. The model has been tested here for its soundness by comparing the behaviour of model with catalytic reaction data available so far.
    An apparent fraction of catalyst μ* in the bubble phase for catalytic hydrogenation of ethylene is shown to be reasonably well estimated from catalyst distribution in the dilute phase. The model provides a sound explanation for an apparent anomaly of μ* being fairly greater than unity in some data. Influence of bed design and operation on selectivity of a given catalytic reaction is briefly given for fluid beds.
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  • SHIGEO GOTO, MASAKAZU MATSUBARA
    1974 Volume 7 Issue 3 Pages 213-218
    Published: July 31, 1974
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The optimal solvent flow pattern for multistage reactors with extraction is investigated. The general structure is considered by introducing structure variables and is optimized by use of the method of Goldfarb et al. Numerical calculations are carried out for parameter values tentatively chosen. The results indicate some basic features of the optimal solvent flow pattern. Some qualitative considerations suggest that these features will probably be the general properties of the optimal pattern.
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  • EUI SARASHINA, JUNICHI NOHKA, YASUHIKO ARAI, SHOZABURO SAITO
    1974 Volume 7 Issue 3 Pages 219-222
    Published: July 31, 1974
    Released: March 27, 2006
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  • TERUO TAKAHASHI, YASUHARU AKAGI, Kozo FUJITA, TAMIYA KISHIMOTO
    1974 Volume 7 Issue 3 Pages 223-225
    Published: July 31, 1974
    Released: March 27, 2006
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  • A. B. PONTER, S. VIJAYAN, K. CRAINE
    1974 Volume 7 Issue 3 Pages 225-229
    Published: July 31, 1974
    Released: March 27, 2006
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  • MOMPEI SHIRATO, TOSHIRO MURASE, ATSUO TOKUNAGA, OSAMU YAMADA
    1974 Volume 7 Issue 3 Pages 229-231
    Published: July 31, 1974
    Released: March 27, 2006
    JOURNALS FREE ACCESS
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  • OSATO MIYAWAKI, HIROO TSUJIKAWA, YUZO URAGUCHI
    1974 Volume 7 Issue 3 Pages 231-233
    Published: July 31, 1974
    Released: March 27, 2006
    JOURNALS FREE ACCESS
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