An improved Stefan method was used to measure diffusion coefficients of carbon disulfide in several gases at 1 atm and at temperatures from - 10°C to 40°C at intervals of 5°C. Gases used were hydrogen, helium, nitrogen, air and argon, respectively. Values of diffusion coefficient for each system at 25°C were as follows: CS₂-H₂: 0.455±0.002, CS₂-He: 0.415±0.000, CS₂-N₂: 0.1103±0.0003, CS₂-Air: 0.1085±0.0001, CS₂-Ar: 0.0963±0.0002 cm²/sec. In the region measured, the temperature exponent for each system lies between 1.689 and 1.755.

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The diffusion coefficients of radioactive carbon dioxide (¹⁴CO₂) in nitrogen and in mixtures of carbon dioxide with nitrogen were measured at temperatures of 25, 50, and 75°C and at pressures ranging from 15 to 250 atm with an error of 3%. Mole fractions of nitrogen in the mixtures were 0.741, 0.515, and 0.238. The measurements were made through a plug of porous bronze in a diffusion cell of two-chamber type by using radioactive tracer technique. The diffusion coefficient-density products decreased slightly with increasing density or remained nearly constant. The diffusion coefficients at high pressure obtained in this study agreed fairly well with those calculated from the generalized chart, which was prepared from the correlation of the experimental data. The binary diffusion coefficients of a trace of radioactive carbon dioxide in nitrogen at high pressure could be predicted by a modified Enskog-Thorne''s theory.

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Vapor-liquid equilibria for two binary systems, at 760 mmHg and 1000 mmHg, were determined from boiling point measurements for the systems, chlorodifluoromethane (R-22)-benzene, R-22-cyclohexane. Liquid-solid equilibria and vapor-liquid-solid equilibria were also measured for those binary systems and the data were correlated using the Wilson equation.

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Amounts adsorbed on Molecular Sieving Carbon particles from several binary mixtures of non-aqueous chemical reagents were studied. Mixtures consisted of two different groups of reagents> namely, the one which was supposed to be accepted by micropores of the above adsorbent (believed to be about 5 Å in width) and the other which was not.
Bi-component equilibria, represented as a combination of individual Freundlich isotherms, were found to explain the observed results, and constants in the isotherms were determined.
Constants k₁ and k₂ were interpreted considering adsorption in micropores and macropores as well as physical properties of adsorbates.
Prediction of isotherms was tried for new systems. The results were satisfactory.

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The minimum air velocities required to keep particles from depositing on the bottom of a pipe are measured experimentally for 19 groups of spherical particles ranging from 20 to 1600 microns in three pipes of 20, 26 and 49 mm I.D. It is found that there is a substantial difference in the effect of particle size between fine- and coarse-particle suspensions. This difference is explained theoretically by means of numerical simulation on a digital computer based on the previously proposed ellipsoid bouncing model. A general correlation is presented to predict the minimum transport velocity over a wide range of particle size, in which an empirical equation for the distinction between the fine- and the coarse-particles system is included.

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Rates of the mass transfer in both continuous and dispersed phases were measured on single non-oscillating liquid drops moving through quiescent liquid field at Reynolds numbers ranging from 40 to 1200. The mass transfer experiments of both phases were performed on systems having high interfacial tension and iodine was used as the transferred material. For the mass transfer rate in the continuous phase, the experimental data are compared with analytical solutions obtained by use of the interfacial velocity of a drop proposed by Winnikow and Chao. For the mass transfer rate in the dispersed phase, the measured results are examined in the light of some theories proposed by other investigators. In both cases, the agreements between the experimental and the theoretical values are not satisfactory. Empirical equations for mass transfer coefficients in continuous and dispersed phases are obtained for the region of the intermediate Reynolds numbers.
The drag coefficients of the drops were also measured. Although the experimental values are higher than predicted by Winnikow and Chao, the data show good agreement with the values from the literature.

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The local and average mass transfer coefficients to a rotating sphere were measured by electrochemical method, when the angle α between the axis of rotation and the direction of the uniform stream were both 45° and 90°. For measurements of the local mass transfer rates, circular isolated electrodes of 2 mm dia. were used, and the time averaged values and the variations of the local mass transfer rates were obtained by processing the signals from each isolated electrode during some revolutions. Moreover, on the basis of the measurements of average mass transfer coefficients, new empirical equations were obtained with which they have been correlated well for α=0°, 45° and 90°.

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A new correction factor (η) for reaction rate has been defined. It is analogous to θ for correcting molal flow rates in the multi-θ method of convergence. Then a new calculation method with two such kinds of the independent variables as θ and η has been developed for solving reacting distillation problems at the steady state and at the unsteady state.
Convergence is obtained without difficulty in the case where vapor liquid equilibrium ratios may be formulated as a function of temperature only. However, in the case of calculations based on experimental data in the esterification systems, the values of Δη and Δη resulted from the Newton Raphson''s method have some time a large number. Therefore the correction method for these by use of arctangent function has been proposed in order to avoid divergence.
This new calculation method is called "Multi θ-η method of convergence".

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Fourier analysis for the parameter estimation in adsorption chromatography is, in practice, by no means equivalent to time-domain fitting, though Parseval''s theorem guarantees such relation. To reduce the effect of the tail of the response curves, the RTD curves are weighted with an exponential function, and then Fourier transformed. Intraparticle diffusivities, adsorption rate and equilibrium constants are successfully determined by this method, and comparisons are made between weighted and un-weighted results.

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Three normal and branched alkane mixtures: n-pentane+n-hexane+n-heptane, 2-methylbutane+2-methylpentane+2-methylhexane, and 2-methylbutane+n-pentane+2-methylpentane+n-hexane+2-methylhexane+n-heptane were pyrolyzed at 700°C under atmospheric pressure. The alkane mixtures were diluted by nitrogen so as to give almost the same partial pressure for each component as that in the commercial cracking of naphtha, and the product distributions over a wide range of conversions are presented.
A simulation model for the product distribution, which has been proposed for pure alkane in a previous study, was applied to the pyrolysis of alkane mixtures by taking into account the interaction between coexisting components. It was found by comparing with the experimental results that the present simulation model can be applied to simulate the product distributions over a wide range of conversions for normal and branched alkane mixtures.

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A fairly rapid chemical reaction, i.e., hydrogenation of ethylene by palladium catalyst, was carried out at a room temperature in a two dimensional fluidised bed with a perforated plate distributor. The results were considerably affected by the behaviour of the bed near its bottom. The measured hydrogen conversion was compared with that predicted by the so-called "coalescence model". Consistency of the experimental and calculated results was fairly good.
The significance of various parameters included in the model was also investigated. The parameters examined were the gas interchange coefficients, the volume fraction of particles in the bubble, and the gas flow rate as bubbles.
In conclusion, it was pointed out that the deviation of gas flow rate as bubbles from that predicted by the two phase theory at the bottom of bed affected significantly the conversion of a rapid chemical reaction.

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The cross-sectional and axial velocity profiles and temperature distributions in a horizontal epitaxial reactor were calculated numerically from fundamental equations under certain assumptions. Streamlines in the cross-section showed similar pattern over the whole range of Gr, but the value of stream function was affected by Gr. The axial velocity profiles were quite different from that of parabolic flow when Gr was larger than 10⁴. The temperature distributions in a cross-section of the channel became uniform when Gr was large.
In order to check the calculated results, the axial velocity profile and the temperature distribution were measured in this reactor under the same conditions as those of this calculation. The calculated velocity and temperature were a good approximation of the experimental ones.

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Concentration distributions of reactant and mass transfer coefficient in a horizontal epitaxial reactor were numerically calculated from fundamental equations under some assumptions in the case of mass transfer rate control. The concentration distribution in the cross-section of the channel became uniform when Gr and the distance from the leading edge were increased or the feed rate of gas was decreased. To check the calculated results, carbon plates were burned in this reactor under the mass transfer rate control and local concentration of carbon dioxide was measured. The calculated concentration and mass transfer coefficient were a sufficiently good approximation to the experimental ones.

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A formula for the maximum stable drop size has been derived theoretically, by taking into consideration the effect of the dispersed-phase viscosity. The derived formula indicates that the controlling factors of the maximum stable drop size are the Weber Number and the viscosity group which is defined as the ratio of the viscous stress to the stress of interfacial tension. The validity of the formula was confirmed experimentally over a wide range of dispersed-phase viscosity.

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