The authors have proposed a simple procedure by which, utilizing the activity coefficients in the infinitely dilute binary solution, the Wilson, NRTL and Heil parameters can be evaluated without difficulty, The possibility has been shown that multiple solutions exist if the activity coefficients in the infinitely dilute binary solution are used. Also shown are the regions of multiple solutions of the Wilson, NRTL and Heil equations on the (γ₁⁰, γ₂⁰), (Λ₁₂, Λ₂₁), (T₁₂, T₂₁) and (τ₁₂, τ₂₁) plane, and graphs which aid to select the appropriate solution among multiple solutions. By the method described above, the authors evaluated the parameters for the acetone-chloroform and the acetone-methanol binary systems.

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The effects of radiation on the temperature distributions in the static packed beds was studied. The temperature distributions were analysed numerically for two cases in applying (i) the effective thermal conductivity and (ii) the radiant heat flux involving the wall effects, and the two results were compared with the experimental results (10mm and 15mm kaolin balls, heating temperature ranging from 60 to 590°C. Consequently, under the present experimental conditions, it was found that there was little difference between the heat transfer rates obtained from (i) and kii), but with respect to the temperature distribution the results of (i) showed fairly good similarity to the experimental results and the model applying (i) was more adequate, and that the temperature gradients, especially in the neighbourhood of the heating plate, became steeper with increasing the heating plate temperature.

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A characteristic difference in frequency transfer functions for chromatographic reactor obtained for uniform and bimodal pore models is elucidated. Frequency response experiments on the hydrogenation over different sizes of catalyst gave results which could be explained well only by the bimodal pore model. A method to estimate effective diffusion coefficients in micro and macropores under reaction conditions was also presented. The coefficients obtained by the method agreed fairly with estimated values from pore size distribution curve of the catalyst.

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The rate of absorption of light energy greatly affects the rate of photochemical reactions. As it is too complicated to solve general design equations exactly, three simpler approximations are set up. Results by one of the approximations show that the change of light intensity during the reaction is negligible if optical thickness τ≤5. The condition on which the other approximations can be applicable are described. Experimental data are in agreement with calculated values.

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It was recognized experimentally in a vertical moving bed that a radial normal stress acting on an element in the bed began to increase in intensity with radial distance from near the edge of plug flow region (constant velocity region) into a vertical wall, developed into a maximum value on the wall, and that the radial distribution of vertical velocity showed a great reduction in velocity only near the wall although a velocity was gradually reduced apart form the wall.
On the other hand, the radial normal stresses in the plug flow region and on the wall and radial distribution of vertical velocity were respectively predicted on the basis of plasticity theory in which stress and velocity characteristics coinside, and compared with experimentally determined characteristics. As a result of it, it was concluded that each radial normal stresses computed by theory reasonably agreed with experimental ones, and that the existance of discontinuity of vertical velocity at a position in radial distance was predicted by theory and experimentally determined velocity field could be interpretted as discontinuity.

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Studies were made on the transfer rate of oxygen into sodium sulphite solution in the horizontal stirred vessels. Apparatus used were cylindrical vessels, sized D_t=10.6-18.4cm in diameter, agitated by turbine type impellers. Results obtained were as follows:
1) In the state A₁, in which the liquid is splashed violently by the impeller in the vessel, over-all volumetric absorption coefficient is obtained to be linear with Froude Number.
2) It is most effective for absorption to operate in the A₁ state. In this state, the correlation between power consumed per unit volume of liquid P_v, and the coefficient K_G·α was expressed by
(oxygen-sodium sulphite solution) where, ε is the ratio of the volume of liquid to that of vessel.

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A rotational vane type scrubber which was built with three units of a perforated plate and a rotational vane was tested. It showed a constant and good efficiency through a wide range of liquid-gas flow ratio. In connection with the above experiment, the experiments using each unit, i. e. a vane, a rotational disk and a perforated plate were carried out. From these experimental results and theoretical view points, an idea of the effect-coefficient was introduced for each unit. Semi-theoretical analysis was tried by using these effect-coefficients.

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