A theory of molecular diffusion in liquid is developed on the mechanism for ‘the diffusion coefficient’ asrismg from the sidestepping effect caused by the packmg, by taking the mean velocity of a molecule in liquids Into consideration.
By introducing the mean velocity (μ=energyy of translation/(viscosity×area of contact)) for the Peclet number (μD/D=11), the quantitative expression is obtained;D= (3/2) DkT/(11μA)(1)
where D, μ is diameter [cm] and viscosity [Poise] of a solvent, respectively, A [cm²] area of contact of a solute.
Eq.(1) is modified in order to apply for systems involving polar substances by use of the association parameter ∅_i;D=const.(∅^Aυ^A) ^(1/3)T/(∅^Bυ^B)(^2/3μ)(2) where υ_i is molar volume at T.
The association parameter ∅₆ is, also, specified from the solubility parameter δ_i and the nonpolar solubility parameter δ₈^d of a molecule by ∅_i=δ_i/δ_i^d (3)
Eq.(2) is in good agreement with experiment far strongly interacting solute solvent systems, by using const =1.84×10^-9.

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An experimental study was made of the diffusion of vapor into a stagnant binary gas mixtures by vaporization of liquid in the Stefan diffusion glass tube apparatus Theoretical diffusion rate was obtained from the Stefan Maxwell diffusion equations. The limits in which Wilke's equation can be applied were expressed clearly The experiments were carried out for C₆H₆-H₂-N₂ system The agreement between experimental and theoretical values was satisfactory Diffusion coefficients for C₆H₆-H₂ and C₆H₆-N₂ were 0.389cm²/sec and 0.0892cm²/sec at 30°C and 1 atm, respectively

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Adsorption equilibria of benzene vapor, ethane, ethylene and carbon dioxide on commercially available molecular sieving carbon were measured Those results showed that Dubinin equation did not fit well but Dubinin Astakhov equation was suitable for adsorption on molecular sieving carbon Exponent n in Dubinin Astakhov equation was determined to be 3 in the case of hydrocarbon adsorption and the effect of pore diameter on its value and characteristic energy of adsorption was discussed.

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An apparatus for measuring ternary vapor-liquid equilibrium of polymer solution was constructed and the equilibrium measurements were performed by the apparatus for three binary and two ternary systems which had polystyrene as a component.
The Flory-Huggins equation, which has one parameter for a binary system, was successful in expressing the experimental values for toluene-polystyrene and ethylbenzene-polystyrene systems, but the equation was not good for the solution of cyclohexanepolystyrene system which deviated considerably from athermal solution On the other hand, the Heil-Prausnitz equation, which contains two parameters for a binary system, was able to express satisfactorily all these three binary systems.
Experimental values of activities for the ternary system of toluene-ethylbenzene-polystyrene were finely expressed by the Flory-Huggins equation, but the values for the ternary system of toluene-cyclohexane-polystyrene were not expressed satisfactorily even by use of the Heli-Prausnitz equation The latter ternary system which was composed of polymer, good solvent and poor solvent may be too much non ideal to be well expressed by these equations.

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Salting out was tried to separate isopropyl alcohol-water azeotropic mixture and the 25 salts were examined to observe the salt effect on this system. Effective salts are K₂CO₃, K₄P₂O₇, K₂S₂O₃, K₃PO₄, which are more soluble in water than the other salts Among the four salts, the most effective one is K₂CO₃ on the standpoint of industrial interest Therefore, as basic data for the application of K₂CO₃ to the industrial salting out process, liquid liquid equilibrium for the isopropyl alcohol-water-K2CO3 system at 30°C was measured.
As a result, isopropyl alcohol-water mixture the concentration of which is less than 87.4wt% has been concentrated to 95.6wt% isopropyl alcohol.

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Absorption rates of pure carbon dioxide into aqueous ammonia solutions with a small amount of surfaceactive agent were measured in a liquid jet column and a wetted wall column Experimental results were analyzed with the penetration theory for gas absorption accompanied by chemical reaction Physical solubility of carbon dioxide in aqueous ammonia solutions was determined from the absorption rates measured in a pseudo first order reaction regime and shown to be considerably larger than the physical solubility in water The absorption rates obtained with ammonia solutions of which carbonation ratios were not so high, were in good agreement with the theoretical predictions for gas absorption accompanied by irreversible second order reaction with a stoichiometric coefficient of 2 when the variation of the interfacial concentration of carbon dioxide with gasliquid contact time was allowed for On the other hand, absorption of carbon dioxide into highly carbonated ammonia solutions was treated as chemical absorption with a reversible reaction having a large value of equilibrium constant and the absorption rates observed agreed with those predicted from the theory

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Heat transfer coefficients to helical coils immersed in a mixing vessel were measured with turbine and paddle impellers under various conditions. Pretty good correlations were made by the following equations containing impeller diameter (d), blade width (b), number of blades (n_p), impeller height (C), number of impellers (i), liquid height (H), blade angle (θ), coil loop diameter (D_c), outside diameter of coil tube (d_co) and vessel diameter (D).
(1) When the impellers locate inside the coil array under non baffled condition
(2) When the impellers locate outside the coil array under non baffled condition
(3) Under baffled condition
These equations are also valid for correlating data presented by previous authors.
Disagreement of the exponents for Reynolds number presented by previous authors (i. e. 0.5, 0.62 and 0.67) could be explained by the difference whether the discharge flow of the impellers strikes against the coil directly or not.
It was also observed that the attachment of baffles showed negligible effect on the heat transfer coefficient to cooling coils.

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Solubility curve and tie lines were determined for the systems acetic acid+water+alkyl acetate (ethyl acetate, n-butyl acetate, isoamyl acetate) at 25°C The plait point was located by the method of Treybal, Weber and Daley.
The liquid liquid equilibrium data were well correlated by Hand's plots and/or Hirata's plots.
Although alkyl acetate was a component of each ternary system, similarity of solubility characteristics was not found among the systems.

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Ternary liquid liquid equilibria of two systems con taming dimethylsulfoxide (DMSO) and isoprene were measured in order to test potentiality of using DMSO as a solvent in extracting isoprene from its C₅-monoolefine mixtures.
Equilibrium diagrams were presented for DMSO+isoprene+2-methyl-2-butene and +2 methyl-1-butene at temperatures of 20, 30 and 40°C The selectivity of DMSO for isoprene to other olefines and distribution coefficients were calculated from the data obtained The separation factors of DMSO as a solvent for isoprene are much lower than those for aromatic hydrocarbons in the same raffinate and it may, therefore, be difficult to separate isoprene from its mono olefine mixtures.

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The continuous gradation of particle size which occurs on the rotor wall of a gas centrifuge was applied to the analysis of particle size. As a result of the comparison with other methods of size analysis, it is apparent that this type of centrifuge is an of fective dry particle size analyzer. At pressures of less than 20 mmHg, the equations of motion can be expressed in terms of a dimensionless parameter S, and the computed values of the deposition angle coincided with the experimental results. Moreover, the calculating method of the size distribution has been simplified by the use of the two nomographs proposed here

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