The mutual solubility and equilibrium data for the ternary liquid-liquid systems ; 1) ethanol-water-o-xylene ; II) ethanol-water-m-xylene ; III) ethanol-water-p-xylene ; IV) ethanolwater-o-chlorotoluene ; V) ethanol-water-m-chlorotoluene ; VI) ethanol-water-p-chlorotoluene, are determined at 25°C. The mutual solubility data are correlated by plotting X_A/(1-X_C)against log X_C and the equilibrium data are correlated by the methods*of Bachman.Through these plots it becomes clear that the mutual solubility and equilibrium of ternary liquid-liquid systems are not affected by choice of ortho, meta or para isomers.

抄録全体を表示

Vapor-liquid equilibrium data at 760 mmHg were determined for the quaternary ethanol-isopropanol-ethyl acetate-isopropyl acetate system. Following hypothetical reaction is considered for the quaternary system.
EtOH+AcOiPr^→_←iPrOH+AcOEt The system could be treated as a system accompanied by chemical reaction. That is, vapor-liquid equilibria for the quaternary system could be calculated from the vapor-liquid equilibrium data for the binary and ternary systems at conversion 0 or 1. Similar results were obtained for the methanol-ethanol-methyl acetate-ethyl acetate system.

抄録全体を表示

The vapor-liquid equilibrium relations of the hydrogen-methane, the hydrogen-ethylene, The hydrogen-ethane, the hydrogen-methane-ethylene and the hydrogen-ethylene-ethane systems were determined by a static method at several temperatures from -25°C to -170°C and at pressures up to 100 atm. From the data obtained, features of the phase equilibria of hydrogen-light hydrocarbon mixtures are discussed.
The Benedict-Webb-Rubin equation was successfully applied to predict the vapor-liquid equilibria of the present systems above the normal boiling point of the heaviest hydrocarbon.

抄録全体を表示

Turbulent motion of particles suspended in water in a stirred tank and that of drops supplied to turbulent pipe flow of water are studied with emphasis on their scales. The scales considered are 1) sampling time scale : the very small time interval in which the displacement of a particle is measured, 2) measuring time scale : the time-duration during which a continuous measurement is run, and 3) sampling spatial scale : the width of a location in which the displacement of a particle is followed.
The effects of these scales on the magnitude of turbulence velocity components are examined, and the magnitudes are evaluated with a set of values of scales which seem most appropriate to each particle motion. The magnitudes are correlated uniformly in both dispersions with particle diameters and energy dissipation rates of surrounding liquid.

抄録全体を表示

Recirculation and the turbulence characteristics by jet flow confined in vessel were studied experimentally to examine Curtet-Craya''s theory.
The location of recirculation zone was first measured visually. The starting position of recirculation zone was well explained by Curtet-Craya''s theory.
Measurement of turbulence characteristics in the recirculation zone was carried out by hot-wire anemometer. These results show that increase in turbulence and high anisotropy of turbulence are caused by the low-frequency turbulence newly produced in the recirculation zone. Curtet-Craya''s assumption that turbulence is isotropic seems not to be appropriate in the recirculation zone. Turbulence intensities at the position of maximum recirculation flow correlated with Curtet number.

抄録全体を表示

A fully developed turbulent flow of an electrolyte solution in a porous-wall tube with suction or injection flow through the wall was experimentally studied.
The measurements of mass transfer rates at the wall were made by an electrochemical method. Reynolds number were varied from 7900 to 21, 000 and Schmidt numbers were 750, 1100, 1920 and 2100. The mass flow ratios ρv_w/ρU ranged from -2.13×10^-5 to 5.59×10^-5. It was recognized that mass transfer coefficients at the wall rise with increase of suction rate and fall with increase of injection rate. The results are in good agreement with predictions by film theory.

抄録全体を表示

Intraparticle diffusion parameters 15_eK/r² for adsorption of C₂H₄ or C₂H₆ on fixed beds of various porous catalyst particles ranging from 0.008 to 0.1 cm in radius were obtained from the analysis of breakthrough curves. In the case of catalysts having bi-disperse pore size distribution, the parameters are inversely proportional to the square of the particle radius r² in the region of larger particle sizes, and they approach certain constant values as r² decreases. These phenomena can be explained as follow : Diffusion of a gas occurs through macro-pores at first, and then the gas penetrates gradually into micro-pores. Thus the effect of pore diffusion on overall adsorption rate depends on the relative importance of macro- and micropore diffusion.
In the case of alumina pellets, which have monodisperse pore size distribution, however, intraparticle diffusion parameters are inversely proportional to r² throughout the region of particle sizes investigated.

抄録全体を表示

A similarity analysis is applied to steady cocurrent flows with a mobile interface, and a method is suggested to calculate the velocity profiles in both phases. With this method the velocity profiles and mass transfer coefficients are numerically obtained for a simple flow system. It is shown that, approximately, Sh∝√R_Lσ, and that the dimensionless velocity gradient at the interface can be reasonably neglected for mass transfer calculations.

抄録全体を表示

Effective diffusion coefficients in catalyst pellet for nonreacting and reacting systems, C₂H₄-He and C₂H₄-H₂, respectively, were measured in the same packed bed of catalyst by the use of the frequency response method. For the latter system the diffusion coefficient was also obtained from the effectiveness factor for the hydrogenation of ethylene. No appreciable differences were found between these values.
The effects of pore size distribution on the effective diffusion coefficients for nonreacting and reacting conditions were examined numerically for first-order reactions.For unimodal pore structures, the differences of coefficient for both conditions do not exceed 10% irrespective of size and width of pore distributions. This may also be the case for bimodal pore structure, when the coefficients are evaluated separately for macro and micro pores.

抄録全体を表示

Rates of oxygen absorption into water were studied in a rotating-disk gas-liquid contactor, in which liquid films were formed on the surface of disks rotating around the horizontal axis. When plain disks were used, values of the liquid-phase mass transfer coefficient k_L were lower than those predicted from the penetration model. However, with disks made of appropriate wire mesh, k_L, values agreed quite well with prediction by the penetration model for the range of gas-liquid contact time from 0.2 to 1.5 seconds.This type of gas-liquid contactor equipped with wire mesh disks seems to be a useful apparatus for studies of liquid-phase mass transfer in gas absorption.

抄録全体を表示

Three light source models, i.e., radial, specular, and diffuse line source models, are compared for light intensity profile, overall rate of reaction, and radial scale-up ratio of annular photochemical reactors, with the assumptions of constant absorption coefficient and constant quantum efficiency. The necessary condition for the radial light model to hold is that, when the ratio of inner radius to height of the reactor m, is 0.1, that of outer radius to inner radius ρ should be less than 3, and that when m is larger ρ should be close to 1. Published reaction data are analyzed according to this condition.

抄録全体を表示

An analysis of ligament-type disintegration was made by equating the rate of dissipation of kinetic energy, surface energy and viscous deformation energy of disturbance of the liquid film to the motive power by centrifugal force at the edge of a rotating disk.
The number of ligaments generated in disintegration of liquid film is given as a function of the Weber number and the stability number.
This analysis gives an interpretation on the basis of the energy balance for the experimental results by Hinze and his co-worker, who used a rotating cup and represented the same expression as the present paper.

抄録全体を表示

Statistical methods are applied to analysis of the aerosol concentration distribution in space and time, and the theoretical calculations are compared with the experimental results as follows :
i) A theoretical frequency distribution Eq. (20) of the aerosol concentration has been derived.
ii) The theoretical curve obtained by the substitution α=67 in Eq. (20) is in good agreement with the experimental results, using a stearic acid aerosol produced by a LaMer aerosol generator.

抄録全体を表示

A mathematical model of an air filter which is controlled by utilizing a pressure switch or a timer is formulated on the basis of some simple postulates. The dust-holding capacity, the renewal period, the fluctuation of pressure drop, the life time of a finite filter medium, etc., are numerically calculated for a wide range of practical conditions, and the merit of partial renewal, the comparison between pressure switch and timer types and the effect of length of medium on the performance of the air filter, etc., are discussed.These results are shown to be in good agreement with Higuchi''s experimental data.

抄録全体を表示

The role of the mixing process, when ethylene halohydrins were poured in highly viscous aqueous solutions of hydroxyl ions in an agitated vessel, was investigated. There were three steps in the mixing performance.
The first step was considered the decreasing process of the scale of segregation with the inter facial reaction. The interval of the first step was in general accord with the mixing time measured by conductivity method. The interval of the first and second steps was defined as the mixing time in chemical reaction system. Our experimental results showed the helical ribbon agitator is superior to the elliptic board agitator in mixing time with chemical reaction defined here.

抄録全体を表示

A sensitivity analysis method which is an extension of the conjugate direction method developed by Davidon, Fletcher and Powell is presented. Sensitivity means the change of an objective function caused by the deviation of independent variables in an arbitrary direction from the optimum point. Furthermore, by this method we can know whether a local optimum point has been really attained or not after termination of successive iterations.
A numerical example of successful application to an optimization problem in chemical engineering is shown.

抄録全体を表示

The applicability of the Benedict-Webb-Rubin equation to the vapor-liquid equilibria of hydrogen-hydrocarbon mixtures was studied. Nine binary and six multicomponent systems were tested over wide temperature and pressure ranges and the equation was shown to be successful. However, at low temperatures, errors became significant for heavy components.
The predicted K-values were compared with those from the Chao-Seader correlation, and the former was shown to be better in general than the latter.

抄録全体を表示

The collision and coalescence of drops are studied in turbulent liquid flow. From the standpoint of collision frequency, the random motion of drops is found quite analogous to that of molecules assumed in simple gas kinetic theory. The process of coalescence of drops is followed, and it is found that two drops will coalesce immediately on collision in the case when they will finally coalesce. The coalescence fraction may be determined by the kinetic energy at the instant of collision, but the fraction is surprisingly small and cannot accede to the order of 10^-1 in the range observed.

抄録全体を表示

To develop a design and scale-up procedure for continuous grinding equipment based on comminution kinetics, the steady-state hold-up of particles was analytically obtained in connection with several parameters. The optimum and the critical diameter of mills using grinding media are expressed as a function of a given duty and the parameters concerned. Calculated results are compared with experimental data previously reported by Mori et al.
In short, it is suggested that the configuration of mills should be determined by solving simultaneously the comminution kinetics and the flow of materials through a mill.

抄録全体を表示

A necessary condition for the stability of an adiabatic tubular reactor with recycle is presented in this paper when Peclet number for mass transfer is not equal to that for heat transfer and dead time for recycle is not negligible. The condition is derived from a necessary and sufficient condition under which a system of ordinary differential equations has no eigenvalues with positive real parts. The condition is described in terms of the relationship between the slope of the heat generation curve and that of the heat removal line at the points of intersection.

抄録全体を表示