From the viewpoint of film theory, mass transfer in liquid-phase molecular distillation is considered. The fol lowing results were obtained. 1) Evaporation rate (N) is given as shown in the following equation.
N=1/(1+ψγβB/D) C0ψγβ
where B is thickness of stagnant surface film; C is concentration of liquid; D is diffusion coefficient;β is maximum evaporation rate;γ is conversion factor;φ is evaporation coefficient. 2) 1/(1+φγβB/D) is defined as film coefficient of evaporation rate (E). E is increased as the liquid surface temperature is lowered. 3) Film coefficient of mass transfer is proportional to E^0.45.

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Experimental data were obtained for diffusion of gases in porous catalysts at 1 atm. and temperature range from 25 °C to -65°C. Effective diffusivity predicted by a few pore diffusion model were in good agreement with experimental values, except for two gas systems and lower temperature condition in which adsorption is significant. In a system with adsorbed gas, experimental diffusivities were found larger than predicted values. This is, however, not due only to surface diffusion effect because diffusivity was obtained from the non-adsorbed gas side, for example H₂ in H₂-C₂H₄ system.
Tortuosity factors were also obtained for non-adsorbed and adsorbed gas systems. Tortuosities measured in latter system were found about 20% less than those in former system.

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There has been no equilibrium distillation calculation available for non-ideal system, say for the system the relative volatility of whose components depends upon total pressure, temperature and liquid compositions. To solve this problem, a new general method is presented here. The principle of this iterative method consists of two mian trial calculation loops. The first is a material balance satisfying vapor-liquid equilibrium relationship for assumed liquid amount. The second is finding the liquid amount for which the calculated temperature is equal to the given one. The equation to correct the assumed liquid amount has a physical meaning. If the calculated temperature is higher than the given one, the liquid amount is corrected so as to increase and vice versa.
The relation between speed and precision of convergence is also discussed. The present method is available for the following systems: 1) non-ideal system 2) system at any temperature and under any pressure 3) system having azeotrope 4) when vapor-liquid amount ratio q is given. To test this method, numerical examples for 2, 3, 4, and 10 components systems were successfully carried out.

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An attempt was made to make an experimental investigation of the behavior of liquid droplets in the suspension polymerization of styrene. The change of average droplet diameter and its distribution were measured at various conditions of agitating speeds, dispersed phase fractions and stabilizer concentrations in the range of supposed coalescence control. A discussion of agglomeration and minimum concentration of stabilizer required is also included.
Consequently, it was found that the growth of the droplets is not significant when the concentration of stabilizer is more than the critical value, and that in the coalescence controlling region the rate of increase in average diameter is proportional to the square of the average diameter.

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The kinetics of the absorption of oxygen by sodium sulphite solution was investigated for the effects of the pH and concentration of cobaltous sulphate as the catalyst by the wetted wall column. In the ranges of sulphite concentration greater than 0.23mol/l and pH less than 9.2, the reaction rate was promoted by the concentration of oxygen within solution, cobaltous catalyst and hydroxylion, and these promoting effects were expressed with theequation for pH 7.5-8.5. A reaction mechanism has been proposed and the derived rate equation was in good agreement with the experimental results.

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For catalytic hydrodesulfurization of fuel oil in trickling packed-bed reactor, kinetic equations were derived, taking into account the processes of hydrogen dissolution into oil, diffusion in pores and intrinsic chemical reaction Experiments under the condition of 370°C-420°C in temperature and 51-131 atm in absolute pressure indicated that the desulfurization reaction of the Khafji residual oil was second-order with respect to sulfur concentration in oil. The effect of total pressure on reaction rate was also examined.

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Influence of air humidity on airborne dust generation was experimentally investigated with a fluidized bed, a spouted bed and a rotation mixer. White alundum (Al₂O₃) powder was used for a fluidized bed and ground Soma silica sand (SiO
2) was used for a spouted bed and a rotation mixer.
In the high-humidity region, the airborne dust generation rate Increased rapidly with decrease of air humidity. In the low humidity region, the increasing tendency of the rate slowed down. In this region, such phenomena as electrostatic charging of apparatus and adhesion of powder to wall surface were observed. Settling velocity distilbution of airborne dust particles generated by a rotation mixer was measured by a fractional settling airborne dust analyzer after Boose, C. and variation owing to air humidity was detected. Settling velocities of dust particles increased with air humidity. This might suggest the influence of humidity on the degree of agglomeration of dust particles. According to photo- and electron-microscopic observation, most of the particles settling in the fractional analyzer were agglomerated particles. On the surface of a single particle and in the void of an agglomerated partide, a large amount of ultra fine particles was observed.

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The droplet size distribution and its variance sprayed from hollow cone nozzles have been studied.
The size distribution of droplet collected in any local spraying place was approximately logarithmic normal. The total droplet size distribution was representable by the distribution at the maximum spray flux.
A semi-theoretical expression of the geometric mean diameter of droplets was introduced as a function of the injection pressure, the viscosity and the surface tension, considering the wave length and the sheet thickness at the break up point of moving liquid sheet.

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An experimental study of single-particle crushing under slow rate of compression was carried out by using spheres made of silica glass, borosilica glass and 6 kinds of minerals. The sphere diameters ranged from 0.5 to 3.0cm and the rate of loading was 3ton/min for silica and borosilica glass specimens and 0.3ton/min for 6 kinds of minerals. A summary of experimental results is as follows, 1) compressive strength of spheres was increased with decrease of their volumes, 2) the status of fracture was mainly transcrystalline type, 3) in case of hard material experimental values of strain energy agreed very well with theoretical values, 4) the strain energy was proportional to the (1-5/3m) power of volume of specimen, where m is the Weibull's coefficient of uniformity, 5) in the coarsesize range the energy rule of single particle crushing was according to Rittinger's law, 6) the reciprocal of size modulus of fractured product was proportional to the (5/3) power of the strength of specimen, 7) percentage of strain energy to industrial mill power obtained by work index was 2.71-42.0%.

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Stability of a dispersed phase continuous stirred-tank reactor in which an exothermic reaction occurs within dispersed drops is investigated and the effect of the coalescence and the redispersion of dispersed drops on reactor stability is discussed analytically.
Temperature of the dispersed drops is first estimated and then the maximum temperature and the run away stability criterion are obtained in correlation with the dimensionless parameters appearing in the fundamental equations.
Stability of temperature control system of the reactor is analysed through an approach of the local linearization of the fundamental equations. The analysis indicates that the effect of coalescence and redispersion becomes greater to the extent as the reaction order deviates from 1-st order, and that the effect is in opposite direction depending upon whether the reaction order is greater or smaller than 1-st.

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