The experiments were performed by applying step change of vibrating frequency in the perforated plate extraction tank. The drop size distribution and Sauter drop size(d32)were measured with photographic and light transmission methods. Experiments indicated that drop breakage only occurred during its collision with the hole of the plates. Therefore, the shear force adjacent to the holes of the plates should be considered as the drop breaking force. From this basic point of view, a new model of drop breakage rate has been derived. For the coalescence of drops in the liquid-liquid contactor, the drops must collide with each other with sufficient collision energy. An expression for binary coalescence rate of drops has been derived by assuming that the mechanism of drop collision in vibrating extraction tank is analogous to the collision between molecules in the kinetic theory of gases.

A simulation procedure based on Monte-Carlo method was used for simu-lating the processes of drop breakage and coalescence in a vibrating plate tank. Parameters for dispersion dynamics were derived by comparing the results of simulation with experimental data. Drop size distribution and Sauter mean diameter model were also fitted with experimental data. It can be seen that the log-normal distribution could be used to describe the experimental results fairly well. Relationship between Sauter mean diameter and geometrical factors, physical properties of the system and operating conditions has been obtained.

When the liquid is introduced into a vertical tube and heated to its boiling point, convective boiling occurs. If an inert gas is introduced at the bottom of the tube, it can be observed that the boiling vapor nuclei are not formed on the heating pipe wall and the evaporation of liquid takes place at the gas-liquid interphase instead. Such an operation is called Gas Carrying Evaporation(GCE). In this paper studied by visual observation and with an electric conductivity probe, the flow pattern transition was measured as a function of carrying gas flow rate, liquid rate and operating pressure and an empirical flow regime diagram was obtained. Moreover, the effects of various operating parameters on heat transfer in GCE were studied and the mechanism of the enhancement of heat transfer in GCE was analyzed. The following conclusions can be drawn from this study. In GCE,the heat transfer coefficient is higher than that obtained either in convective boiling or in gas-liquid two phase flow. It can be considered that there is a quick diffusion of liquid vapor at the initial instant with the result of lowering the gas-liquid interfacial temperature and enhancement of the heat transfer. The heat transfer in GCE may be considered as an overall effect of boiling, convective transfer and the enhancement by quick mass diffusion and can be correlated with dimensionless groups. The heating wall temperature will be lowered in GCE, so it can be applied to evaporation of heat-sensitive materials and to the evaporation of solutions which will form scales on the heating surface.

The electrostatic pseudo liquid membrane separation process, developed recently in this laboratory, is a novel chemical separation technology. It is an inter-disciplinary technique evolved from the combination of solvent extraction, liquid membrane and electrostatic techniques. It can be used to separate, purify and concentrate specific solutes from aqueous solutions. Therefore, it is suitable for the recovery of valuable metals from aqueous solutions in the field of hydrometallurgy including nuclear fuel recycling, and for the processes of waste water treatment. In this paper, the basic principles of electrostatic pseudo liquid membrane are discussed and demonstrated experimentally with Co2+ extraction by D2EHPA. The effects on Co2+ extraction by electrical field strength, extract-ant concentration and the flow ratio of feed to stripping solution have been studied. Experiments show that the once through extraction efficiency of Co2+ can reach 99% while Co2+ can be concentrated up to 40-50g/I. in the stripping solution.

A method for the determination oi the mass-transfer coefficients of vapor and liquid phases on the distillation trays-nonequilibrium-cell method is developed. In the model the tray is divided along the liquid flow direction into a number of cells, in each of which both vapor and liquid phases are assumed to be well mixed and the mass and heat transfer between these two nonequilibrium phases proceeds across the vapor/liquid interface. For each cell the mass and energy balance equations for each phase are connected by the mass and energy conservation relationships around the interface which is assumed to be in therrnodynamic equilibrium. For binary distillation, with given flow rates, compositions and temperatures at the inlet and outlet of tray, the model can be represented by (11×nce+ 2) independent equations with the same number of independent variables. The equations are solved to obtain the individual phase mass-transfer coefficient for both phases on each tray using the hybrid Newton method. The model can be used to determine the transfer coefficient-area products simultaneously for both phases on the basis of a single set of experimental data with both phase rate controlling system. On the other hand, the individual phase coefficients have to bo obtained separately with two sets of data each with one phase rate controlling system by the conventional "efficiency method (e. g. the AIChE model) (nce-number of cells per tray. )

The nonequilihrium-cell model described in part I is used to determine the binary mass-transfer coefficients of vapor and liquid phases on the bubble-cap and sieve trays. The coefficients determined by the model are compared with the AIChE correlations for the experiments of absorption of ammonia in air with water and of the distillation of methanol/water system under total reflux. For the one-phase rate controlling system-absorption of ammonia on bubble-cap trays, the model gives the same values of the gas phase mass-transfer coefficients as those from the AIChE correlation. However, for the two phase controlling system-distillation of methanol/water on sieve tray, the individual coefficients determined by the model are 20-70% higher than those from the AIChE correlations. The results show that the nonequilibrium-cell method can be successfully used to determime the mass-transfer coefficients on distillation trays, and it is more reasonable and convenient to use this method than to use the conventional efficiency method and chemical method.

Predictions on the solubilities of substances in supercritical fluids have to rely on the equation of state. Consequently, it is very important to develop an equation of state applicable to supercritical fluids, especially for fluids approaching critical conditions. The p-V-T properties of 10 substances CO2, G2H4, C3H8, etc. in the supercritical region were calculated by the RK, RKS, PR, CS-RK and CS-vdW equations of gases state and the calculated results were compared with experimental data. It was found that all these equations of state were not adoptable to the supercritical region, especially at the points approaching critical. A modified RKS equation of state, employing molecular thermodynamics, was suggested: This equation of state was used to calculate the p-V-T properties in the supercritical region and was found to be of good accuracy. In the region approaching the critical point, deviations in calculations by this modified RKS equation were much smaller than those of other equations of state.

The complex reaction kinetics of L-H. mechanism in triangular reaction of isomerzation of butenes has been investigated in a flowrecirculation glass reactor. X-ray analysis showed that the MoBiP2.2/SiO2 catalyst contained the phase of bismuth phosphate. The acidic concentration of the catalyst was titrated by butylamine with the method of adsorption of coloured indicator. The catalyst exhibited moderete acidity. The brousted and lewis acidity was measured by the infared spectroscopic method with pyridine adsorbedon catalyst. Gas-solid chromatography has been used to measure the heat of adsorption of 1-butene and 2-butene respectively. The dependence of the apparent activation energies on the intrinsical activation energies of the isomerization of 1-butene was discussed. The parameters of the kinetic equations were estimated with the mothod of orthogonal design. The kinetic equations for the formation of trans 2 butene and cis-2-butene respectively by isomerzation were developed.

The state-variable-network approach was proposed to estimate the parameters of the two-dimensional fixed number mixing pool model for simulating the fluid flow and mixing behaviors on a large tray. This method is clear in concept and more effective in conputation than the others.

The solubility of carbon dioxide in dimethylformamide at pressures between 207.21 and 1684.02 kPa and at temperatures of 15, 20,25,30,35,40 and 45℃, respectively, have been reported. An equation for the activity coefficient expressed by solubility parameters and taking excess entropy into consideration is presented in the payer.

The properties and behavior of Pd-carbon fiber deoxygenation catalyst and its carrier are measured and studied by employing low temperature N2 adsorption, thermal analysis, electronic macroscope, H2 chemisorption and dynamic analysis. The results show that high performance of Pd-carbon fiber deoxygenation catalyst is responsible for its physical and chemical characteristics. The resistance of mass transfer is much lower for the fiber catalysts than the granular ones. Heavy H2 spillover in the system of H2-Pd-carbon fiber may happen and H2-O2 reaction within the micropore of carbon fibers may possibly occur. The reaction between adsorbed oxygen and spillover hydrogen on the surface of the micropore may play an important role in the deoxygenation process of the fiber catalyst. Results measured comfirmed that the assumptions made in previous theoretical approaches appear to be valid.

In this article, the stability of four polymorphic modifications of copper phthalocyanine(α,β-,ε- and crystallization-resistant α-CuPe) in different organ- ic solvents and aqueous mediums are studied. The transformation and stability of the four crystalline powder samples in different atmospheres (N2, air, ammonia and HCl gas) are studied by X-ray diffractometry. The critical temperature and the initiation of crystal transformation from α to β form are determined.

Volumetric mass transfer coefficient kL a was determined by the unsteady state oxygen absorption method for a O2-KCl solution system. Changes of the dissolved oxygen concentration in the bulk liquor with time was monitored through a dissolved oxygen probe. Various effects, such as gas pressure, impeller rotational speed and liquid ratio, on the mass transfer coefficient kL a were investigated. It was found that at high pressures, with the increase of gas phase density, gases tended to form small bubbles in the liquid phase, and as a result a higher rnsss transfer coefficient in the agitated vessel was visualized. When the liquid ratio was 0.5, and the employed tunbins impeller diameter ratio 0.8, about 20% increase, in the value of kLa was obtained when operating under a pressure of 36 atm. instead of atmospheric.

In this paper, the material balance equation on fixed bed adsorption col-umn was simplified by neglecting the longitudinal dispersion effect. The parameters of adsorption and transfer were estimated by transfer function method on pulse-response experiments. The adsorption equilibrium constants and overall mass transfer coefficients of C8 aromatic isomers obtained from the experiments were agreed with the breakthrough curves of adsorption and desorption.

Separation of quinary gas mixture(H2:36% ,CO:50%,CH4:0.8%, CO2:12%, H2S:1.2%) by pressure swing adsorption processes has been studied to obtain high purity H2 product (H299.999%). The effects of operation conditions on separation were also studied. The experimental data are predicted by both bi-disperse pore diffusion model and equilibrium model. The predicted results are in good agreement with the experimental data.

At 60℃, the total pressure of dimethylformamide with styrene and o-xylene respectively was measured. A nonathermal associated solution model Was used to treat the pressure-composition data, and the associated constants were listed. It has shown that this model is better than the regular associated model for the systems in which the mole volumes of the components of the binary solution are quite different. The calculated results are in agreement with the experimental results of vapour-liquid equilibrium by flowing method at constant temperature.

Synthesis of ultrafine Si3N4 powders with radio frequency plasma was described. The design and the determination of the related parameters of the reaction system were discussed. "Magnetic pumping" was employed to introduce the reaction gases into the fireball of the plasma and H2 was used to regulate the oscillator-load matching. The reaction process was studied and the relevant data were computed for the preparation of ultrafine Si3N4 powder.

The hydrodynamic and mass transfer performance of conjugate ring, a high efficient random packing, developed in China, was summarized. The constitutional characteristics of conjugate ring was presented. The experimental results have shown that the pressure drop per unit height of column packed with plastic conjugate ring with diameter of 38 millimeter is 40-45% less than that of Cascade mini-ring and 50-55% less than that of Pall ring with same nominal diameter. The height of a mass transfer unit of conjugate ring is 15% less than that of Cascade mini-ring and 30% less than that of Pall ring. The experimental results show that the performance of conjugate ring, i. e. hydrodynamic and mass transfer performance, is better than that of Cascade mini-ring and pall ring respectively.