The influence of FeO content in the original composition of catalyst on the catalytic performance under high pressure was studied. The FeO catalyst with the Wustite structure(Fe1-xO, 0. 04≤x≤0. 10) was found to have the highest activity, which is opposed to the classical conclusion that the catalyst manufactured from reduction of magnetite (Fe3O4) has the best performance. Our experiments showed that the FeO based catalyst is a new-type of industrial ammonia synthesis catalyst with the highest activity, the lowest active temperature and the fastest rate of reduction.

The apparent kinetics of methanol synthesis from the gas mixtures containing CO, CO2 and H2 was studied in an internal recycle gradientless reactor. A commercial copper based catalyst, in full size particle form, was used with the experimental conditions similar to the operation range of an industrial reactor. The kinetic performance of the reaction system is described in terms of the rate expressions of two reactions.

One and two dimensional psedo - homogeneous models for Lurgi - type of methanol synthesis reactor were developed on the basis of experimental studies on the apparent kinetics of methanol synthesis on a commercial copper catalyst, MK - 101, and effective heat transfer performance in a small diameter fixed - bed. By means of the models, a series of operation performances of the reactor for different catalys ages were simulated and optimum operating parameters were predicted.The results obtained from simulation computations are in good agreement with those measured from a production plant.

According to the principle of lumping and reaction mechanism, a sixteen-lump kinetic model for catalytic reforming is developed, The model is simple, suitable for reforming process of various production plans, and has good flexibility and fittability

Six typical dynamic distillation models based on the published steady state models are established. The simulation of open - loop response of a depentanizer is used for comparison. The results show that the non- equilibrium effect and the inertia effect in an actual column are two important factors which can greatly influence the simulation of dynamic response process. Morever, the inertia effect seems to be more significant. Since both effects are considered in the proposed dynamic three - dimensional non - equilibrium mixing- pool model, it is believed to be most suitable to simulate the dynamic behavior of an industrial distillation column.

The parametrically sensitive point of a reactor was proved to be an inflection point of the hot spot locus by taking the definition of parametric sensitivity as the theoretical basis and mathematical starting point. The upper limit of the safe operation temperature was derived with respect to a one dimensional paeudo - homogeneous plug flow reactor with constant wall temperature, in which a first order reaction was carried out. With regard to the relation between the hot spot on the critical operation curve and the inflection point on the supercritical one, a criterion of the safe operation of reaction systems is obtained. This formula agreed well with the experimental data of El - Swai et al.

An experimental study on the gas dispersion behavior of cocurrent downflow gas-solid suspension in a 140 mm i. d. circulating fluidized beds (CDCFB) using the steady-state tracer method is presented. The influence of gas velocity, solids circulating rate and particle density on radial gas dispersion has been examined. Gas dispersion can well be described by eddy diffusion mechanics and a proposed two dimensional dispersed plug- flow model fits the experimental data very well. The correlation Per = 4. 35× 10-3Re0.95ε-73.4(while 1>ε>0. 99) for radial diffusion coefficient is obtained. It is found that the obtained axial diffusion coefficient in the CDCFB is much lower than that in a circulating fluidized bed.

A modified free volume model of diffusion has been developed to interpret transport phenomena in gel and immobilized cell matrix. With a set of formulas deduced from the model, the dependence of the effective diffusivity on such factors as gel composition (monomer concentration and crosslinking degree), cell loadings and temperature can be correlated by four linear relations.

The validity of the modified free volume diffusion model proposed in the previous paper ( I ) was tested for the interpretation and correlation of data on diffusion in polyacrylamide gel and immobilized yeast cell matrix. The effects of monomer concentration, crosslinking degree, temperature, diffusant size and cell loadings on the effective diffusivities of the diffusants in the above media were quantitatively correlated and qualitatively explained quite well with the model. Good agreement between the regressed equation predictions and the experimental data was obtained. Some semi- empirical equations were also obtained to relate the effective diffusivity in the gel to the composition of the initial solution.

A new scheme based on the fundamental postulation in statistical mechanics for perturbating molecules to create the Markov chain in Monte Carlo calculation was proposed. The new method can be used to simulate, in only a single box, phase equilibria of fluids including interfaces. Furthermore, for pure fluids, simulation can be implemented simply in the canonical ensemble. Simulation of pure square - well fluid at different temperatures by applying our new method gave the coexistence densities of bulk phases, the density profiles and chemical potentials along the z axis. In addition, our present study shows that the traditional Metropolis technique is not suitable to the simulation of such heterogeneous systems.

Double diffusive convection during static crystallization was studied. A Laser Swept Velocimetry (LSV) was used to measure the thermo - solutal convection velocity vector field. A mathematical model for static crystallization based on the reassessment of Bennon and Incropera model was derived, and the continuum conservation equations were solved with SIMPLER algorithm. The comparison of simulated and experimental results was examined as discussed. Although the experimental temperature, concentration and velocity profiles were in good correspondence with the calculations, the experimental fluid flow field was likely to be more complex than the somewhat idealized system simulated in this work. It was also shown that the low densiy liquid layer with low temperature in the mushy zone would result in the initiation of double - diffusive convection. With the development of such a convection, the flow velocity, temperature and concentration distributions showed salt fingers pattern. Double diffusive convection would also result in the formation of channel flow in the mushy zone.

An investigation on the local heat transfer coefficient of a helically segmented finned tube surface in a tube bundle was conducted by experiment in cooperation with numerical calculation. In the experiment, the thermal couples were embedded only at an angle with the tube to be tested, then the temperature distribution around the tube was measured by revolving the tube under a certain experimental condition. On the basis of the experiment, the local heat transfer coefficients at different angles of the test tube surface for different experimental conditions were obtained by solving a set of two- dimensional finite difference equations. The results were fitted and the correlation equations for predicting the average and local heat transfer coefficients for helically finned tube in the tube bundle over the experimental range of Re = 20000-80000 were presented.

An experimental investigation of pool boiling heat transfer is carried out in a horizontal tube bundle with 8 rows and 3 columns of tubes, and a pitch - to - diameter ratio of 1. 667. The working fluid is R-113. Heat transfer coefficients are measured for each row of tube, and it is found that the heat transfer coefficient increases for higher heat flux and higher position in the tube bundle. The measurements show that there exists a large bundle effect. In addition, boiling curve hysteresis in tube bundle is found. The correlations of boiling heat transfer coefficients are obtained.

The separation mechanism of high performance capillary electrophoresis was studied in light of chromatographic separation principle and by considering the effects of molecular diffusion, injection and power dissipation. The expression obtained for the height equivalent of a theoretical plate was compared with the experimental results. It was showed that the calculated results using the model were consistent with the experimental data. The model may provide the fundamentals for optimizing experimental conditions and scale up.

The mechanism of diffusion of a citric acid aqueous solution upon a sorption resin granule depends upon it structure and dimension of pore and distribution surface energy on sorption granule surface. Especially under the condition of high concentration liquid phase, diffusion in the solid phase usually proceeds as a diffusion controlled zone. Glueckauf and Hill suggested respectively linear driving force (LDF) model and modified linear driving force (MLDF) model. When ratio of liquid and solid phases is rather high and phase equilibrium model is nonlinear, we obtain analytical solution and plots of these models for the sorption and desorption steps.

Vapor - liquid equilibria for mixtures of acetone and poly butyl methacrylate with three different molar masses from 17278 g/mol to 88059 g/mol were obtained at 25. 0℃ by using the Quartz - Spring gravimetric method. The reduced pressure p1/p°1 versus mass fraction W1 plots were found to be independent of the molar mass of the polymer within experimental error. The calculated Flory - Huggins interaction parameters X exhibit a strong concentration dependence. The molar mass of the polymer also exerted a definite influence. The experimental Flory - Huggings interaction parameters were correlated by the revised Freed model.

The vapor liquid equilibrium data for the cyclohexane- 1-butanol- toluene ternary system under pressures from 101. 3 to 911. 9 kPa were predicted by three component Wilson equation from the unified correlations of the corresponding binary systems and compared with the experimental data. Good results were obtained.

Batch adsorption experiments were carried out at 25℃ using activated carbon to adsorb chloroform from water. This system was found to obey the Langmuir isotherm numerically computed bulk concentration time change for the surface diffusion model and that by the pore diffusion model were both in reasonable agreement with the measured data. The effective pore diffusivity was found to be almost independent of the initial chloroform concentration, while the effective surface diffusivity increased with the increase in the initial concentration, Both the resistance of particle - fluid mass transfer and intraparticle mass transfer should be considered for adsorption in liquid.

A rule that assigns a weight to each stream according to two weighting levels is proposed. An efficient tearing algorithm for decomposition of chemical process flowsheets based upon the rule proposed here is developed. A practical example of ketone - benzol dewaxing is examined. The proposed algorithm can find the optimal cut - set for this example. The results are better than former tearing algorithms in convergence behaviour.

The concept of non - equilibrium dissolution in pervaporation is proposed on the basis of the solution -diffusion model of the membrane process. This is a supplement to the studies on pervaporation mechanism. A method for determination of the dissolution rate coefficient is developed and the coefficients of water and ethanol dissolving into the PVA membrane are measured by using this method.