On the basis of the analysis of the modelling of catalyst pellets for catalyst design purposes, several complex problems like activity distribution and multiplicity in catalyst pellets are investigated by using a user-oriented computer program, ESTRECAP. Furthermore, the strategy of directed catalyst pellet design is outlined with two model systems.

Based on the non-linear complex kinetics of enzymatic hydrolysis of cellulose, the static bifurcation behavior of enzymatic hydrolysis of cellulose in CSTR with steady state operation was studied. It was shown that there existed bifurcation structures of the exit concentration in kinetic and operational parameter spaces. The bifurcation and the steady state solution diagrams were obtained.

In this article the non-equilibrium stage model is modified and used for processsimulation of catalytic distillation, which consists of rectifying and stripping sections with conventional structures of a packed column and a reaction section with catalyst bed specially packed, as proposed by CR&L Co. The mass transfer rate in the reaction section is calculated by using gas and liquid film mass transfer coefficients specially measured for this structure of catalyst bed and the mass transfer rates in the rectifying and stripping sections are calculated by using Ondas correlation. The process simulation of synthesis of cellosolve with catalytic distillation is accomplished on the basis of the kinetic equation of reaction between ethanol and ethylene oxide on molecular sieve catalyst NKC-01 and the Newton-Raphson technique The results are satisfactory.

Dropwise condensation of steam under atmospheric pressure was realized on the polyoctafluorocyclobutane (POFCB) film prepared by plasma polymerization technique. The experimental results were compared with previous studies. The fluctuation of temperature on the condensation surface was measured by a HP 3852A Data Acquisition / Control Unit to confirm the difference of dropwise condensation from filmwise condensation.

In this paper a method based on enthalpy intervals of composite curves is presented for area targeting of Heat Exchanger Network in the presence of stream split constraints. The results show that in the case of slightly different fihn heat transfer coefficients the network structure without stream split constraints can reach a good area target, but in the case of significantly different coefficients the network structure with stream split constraints can achieve a better area target by optimally arranging match sequences.

A new experimental device was designed for fouling measurement , and the mechanism of calcium carbonate scaling on a heated surface was thus studied by using simulated hard water . A deposition-free removal mechanism of scaling was proposed and a mathematical model based on turbulent burst theory was derived with the combination of Hassons ionic diffusion model and the rate of scaling predicted with the model agreed well with the experimental data .

A new mixing rule was proposed by combining the hard-sphere three-parameter equation of state and the excess Gibbs energy model. Vapor-liquid equilibria at low and high pressure for 28 strongly polar binary systems and 9 ternary systems were predicted by using binary interaction parameter at low temperature of the group contribution model, such as UNIFAC and modified UNIFAC model. The results show that the new model yields accurate predictions for the phase equilibria of mixtures with a wide range of temperature and pressure.

A modified Huron-Vidal mixing rule is presented by introducing excess Gibbs energy(gE) models into mixing rules for cubic equations of state at a reference pressure. The Soave-Redlich-Kwong equation of state and Wilson model is used as an example by taking atmospheric pressure as reference pressure. VLE data are predicted for 50 sets of 16 typical systems. Examples are also given for high pressure VLE prediction. The results show that the mixing rule enables direct incorporation of parameters of low pressure gE model for predicting low and high pressure VLE with cubic equations of state.

In this paper a high-pressure equilibrium device was developed for measuring the solubility of solids or liquids in supercritical fluids by the static method. The solubility data of solid sulfur in super / near-critical H2S, CO2, CH4 and H2S-rich sour fluid mixtures were measured respectively. Some of the data are published for the first time. The agreement of the experimental results with the data from the literature shows the reliability of the developed device and method.

In this paper the dissolving behavior of solid sulfur in super / near-critical H2S-containing sour fluid mixtures is treated as a supercritical fluid extraction of solids. By modifying the conventional mixing rule, a new thermodynamic model based on PR equation of state for solubility calculations is developed. The new model is used to correlate solubility data of solid sulfur in pure H2S, CO2 and CH4 as well as to predict sulfur solubility in H2S-containing sour fluid mixtures.It is shown that the proposed model is in agreement with the experimental data of this work and those from the literature.

A new equation for calculating surface tension is deduced with group theory and surface thermodynamics of solution The equation is simple in form and conveninent in use, and the parameters have obvious physical meaning. For a very dilute solution the equation can be simplified into σo - σ = αc The experimental data in the literature and empirical equations, such as Szyzkowski equation for the absorptive system of monomolecular film could be interpreted with the proposed equation. Correlation of the data for 235 binary system with this equation shows that this equation is more applicable and reliable.

Partial differential equations are often used to describe distributed parameter systems and are changed into ordinary differential equations during parameter estimation. The possibility of decreasing the dimension of ordinary differential equations by Karhunen-Loeve method is studied. The procedures of the present method are illustrated with the oxidation of carbon monooxide reaction system as an example. The results of simulation show the successfulness of the method.

The kinetics of solvent extraction of Co2+and Ni2+with three typical acidic organophosphorus extractants, di-2-ethylhexyl phosphoric acid(P204), ethylhexyl phosphiric acid mono-2-ethylhexyl ester(P507) and di-2, 2, 4-trimethyl phosphinic acid (Cyanex 272) was compared by using the data determined by the author and from the literatures. The rate of solvent extraction of Co2+was faster than Ni2+. The extraction of nickel was controlled by chemical reaction in the aqueous layer. Cobalt extraction is under a mixed reaction-diffusion regime and its reaction zone is located at the interface and in the aqueous layer, which could be shifted with the change of the reaction conditions. With regard to the reaction, the rate-controlling one might be the exchange of the inner shell coordinate water with the first substituting extractant molecule,which is in agreement with the Eiger-Willkings rule of coordination compound formation in a homogeneous system. The kinetic activity of the extractants depended on the polarity of the phosphonyl group in the molecule of the extractant, and the activity decreased with the substitution of the oxyalkyl groups with the alkyl groups.The polarity of the phosphonyl also predominates over the acidity, surface activity and the dissolution rate of the extractant from the organic phase to the aqueous. In the present research the extraction rates of both Co2+ and Ni2 decreased in the sequence of P204, P507 and Cyanex 272.

The overall plate efficiency of vapor-liquid-liquid three-phase distillation was investigated in a sieve-tray Oldershaw distillation column of 50mm diameter . In froth flowregime , the effects on mass transfer of the operating conditions , e.g. vapor velocity and liquid to vapor loading ratio , and the physical properties of liquid phase , including surface tension , interfacial tension , dispersion viscosity , density , diffusion coefficient , relative volatility etc. , were systematically studied . The influence of the oil to water volume ratio on overall efficiency was also investigaed . Three-phase and two-phase distillation operations were compared in terms of plate efficiency . An analysis of the experimental results showed that the overall efficiency for three-phase distillation was lower than that for two-p hase distillation and interfacial tension and dispersion viscosity are the main influence factors . Finally , a correlation equation of overall efficiency for vapor-liquid-liquid three-pha se distillation in froth regime was obtained by regression of experimental data . This empirical correlation may be of some value in design and optimization .

The preparation and characterization of the affinity-ligand-modified liposomes were studied. The optimum conditions for liposome preparation and the ligand-modifying reactions were determined. Using p-aminobenzamidine (PAB) as an affinity ligand, the trypsin inhibition kinetics by PAB-modified liposomes and the characteristics of affinity ultrafiltration of trypsin were investigated. The results showed that the equilibrium binding constant of the PAB-modified liposomes for trypsin was more than 1/4 of that of free PAB for trypsin and the affinity-ligand-modified liposomes were effective in affinity separation for trypsin.

A computational study of laminar flow and heat transfer to highly viscous pseudoplastic fluids in vertical pipes under constant heat flux is presented. Experimental local heat transfer coefficients are compared with the predictions by computer simulation based on the equations of continuity, momentum and energy. The numerical predictions fit the experimental data excellently. The results show that the difference in radial temperature is very large in heat transfer to highly viscous fluids. It is demonstrated that in order to minimize the difference in radial temperature and wall temperature it is necessary to use a smaller pipe diameter, which is an effective measure to solve the problem.

Sixty one vapor pressure data of CH3CF3 above 230K have been measured with a precision of |ΔT≤ 28mK, |Δp|≤ 1.4kPa, which showed, obvious deviation from references. The critical parameters were determined as ρc = 442± 4kg/ m3, TC = 346.16 ± 0.05K and pc = 3.781± 0.006MPa by observing the disappearance of vapor-liquid meniscus and the critical opalescence. The normal boiling point was predicted as Tb = 225.69K.

A generalized mass transfer model describing hemodialysis, hemoflltration andhemodiafiltration is proposed and solved in this paper. The effects of various parameters on mass transfer characteristics are analysed. Experimental results in vitro are proven to coincide with theory. The maximum relative error is less than 10%.