The bench-scale cooling crystallization for ternary solution of L-ascorbic acid (Vitamin C)
was studied. The solid-liquid phase diagram of Vitamin C-water-ethanol system was obtained
on the basis of differential scanning calorimeter (DSC) curves. The heat of crystallization
of Vitamin C was calculated with the aid of quantitative analysis. According to the
population balance equation under unsteady state, the rates of nucleation and growth were
determined. The parameters of crystallization kinetics equations were estimated by
regression of experimental data. Crystal morphology and size were determined with x-ray
diffraction and TA Ⅱ Coulter Counter.

The influence of the third component on gas-liquid mass transfer was studied by use of
laser holographic interferometry. Four surfactants were added respectively and experimental
results show that the microamount of surfactants can change obviously the concentration
near the interface on bubble mass transfer process, which indicated that the third
component has a significant effect on the bubble mass transfer process.

Predispersed solvent extraction (PDSE) is a new method for separating solutes from aqueous
solution by solvent extraction and one which has shown promise for extraction from
extremely dilute solution very efficient and very quick. The use of colloidal liquid
aphrons in predispersed solvent extraction may ameliorate the problems such as emulsion
formation, reduction of interfacial mass transfer and low interfacial mass transfer areas
in solvent extraction process. In present paper, colloidal liquid aphrons are successfully
generated using kerosene as a solvent, tributyl phosphate(TBP) as an extractant, sodium
dodecyl benzene sulphate(SDBS) as surfactant in aqueous phase and Tween-80 in oil phase.
Extraction of phenol from dilute solution was studied by using colloidal liquid aphrons and
colloidal gas aphrons in a semi-batch extraction column. It has been found that the PDSE
process is more suitable for extraction of dilute solutions. It has also been discovered
that the PDSE process has a great advantage over traditional single-stage extraction
process.

Oil-in-water(o/w) emulsions were produced with a membrane emulsification system. The effect
of the continuous phase viscosity on the emulsification was studied. The theoretical
analyses show that the continuous phase viscoeity influences not only the flow field of the
continuous phase but also the interfacial tension. The droplet size distribution and
disperse phase flux for different continuous phase viscosity were investigated
experimentally at constant wall shear stress and constant volume flow rate of the
continuous phase respectively.

The transition from froth to spray regime on sieve trays was experimentally studied in an
air/water simulator with 300mm diameter. It has been found that the regime transition
occurs as the clear liquid height is equal to the residual pressure drop on the trays. A
convenient and accurate technique was proposed for determination of the regime transition
point. Based on analysis of the transition process at a sieve hole, a new formula which can
be used to correlate the experimental results was provided.

Based on the experiments on freeze-drying carrot and potato slabs, the effects of some
parameters, such as heating temperature and pressure on the freeze-drying process are
examined. A simple model of freeze-drying is established to predict drying time and the
mass variations of materials during the drying. The experimental results agree well with
those calculated by the model.

This paper reports on the adsorption characteristic of heavy metal ions (Ni2+and Fe3+)
using a novel biceorbent, prepared from cell walls of Rhizopus oryzae. The optimum
operating conditions are investigated in both single ion system and binary system.

In this work, an Eulerian/Lagrangian approach has been employed to investigate numerically
the flow characteristics, heat transfer and combustion in a tangentially fired furnace. The
RNG (Re-normalization group) k-e model and a new method for cell face velocity
interpolation based on a non-staggered grid system are employed. To avoid pseudo-diffusion
that is significant in modeling tangentially fired furnaces, attempts are made at improving
the differential volume scheme. Some new developments on turbulent diffusion of particles
are also taken into account. Thus, computational accuracy is improved substantially.

It is found analytically that the parabolic radial profile of liquid velocity in
cylindrical liquid-solid fiuidized bed (LSFB) causes particles to circulate around some
radial position. This is the main reason for liquid phase axial dispersions. The liquid-
phase axial dispersion is depressed as the liquid velocity presents a flatter Bessel radial
profile in a converging taper LSFB. The void fraction increases with axial distance in
converging taper LSFB. The behavior produces less liquid-phase axial dispersion.
Experimental results show good coincidence.

This work described the application of wet air oxidation (WAO) to the treatment of desizing
wastewater from natural fiber processing. A two-liter autoclave batch reactor was used for
the experiments. The range of operating temperature examined was between 150 and 290℃, and
partial pressure of oxygen ranged from 0.375 to 2.25 MPa standardized at 25℃. Variations
in Chemical Oxygen Demand(COD) and Total Organic Carbon(TOC) were monitored during each
experiment and used to assess the performance of the process. Experimental results showed
that WAO can be an efficient method for the treatment of desizing wnstewater. Furthermore,
Catalytic Wet Air Oxidation (CWAO) was applied to reduce the reaction temperature and
pressure in WAO process. A higher COD removal ratio was achieved under more mild reaction
condition with the aid of CWAO. A mathematical model was also proposed to simulate the WAO
process of desizing wastewater, in which three distinct kinetics steps were considered to
describe the degradation of starch. The model simulations were in well agreement with the
experimental data.

The diffusion coefficients** ofl-lysine hydrochloride andl-arginine hydrochloride in their
aqueous solu- tions at 25℃ were determined by the metallic diaphragm cell method which is
characterized by accuracy, promptness and convenience. Meanwhile, the densities and
viscosities of the solutions were also determined. Based on all these data a semi-empirical
model for correlating the diffusion coefficients of solid organic salts in their aqueous
solutions at 25℃ was proposed. The fitting result of this model is comparatively
satisfactory. Compared to a former model, Gordon Model, this model can avoid a number of
difficulties and arduous work.

An interfacial equation of state based on perturbation theory for surfactant-oil-water
system has been developed. By combining the interfacial equation of state with Boudh-Hir
and Mansoori’s model, a molecular ther- modynamic model has been proposed. The interfacial
tension of surfactant-oil-water systems can be calculated from the surface tensions of pure
oil and water by this model. The inteffacial tension data for sodium dodecyl sulphate-
heptane-water system, polyoxyethylene n-octylphenol-heptane-water system and hexadecyl
trimethyl ammonium bromide-heptane-water system have been correlated. By using the
adjustable parameters obtained, the interfacial tensions of these systems at other
temperatures have been predicted. Both the correlated and the predicted values are
satisfactory.