The applications of aqueous two-phase extraction in concentration and separation of various kinds of antibiotics are discussed,with good results for the separation and purification of erythromycin and penicillin G.The given technology not only can be used in the separation of biological macromolecules,but also can concentrate the broth containing small solutes of biomolecules.The progress in the thermodynamic models and study on mass transfer for aqueous two-phase systems are also presented.The integration of biochemistry, pharmaceutical chemistry, chemical technology and chemical engineering is required to increase the scientific content of traditional antibiotic production,and is also the important path for solving practical commercial problems.When the products are fully water-soluble, such as antibiotics, sugars, glycopeptides, etc, the synthesis has to be carried out in aqueous medium.In this case the use of aqueous two-phase systems could be a suitable option for continuous extraction of the products.A new approach, the combination of aqueous two-phase systems and enzymes that are covalently immobilized inside the porous structure of a support,is used in the kinetically controlled synthesis of cephalolexin.The characteristics of this new approach are explained in detail and the experimental method is also discussed.A comparison of results of the biphasic synthesis with monophasic synthesis is given.In the biphasic synthesis the degree of hydrolysis of cephalolexin decreases significantly, and its yield increases effectively.

An apparent kinetic model for lysozyme refolding was established,and the refolding behavior of denatured lysozyme facilitated by the molecular chaperone GroEL was studied.The effects of denatured lysozyme concentration, adenosine triphosphate (ATP) concentration, and the molar ratio of GroEL to lysozyme on the refolding yield and the refolding rate constant were investigated.The lysozyme concentration showed more significant effect on the refolding rate constant than on the refolding yield.Both refolding yield and refolding rate constant increased with increasing ATP concentration.At a definite protein concentration, optimal concentrations of both GroEL and ATP existed to give maximum refolding yield and refolding rate constant.

Unsteady-state performance of a fixed bed reactor for methanol synthesis,operating under flow reversal mode, was experimentally studied.The effects of various factors, such as feed gas velocity, feed composition and cycle duration on the transient axial temperature profile in the bed,propagation velocity of thermal wave,transient composition of tail gas and time-averaged methanol output were investigated at a pressure of 2.0 MPa,gas velocity about 0.20-0.50m·s ^-1 ,cycle duration of 20-120?min and total concentration of carbon oxides,∑CO _x ,0.33?%-7.32%mol.Higher conversion of ∑CO _x than that of steady-state operation was achieved even though for a very low concentration of ∑CO _x down to 0.33%mol.

There are many methods for preparing ultrafine powder.For the reason of experimental condition and cost, it is difficult to scale-up.The reverse-micelle method overcomes these shortcomings, but because micromixing can not be obtained when oil is mixed with water, the result of scaling-up is unsatisfactory.In this paper,the spraying and rotating mixer is used to mix two phases quickly and uniformly, and a better product can be obtained.A mathematical model is used to deduce the result of mass transfer between two phases at different impeller speed and different phase ratio, then experimental result is used to test the exactness of the model.The model can be used for the research of scaling-up of this method.

The development of the A301 based on Fe 1-x O ammonia synthesis catalyst has for the first time allowed ammonia to be made economically at pressure close to those of gas production.The high activity and long life of the catalyst has been proved over a period of nine years in hundreds of 150-500t/d scale converter charges.In this paper,the activity test of A301 catalyst for use at low pressure was carried out in a equipment,called"sidestream"reactor,in which the catalyst was present as a packed bed of commercial-sized material and was subjected to 1000t/d scale plant conditions.The main results of the use of the sidestream reactor for the testing of catalysts are as follows:the outlet ammonia concentrations of the sidestream reactor under plant conditions are 14.35%-16.55%,15.24%-16.66% and 17.2%-18.8% by volume at 7.0,8.5 and 10.0MPa of pressure respectively.A301 is the most active of all iron catalysts tested for low pressure and low temperature operation and is the only catalyst that has been demonstrated to work efficiently at pressures in the region of 7-10MPa.

The dynamic on-line monitoring system (DMS) based on on-line training of ANN has been implemented successfully in a refinery for real-time,on-line and dynamic estimation of quality indexes of fractionator side draw,such as end point of raw-gasoline,pour point of diesel-oil,Reid vapor pressure,flash point,freezing point.It improves the control performance and optimizes the operation of the fractionator.To improve the predicted accuracy of DMS and fit the new production cases,a novel ANN training method, on-line training method,has been proposed in this article.This method overcomes the disadvantages of off-line training of ANN effectively.It can save lots of time and effort in contrast to the conventional off-line training of ANN.It improves the performance of DMS.This method includes three main steps:judge when ANN needs to be trained again;get new training patterns on-line;train ANN on-line.Steady state determination of the process is a key procedure in on-line training.A method based on the mathematical theory of evidence is used in steady state determination.This improves the training results of ANN and the reliability of DMS.

Statistical associating fluid theory (SAFT) is modified with two improvements.One improvement is the consideration of the segment shape of chain molecules in the reference term with the Hard Convex Body equation of state.The other is the change of dispersion term because of the chain formation.The first improvement makes better expression of critical points for small non-sphere molecules and the second for chain molecules.With these two modifications,the theoretical critical compressibility factor of the extended SAFT is in the range of 0.23-0.31,that is the same as those of such real nonpolar fluids as alkanes.The extended SAFT is used to correlate and predict saturated pressures and saturated liquid densities with the average relative deviations less than 1% for most of n -alkanes and branched alkanes.Meanwhile the predicted critical temperatures,pressures and densities are in good agreement with experimental ones.This equation of state can be used in thermodynamic calculation for systems with components in the critical region.

Thermal conductivites at 30℃ and atmospheric pressure for 20 binary mixtures of 10 kinds of alcohols, methanol, ethanol, n -propanol, iso -propanol, n -butanol, iso -butanol, sec -butanol, tert -butanol, n -pentanol and iso -pentanol,with 1,2-dichloroethane and with cyclohexanone, respectively, were measured by transient hot wire method with the uncertainty of less than ±0.7%.Five different thermal conductivity predictive equations from literatures were used to calculate the thermal conductivities of these liquid mixtures investigated.The calculated values are compared with the experimental data from this work and the results were discussed.

A dynamic modeling method for large scale circulating fluidized bed boiler is presented in this paper.Cell approach is used to simulate the axial distributions of solid and gas phase in the bed,and ’core-annular’ construction is used to describe the radial distributions of solid particles and particle cluster.Meanwhile,it takes into account the influence of wide size distribution of both bed and feed materials on hydrodynamics,chemical reactions and heat transfer.Integration of CFB loop,steam-water and air/gas system model for circulationg fluidized bed boiler and a partitioning and multi-rate integration technique for solving the integrated model is as also presented in the paper.Based on the method,simulations of static and dynamic performance for 410t·h ^-1 Pyroflow CFB boiler is carried out.The results show that the model is capable of predicting the overall performance of CFB boiler.The modeling method has theoretical and engineering significance for the research of combustion technology,large scale boiler design and operating performances of circulating fluidized bed boiler.

The relationships of particle axial distribution in the bubble column slurry reactor for the synthesis of methanol with various parameters, such as superficial gas velocity, reactor diameter and catalyst concentration, were discussed by means of a mathematical model verified by model test.The influence of the main construction parameters of the reactor and the operating parameters of industrial demonstration unit of 10000t·a ^-1 were determined.The modeling results obtained under the conditions of two industrial synthesis gases showed that the influence of pressure in three-phase methanol synthesis process was most obvious, and slurry bed height was also a more important adjustable parameter.Under the operating condition in this paper, as methanol yield reaches 10000 tons per year, outlet methanol mole fractions is in the range from 0.07 to 0.10 and CO conversion is in the range from 40% to 50% within wider ranges of pressure and temperature with recycle and once-through of synthesis gases.

The effect of reaction conditions on the gross heat efficiency were studied on the basis of mass,and energy, balance as well as the kinetics of POX in the on-board hydrogen generation process, and the suitable reaction conditions were optimized when the whole system was considered as an autothermal process. In order to get η as high as possible, the mol ratios of O ₂/CH ₃OH ( f ) and H ₂O/CH ₃OH ( n ) should be adjusted carefully, and the suitable f and n were ca. 0.35 and ca. 0.8 respectively. The effect of reaction pressure on η was relatively trivial, which made it possible for POX to take place at a relatively high pressure to meet with PEMFC which usually works at 0.3 - 0.5 MPa. The heat exchange efficiency between the reformate and the cool reactants in the evaporator should be enhanced by increasing the heat exchange areas in order to obtain higher heat efficiency. Although fairly good heat efficiency could still be obtained when more methanol was consumed to meet with the increase of loading of PEMFC, more oxygen would have to be provided to the whole system which made the ’hot spot’ temperature even worse.

The effect of reactor configuration and technical parameters on the gross heat efficiency and "hot spot" temperature was investigated in an autothermal operation process of methanol partial oxidation based on the balance of mass and energy balance as well as kinetics of the reactor. The conversion of methanol, productivity of hydrogen and the gross heat efficiency increased with the decrease of height/diameter ratio of the reactor when the same amount of catalyst was used, so the catalyst effective index was enhanced by this means. Furthermore,for the same gross heat efficiency,a lower amount of oxygen or air was needed when the height/diameter ratio was relatively small, which lead to the decrease of "hot spot" temperature. In order to make the "hot spot" temperature even lower, a reactor with multi-inlets could be used.The "hot spot" temperature dropped greatly when oxygen was input by two inlets or more,and only trivial loss of conversion and hydrogen productivity was observed. Therefore, the principle of reactor design was obtained, and the suitable configuration of the reactor, such as radial flow reactor and inorganic reactor was proposed.

Emulsions composed of nitrobenzene/water/sodium dodecyl sulfate (SDS) were prepared at different compositions.Specific conductivities in the oil-rich phase of emulsions were measured at different times in presence and without presence of hexanol.In order to find the relationship between stability and specific conductivities of emulsions, a new concept of a incremental ratio of specific conductivity ( κ _r) and a dynamic model of creaming process were proposed.Stability of emulsion was discussed by employing the relationship of the incremental ratio of specific conductivity with time and the dynamic parameters of creaming process.The results show that the stability of emulsion decreased with the increase of the incremental ratio of specific conductivity.In addition,the values of the changing ratio κ r with time, d κ r/d t ,at different times were calculated and the maximum values of d κ r/d t were obtained by using the plots of d κ _r/d t against time.The values of (d κ _r/d t ) _max and corresponding t max were also used to discuss the stability of emulsion.

In this work,the effect of alcohols (including alcohols containing single, two, three hydroxyl groups, respectively) on the enzyme- catalyzed synthesis of Z-L-Asp-PheOMe (ZAPM) is investigated by using a new technique of enzymatic catalysis in a heterogeneous pseudo-eutectic solid-to-solid mixture with thermolysin.The experimental result shows that the alcohols containing two hydroxyl groups are the most suitable adjuncts for the studied enzymatic synthesis system, and the yield of ZAPM for 1,4-butanediol as an adjunct reaches 95% at reaction time 2h, which is better than the results in two-phase systems and other pseudo-eutectic solid-to-solid mixture reported in literature.

In this work, a new idea for separating or purifying hydrogen from gas mixture was proposed. As the hydrate formation pressures for different gas components at the same temperature are different from each other, the gas mixture can be separated partially by forming hydrate. This technology is especially suitable for purifying hydrogen, as hydrogen can not form hydrate while other components can. Schematics for purifying hydrogen by forming hydrate were given. A series of fundamental experiments were performed,which showed that it is a promising technology to separate or purify hydrogen by forming hydrate.

The synthesis process of a biomimetic membrane directed by macromolecule(CTAB) assemblies was researched by using hydrolysis reaction of tetraethylorthosilicate. Influences of CTAB assembly configuration,pH values,initial concentrations of CTAB were investigated on the biomimetic membrane through characterizing techniques such as SEM and TEM.Integral and resilient freestanding membranes were synthesized under the optimized biomimetic operation conditions. These research results are essential to synthesise of high performance separation membranes through biomimetic methods.

Alumina film with nano-pore array structure was prepared by anodic oxidation of aluminum matrix with different techniques treated in phosphoric acid solution.It was indicated that aluminum matrix with different composition had a great effect on the formation process and nano-pore array structure of alummina film.It was found out that the basic cause of such effect was the difference of the crystal defect density of aluminum matrix.