With large increases in natural gas reserves proven worldwide, it can be expected that natural gas will play an increasingly important role in energy and chemicals supplies in the 21st century. Methane is used as a fuel for industrial and residential heating, However, much more methane is produced than is required for this purpose and it may be commercially advantageous to convert methane into industrial chemicals. Selective activation of C-H bonds has been the goal of researchers in heterogeneous and homogenous catalysis for over 50 years. Selective reaction of saturated hydrocarbons like methane is difficult due to the similar high dissociation energy of activation. Plasma chemical processing is a promising route for synthesis of chemicals that have high activation energies, because very high energy can be supplied to the plasma and many kinds of reactive particles, electrons, free radicals, ions metastable species and photons, are produced in a plasma chemical processing system. This paper reviews the general situation on the thermal plasma decomposition of methane into acetylene,cold plasma catalytic conversion of methane into C 2, methanol and formaldehyde etc. The cold plasma utilized natural gas chemical engineering is discussed from process, reactor, concerted catalysis, reaction mechanisms and reaction dynamics in detail. However, the elucidation of the reaction mechanisms of reactions in the plasma is largely impeded due to the complex nature. Among all of the plasma generated species, free species are believed to be most important for chemical reactions. Extensive research has to be done in order to reasonably understand the elementary reactions.

A novel kind of preparative electrochromatography, namely hydroxylapatite electrochromatography (HEC), is proposed in which an electric potential is applied to the compartment packed with hydroxylapatite. In the present study, the effects of electric migration,including the electrophoresis of protein and the electroosmosis of solvent,on the separation performance of HEC are experimentally investigated. Electroosmotic fluxes of membrane, membrane and packed medium are determined and the driving forces by electoosmotic flux of membrane and packed medium are interpreted, respectively. An increase in electroosmotic flux is obtained in response to the increase in electric field strength and the decrease in ionic concentration of the buffer. The breakthrough curves obtained in the presence of an electric field show an enhanced adsorption of BSA on hydroxylapatite in terms of available bed volume for adsorption and dynamic adsorption capacity. When the elution of BSA from hydroxylapatite is conducted with the buffer of high salt concentration, the enhancement of mass transfer is mainly contributed by electrophoresis. In this case the suitable selection of polarity of electric field is essential to resolution. When elution is done with the buffer of low salt concentration, the contribution of electroosmotic flux to mass transfer becomes significant. The above results show that the application of electric field to hydroxylapatite chromatography, as shown by HEC, greatly improves its separation throughput and efficiency.

The third-stage multicyclone separator is widely used in FCC unit. To improve the performance of cyclone tube, a new type of PDC series was developed. The flow field, especially in the dust hopper, is measured by using five-hole probe. This measurements give the 3D velocities and pressure distribution. It was found that there exists "Swirl Shield Action"(SSA) near the discharge port in the dust hopper. It can reduce the reentrainment in the hopper, and result in higher performance of cyclone tube. It was also found that both the structure and operation parameters could affect SSA. Keeping a suitable draw-off gas ratio, optimizing the structural parameters of guide vane and providing an anti-entrainment hole on the double cone are helpful to forming SSA in the dust hopper.

A full form of the improved algebraic Reynolds stress model(ASM)is employed to simulate swirling turbulent flows in a swirl combustor with two coaxial jets in this paper.The calculated results are compared with the measured test data and those predicted by the k-ε model and a simplified form of the improved ASM.It is shows that better predictions are achieved by the full form of the improved ASM,which are closer to the measured data than those obtained by the other two models.

Radial slip velocity and solid velocity are formulated by using the energy-minimization multi-scale (EMMS) model, leading to analytical solutions for radial distribution of voidage, fluid velocity, cluster diameter and particle mass flux, and indicating the existence of radial heterogeneity and annulus/core structure. Model calculation is well consistent with experimental data. The model overcomes the difficulty in solving the original EMMS model, and makes it possible to predict patterns in gas-solid two-phase systems without using adjustable parameters.

Two kinds of activated carbon fibers (ACF) made from polyacrylonitrile were selected in order to study their NO reduction properties. Experimental results showed that the NO reduction activity of HNO ₃ dipped ACF is higher than that of non-treated one. In order to know the adsorption properties of various oxygen containing gases on ACFs, TPD experiments over ACF showed that the adsorption abilities of CO, NO and O ₂ on HNO ₃ dipped ACFs are higher than that on non-dipped ACFs, but CO ₂ has a reverse result. According to literature and experimental results, we suppose that dissociative adsorption of NO on ACF is the rate controlling step of this reaction, and the primary product of this reaction is carbon dioxide.On the basis of this assumption, a first order kinetic equation was used to treat experimental data, and Arrhenius equations for NO reduction over four different ACFs were obtained.NO reduction activity of HNO ₃ dipped ACF was always higher than that of non-dipped one.

The Hansen solubility parameters of ethylene/vinyl aceate copolymer materials and toulene/ethanol mixtures were calculated through the group contribution method. The interaction properties and mutual solubility between polymer and mixtures were analysed,based on the difference of two- or three-dimensional component of solubility parameters. To compare the results of swelling experiment of EVA14 and EVA28, the estimated values were in agreement with experimental data. The membrane was prepared with EVA28 and used for separating toluenl/ethanol mixture, the results show that the membrane was preferential for permeation of toulene. As the mass fraction of toluene was 2%-35% at 25 ℃ in the feed, the toluene flux increased from 55 g·(m ²·h) ^-1 to 900 g·(m ²·h) ^-1 ,and the separation factor decreased from 18 to 4. The results also show that the selectivity and the flux are related to the temperture of the feed. The quasi-equilibrium criteria of pervaporation were compared with VLE of the toluene/ethanol mixture.

Some important peculiarities of interfacial mass transfer with chemical reactions in liquid-liquid systems were explained with the help of interfacial dispersed zones (IDZ) formation.A sudden and sharp increase in HCl extraction rate by tri( n -dodecyl)amine was explained by means of a new dispersed phase formation inside of the organic layers adjacent to the interphase.This process of water mirodroplets formation is accompanied with the change of local equilibrium constant and concentration gradient.Surface-active substances(SAS) added to the system could essentially affect the rate of interfacial diffusion because of change of number and dimension of microparticles inside of IDZ.The rate of interfacial diffusion increases if SAS stabilize IDZ and (or) enhance adsorption of reactants on the surface of microparticles of IDZ.The opposite situation can be observed if SAS destabilize IDZ and (or) decrease adsorption of reactants.These effects were found in extraction and stripping of Cu ²⁺ in the system with 2-hydroxi-5-octylbezo phenonoxime.

By means of structure and process decomposition, this work is devoted to elucidating mass transfer process in heterogeneous flow theoretically.Mass transfer process in heterogeneous flow of gas-solid circulating fluidized bed is considered to consist of two subprocesses: static and dynamic.At the mean time,the static subprocess is decomposed to three scales: mass transfer in dilute phase; dense phase; and inter phase.Then, by virtue of EMMS model,local hydrodynamics of heterogeneous two-phase parameters are calculated from the condition of operation parameters (solids mass flux, gas velocity) and species characteristics.Mass transfer coefficient is obtained by slip velocity ,voidage, ect.Based on above,axial distribution of concentration is studied.At last, effective mass transfer coefficient of circulating fluidized bed is discussed.

The mathematical model of complex countercurrent multi-effect evaporation with condensed water flash is established, which aims at minimum annual cost (including cost of fresh vapor, vacuum pump power, evaporator, maintenance and depreciation).Based on such decisive variables as the pressure of fresh vapor, the pressure of condenser and heat-transfer mean temperature difference of vari-effect,the model is solved by the complex method,Lagrangian multiplier method, iteration method and matrix method.The practical example indicates that the influence of the pressure of fresh vapor, the pressure of condenser and flash of condensed water on the optimum design results is notable.The annual cost calculated by the optimum method is decreased by about 11% against that calculated by the conventional method.The new algorithm increases the convergence speed and stability.

In this paper, the pervoskite-related ZrO₂-doped SrCo_0.4 Fe_0.6 O_3-δ dense membrane reactors for methane partial oxidation to syngas are studied.Two membrane reactors with or without catalyst, which are running for a long time,are investigated.The results indicate that the membrane can continuously operate for over 300 hours in a reducing environment.Oxygen-permeation performance of membranes for three experimental processes including oxygen-permeation experiment are compared.The oxygen permeation flux increases in the order of oxygen-permeation experiment, blank membrane reaction experiment and membrane reaction experiment.The effects of feed conditions on experimental results in membrane reactor show that the feed concentration of methane influences the oxygen permeation flux of SCFZ membrane.The structures and compositions of membrane are also characterized by X-ray diffraction, scanning microscopy and energy dispersive spectroscopy.

The effects of extraction time,alkaline concentration,and the addition of cartilage on the extraction of mucopolysaccharides from shark fin cartilage digested with NaOH were investigated.The main components of mucopolysaccharides during the degrading process were analyzed by cellulose polyacetate strip electrophoresis and agarose gel electrophoresis.The results showed that the extraction of mucopolysaccharides was increased with the increase of extraction time,alkaline concentration and the addition of cartilage.According to the different electrophoretic migrations,the preparative mucopolysaccharides composed of different polysaccharides with electronegativity can be divided into two parts,the chondroitin sulfate with higher migration and the other with lower migration.The lower part is unstable and easily degraded with alkaline solution.

A new process was developed for synthesis of acrylated alkyd resin in which a methyl methacrylate (MMA) is copolymerized with a maleinized alkyd resin.The effect of the concentration of MMA and initiator, addition methods on the film properties has been investigated.It was showed, compared with the conventional modified alkyd resin, the MMA modified alkyd resin made by the new process is superior in appearance of film, impact resistance and resistance to petrol.The new process broadens the materials source of modified alkyds, reduces the cost of product.The satisfactory formulations are obtained with 30%-40% of methyl methacrylate, 3.0% of initiator and 60%-70% maleinized alkyd resin.The key technique in this process is the addition method, which MMA and based alkyd are added into reactor together, and initiator is introduced into the reacted mixture gradually in four hours.

Solubility of α -asarone in supercritical carbon dioxide was measured and calculated by P-R equation and Chrastil method. Compared with experimental data, the average relative deviation of the calculated solubility of α -asarone is 25% and 8% for P-R equation and Chrastil method respectively,which indicates that the experimental results can be correlated well with Chrastil method.The Chrastil equation for the solubility of α -asarone in supercritical carbon dioxide was subsequently given, which can be applied to the prediction of solubility according to the practical supercritical conditions.

Electromotive force measurements of the cell, Na-ISE|polyelectrolyte( m_p(mono) ),NaCl( m_a)|AgCl,Ag,are carried out at the different molalities of NaCl in aqueous poly(diallydimethylammonium chloride)(PDADMAC)and poly(anetholesulfonic acid, sodium salt)(PAS) solutions at 308.15 K. The mean activity coefficients of NaCl in aqueous polyelectrolyte solutions are determined by using the standard cell potential which are obtained from the measurements of the electromotive force of cell,Na-ISE| NaCl( m )|AgCl, Ag, combining with the Pitzer model for electrolyte solution.At different concentrations of PDADMAC solution, the mean activity coefficients of NaCl decrease monotonically as the concentrations of NaCl increase.However, for the aqueous solutions of PAS, there is a maximum value as the concentrations of NaCl increase.

The liquid-liquid equilibrium data for two binary systems,CH₃CN-H₂O-KF and CH₃CN- H₂O- K₂CO₃ are determined at 25℃.The correlated results of the liquid-liquid equilibrium data are carried out by using Pitzer theory and NRTL equation.The correlated and experimental results are in good agreement.The basic data for separating acetonitrile-water system using salts in industry are provided.

With Pt as anode, saturated calomel electrode as reference electrode,the effects of different electrolytic cells, electrolytic solvents, supported electrolytes and cathode materials on electrochemical hydrogenation of lignin were studied.The results showed that electrolytic hydrogenation of lignin was better in the electrolytic system of DMF+EtOH+H₂O+Bu 4NBr with sponge Pb as cathode in the divided electrolytic cell than in the other selected electrolytic systems in terms of ultimate analysis and soft point of hydrogenated lignin.After electrolysis, the hydrogen content and the atomic ratio of hydrogen to carbon of hydrogenated lignin can increase by 0.81 and 0.02 respectively, but the soft point of hydrogenated lignin can decrease by 9℃. At the same time, current dependence of potential indicated that electrolytic hydrogenation of lignin can be carried out in this electrolytic system.

The A-type zeolite membrane was synthesized on a porous TiO₂ support by using dip-coating and microwave heating.The influence of chemical composition of precursor on the formation of zeolite membrane was investigated.The results showed that the concentration of the precursor determines the performance of zeolite membrane.The zeolite A crystals and the surface morphology of membrane were characterized by XRD and SEM.For the zeolite membrane,the particle size on its surface and the thickness of top-layer was about 0.5μm and 1μm,respectively.The permeability of H₂ and N₂ hardly changed with pressure and its permselectivity of H₂ to N₂ was about 5,more than that of Knudsen diffusion.It suggested that the zeolite A membrane exhibits partial molecular sieving.According to pervaporation measurements by using H₂O/EtOH mixture,the flux and selectivity of the A-type zeolite membrane for 5% H₂O/95% EtOH(mass) mixture at 323K was 0.335kg·m^-2 ·h^-1 and 690,respectively.