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SCI和EI收录∣中国化工学会会刊
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Table of Content
28 January 2009, Volume 17 Issue 1
    PERSPECTIVES
    Modeling and Optimization for Scheduling of Chemical Batch Processes
    QIAN Yu, PAN Ming, HUANG Yacai
    2009, 17(1):  1-7. 
    Abstract ( )   PDF (142KB) ( )  
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    Chemical batch processes have become significant in chemical manufacturing.In these processes, large numbers of chemical products are produced to satisfy human demands in daily life.Recently, economy globalization has resulted in growing worldwide competitions in traditional chemical process industry.In order to keep competitive in the global marketplace, each company must optimize its production management and set up a reactive system for market fluctuation.Scheduling is the core of production management in chemical processes.The goal of this paper is to review the recent developments in this challenging area.Classifications of batch scheduling problems and optimization methods are introduced.A comparison of six typical models is shown in a general benchmark example from the literature.Finally, challenges and applications in future research are discussed.
    FLUID FLOW AND TRANSPORT PHENOMENA
    Simulation of Droplet-gas Flow in the Effervescent Atomization Spray with an Impinging Plate
    QIAN Lijuan, LIN Jianzhong, and XIONG Hongbing
    2009, 17(1):  8-19. 
    Abstract ( )   PDF (619KB) ( )  
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    A comprehensive three-dimensional model of droplet-gas flow was presented to study the evolution of spray in the effervescent atomization spray with an impinging plate.For gas phase, the N-S equation with the k-ε turbulence model was solved, considering two-way coupling interaction between droplets and gas phase.Dispersed droplet phase is modeled as Lagrangian entities, accounting for the physics of droplet generation from primary and secondary breakup, droplet collision and coalescence, droplet momentum and heat transfer.The mean size and statistical distribution of atomized droplets at various nozzle-to-plate distances were calculated.Some simulation results were compared well with experimental data.The results show that the existence of the impinging plate has a pronounced influence on the droplet mean size, size distribution and the droplet spatial distribution.The air-to-liquid ratio has obvious effects on the droplet size and distribution.
    Cryogenic Liquid Slug and Taylor Bubble Length Distributions in an Inclined Tube
    WANG Shuhua, ZHANG Hua, WANG Jing
    2009, 17(1):  20-26. 
    Abstract ( )   PDF (746KB) ( )  
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    An experimental study was carried out to understand the phenomena of the boiling flow of liquid nitrogen in an inclined tube with closed bottom by using a high speed motion analyzer.The experimental tube is 0.018 m ID and 1.0 m in length.The range of the inclination angle is 45°-90° from the horizontal.The experiment focused on the effect of the inclination angle show that the mean liquid slug length and Taylor bubble length increase with the increasing x/D at various inclination angles.At the same x/D, the mean liquid slug length and Taylor bubble length increase first, and then decrease with decreasing inclination angles, with the maximum at 60°.In the vertical tube, standard deviation of the nitrogen Taylor bubble length increase with the increasing x/D.For the inclined tube, standard deviation of the nitrogen Taylor bubble length increases first, and then decreases with the increasing x/D.Standard deviation of the liquid slug length increases with increasing x/D for all inclination angles.
    SEPARATION SCIENCE AND ENGINEERING
    Simulation of 1, 3-Butadiene Production Process by Dimethylfomamide Extractive Distillation
    YANG Xiaojian, YIN Xuan, OUYANG Pingkai
    2009, 17(1):  27-35. 
    Abstract ( )   PDF (388KB) ( )  
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    Nowadays, extractive distillation is the main technique to produce 1, 3-butadiene.This study simulated the 1, 3-butadiene production process with DMF extractive distillation by Aspen Plus.The solvent ratio is the most important parameter to the extractive distillation process.The article has given out the proper solvent ratios, reflux ratios, distillate ratios, and bottom product ratios of the columns.It also discusses the thermal loads of several columns.The results of simulation are consequently compared with the plant data, which shows good accordance with each other.
    The Effect of Hydrophobic Modification of Zeolites on CO2 Absorption Enhancement
    LU Sumin, MA Youguang, ZHU Chunying, SHEN Shuhua, HE Qing
    2009, 17(1):  36-41. 
    Abstract ( )   PDF (139KB) ( )  
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    Two methods of the modification of zeolite were employed:framework element modification and surface coating, and the influence of the zeolites before and after modification on the CO2 absorption was investigated.It was found that although hydrophobicity of zeolite could be obtained by means of the surficial organic coating in the method of surface coating modification, partial channel of zeolite would be plugged, as a result, leading to the surface area reducing greatly.Distinctively, the framework element modification method could maintain not only complete lattice structure and adsorption capability of zeolite, but would also obtain a good hydrophobic property.Consequently, significant enhancement on gas absorption by this modified zeolite was achieved and up to a maxi-mum enhancement factor of 2.62.This shows that the solid particles with good enhancement role to gas absorption need not only good adsorptive capability but also certain hydrophobicity.An unsteady heterogeneous model was employed to predict enhancement factor and the calculated results agree well with the experimental data.
    The Separation of Catechol from Carbofuran Phenol by Extractive Distillation
    ZHANG Jianyu, HU Aixi, WANG Yu, XIAO Xuhui, GUO Jiabin, LUO Xianfu
    2009, 17(1):  42-46. 
    Abstract ( )   PDF (227KB) ( )  
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    In this study, extractive distillation has been applied to separate catechol(CAT) from carbofuran phenol(CFP) with high purity and yield.The relative volatility of CFP to CAT was measured, and the choice of separating agents was investigated.The experimental results indicated that CFP/CAT is an azeotropic system with an azeotropic point at 93.40℃/0.400 kPa and an azeotropic mixture containing 49.96% of CFP and 50.04% of CAT.Data from the determination of the relative volatility have shown that separating agents such as diglycol and 4-butylcatechol(4-TBC) are able to increase the relative volatility up to 1.90.In one shot process batch extractive distillation of CFP mixture with 3%(by mass) diglycol as separating agent, the purity and yield of the obtained CFP was 99.0% and 95.0%, respectively, while the distillation without separating agent provided a purity and yield of only 98.0% and 90.0%, respectively.There was no residual separating agent found in the product.
    Liquid Film Characteristics on Surface of Structured Packing
    LUO Shujuan, LI Huaizhi, FEI Weiyang, WANG Yun-dong
    2009, 17(1):  47-52. 
    Abstract ( )   PDF (275KB) ( )  
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    Structured packing is a good candidate for CO2 capture process because of its higher mass transfer efficiency and lower pressure drop.Now, the challenging problem of CO2 capture and storage demands more and more efficiency equipment.The aim of the present study is to investigate the liquid film characteristics under counter current gas phase and throw some insight into the enhancing mechanism of mass transfer performance in structured packing.A high speed digital camera, non-intrusive measurement technique, was used.Water and air were working fluids.Experiments were carried out for different gas/liquid flow rates and different inclination angles.The time-average and instantaneous film widths for each set of flow parameters were calculated.It is shown that the effects of gas phase could be neglected for lower flow rate, and then, become more pronounced at higher flow rate.According to instantaneous film width, three different stages can be distinguished.One is the constant width of liquid film.The second is the slight decrease of film width and the smooth surface.This kind of character will lead to less interfacial area and deteriorate the packing mass transfer performance.For the third stage, the variation of film width shows clearly chaotic behavior.The prediction model was also developed in present work.The predicted and experimental results are in good agreement.
    The Fouling Mechanism of Ceramic Membranes Used for Recovering TS-1 Catalysts
    ZHONG Zhaoxiang, LI Dongyan, LIU Xin, XING Weihong, XU Nanping
    2009, 17(1):  53-57. 
    Abstract ( )   PDF (351KB) ( )  
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    Ceramic ultrafiltration membranes were used to separate titanium silicalite-1(TS-1) catalysts from the slurry of catalytic ammoximation of cyclohexanone to oxime.Silica was shown to have a great effect on membrane fouling in the alkaline environment of this system.In the ammoximation system, there are three main silica sources, which are residual silica on the catalyst particles surface during preparation, silica dissolved from TS-1 catalyst particles by ammonia solvent, and silica sol added into the reaction slurry to inhibit the dissolution erosion of the TS-1 catalyst.The silica dissolved by ammonia has been proved to influence membrane fouling most among the three silica sources.This was because the amount of silica dissolved by ammonia was the largest, and the polymerization of silica monomers at high concentration caused colloid particles formation, which led to a dense cake layer depositing on the membrane surface.Meanwhile, the size reduction of catalyst particles caused by alkaline dissolution also increased specific resistances of cake layers.
    CATALYSIS, KINETICS AND REACTORS
    Preparation, Characterization and Catalytic Behavior of 12-Molybdophosphoric Acid Encapsulated in the Supercage of Cs+-exchanged Y Zeolite
    WEI Ruiping, GUO Maiping, WANG Jun
    2009, 17(1):  58-63. 
    Abstract ( )   PDF (229KB) ( )  
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    In order to solve the serious leaching problem of supported heteropoly acid catalysts in polar reaction media, 12-molybdophosphoric acid encapsulated in the supercage of Cs+-exchanged Y zeolite was prepared by the "ship in the bottle" synthesis.The influence of ion-exchange conditions and the synthesis parameters on the encapsulation of PMo12 were investigated.The obtained solid sample was characterized by X-ray diffraction(XRD), 31P magic angle spin nuclear magnetic resonance(MAS NMR) and Fourier Transform Infrared Spectroscopy(FT-IR), and its catalytic activity in the esterification of acetic acid and n-butanol was tested.The ion-exchange time, concentration of aqueous Cs+ solution, pH value, and amount of Mo added in the synthesis mixture were revealed to influence the encapsulation very remarkably.Under the optimal conditions, 12-molybdophosphoric acid could be successfully encapsulated in the supercage of CsY zeolite, and the samples showed considerable catalytic activity and excellent reusability in the esterification reaction.
    Steam Reforming of Dimethyl Ether over Coupled Catalysts of CuO-ZnO-Al2O3-ZrO2 and Solid-acid Catalyst
    FENG Dongmei, ZUO Yizan, WANG Dezheng, WANG Jinfu
    2009, 17(1):  64-71. 
    Abstract ( )   PDF (644KB) ( )  
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    Steam reforming(SR) of dimethyl ether(DME) was investigated for the production of hydrogen for fuel cells.The activity of a series of solid acids for DME hydrolysis was investigated.The solid acid catalysts were ZSM-5 [Si/Al=25, 38 and 50:denoted Z(Si/Al)] and acidic alumina(γ-Al2O3) with an acid strength order that was Z(25)>Z(38)>Z(50)>γ-Al2O3.Stronger acidity gave higher DME hydrolysis conversion.Physical mixtures containing a CuO-ZnO-Al2O3-ZrO2 catalyst and solid acid catalyst to couple DME hydrolysis and methanol SR were used to examine the acidity effects on DME SR.DME SR activity strongly depended on the activity for DME hydrolysis.Z(25) was the best solid acid catalyst for DME SR and gave a DME conversion>90% [T=24℃, n(H2O)/n(DME)=3.5, space velocity=1179 ml·(g cat)-1·h-1, and P=0.1MPa].The influences of the reaction temperature, space velocity and feed molar ratio were studied.Hydrogen production significantly depended on temperature and space velocity.A bifunctional catalyst of CuO-ZnO-Al2O3-ZrO2 catalyst and ZSM-5 gave a high H2 production rate and CO2 selectivity.
    Kinetics of 2-Methyl-6-acetyl-naphthalene Liquid Phase Catalytic Oxidation
    TIAN Wenyu, XUE Weilan, ZENG Zuoxiang, SHAO Ji
    2009, 17(1):  72-77. 
    Abstract ( )   PDF (242KB) ( )  
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    In this paper, a kinetics model for the liquid-phase oxidation of 2-methyl-6-acetyl-naphthalene to 2, 6-naphthalene dicarboxylic acid catalyzed by cobalt-manganese-bromide is proposed.The effects of the reaction temperature, catalyst concentration and ratio of catalyst on the time evolution of the experimental concentration for the constituents including raw material, intermediates and product are investigated.The model parameters are determined in a nonlinear optimization, minimizing the difference between the simulated and experimental time evolution of the product composition obtained in a semi-batch oxidation reactor where the gas and liquid phase were well mixed.The kinetics data demonstrate that the model is suitable to the liquid-phase oxidation of 2-methyl-6-acetyl-naphthalene to 2, 6-naphthalene dicarboxylic acid.
    Establishment of Kinetic Model for Catalytic Pyrolysis of Daqing Atmospheric Residue
    LIU Yibin, CHEN Xiaobo, ZHAO Hui, YANG Chaohe
    2009, 17(1):  78-82. 
    Abstract ( )   PDF (241KB) ( )  
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    An 8-lump kinetic model was proposed to predict the yields of propylene, ethylene and gasoline in the catalytic pyrolysis process of Daqing atmospheric residue.The model contains 21 kinetic parameters and one for catalyst deactivation.A series of experiments were carried out in a riser reactor over catalyst named LTB-2.The kinetic parameters were estimated by using sub-model method, and apparent activation energies were calculated according to the Arrhenius equation.The predicted yields coincided well with the experimental values.It shows that the kinetic parameters estimated by using the sub-model method were reliable.
    The Kinetics of the Esterification of Free Fatty Acids in Waste Cooking Oil Using Fe2(SO4)3/C Catalyst
    GAN Mengyu, PAN Deng, MA Li, YUE En, HONG Jianbing
    2009, 17(1):  83-87. 
    Abstract ( )   PDF (239KB) ( )  
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    The esterification of free fatty acids(FFA) in waste cooking oil with methanol in the presence of Fe2(SO4)3/C(ferric sulfate/active carbon) catalyst was studied.The effects of different temperature, methanol/FFA mole ratio and amount of catalyst on the conversion of FFA were investigated.The results demonstrated that under optimal esterification conditions the final acid value of the resultant system can be reduced to ~1(mg KOH)·g-1, which met fully the requirements in post-treatment for efficient separation of glycerin and biodiesel.The kinetics of the esterification were also investigated under different temperatures.The results indicated that the rate-control step could be attributed to the surface reaction and the esterification processes can be well-depicted by the as-calculated kinetic formula in the range of the experimental conditions.
    Methanol Synthesis from CO2 Hydrogenation with a Cu/Zn/Al/Zr Fibrous Catalyst
    AN Xin, ZUO Yizan, ZHANG Qiang, WANG Jinfu
    2009, 17(1):  88-94. 
    Abstract ( )   PDF (249KB) ( )  
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    A highly active Cu/Zn/Al/Zr fibrous catalyst was developed for methanol synthesis from CO2 hydrogenation.Various factors that affect the activity of the catalyst, including the reaction temperature, pressure and space velocity, were investigated.The kinetic parameters in Graaf’s kinetic model for methanol synthesis were obtained.A quasistable economical process for CO2 hydrogenation through CO circulation was simulated and higher methanol yield was obtained.
    PROCESS SYSTEMS ENGINEERING
    Multiple Model Soft Sensor Based on Affinity Propagation, Gaussian Process and Bayesian Committee Machine
    LI Xiuliang, SU Hongye, CHU Jian
    2009, 17(1):  95-99. 
    Abstract ( )   PDF (204KB) ( )  
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    Presented is a multiple model soft sensing method based on Affinity Propagation(AP), Gaussian process(GP) and Bayesian committee machine(BCM).AP clustering arithmetic is used to cluster training samples according to their operating points.Then, the sub-models are estimated by Gaussian Process Regression(GPR).Finally, in order to get a global probabilistic prediction, Bayesian committee machine is used to combine the outputs of the sub-estimators.The proposed method has been applied to predict the light naphtha end point in hydrocracker fractionators.Practical applications indicate that it is useful for the online prediction of quality monitoring in chemical processes.
    An Improved Fuzzy Predictive Control Algorithm and Its Application to an Industrial CSTR Process
    LU Mei, JIN Chengbo, SHAO Huihe
    2009, 17(1):  100-107. 
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    A finite horizon predictive control algorithm, which applies a saturated feedback control law as its local control law, is presented for nonlinear systems with time-delay subject to input constraints.In the algorithm, N free control moves, a saturated local control law and the terminal weighting matrices are solved by a minimization problem based on linear matrix inequality(LMI) constraints online.Compared with the algorithm with a nonsaturated local law, the presented algorithm improves the performances of the closed-loop systems such as feasibility and optimality.This model predictive control(MPC) algorithm is applied to an industrial continuous stirred tank reactor(CSTR) with explicit input constraint.The simulation results demonstrate that the presented algorithm is effective.
    Modeling and Simulation of Production Process on Dimethyl Ether Synthesized from Coal-based Syngas by One-step Method
    HAN Yuanyuan, ZHANG Haitao, YING Weiyong, FANG Dingye
    2009, 17(1):  108-112. 
    Abstract ( )   PDF (126KB) ( )  
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    As a result of shortage supply of oil resources, the process for the alternative coal-based fuel, dimethyl ether(DME), has emerged as an important process in chemical engineering field.With the laboratory experiment data about DME synthesis and separation, the production process for DME with high purity is proposed when one-step synthesis of DME in slurry bed reactor from syngas is adopted.On the basis of experimental research and process analysis, the proper unit modules and thermophysical calculation methods for the simulation process are selected.Incorporated the experimentally determined parameters of reaction dynamic model for DME synthesis, regression constants of parameters in non-random two-liquid equation(NRTL) model for binary component in DME separation system with built-in properties model, the process flowsheet is developed and simulated on the Aspen Plus platform.The simulation results coincide well with data obtained in laboratory experiment.Accordingly, the accurate simulation results offer useful references to similar equipment design and process operation optimization.
    A Strategy for the Integration of Production Planning and Scheduling in Refineries under Uncertainty
    LUO Chunpeng, RONG Gang
    2009, 17(1):  113-127. 
    Abstract ( )   PDF (360KB) ( )  
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    A strategy for the integration of production planning and scheduling in refineries is proposed.This strategy relies on rolling horizon strategy and a two-level decomposition strategy.This strategy involves an upper level multiperiod mixed integer linear programming(MILP) model and a lower level simulation system, which is extended from our previous framework for short-term scheduling problems [Luo, C.P., Rong, G., "Hierarchical approach for short-term scheduling in refineries", Ind.Eng.Chem.Res., 46, 3656-3668(2007)].The main purpose of this extended framework is to reduce the number of variables and the size of the optimization model and, to quickly find the optimal solution for the integrated planning/scheduling problem in refineries.Uncertainties are also considered in this article.An integrated robust optimization approach is introduced to cope with uncertain parameters with both continuous and discrete probability distribution.
    THERMODYNAMICS AND CHEMICAL ENGINEERING DATA
    The Dependence of the Dissociation Rate of Methane-SDS Hydrate below Ice Point on Its Manners of Forming and Processing
    WANG Xiulin, CHEN Guangjin, SUN Changyu, YANG Lanying, MA Qinglan, CHEN Jun, LIU Peng, TANG Xu-long, ZHAO Huanwei, CHEN Weidong
    2009, 17(1):  128-135. 
    Abstract ( )   PDF (249KB) ( )  
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    The dissociation rates of methane hydrates formed with and without the presence of sodium dodecyl sulfate(methane-SDS hydrates), were measured under atmospheric pressure and temperatures below ice point to investigate the influence of the hydrate production conditions and manners upon its dissociation kinetic behavior.The experimental results demonstrated that the dissociation rate of methane hydrate below ice point is strongly dependent on the manners of hydrate formation and processing.The dissociation rate of hydrate formed quiescently was lower than that of hydrate formed with stirring;the dissociation rate of hydrate formed at lower pressure was higher than that of hydrate formed at higher pressure;the compaction of hydrate after its formation lowered its stability, i.e., increased its dissociation rate.The stability of hydrate could be increased by prolonging the time period for which hydrate was held at formation temperature and pressure before it was cooled down, or by prolonging the time period for which hydrate was held at dissociation temperature and formation pressure before it was depressurized to atmospheric pressure.It was found that the dissociation rate of methane hydrate varied with the temperature(ranging from 245.2 to 272.2 K) anomalously as reported on the dissociation of methane hydrate without the presence of surfactant as kinetic promoter.The dissociation rate at 268 K was found to be the lowest when the manners and conditions at which hydrates were formed and processed were fixed.
    Isobaric Vapor-Liquid Equilibrium of Binary System 2-Cyclohexen-1-one and 1, 2-Epoxycyclohexane
    WANG Xuemeng, JIANG Denggao, GENG Zaixin
    2009, 17(1):  136-139. 
    Abstract ( )   PDF (250KB) ( )  
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    Green oxidation of cyclohexene using dioxygen as oxidizing agent is highly desirable because of its environmental compatibility and economic impact.Separation of its oxidation products depends on the reliable vaporliquid equilibrium(VLE) data of relevant components, which are still lacking.The VLE data of binary system 1, 2-epoxycyclohexane and 2-cyclohexen-1-one under ambient pressure were obtained using an improved VLE equipment EC-2 still in this work.The results showed that this binary system has no azeotropic point.Furthermore, the experimental VLE data were correlated with the Wilson thermodynamic model and the corresponding binary interaction parameters of the model were obtained.The results showed that the VLE data agreed well with the model and passed the thermodynamic consistency test of Herrington.
    Measurement and Correlation of Solid-Liquid Equilibria of Phenyl Salicylate with C4 Alcohols
    WEI Dongwei, PEI Yanhong, ZHANG Chao, YAN Feng
    2009, 17(1):  140-144. 
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    In an equilibrium vessel, the solid-liquid equilibria(SLE) for three binary mixtures of phenyl salicylate with 1-butanol, 2-butanol, and 2-methyl-1-propanol, respectively, have been measured from 283.15 K to the melting temperature of the solute using a method in which an excess amount of solute was equilibrated with the alcohol solution.The liquid concentrations of the investigated phenyl salicylate in the saturated solution were analyzed by UV spectrometry.Activity coefficients for phenyl salicylate have been calculated by means of the Wilson, NRTL, and UNIQUAC equations and with them were correlated solubility data that were compared with the experimental ones.The best correlation of the solubility data has been obtained by the Wilson equation by which the average root-mean-square deviation of temperature for the three systems is 1.03 K.
    BIOTECHNOLOGY AND BIOENGINEERING
    Synthesis and Characterization of Novel Temperature and pH Responsive Hydroxylpropyl Cellulose-based Graft Copolymers
    LI Xiaojun, YIN Minghui, ZHANG Guoliang, ZHANG Fengbao
    2009, 17(1):  145-149. 
    Abstract ( )   PDF (244KB) ( )  
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    In this study, double-hydrophilic hydroxylpropyl cellulose(HPC) based copolymers with poly(N-isopropylacrylamide)(PNIPAM) and poly(acrylic acid)(PAA) as graft chains were synthesized and characterized.The release behavior of drug-loaded micelles was studied.The results show that the hydrophilicity of copolymers improves as the pH increases, whereas the hydrophobicity of copolymers enhances as the temperature increases, and all the phase behaviors are reversible.The diameter of micelles decreases and then increases with pH increase.It shows different micellizing behavior under acidic and basic conditions according to the temperature increase.In vitro release experiments, which used theophylline as a model drug, show that the micelles enhance pH sensitivity in the release process.
    PRODUCT ENGINEERING AND CHEMICAL TECHNOLOGY
    Electrochemical Performance of Nickel Hydroxide/Activated Carbon Supercapacitors Using a Modified Polyvinyl Alcohol Based Alkaline Polymer Electrolyte
    SUN Zihong, YUAN Anbao
    2009, 17(1):  150-155. 
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    Polyvinyl alcohol(PVA)-sodium polyacrylate(PAAS)-KOH-H2O alkaline polymer electrolyte film with high ionic conductivity was prepared by a solution-casting method.Polymer Ni(OH)2/activated carbon(AC) hybrid supercapacitors with different electrode active material mass ratios(positive to negative) were fabricated using this alkaline polymer electrolyte, nickel hydroxide positive electrodes, and AC negative electrodes.Galvanostatic charge/discharge and electrochemical impedance spectroscopy(EIS) methods were used to study the electrochemical performance of the capacitors, such as charge/discharge specific capacitance, rate charge/discharge ability, and charge/discharge cyclic stability.Experimental results showed that with the decreasing of active material mass ratio m(Ni(OH)2)/m(AC), the charge/discharge specific capacitance increases, but the rate charge/discharge ability and the charge/discharge cyclic stability decrease.
    Dyeability of Polylactide Fabric with Hydrophobic Anthraquinone Dyes
    HE Liang, ZHANG Shufen, TANG Bingtao, WANG Lili, YANG Jinzong
    2009, 17(1):  156-159. 
    Abstract ( )   PDF (205KB) ( )  
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    The dyeability of polylactide fabric has been investigated with the substituted aminoanthraquinone hydrophobic dyes.Their application to the polylactide fabric led to good exhaustion values and good wash fastness between 4 and 5.Microscopic assessment of cross-sections of the dyed polylactide fibres confirmed that these dyes could penetrate into the fibres.The nature of the substituted amino groups showed little influence on the wash fastness, but clearly influenced the exhaustion and light fastness.
    Purification of Sulfuric and Hydriodic Acids Phases in the Iodine-sulfur Process
    BAI Ying, ZHANG Ping, GUO Hanfei, CHEN Songzhe, WANG Laijun, XU Jingming
    2009, 17(1):  160-166. 
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    Iodine-sulfur(IS) thermochemical water-splitting cycle is the most promising massive hydrogen production process.To avoid the undesirable side reactions between hydriodic acid(HI) and sulfuric acid(H2SO4), it is necessary to purify the two phases formed by the Bunsen reaction.The purification process could be achieved by reverse reaction of the Bunsen reaction.In this study, the purification of the H2SO4 and HI Phases was studied.The purification proceeded in both batches and the continuous mode, the influences of operational parameters, including the reaction temperature, the flow rate of nitrogen gas, and the composition of the raw material solutions, on the purification effect, were investigated.Results showed that the purification of the H2SO4 phase was dominantly affected by the reaction temperature, and iodine ion in the sulfuric acid phase could be removed completely when the temperature was above 130℃;although, the purification effect of the HI phase improved with increasing of both the flow rate of nitrogen gas and temperature.
    The Role of Diatomite Particles in the Activated Sludge System for Treating Coal Gasification Wastewater
    ZHANG Wenqi, RAO Pinhua, ZHANG Hui, XU Jingli
    2009, 17(1):  167-170. 
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    Diatomite is a kind of natural low-cost mineral material.It has a number of unique physical properties and has been widely used as an adsorbent in wastewater treatment.This study was conducted to investigate the aerobic biodegradation of coal gasification wastewater with and without diatomite addition.Experimental results indicated that diatomite added in the activated sludge system could promote the biomass and also enhance the performance of the sludge settling.The average mixed-liquor volatile suspended solids(MLVSS) is increased from 4055 mg·L-1 to 4518 mg·L-1 and the average settling volume(SV) are changed only from 45.9% to 47.1%.Diatomite additive could enhance the efficiency of chemical oxygen demand(COD) and total phenols removal from the wastewater.The COD removal increased from 73.3% to near 80% and the total phenols removal increased from 81.4% to 85.8%.The mechanisms of the increase of biomass and pollutants removal may correlates to the improvement of bioavailability and sludge settlement characteristics by diatomite added.Micrograph of the sludge in the diatomite-activated sludge system indicated that the diatomite added could be the carrier of the microbe and also affect the biomass and pollutant removal.
    RESEARCH NOTES
    Rapid and Continuous Production of LiFePO4/C Nanoparticles in Super Heated Water
    YU Wenli, ZHAO Yaping, RAO Qunli
    2009, 17(1):  171-174. 
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    A rapid and continuous method for production of LiFePO4/C nanoparticles in super heated water is described, wherein soluble starch was used as carbon precursor.The effects of pH, flow rate, temperature, and pressure on the formation of LiFePO4/C particles were investigated.Results showed that the pH value was the key factor on the formation of phase pure LiFePO4, which only formed at pH=7;the LiFePO4/C occurred as particles with about 70-200 nm size and LiFePO4 was covered by a thin carbon layer;higher flow rate, higher pressure, and lower temperature led to smaller particles of LiFePO4/C.
    Numerical Investigation of Constructal Distributors with Different Configurations
    FAN Zhiwei, ZHOU Xinggui, LUO Ling’ai, YUAN Weikang
    2009, 17(1):  175-178. 
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    Seven distributors with different configurations are designed and optimized by constructal approach.Their flow distribution performance and energy dissipation are investigated and compared by computational fluid dynamics(CFD) simulation.The reliability of CFD simulation is verified by experiments on the distributor that has all distributing rectangle channels on a plate.The results show that the symmetry of the distributing channels has decisive influence on the performance of flow distribution.Increasing the generations of channel branching will improve the flow distribution uniformity, but on the other hand increase the energy dissipation.Among all the seven constructal distributors, the distributor that has dichotomy configuration, Y-type junctions and straight interconnecting channels, is recommended for its better flow distribution performance and less energy dissipation.