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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 December 2011, Volume 19 Issue 6
    PERSPECTIVES
    Stimuli-responsive Membranes: Smart Tools for Controllable Mass-transfer and Separation Processes
    CHU Liangyin, XIE Rui, JU Xiaojie
    2011, 19(6):  891-903. 
    Abstract ( )   PDF (2557KB) ( )  
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    As emerging artificial biomimetic membranes, smart or intelligent membranes that are able to respond to environmental stimuli are attracting ever-increasing interests from various fields. Their permeation properties including hydraulic permeability and diffusional permeability can be dramatically controlled or adjusted self-regulatively in response to small chemical and/or physical stimuli in their environments. Such environmental stimuli-responsive smart membranes could find myriad applications in numerous fields ranging from controlled release to separations. Here the trans-membrane mass-transfer and membrane separation is introduced as the beginning to initiate the requirement of smart membranes, and then bio-inspired design of environmental stimuli-responsive smart membranes and four essential elements for smart membranes are introduced and discussed. Next, smart membrane types and their applications as smart tools for controllable mass-transfer in controlled release and separations are reviewed. The research topics in the near future are also suggested.
    SEPARATION SCIENCE AND ENGINEERING
    Pretreatment of Isopropanol Solution from Pharmaceutical Industry and Pervaporation Dehydration by NaA Zeolite Membranes
    YU Congli, LIU Yanmei, CHEN Gangling, GU Xuehong, XING Weihong
    2011, 19(6):  904-910. 
    Abstract ( )   PDF (8217KB) ( )  
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    NaA zeolite membranes with 80 cm in length and 12.8 mm in outer diameter were prepared by our research group cooperating with Nanjing Jiusi Hi-Tech Co., China. The influence of dissolved inorganic salts and pH value in the feed of isopropanol (IPA) solution on NaA zeolite membranes was investigated. It was found that both factors exhibited strong influence on the stability of NaA zeolite membranes. A set of pretreatment steps such as pH adjustment and distillation of the IPA solution were proposed to improve stability for pervaporation dehydration. An industrial-scale pervaporation facility with 52 m2 membrane area was built to dehydrate IPA solution from industrial cephalosporin production. The facility was continuously operated at 368-378 K to dehydrate IPA solution from water mass content of 15%-20% to less than 2% with a feed flow rate of 400-500 L·h-1 and an average water flux of 1-1.5 kg·m-2·h-1. The successful application of this facility suggested a promising application of NaA zeolite mem-brane for IPA recovery from pharmaceutical production.
    Pinch Point Calculations and Its Implications on Robust Distillation Design
    Daniel A. Beneke, Seon B. Kim, Andreas A. Linninger
    2011, 19(6):  911-925. 
    Abstract ( )   PDF (733KB) ( )  
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    Rising energy costs and growing environmental awareness motivate a critical revision of the design of distillation units. Systematic design techniques, such as the rectification body, column profile map, and temperature collocation methods, require exact knowledge of all pinch points in a particular system, because these stationary points delineate the possible composition trajectories realizable in separation columns. This paper demonstrates novel methods for rigorously determining all pinch points for the constant relative volatility, ideal and non-ideal systems. Constant relative volatility and ideal solution systems are transformed into one-dimensional polynomial and nonlinear functions, regardless of the number of the components. A deflation method is proposed to locate all zeros in ideal and non-ideal zeotropic problems. For more challenging non-ideal problems, a novel hybrid sequential niche algorithm is used to solve hard azeotropic problems successfully. Finally, the design implications of these pinch point locations are investigated to show how new separation configurations can be devised. Methodically the paper points out the use of rigorous pinch point computations in conjunction with continuous composition profiles for robust distillation design.
    Recovery of Copper(II) and Nickel(II) from Plating Wastewater by Solvent Extraction
    LI Liqing, ZHONG Hong, CAO Zhanfang, YUAN Lu
    2011, 19(6):  926-930. 
    Abstract ( )   PDF (185KB) ( )  
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    The solvent extraction technology was applied to recover Cu2+ and Ni2+ from plating wastewater. Lix984N was chosen as the extractant due to its good extraction performance. The influence parameters were examined. The results show that the separation of Cu2+ and Ni2+ from sulphate medium can be realized by adjusting pH value with the help of Lix984N. For extracting Cu2+ and Ni2+, the optimal pH values are 4 and 10.5, and the maximal extraction percentages are 92.9% and 93.0%, respectively. With recovered Cu2+ and Ni2+ stripped in 170 g·L-1 and 200 g·L-1 H2SO4 medium, the stripping percentages of Cu2+ and Ni2+ are 92.9% and 93.0%, respectively. This method is simple and can be used to recover Cu2+ and Ni2+ from plating wastewater. And a flow sheet for separation of Cu2+ and Ni2+ is presented.
    Surface and Hydrogen Sorption Characteristics of Various Activated Carbons Developed from Rat Coal Mine (Zonguldak) and Anthracite
    Atakan Toprak, Turkan Kopac
    2011, 19(6):  931-937. 
    Abstract ( )   PDF (259KB) ( )  
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    Activated carbon samples were developed from coal samples obtained from a coal mine, rat (Zonguldak, Turkey) and anthracite (Siberia, Russia), applying pyrolysis in a temperature range of 600-900℃ under N2 flow, and activation using chemical agents such as KOH, NH4Cl, ZnCl2 at 650℃. Nitrogen adsorption at low temperature (77 K) was used to characterize the activated carbon samples, and their pore structure properties including pore volume, pore diameter and pore size distribution were determined by means of the t-plots and DFT methods. The surface area values were higher for rat coal samples than for anthracite one, and for the rat coal samples treated with KOH+NH4Cl+ZnCl2 at 650℃ [Rat650(2)] there are highest surface area and total pore volume, 315.6 m2·g-1 and 0.156 ml·g-1, respectively. The highest value of the hydrogen sorption capacity was found as 0.71% (by mass) for the rat coal sample obtained by KOH+ZnCl2 treatment at 650℃ [Rat650(1)].
    Removal of Nitrophenols by Adsorption Using β-Cyclodextrin Modified Zeolites
    LI Xiaohong, ZHAO Baowei, ZHU Kun, HAO Xuekui
    2011, 19(6):  938-943. 
    Abstract ( )   PDF (291KB) ( )  
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    Removal of nitrophenols (NPs) from aqueous solutions through the adsorption process by using cationic β-cyclodextrin (CCD) modified zeolite (CCDMZ) was investigated. The effects of particle size, contact time, solution pH values and sodium chloride content in the aqueous on adsorption capacity were evaluated through a series of batch experiments. The results showed that CCDMZ had a higher adsorption capacity for removing NPs at a size fraction of 0.45-0.9 mm while adsorption of NPs on CCDMZ reached equilibrium within 60 min. The adsorption process was apparently influenced by pH values and sodium chloride content in aqueous solution. To ascertain the mechanisms of sorption, the experimental data were modeled by using the pseudo-first and pseudo-second order kinetic equations, and the results indicated that the adsorption kinetics of NPs on CCDMZ well-matched with the pseudo-second order rate expression.
    FLUID FLOW AND TRANSPORT PHENOMENA
    Laminar Forced Convection Heat and Mass Transfer of Humid Air across a Vertical Plate with Condensation
    LI Cheng, LI Junming
    2011, 19(6):  944-954. 
    Abstract ( )   PDF (1251KB) ( )  
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    Condensation of humid air along a vertical plate was numerically investigated, with the mathematical model built on the full boundary layer equations and the film-wise condensation assumption. The velocity, heat and mass transfer characteristics at the gas-liquid interface were numerical analyzed and the results indicated that it was not reasonable to neglect the condensate film from the point of its thickness only. The condensate film thickness, interface temperature drop and the interface tangential velocity affect the physical fields weakly. However, the subcooling and the interface normal velocity were important factors to be considered before the simplification was made. For higher wall temperature, the advective mass transfer contributed much to the total mass transfer. Therefore, the boundary conditions were the key to judge the rationality of neglecting the condensate film for numerical solutions. The numerical results were checked by comparing with experiments and correlations.
    Transport of Indium, Gallium and Thallium Metal Ions Through Chromatographic Fiber Supported Solid Membrane in Acetylacetone Containing Mixed Solvents
    Abaji Gaikwad
    2011, 19(6):  955-963. 
    Abstract ( )   PDF (280KB) ( )  
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    The transport of metal ions of indium, gallium and thallium from source solution to receiving phase through the chromatographic fiber supported solid membrane in the acetylacetone (HAA) containing mixed solvent system has been explored. The fibers supported solid membranes were prepared with chemical synthesis from cellulose fibers and citric acid with the carboxylic acid ion exchange groups introduced. The experimental variables, such as concentration of metal ions (10-2 to 10-4 mol·L-1) in the source solution, mixed solvent composition [for example, acetylacetone, (2,4-pentanedione), (HAA) 20% (by volume), 1,4-dioxane 10% to 60% and HCl 0.25 to 2 mol·L-1] in the receiving phase and stirring speed (50-130 r·min-1) of the bulk source and receiving phase, were explored. The efficiency of mixed solvents for the transport of metal ions from the source to receiving phase through the fiber supported solid membrane was evaluated. The combined ion exchange solvent extraction (CIESE) was observed effective for the selective transport of thallium, indium and gallium metal ions through fiber supported solid membrane in mixed solvents. The oxonium salt formation in the receiving phase enhances thallium, indium and gallium metal ion transport through solid membrane phase. The selective transport of thallium metal ions from source phase was observed from indium and gallium metal ions in the presence of hydrochloric acid in organic solvents in receiving phase. The separation of thallium metal ions from the binary mixtures of Be(II), Ti(IV), Al(III), Ca(II), Mg(II), K (I), La(III) and Y(III) was carried out in the mixed solvent system using cellulose fiber supported solid membrane.
    CATALYSIS, KINETICS AND REACTORS
    Kinetics of Formic Acid-autocatalyzed Preparation of Performic Acid in Aqueous Phase
    SUN Xiaoying, ZHAO Xuebing, DU Wei, LIU Dehua
    2011, 19(6):  964-971. 
    Abstract ( )   PDF (300KB) ( )  
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    Performic acid (PFA) is an oxidant used in chemical processing, synthesis and bleaching. The macro kinetic models of synthesis, hydrolysis and decomposition of PFA were investigated via formic acid-autocatalyzed reaction. It was found that the intrinsic activation energies of PFA synthesis and hydrolysis were 75.2 kJ·mol-1 and 40.4 kJ·mol-1 respectively. The observed activation energy of PFA decomposition was 95.4 kJ·mol-1. The experimental results indicated that the decomposition of PFA was liable to occur even at the ambient temperature. Both the spontaneous decomposition and the radical-introduced decomposition contributed to the decomposition of PFA.
    β-Cyclodextrin Promoted Oxidation of Cinnamaldehyde to Natural Benzaldehyde in Water
    CHEN Hongyan, JI Hongbing
    2011, 19(6):  972-977. 
    Abstract ( )   PDF (269KB) ( )  
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    A facile and efficient procedure has been developed systematically for the oxidative cleavage of cinnamaldehyde to benzaldehyde by sodium hypochlorite with water as the only solvent in the presence of β-cyclodextrin (abbreviated as β-CD). Different factors influencing cinnamaldehyde oxidation e.g. reaction temperature, the amount of catalyst and oxidant, have been investigated. The yield of benzaldehyde reaches 76% under the optimum conditions (333 K, 4 h, molar ratio of cinnamaldehyde to β-CD is 1:1). Furthermore, a feasible reaction mechanism including the formation of benzaldehyde and the two main byproducts (phenylacetaldehyde and epoxide of cinnamaldehyde) has been proposed.
    Synthesis of Wax Esters by Lipase-catalyzed Esterification with Immobilized Lipase from Candida sp. 99-125
    DENG Li, WANG Xiaojing, NIE Kaili, WANG Fang, LIU Junfeng, WANG Pu, TAN Tianwei
    2011, 19(6):  978-982. 
    Abstract ( )   PDF (222KB) ( )  
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    Wax esters were synthesized in a solvent free system catalyzed by immobilized lipase from Candida sp. 99-125, with oleic acid and cetyl alcohol. The effects of substrate molar ratio, lipase dosage and water removal were investigated in a 50 ml flask incubated in a thermostatic cultivation cabinet. The optimized conditions were: temperature 40℃, shaking at 170 r·min-1, acid/alcohol molar ratio 1:0.9, lipase dosage in 10% (by mass) of oleic acid, and open reaction for water removal. As a result, the conversion rate reached 98% for reaction of 8 h. The volume of reactor was scaled up to 1 L three-neck flask. The optimized parameters were: 200 r·min-1 agitation speed, 2.5% (by mass) lipase dosage, others were the same as the parameters described above. The conversion rate reached 95% for reaction of 24 h. The lipase retained 46% conversion rate after reuse for 6, 7 batches. The products were purified by removing remained cetyl alcohol and fatty acids with ethanol and saturated sodium carbonate solution, respectively. The purity of the wax ester, cetyl oleate, was 96%. The physical and chemical properties of cetyl oleate were tested and compared with those of jojoba oil. The results show that the product cetyl oleate has great potential to use as the substitute of natural jojoba oil.
    PROCESS SYSTEMS ENGINEERING
    Simulation and Analysis on Multiple Steady States of an Industrial Acetic Acid Dehydration System
    LI Shaojun, HUANG Dingwei
    2011, 19(6):  983-989. 
    Abstract ( )   PDF (894KB) ( )  
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    In this work, an industrial acetic acid dehydration system via heterogeneous azeotropic distillation is simulated by Aspen Plus software. Residue curves are used to analyze the distillating behavior, and appropriate operating region of the system is determined. Based on steady states simulation, a sensitivity analysis is carried out to detect the output multiple steady states in the system. Different solution branches are observered when the flow rates of the feed stream and the organic reflux stream are selected as manipulated variables. The performance of the column under different steady states is different. A method is proposed to achieve the desired steady state.
    Modeling and Multi-objective Optimization of Refinery Hydrogen Network
    JIAO Yunqiang, SU Hongye, LIAO Zuwei, HOU Weifeng
    2011, 19(6):  990-998. 
    Abstract ( )   PDF (254KB) ( )  
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    The demand of hydrogen in oil refinery is increasing as market forces and environmental legislation, so hydrogen network management is becoming increasingly important in refineries. Most studies focused on singleobjective optimization problem for the hydrogen network, but few account for the multi-objective optimization problem. This paper presents a novel approach for modeling and multi-objective optimization for hydrogen network in refineries. An improved multi-objective optimization model is proposed based on the concept of superstructure. The optimization includes minimization of operating cost and minimization of investment cost of equipment. The proposed methodology for the multi-objective optimization of hydrogen network takes into account flow rate constraints, pressure constraints, purity constraints, impurity constraints, payback period, etc. The method considers all the feasible connections and subjects this to mixed-integer nonlinear programming (MINLP). A deterministic optimization method is applied to solve this multi-objective optimization problem. Finally, a real case study is introduced to illustrate the applicability of the approach.
    An Integrated Approach to Oscillation Propagation Identification and Source Locating in Process Multi-loop Systems
    CAO Jiabin, ZHANG Liang, ZHENG Jianrong, XIA Chunming
    2011, 19(6):  999-1008. 
    Abstract ( )   PDF (471KB) ( )  
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    An integrated method for identifying the propagation of multi-loop process oscillations and their source location is proposed in this paper. Oscillatory process loop variables are automatically selected based on the component-related ratio index and a mixing matrix, both of which are obtained in data preprocessing by spectral independent component analysis. The complex causality among oscillatory process variables is then revealed by Granger causality test and is visualized in the form of causality diagram. The simplification of causal connectivity in the diagram is performed according to the understanding of process knowledge and the final simplest causality diagram, which represents the main oscillation propagation paths, is achieved by the automated cutting-off thresh-old search, with which less significant causality pathways are filtered out. The source of the oscillation disturbance can be identified intuitively through the final causality diagram. Both simulated and real plant data tests are presented to demonstrate the effectiveness and feasibility of the proposed method.
    THERMODYNAMICS AND CHEMICAL ENGINEERING DATA
    Modeling pVT Properties and Vapor-Liquid Equilibrium of Ionic Liquids Using Cubic-plus-association Equation of State
    MA Jun, LI Jinlong, FAN Dongfu, PENG Changjun, LIU Honglai, HU Ying
    2011, 19(6):  1009-1016. 
    Abstract ( )   PDF (280KB) ( )  
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    Combining Peng-Robinson (PR) equation of state (EoS) with an association model derived from shield-sticky method (SSM) by Liu et al., a new cubic-plus-association (CPA) EoS is proposed to describe the thermodynamic properties of pure ionic liquids (ILs) and their mixtures. The new molecular parameters for 25 ILs are obtained by fitting the experimental density data over a wide temperature and pressure range, and the overall average deviation is 0.22%. The model parameter b for homologous ILs shows a good linear relationship with their molecular mass, so the number of model parameters is reduced effectively. Using one temperature-independent binary adjustable parameter kij, satisfactory correlations of vapor-liquid equilibria (VLE) for binary mixtures of ILs + non-associating solvents and + associating solvents are obtained with the overall average deviation of vapor pressure 2.91% and 7.01%, respectively. In addition, VLE results for ILs + non-associating mixtures from CPA, lattice-fluid (LF) and square-well chain fluids with variable range (SWCF-VR) EoSs are compared.
    BIOTECHNOLOGY AND BIOENGINEERING
    Medium Optimization for Improved Ethanol Production in Very High Gravity Fermentation
    HU Chunkeng, QIN Qing, GAO Peipei
    2011, 19(6):  1017-1022. 
    Abstract ( )   PDF (188KB) ( )  
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    An optimal medium (300 g·L-1 initial glucose) comprising 6.3 mmol·L-1 Mg2+, 5.0 mmol·L-1 Ca2+, 15.0 g·L-1 peptone and 21.5 g·L-1 yeast extract was determined by uniform design to improve very high gravity (VHG) ethanol fermentation, showing over 30% increase in final ethanol (from 13.1% to 17.1%, by volume), 29% decrease in fermentation time (from 84 to 60 h), 80% increase in biomass formation and 26% increase in glucose utilization. Experiments also revealed physiological aspects linked to the fermentation enhancements. Compared to the control, trehalose in the cells grown in optimal fermentation medium increased 17.9-, 2.8-, 1.9-, 1.8- and 1.9-fold at the fermentation time of 12, 24, 36, 48 and 60 h, respectively. Its sharp rise at the early stage of fermentation when there was a considerable osmotic stress suggested that trehalose played an important role in promoting fermentation. Meanwhile, at the identical five fermentation time, the plasma membrane ATPase activity of the cells grown in optimal medium was 2.3, 1.8, 1.6, 1.5 and 1.3 times that of the control, respectively. Their disparities in enzymatic activity became wider when the glucose levels were dramatically changed for ethanol production, suggesting this enzyme also contributed to the fermentation improvements. Thus, medium optimization for VHG ethanol fermentation was found to trigger the increased yeast trehalose accumulation and plasma membrane ATPase activity.
    Influence of Conditions on Reuterin Accumulation by the Resting Cell Biotransformation Process
    CHEN Guo, YANG Daomao, XIAO Yaqin, CHEN Hongwen
    2011, 19(6):  1023-1027. 
    Abstract ( )   PDF (180KB) ( )  
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    3-Hydroxypropionaldehyde (3-HPA) is a potential valuable chemical and new broad-spectrum antimicrobial substance. In order to improve the conversion of 3-HPA/glycerol, our work studied the two-step process from glycerol to 3-HPA, and investigated the influence of cell harvest time, glycerol concentration, biomass con-centration, pH and temperature on the production of 3-HPA by Lactobacillus reuteri CG001, respectively. The results showed that molar conversion yield of 3-HPA/glycerol reached 97.9% under the condition that 200 mmol·L-1 glycerol was converted by 25.3 g·L-1 resting cell for 1 h at 30℃. The cells could not be reused directly because the L. reuteri almost lost its bioconversion activity completely, but the ability of glycerol conversion could gradually recover if the fresh medium was added to the deactivated cell for 4 h.
    Asymmetric Bioreduction of 3,5-Bis(trifluoromethyl) Acetophenone to Its Corresponding Alcohol by Candida tropicalis
    WANG Pu, SU Huizhen, SUN Liming, HE Junyao, LÜ Yaping
    2011, 19(6):  1028-1032. 
    Abstract ( )   PDF (236KB) ( )  
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    (S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed in high enantiomeric excess (e.e.) through asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone catalyzed by Candida tropicalis 104 cells. The influence of some key reaction parameters such as substrate concentration, co-substrate and its concentration, biomass and reaction time was examined, respectively. The results showed that these factors obviously influence the yield, but the optical purity of the prepared product remains intact. The optimum conditions for the preparation of (S)-3,5-bistrifluoromethylphenyl ethanol were found to be as follows: substrate concentration 50 mmol·L-1; 50 g·L-1 of maltose as co-substrate; wet cell concentration 300 g·L-1; reaction for 30 h. Under above optimal conditions, the maximum yield for (S)-3,5-bistrifluoromethylphenyl ethanol reached 70.3% with 100% of product e.e.
    PRODUCT ENGINEERING AND CHEMICAL TECHNOLOGY
    Preparation of Ti/PTFE-F-PbO2 Electrode with a Long Life from the Sulfamic Acid Bath and Its Application in Organic Degradation
    HONG Xiaping, ZHANG Rong, TONG Shaoping, MA Chun’an
    2011, 19(6):  1033-1038. 
    Abstract ( )   PDF (5091KB) ( )  
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    A polytetrafluoroethylene (PTFE)-doped PbO2 electrode on a Ti substrate was prepared by galvanostatic method from the sulfamic acid bath (Ti/PTFE-F-PbO2-I) or nitric acid bath (Ti/PTFE-F-PbO2-II). Scanning Electron Microscopy revealed that the Ti/PTFE-PbO2-I electrode had a more regular morphology with smaller size crystals than the Ti/PTFE-F-PbO2-II electrode. On the basis of the results of both the accelerated electrolysis test and the empirical formula for estimating the service life of an electrode, the service life of the Ti/PTFE-PbO2-I electrode was predicted to be more than 7 years under conventional electrolysis conditions (0.1 A·cm-2). During the treatment of 4-chlorophenol- contaminated water, the Ti/PTFE-PbO2-I anode showed both a good electro-catalytic activity and high electrochemical stability, exhibiting an excellent potential application.
    Supercritical Antisolvent-based Technology for Preparation of Vitamin D3 Proliposome and Its Characteristics
    XIA Fei, JIN Heyang, ZHAO Yaping, GUO Xinqiu
    2011, 19(6):  1039-1046. 
    Abstract ( )   PDF (4308KB) ( )  
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    Vitamin D3 (VD3) proliposomes (VDP), consisted of hydrogenated phosphatidycholine (HPC) and VD3, were prepared using supercritical anti-solvent technology (SAS). The effects of operation conditions (temperature, pressure and components) on the VD3 loading in VDP were studied. At the optimum conditions of pressure of 8.0 MPa, temperature of 45℃, and the mass ratio of 15.0% between VD3 and HPC, the VD3 loading reached 12.89%. VD3 liposomes (VDL) were obtained by hydrating VDP and the entrapment efficiency of VD3 in VDL reached 98.5%. The morphology and structure of VDP and VDL were characterized by SEM (scanning electron microscope), TEM (transmission electron microscope) and XRD (X-ray diffractometer). The structure of VD3 nanoparticles in HPC matrix was formed. The size of VDL with an average diameter of about 1μm was determined by dynamic light scattering instrument (DLS). The results indicated that VDP can be made by SAS and VDL with high entrapment efficiency can be formed easily via the hydration of VDP.
    Preparation of Nano-MnFe2O4 and Its Catalytic Performance of Thermal Decomposition of Ammonium Perchlorate
    HAN Aijun, LIAO Juanjuan, YE Mingquan, LI Yan, PENG Xinhua
    2011, 19(6):  1047-1051. 
    Abstract ( )   PDF (1855KB) ( )  
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    Nano-MnFe2O4 particles were synthesized by co-precipitation phase inversion method and low-temperature combustion method respectively, using MnCl2, FeCl3, Mn(NO3)2, Fe(NO3)3, NaOH and C6H8O7. X-ray diffraction (XRD), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry-differential thermal analysis (TG-DTA) and differential scanning calorimetry (DSC) were used to characterize the structure, morphology, thermal stability of MnFe2O4 and its catalytic performance to ammonium perchlorate. Results showed that single-phased and uniform spinel MnFe2O4 was obtained. The average particle size was about 30 and 20 nm. The infrared absorption peaks appeared at about 420 and 574 cm-1, and the particles were stable below 524℃. Using the two prepared catalysts, the higher thermal decomposition temperature of ammonium perchlorate was decreased by 77.3 and 84.9℃ respectively, while the apparent decomposition heat was increased by 482.5 and 574.3 J·g-1. The catalytic mechanism could be explained by the favorable electron transfer space provided by outer d orbit of transition metal ions and the high specific surface absorption effect of MnFe2O4 particles.
    Implication of Geochemical Simulation for CO2 Storage Using Data of York Reservoir
    YANG Zihao, JIN Min, LI Mingyuan, DONG Zhaoxia, YAN Peng
    2011, 19(6):  1052-1059. 
    Abstract ( )   PDF (761KB) ( )  
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    In this paper, we build up a three-dimensional model for CO2 storage in the deep reservoir. And this paper gives the mathematical formalism of combined geochemical and multi-phase flow. The results give us the information about geochemical changing caused by CO2 injection into aqueous, the dissolution or precipitation of reservoir minerals caused by aqueous components change, the change of water density, also the differences between this model and the simulation model without considering geochemical. The basic data for simulation is from York Reservoir.
    RESEARCH NOTES
    Effects of Pulse Ultrasound on Adsorption of Geniposide on Resin 1300 in a Fixed Bed
    LU Xianghong, XU Zhichao, JI Jianbing
    2011, 19(6):  1060-1065. 
    Abstract ( )   PDF (825KB) ( )  
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    The effects of pulse ultrasound with different pulse parameters on the breakthrough curves of Geniposide on Resin 1300 were studied. The mass transfer model describing the adsorption process was constructed. Adsorption capability and the overall mass-transfer coefficient were obtained by fitting the constructed mass-transfer model and the experimental data. The effects of pulse ultrasound on adsorption of Geniposide on Resin1300 in a fixed bed were studied and compared. Amount of Geniposide adsorbed on Resin 1300 in the presence of ultrasound is lower than that in the absence of ultrasound, but the mass-transfer rate with ultrasonic irradiation is higher than that without ultrasound. Furthermore, mass transfer rate is enhanced by pulse modulation. In the conditions studied, the adsorption equilibrium constant decreases with increasing ultrasonic power, while the overall mass-transfer coefficient increases. With increasing pulse duty ratio, adsorption equilibrium constant decreases initially, reaches a minimum when pulse duty ratio is 0.5, and then increases. On the contrary, the overall mass-transfer coefficient increases initially and reaches a maximum when pulse ratio is 0.5, and then decreases. Effects of pulse period on adsorption equilibrium and mass transfer rate reached the peak at pulse period of 28.6 ms.
    Mass Transfer Enhancement of Gas Absorption by Adding the Dispersed Organic Phases
    ZHANG Zhigang, XU Tianxing, LI Wenxiu, JI Zhiling, XU Guangrong
    2011, 19(6):  1066-1068. 
    Abstract ( )   PDF (207KB) ( )  
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    Mass transfer enhancement of gas absorption by adding a dispersed organic phase has been studied in this work. Various dispersed organic phases (heptanol, octanol, isoamyl alcohol, heptane, octane, and isooctane) were tested respectively in the experiment. According to the theoretical model and experimental data, the overall volumetric mass transfer coefficient and enhancement factor were obtained under different dispersed organic phase volume fraction and stirring speed. The experimental results indicate that gas-liquid mass transfer is enhanced at different level by adding a dispersed organic phase. The best performance of enhancement were achieved with the dispersed organic phase volumetric fraction of 5% and under an intermediate stirring speed of 670 r·min-1. Among the organic phases tested in the experiment, alcohols show better performance, which gave 20% higher enhancement of overall volumetric mass transfer coefficient than adding alkanes.
    Experimental Study of Heat Transfer Enhancement and Friction Loss Induced by Inserted Rotor-assembled Strand (II) Lubricant Oil 22
    HAN Chonggang, YANG Weimin, DING Yumei, GUAN Changfeng, LI Fengxiang, ZHANG Zhen, YAN Hua
    2011, 19(6):  1069-1074. 
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    The paper described experimental investigation of heat transfer and single-phase pressure drop through tubes with different rotor-assembled strands inserted in the Reynolds number range of 800-9000 with lubricant as working fluid. In the experiment, fixed mounts were employed to eliminate the entrance effect. The experimental results showed that the employment of fixed mounts led to a visible bias of friction factor in the laminar regime while it could not affect the Nusselt numbers significantly. Experiment for the tube inserted with rotors-assembled strand showed remarkable improvement for heat transfer with the Nusselt number increased by 200%-225% in the laminar regime and 125%-160% in the transitional regime. Meanwhile, the friction factor increased inevitably by 200%-300% within the same range of Reynolds number. The comparison of different rotor-assembled strands inserted tubes and plain tube showed that the heat transfer benefited from the increase of the diameter of rotor-assembled strand with the same lead and the decrease of the lead of rotor-assembled strand, so does the friction factor. Based on experimental data and thorough multivariant linear normal regression method, the correlations of average Nusselt number and friction factor are established.