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Table of Content

    30 October 2010, Volume 30 Issue 5 Previous Issue    Next Issue
    研究报告
    Influence of Pore Structure on the Electrochemical Performance of High-specific-surface-area Bamboo Char-based Activated Carbon
    ZHANG Dong-sheng;DENG Cong-jing;XIA Xiao-hong;LIU Hong-bo;HE Yue-de
    2010, 30 (5):  25-30. 
    Abstract ( 614 )   PDF (1175KB) ( 574 )   Save
    High-specific-surface-area activated carbon (HSAAC) was prepared from bamboo char by activation with KOH. The specific surface area and pore structure of activated carbon were characterized by nitrogen adsorption isotherm at 77 K. The specific surface area, mesopore volume and total pore volume increased with the ratio of KOH to carbon. The iodine and methylene blue adsorption values of the HSAAC increased with the increased ratio of KOH to carbon at first and then decreased, at the ratio value of 4, the values reached the maximum, or 2 168 and 569 mg/g respectively. Moreover the performance in charge and discharge of electric double-layer capacitor EDLC using HSAAC as electrodes and relation between specific capacitance and different factors were discussed. The results show that HSAAC sample from the ratio of KOH to carbon of 4 presented a high specific surface area (2610 m2/g) and total pore volume (1.24 cm3/g) and its specific capacitance reached 206 F/g in 30% H2SO4 aqueous electrolytes.
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    Synthesis of A Complex Dimeric Acid by Diels-Alder Reaction between Industrial Fatty Acid and Rosin
    YANG Xiao-hua;XIA Jian-ling;HUANG Kun;ZHANG Yan
    2010, 30 (5):  31-34. 
    Abstract ( 621 )   PDF (660KB) ( 607 )   Save
    A complex dimeric acid was synthesized by Diels-Alder reaction using industrial fatty acid and rosin as raw material. The contents of monomer, dimer and trimer were detected by gel permeation chromatography(GPC). Effects of different reaction conditions on the composition and properties of product were discussed. The result showed that using the amount of the self-made catalyst 1% in terms of mass of the system, mass fraction of rosin 5%, reaction time 5 h, reaction temperature 240℃ and reaction pressure 0.5 MPa, 51.03% mass fraction of dimeric acid can be obtained in the product. The viscosity of product is 320 mPa·s at 40℃ and the acid value of the product is 193.9 mg/g. The product was characterized by 1H NMR, which showed that addition reaction had taken place.
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    Study on Relationship between Foamability and Deinking Effect of Neutral Deinking Agents
    YANG Yang;CAO Yun-feng;LIU Zhu-lan;LU Hai-feng;WANG Yan-li;WEI Li
    2010, 30 (5):  51-56. 
    Abstract ( 616 )   PDF (847KB) ( 627 )   Save
    Mixed office waste paper(MOW) were deinked under neutral condition to investigate the relationship between deinking effect and foamability of deinking agents.The result showed that, among single-component deinking agents, the deinking effect becomes worse with the increased foamability of anionic surfactants and the effect becomes better with the increased foam stability of surfactant. Brightness of deinked pulp treated by the best foamability surfactant AEC-7-Na is only 80.51%(ISO), while brightness of that treated by the best foam stability surfactant ABS is 83.04%(ISO). For nonionic surfactants, there is no obvious relationship between deinking effect and foamability,also foam stability has no effect on deinking effect. It is proofed in the experiment of blended nonionic and anionic surfactants, that the relationship between deinking effect and foamability is uncertain. The main factors which decide the deinking effect are the collecting ability of nonionic surfactants and the blendability of two kinds of surfactants. In this experiment, several blended groups of neutral deinking combination with outstanding deinking effect,such as(the mass ratio 1:1): T-80+SAS, AEO20+AES, AEO12+AEC-7-Na, S-80+AES, have been obtained.
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    Research on Isolation of 2α-Hydroxy-oleanolic Acid and 2α-Hydroxy-ursolic Acid and Their EI-MS(+)Differences
    Lü Yang;XU Shu-wen;CAI Ling;ZHOU Bin;CHEN Long-sheng;
    2010, 30 (5):  91-94. 
    Abstract ( 761 )   PDF (806KB) ( 636 )   Save
    2α-Hydroxy-oleanolic acid and 2α-hydroxy-ursolic acid were isolated from Eriobotrya japonica leaves by preparative reversed-phase high performance liquid chromatography. The structure was confirmed by using UV, EI-MS, NMR and IR. The possitive ion fragmentation pathway was researched by electron ionization mass spectrometry and the stability of ion fragmentation was compared. 2α-Hydroxy-oleanolic acid and 2α-hydroxy-ursolic acid were discerned by comparing the abundance of m/z 248, 203 and 133.
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    Analysis of Volatile Components in Pu-er Tea by SPME-GC-MS
    LUO Fa-mei;ZHAN Jia-fen;LUO Zheng-gang;JIANG Dong-hua;DU Ping;JIANG Jing;ZHANG Xian-jun;
    2010, 30 (5):  95-98. 
    Abstract ( 853 )   PDF (668KB) ( 701 )   Save
    Volatile components from two kinds of Pu-er tea, namely raw tea and ripe tea by two different fermentation processes were extracted by solid phase micro-extraction(SPME) and qualitatively analyzed by gas chromatography/mass spectrometry(GC-MS). The result showed that 60 volatile compounds were identified from two kinds of Pu-er tea, including 44 from raw tea and 43 from ripe tea and 27 from both of them. The main volatile compounds of raw tea were 1,2,3-trimethoxybenzene, epoxylinalol, veratrol, linalool oxide, β-linalool, α-terpineol,etc. The main volatile compounds of ripe tea were 5-methyl-2-hexaone, tetrahydrolinalool, linalool oxide, β-linalool, iso-butyl ether, α-terpineol, etc. There are significant differences among component and content in raw tea and ripe tea on account of fermentation difference.
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    Research Progress of Lignin Model Compounds
    NIE Ming-cai;HUO Shu-ping;KONG Zhen-wu
    2010, 30 (5):  115-121. 
    Abstract ( 1100 )   PDF (1300KB) ( 1204 )   Save
    The common lignin model compounds such as simple phenolic, non-phenolic, α-O-4, β-O-4, β-1, β-5 and 5-5 types, stilbenes and dehydrogenation polymer(DHP) were reviewed in terms of their applications in lignin degradation, modification and chemical structure characterization. Lignin model compounds have determinate structure and properties, which resulted in a wide range of application in the study of lignin, and provide theoretical basis for the analysis of the chemical structure and behavior of lignin.
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    Study on Extraction and Isolation of Tannin from Pine Needles of Pinus elliottii Engelm.
    LI Sen-lin;ZHANG Jian-bin;ZHANG Zheng-fu;WEI Xiong-hui
    2010, 30 (5):  99-102. 
    Abstract ( 838 )   PDF (950KB) ( 554 )   Save
    Process of extracting tannin from pine needles of Pinus elliottii Engelm. was studied. Five main factors were studied on the yield of pine needle extract and tannin. By single factor experiments,the optimal parameters were confirmed as follows: extracting time 5 h at 120℃ with ratio of liquid to solid 14:1(mL:g), and pH value 10. The yield of extract was 17.69% and tannin was 29.17% in the extract. Gallic acid and other compositions can be well separated by HPLC technique. The experiment proved that extracts may contain hydrolysable tannin or complex tannins.
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    Application of Subcritical Water Extraction in the Field of Plant Extractives
    ZHENG Guang-yao;BO Cai-ying;ZHANG Jing-li
    2010, 30 (5):  108-114. 
    Abstract ( 862 )   PDF (1197KB) ( 1018 )   Save
    Subcritical water extraction is a new kind of separation technology. The principle and advantage of subcritical water extraction are described, the application of extraction of valuable compounds(such as volatile oil, polyphenols, pectine, lactone, anthraquinone,etc.)from natural plants and food by-products are introduced, and the development prospect of subcritical water extraction in the field of plant extractives is explored.
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    Study on Adsorption Properties of Modified Activated Carbon on NH3
    SHENG Li-li;TANG Ying;YIN Wei-neng;LU Zheng-zheng;CUI Qun;CHEN Hai-jun;WANG Hai-yan;YAO Hu-qing
    2010, 30 (5):  35-39. 
    Abstract ( 834 )   PDF (830KB) ( 899 )   Save
    Modification of activated carbon could increase the content of surface acid functional groups and NH3 adsorption capacity, which would strengthen adsorption refrigeration process using activated carbon-NH3 working pairs. Modification reagents were screened out. The effects of modification conditions on the content of superficial groups were investigated. Superficial microstructure of modified activated carbon was analyzed by FT-IR and SEM. Adsorption capacity of NH3 on activated carbon was measured. The results show that nitric acid modification can obviously increase surface acid functional groups of activated carbon. The feasible modification conditions are: concentration of nitric acid 4 mol/L, temperature 20℃, modification time 12 h. Compared to the original sample, the acidic functional groups content of activated carbon increased 3.5 times, adsorption capacity for NH3 increased 36.98% while iodine value decreased 9.20% after nitric acid modification.
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    Research Progress on Extraction and Purification of Carsonic Acid
    LI Da-wei;BI Liang-wu;ZHAO Zhen-dong
    2010, 30 (5):  122-126. 
    Abstract ( 665 )   PDF (867KB) ( 975 )   Save
    Different extraction methods including traditional solvent extraction, homogenated extraction, ultrasound-assisted extraction, supercritical carbon dioxide extraction, etc. for the extraction of carsonic acid were reviewed. Different purification methods of carnosic acid were also introduced.
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    Study on Synthesis of Sucrose Esters from Bio-diesel
    WANG Kui;JIANG Jian-chun;LI Xiang-yu;WU Huan;LI Ke
    2010, 30 (5):  1-4. 
    Abstract ( 664 )   PDF (812KB) ( 722 )   Save
    Using sucrose and bio-diesel as raw materials, the condition of sucrose esters (SE) synthesis with solventless method was optimized. The optimum conditions of SE synthesis at 130℃ for 3 h with the mole ratio of bio-diesel to sucrose 1:1-4:1 were obtained by using 2% potassium carbonate as catalyst and 10% potassium stearate as co-solvent under vacuum less than 0.09 MPa. Mixed solvent extraction was used to purify raw product to obtain high-qualified sucrose esters of bio-diesel. The yield can reach 78%.
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    Preparation and Properties of Bamboo-based Activated Carbon with High Specific Surface Area
    CUI Dan-dan;JIANG Jian-chun;SUN Kang;LU Xin-cheng
    2010, 30 (5):  57-60. 
    Abstract ( 772 )   PDF (892KB) ( 1091 )   Save
    Activated carbon was prepared from bamboo origin by phosphoric acid activation. The effects of different factors such as impregnation ratio, activation temperature, activation time, heating rate on adsorption properties of bamboo activated carbon were studied. The high adsorption capacity of bamboo-based activated carbon with methylene blue adsorption capacity upto 200 mL/g, caramel decolorization rate upto 120% was obtained. Results showing the optimum conditions are: impregnation ratio 3:1(g:g), activation temperature 400℃, heating rate 10℃/min and activation time 40 min. The bamboo-based activated carbons were characterized by SEM and N2 adsorption analysis, indicating that the bamboo-based activated carbon has high BET surface area (2103 m2/g) and developed pore structure.
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    Preparation of Shellac-wax Emulsion by Nonionic Surfactant
    LI Kai;ZHOU Mei-cun;ZHANG Hong;ZHENG Hua
    2010, 30 (5):  69-75. 
    Abstract ( 749 )   PDF (1278KB) ( 691 )   Save
    Shellac-wax emulsion was prepared by inverse phase method. Through single factor experiment to choose factors and levels, volume average particle diameter of the emulsion was optimized through response surface methodology with three factors and three levels based on principle of Box-Behnken design. The results showed that the optimum conditions were as follows: emulsifier dosage 5 g, rate of mixing 500 r/min, emulsifying temperature 88℃. Under the optimal conditions, the optimum volume-average particle size was 0.39 um. The particle size and distribution of the optimized shellac-wax emulsion were studied with laser granularity analyzer. The stability of the shellac-wax emulsion was tested by freezing-thawing experiment. The particle diameter of shellac-wax emulsion is well-distributed below 0.76 μm, and the emulsion possesses good freezing-thawing stability.
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    Study on Corrosion Inhibition Performance of Phyllostachys sulphurea Leaves Extract
    DENG Shu-duan;LI Xiang-hong;FU Hui
    2010, 30 (5):  81-86. 
    Abstract ( 635 )   PDF (1311KB) ( 803 )   Save
    The main functional groups of Phyllostachys sulphurea(Carr.)Riviere leaves extract(PSLE) were characterized by Fourier transform infrared (FT-IR) spectroscopy. The inhibition effect of PSLE on the cold-rolled steel (CRS) in 1.0 mol/L HCl solution at 20℃ was studied by methods of weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy(EIS)and atomic force microscopy(AFM). Meanwhile, the inhibitive mechanism was proposed from the adsorption viewpoint. The results show that PSLE is a good corrosion inhibitor, and maximum inhibition efficiency is up to 94.2% at concentration 100 mg/L. PSLE exhibits its inhibitive performance via adsorption of functional groups containing N and O atoms on steel surface, and the adsorption of PSLE on CRS surface obeys Langmuir adsorption isotherm. Polarization curves reveal that PSLE behaves as a mixed-type corrosion inhibitor. EIS spectra exhibit one capacitive loop and charge transfer resistance value increases with the increase of inhibitor mass concentration(c). AFM results reveal that PSLE can be adsorbed on steel surface to form a dense protective film.
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    Enthalpy-entropy Compensation of the Gemini Surfactant CsH2s-α,ω-bis (dehydroabietyl-hydroxypropylteteramethylethylammonium Chloride)
    LI Hai-chao;HU Xu
    2010, 30 (5):  65-68. 
    Abstract ( 657 )   PDF (680KB) ( 566 )   Save
    To study the relationship between the "tail" structure and the behavior of Gemini surfactants in aqueous solution, the thermodynamic parameters of micellization of a new Gemini surfactant CsH2s-α,ω-bis(dehydroabietylhydroxypropylteteramethylethylammonium chloride), with dehydrogenated rosin as hydrophobic "tails" in the structure were investigated. When enthalpy of interaction(ΔH) was plotted against entropy(ΔS),linear plots were obtained. This indicates the clear enthalpy-entropy compensation with a compensation temperature of approximately 310.8 K.
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    综述评论
    Review of Refining Methods in Production of Diesel-like Fuel from Biomass
    XU Jun-ming;JIANG Jian-chun;CHEN Jie;
    2010, 30 (5):  103-107. 
    Abstract ( 658 )   PDF (952KB) ( 683 )   Save
    The research advances in the main methods for biofuel production including enzymatic catalysis, catalytic cracking and catalytic hydroprocessing are introduced. It is pointed out that enzymatic catalysis is an environment-friendly method to produce bio-diesel with great industry prospect. Compared with enzymatic catalysis, catalytic cracking and catalytic hydroprocessing process generate fuels that have physical and chemical properties comparable to those specified for petroleum-based fuels. At last the existing main problem were mentioned and prospect of this research field is pointed out.
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    研究报告
    Study on Cyanoethylation of Microcrystalline Cellulose and Its Reaction Kinetics
    QU Bao-xue;QIN Te-fu;LI Yan;CHU Fu-xiang
    2010, 30 (5):  5-11. 
    Abstract ( 670 )   PDF (1335KB) ( 554 )   Save
    Microcrystalline cellulose was cyanoethylated by using acrylonitrile as etherifying agent. Effects of reaction time and reaction temperature on degree of substitution (DS) of the product were studied. It was indicated that DS of microcrystalline cellulose increases with prolonging of reaction time or increment of reaction temperature under 50℃. The peak of hydroxyl group of the cyanoethylated microcrystalline cellulose obviously became weaker and shaped cyano absorption peak was observed by FT-IR. It was concluded that part of hydrogens of hydroxyl group were substituted by cyanoethyls. X-Ray diffration pattern showed that the original crystal structure of microcrystalline cellulose was broken. With increase of DS of cyanoethylated microcrystalline cellulose, thermoplasticity increased before DS reach 1.43, then receded with increase of DS, as shown by X4 microscopic melting-point and Vicat softening-point measurements. It was concluded in this study that the rate constant of cyanoethylation of microcrystalline cellulose was ordered by 1.30,1.61,1.94 and 2.26 s-1 under reaction temperature of 30,35,40 and 45℃ respectively. Activation energy of cellulose cyanoethylation was 29.8 kJ/mol.
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    Simulation of Supercritical CO2 Extraction for Camellia Seed Oil by Back Propagation Neural Network
    LU Ze-xiang;FAN Li-wei;ZHENG De-yong;LIAO Yi-qiang;HUANG Biao
    2010, 30 (5):  12-18. 
    Abstract ( 581 )   PDF (1051KB) ( 572 )   Save
    Back propagation neural network (BPNN) was applied to simulate and predict the extraction of camellia seed oil by supercritical CO2. Neural network's structure, training and optimization of learning algorithms and hidden layer structure were investigated. Under different conditions of feed particle's mean diameter (0.215-0.625 mm), pressure (30-35 MPa), temperature (35-50℃) and CO2 flowrate (20-25 L/h), the yields of camellia seed oil were predicted by BPNN. The results show that L-M algorithm is the optimum learning algorithm of the BPNN, and the BPNN with 5/8/1 network structure has good simulating performance. The model predictions are in good agreement with the experimental data, and relative errors among most of the predictions and the corresponding experimental data are less than 3.0%. The BPNN developed can be used in simulation of this process.
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    Analysis on Chemical Components of Essential Oil of Chinese Sweetgum Resin
    SONG Xiao;ZENG Tao
    2010, 30 (5):  40-44. 
    Abstract ( 785 )   PDF (874KB) ( 771 )   Save
    Essential oil of Chinese sweetgum (Liquidambar formosana Hance) resins from Jiangxi, Guangxi and Guizhou provinces of China were obtained through steam distillation. The chemical components of essential oil were analyzed by GC-MS.Twenty-three compounds were separated and identified. There are 9 kinds of monoterpinenes, 9 kinds of sesquiterpinenes and 5 kinds of other components. The chemical components and contents of monoterpinenes were similar. Pinenes contents were all as high as 40% to 55%, but chemical components and contents of sesquiterpinenes were different. The content of β-caryophyllene and caryophyllene oxide in the essential oil from Guizhou Province was as high as 30%.
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    Synthesis and Characterization of Pinic Acid Diacyl-didehydroabietyl-bis-oxadiazole
    CHEN Li;CEN Bo;DUAN Wen-gui;DONG Shu-qiu
    2010, 30 (5):  61-64. 
    Abstract ( 645 )   PDF (770KB) ( 748 )   Save
    Dehydroabietic acid chloride was prepared from dehydroabietic acid which was isolated and purified from disproportionated rosin. Pinic acid dihydrazide was synthesized using α-pinene as raw material via pinonic acid, pinic acid and pinic acid diethyl esters. Pinic acid dihydrazide could readily react with dehydroabietic acid chloride under phase transfer catalysis to afford N,N'-didehydroabietyl pinic acid dihydrazide. Pinic acid diacyl-didehydroabietyl-bis-oxadiazole was synthesized by cyclization of N,N'-didehydroabietyl pinic acid dihydrazide with POCl3. The synthetic conditions were studied and the target compound was characterized by elemental analysis, IR, MS, 1H NMR and 13C NMR.
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    Lignin Distribution in Cell Wall of Bamboo Culms (Phyllostachys pubescens and Pseudosasa amabilis)
    YANG Shu-min;REN Hai-qing;FEI Ben-hua;JIANG Ze-hui
    2010, 30 (5):  19-24. 
    Abstract ( 814 )   PDF (1125KB) ( 780 )   Save
    Lignin distribution in different anatomical regions of 12-month-old bamboo species, namely moso bamboo and Pseudosasa amabilis Keng f. was investigated. Lignification was studied by means of optical microscopy and confocal laser scanning microscopy. In addition, distribution of lignin in different tissues (fibre, parenchyma and vessel) was investigated by visible-light microspectrophotometry coupled with Wiesner and M?ule reaction. Lignin is widely distributed in different tissues, in which there is lignin content difference among tissues and anatomical regions. Guaiacyl lignin units and syringyl lignin units can be found in cell wall of fibre, parenchyma and vessel. There is no regular variation in lignin content along different radial location of culms and different location in fibre strands. The multilayer of the fibre secondary cell wall has alternating thick and thin layers, while lignin content of thin layer is higher than that of thick layers.
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    Study on the Rheological Property of Fluorin-silicon Resin/Urushiol Composite
    LI Yang-jun;SHAO Hui-ju;XU Guo-min
    2010, 30 (5):  87-90. 
    Abstract ( 541 )   PDF (1138KB) ( 510 )   Save
    The rheological property of fluorin-silicon resin/urushiol composite system was studied. The rheological behavior, rheologial style, thixotropy and structure-resume velocity of the composite with different proportion were examined. The results indicated that all n values of the composite are less than 1, belonging to a pseudoplastic fluid. The composite also is a thixotropic fluid, its viscosity is related to shearing time, and the viscosity decreased with the increase of shearing time under constant shearing speed of 80 s-1, showing its appropriate thixotropy and structure-resume speed which are beneficial to control the appearance and performance of coatings.
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    Effects of Enzyme-treatment on Beatability of Mixed Poplar P-RC APMP
    YANG Gui-hua;MU Yong-sheng;CHEN Jia-chuan;ZHANG Feng-shan
    2010, 30 (5):  45-50. 
    Abstract ( 610 )   PDF (1041KB) ( 717 )   Save
    The effects of cellulase and xylanase treatment on beatability of mixed poplar P-RC APMP pulp were studied. The results showed that, compared with the pulp untreated by enzyme, the beatability of pulp treated by enzyme was improved, such as an increase of 1.0- 6.5 °SR in beating degree and a decrease of 10%-25% in beating energy consumption at the same beating degree. Breaking length, tearing index, bursting index and folding endurance of the pulp treated by cellulase were respectively improved by 18%,14%,16% and 100% at the same PFI revolution. Brightness of the pulp treated by xylanase was increased by 1.7 percent ISO,and physical strengths of the treated pulp were slightly improved.Effect of cellulase-treatment is better than that of xylanase-treatment in improvement of beatability, decreasing of beating energy consumption and intensification of physical strength. Effects of xylanase-treatment is better than that of cellulase-treatment in optical properties of pulp, such as improvement of brightness. Treated by enzyme,fiber structure was turned loose and limp, leading to strengthen the crosslinking among fibers.
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    Response Surface Methodology for Xylose Production from Corncob Pretreated by Steam Explosion
    WANG Dong-mei;LIU Gui-yan;LI Chun;DAI Da-zhang
    2010, 30 (5):  76-80. 
    Abstract ( 653 )   PDF (1074KB) ( 620 )   Save
    Corncob pretreated by steam explosion was used as the substrate of xylanase for the preparation of xylose by enzymatic degradation, and the hydrolysis process was optimized by response surface methodologies (RSMs). According to the results of single factor experiment, five parameters which had great influence on the yield of xylose were selected for 53 full factorial experiment designed by Box-Benhnken central composite method. The obtained optimum conditions of enzymatic hydrolysis of corncob pretreated by steam explosion were:xylanase amount 13.05 U/g(based on corncob), water-feed ratio 13.2:1(mL:g), enzymatic time 5 h, temperature 47.3℃, pH value 5.84. Under the optimum conditions, the yield of xylose reached upto 83.24%.
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