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    30 December 2007, Volume 27 Issue 6 Previous Issue    Next Issue
    研究报告
    Study on Purification and Some Properties of A Highly Glucose-tolerant Extracellular β-Glucosidase from Aspergillus niger
    ZHAO Lin-guo;YOU Li-jin;MENG Peng;YU Shi-yuan
    2007, 27 (6):  41-46. 
    Abstract ( 563 )   PDF (1151KB) ( 712 )   Save
    Two kind of extracellular β-glucosidases were purified to homogeneity from an Aspergillus niger by ammonium sulfate precipitation, Phenyl Sepharose CL-4B hydrophobic interaction chromatography, DEAE-Sepharose ion exchange chromatography and Sephacryl S-200 HR gel layer chromatography. One of them was a highly glucose-tolerant novel β-glucosidase with a Ki of 41.01 mmol/L, and the final purification factor 56.7 times and 22.66% yield were obtained. The enzyme single subunit mole-cular weight was about 114.6 ku which was identified by SDS-PAGE. The Km and vmax values of the enzyme were 0.904 mmol/L and 1.08 μmol/min, respectively, using p-nitrophenyl-β-D-glucopyranoside(pNPG) as a substrate. The optimum reaction temperature and pH value for β-glucosidase were 60℃ and pH value 4.0, respectively. The enzyme was stable in the pH value range of 3.0-7.0 and up to 60℃. The enzyme was greatly inhibited by Ag+. Other metal ions tested and EDTA hand no effects on the activity of β-glucosidase. Different organic solvent had different effects on the activity of β-glucosidase, methanol and 1-butanol enhanced the activity, whereas acetone and acetonitrile inhibited the activity obviously.
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    Synthesis and Structure Characterization of Polyols from Hydrogenated Terpinene-maleic Ester Type Epoxy Resin
    WU Guo-min;KONG Zhen-wu;HUANG Huan;CHEN Jian;CHU Fu-xiang
    2007, 27 (6):  17-21. 
    Abstract ( 505 )   PDF (955KB) ( 492 )   Save
    Three kinds of polyols were synthesized from hydrogenated terpinene-maleic ester type epoxy resin(HTME)and secondary amines(diethanolamine(DEA), N-methylethanolamine(MEA) and diethylamine(DeA)). They can be used in place of the commonly used polyols to prepare two-component polyurethanes.When reacted at 60-70℃ for about 2 h, products of good quality can be obtained by using ethanol as solvent in an amount about 40% by weight based on the weight of reactants. Among the polyols synthesized under the optimum conditions, HTME-D-EA polyol has the largest hydroxyl value of(300±20)mg/g, HTME-MEA polyol has a value of(260±20)mg/g, and HTME-D-eA polyol has the smallest hydroxyl value of(200±10)mg/g. Because of the low chemical activity of DeA reacting with oxirane ring of HTME, the residual epoxy value of HTME-D-eA polyol is comparatively large, in contrast with those of other two polyols. The chemical structures of the polyols from HTME were characterized by chemical and FT-IR spectrometric methods.
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    Study on Curie-point Pyrolysis of Bamboo
    LIN Mu-sen;JIANG Jian-chun
    2007, 27 (6):  27-30. 
    Abstract ( 440 )   PDF (774KB) ( 611 )   Save
    Bamboo is pyrolyzed at 358,445,590 and 670℃ in JHP-5 model Curie-point pyrolysis. The results of GC-MS on-line analysis show that the main liquid products are furfural and aromatic substances. The relative content of 2,3-dihydrobenzofuran comes up to 21% at 445℃, and the relative contents of main liquid products climb up then decline as the pyrolysis temperature increasing. The temperature between 445℃ to 590℃ is fit for liquid products in this experimental condition. Pyrolysis mechanism indicates that furfural and aromatic substances are formed from the pyrolysis of cellulose, hemicellulose and lignin, respectively.
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    Property Comparison of Cationic Rosin Emusions between Tertiary Amine Type and Quaternary Ammonium Type
    WU Zong-hua;CHEN Shao-ping;WENG Jing-zheng;LIU Hui-gui
    2007, 27 (6):  31-35. 
    Abstract ( 700 )   PDF (936KB) ( 550 )   Save
    Cationic rosin emulsions with tertiary amino groups(SYM-1) and with quaternary ammonium groups(JYM-1) respectively were prepared from rosin and copolymers of styrene, acrylic ester and dimethylamino ethyl methacrylate or dimethyldiallyl ammonium chloride as emulsifying agents, and their sizing performances were compared. The results showed that the electric charge density of the polymeric surfactant with tertiary amino groups(SYS-1) and the sizing performance of SYM-1 were influenced greatly by changes of pH value. The sizing degree of SYM-1 was 10 s larger than that of JYM-1 under the same condition, but SYM-1 lost its sizing performance in the papermaking system containing 10% of CaCO3. The electric charge density of the cationic polymeric surfactant with quaternary ammonium group(JYS-1) did not change with the increase of pH value from 1 to 11. The sizing degree of JYM-1 was larger than 5 s in the system containing CaCO3 when the complex of alum and polyvinylamine was used as anchor agent.
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    Study on Extraction and Purification of Betulin from Birch Bark
    WANG Shi-fa;ZHANG Ming-guang;LI Yan-ping
    2007, 27 (6):  22-26. 
    Abstract ( 764 )   PDF (771KB) ( 829 )   Save
    The technological conditions for extraction and purification of betulin from the outer bark of white birch were investigated. The suitable extraction conditions were determined as follows: amount of bark 30 g, the size of bark particle 0.42-1.16 mm, chloroform was used as extraction solvent, extraction time 7 h. The yield of light-yellow crude extract obtained under aforesaid conditions reached 38.5%. Betulin with high purity was obtained by recrystallization, and the suitable recrystallization conditions were determined as follows: isopropanol was a suitable solvent for recrystallization of betulin, and the ratio of crude extract/isopropanol was 1:20(g:mL); crystallization temperature -5℃, crystallization time 1 h. The yield of betulin was 41.4%, melting point was 245-254℃, and purity was 95.4%.
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    Composition and Antimicrobial Activity of Essential Oil from Foeniculum vulgare Mill. Seeds
    ZHONG Rui-min;XIAO Zi-jun;ZHANG Zhen-ming;LIU Jian-nan;WANG Yu-mei
    2007, 27 (6):  36-40. 
    Abstract ( 764 )   PDF (1146KB) ( 925 )   Save
    The study was carried out to investigate the chemical composition and antimicrobial activity of the hydrodistilled essential oil from Foeniculum vulgare Mill. seeds. The chemical composition of the oil could be identified satisfactorily by GC-MS analyses as well as comparison of the Kovats retention indices(KI) of elution peaks with literature data. The essential oil of F. vulgare seeds is dominated with trans-anethole(70.78%), estragole(7.78%), fenchone(5.87%), limonene(5.85%) and δ-3-carene(2.01%). The antimicrobial test results show that this essential oil has significant broad spectrum of antimicrobial activity against all 7 food-borne pathogens and 2 spoilage fungi tested. Especially, Apergillus niger ATCC 16404 and Vibrio ahaemdyticus VPL 4-90 are most sensitive to it, the minimum inhibitory concentration(MIC) values of them are less than 0.004% and 0.015%(volume fraction), respectively.
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    Study on Disproportionation of Resin Acid Catalysed by Nano-Ni(Ⅱ)——Study on Disproportionation of Resin Acid
    HUANG Li;XIE Hui;YANG Cheng-wu
    2007, 27 (6):  47-50. 
    Abstract ( 466 )   PDF (841KB) ( 486 )   Save
    Nano-Ni was first used as catalyst for disproportionation of resin acid. The main factors affecting disproportionation of abietic acid were investigated, such as stirring rate, the category and quantity of catalysts, temperature, quantity of solvent, etc. The optimum conditions for disproportionation of abietic acid over nano-Ni were determined as follows: stirring rate 300 r/min, reaction temperature 160℃,dosage of catalyst 2.0% of abietic acid, 200# solvent oil 50%(weight) and reaction time 3 h.
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    Study on Hydrogenation of Rosin Catalyzed by Mesoporous Molecular Sieve MCM-41 Loaded with Nanometer Pd
    LV Xian-fu;YU Shi-tao;LI Lu;LIU Fu-sheng;XIE Cong-xia
    2007, 27 (6):  51-55. 
    Abstract ( 540 )   PDF (922KB) ( 657 )   Save
    Nanometer metal particle Pd was loaded into the holes of the mesoporous molecular sieve MCM-41 by impregnation. Pd/MCM-41 mesoporous molecular sieve is characterized by means of XRD and TEM. The results indicate that nanometer metal particle Pd was uniformly loaded into mesoporous sieve successfully, and the mesoporous sieve still keeps its mesoporous characters. The Pd/MCM-41 catalyst has better catalytic activity and selectivity than Ni/MCM-41 and Pd/C. Factors affecting hydrogenation of rosin such as reaction time, temperature, hydrogen pressure and the dosage of catalyst were studied, and the components were analyzed with gas chromatography. The results showed that the optimum reaction condition is: mass ratio of rosin to catalyst 1:0.04(rosin 5 g, catalyst 0.2 g) reaction temperature 180℃,pressure 8 MPa, reaction time 4 h. Under this condition the content of hydrogenated part in the product is 89.7%,which proved that this mesoporous molecular sieve Pd/MCM-41 has good activity.
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    A New Triterpene from Celastrus hypoleucus Root
    WANG Hong;MEI Jian-feng;YI Yu;CHEN Jian-shu;GUO Tao;YING Guo-qing
    2007, 27 (6):  56-58. 
    Abstract ( 511 )   PDF (292KB) ( 551 )   Save
    The Hleat xib nenb is the root of Celastrus hypoleucus(Oliv.)Warb.ex Loes., widely distributed in China, has been used in the treatment of inflammation and detumescence. Six compounds(1-6) were isolated from the roots of H. xib nenb. Among them compound 1 is a novel compound. Its structure was characterized and identified by spectral method(especially by 2D NMR) to be 29-methoxyfriedelan-3-one.
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    Cloning and Sequence Analysis of the xyn Ⅰ Encoding Xyn Ⅰ from Aspergillus usamii E001
    WU Min-chen;WANG Shi-liang;ZHOU Chen-yan
    2007, 27 (6):  59-64. 
    Abstract ( 533 )   PDF (933KB) ( 703 )   Save
    The xyn I cDNA(GenBank, DQ302412) was amplified with RT-PCR methods from the total RNA extracted from Aspergillus usamii E001. Sequence analysis showed that the cDNA is 881 bp in length including 5' and 3' non-encoding regions, a 111 bp signal peptide encoding region,and a 567 bp mature peptide encoding region which encoded the xylanase(Xyn I) of 188 amino acids. The xylanase gene(xyn I) DNA(GenBank, DQ302413) was amplified with signal primer PCR methods from the genomic DNA extracted from E001. The DNA is 1098 bp in length which included the regions of a promoter, a intron and two exons. Comparison of the homologies of the amino acid sequence of the Xyn I with other xylanases from GenBank was carried out. The results showed that the Xyn I is a new xylanase and belongs to G/11 family.
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    Technologies of Liquefaction of Bamboo and Preparation of Adhesive
    SUN Feng-wen;LI Xiao-ke
    2007, 27 (6):  65-70. 
    Abstract ( 497 )   PDF (984KB) ( 730 )   Save
    The technology of liquefying processed-waste bamboo with phenol is researched by single factor trial and orthogonal trials; and the preparation technology and properties of the adhesive from this phenol-liquefied bamboo with formaldehyde(BPF) are studied. The results testify that temperature is significant on liquefaction, mass ratio of phenol to bamboo is in the next place, catalyst dosage within the range of 2%-4% is less effective. The optimum conditions of liquefaction are as follows: mass ratio of phenol to bamboo 3.5, catalyst dosage 4%, liquefying temperature 145℃, and liquefying time 60 min. Liquifaction rate of bamboo arrived 99.1%. For the preparation of the adhesive, mass ratio of liquefied bamboo products to formaldehyde(37%) is 100 to 164.8-199.5,while the ratio 100 to 108.2 is the best. This adhesive has a lower curing temperature than that of normal PF resin. At the hot-press temperature of 130℃ or 140℃, this new adhesive can provide excellent bond strength of the plywood, and the favorable temperature is 140℃.
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    Influence of White-rot Fungi Pretreatment of Corncobs on Vapor-hydrolysis with Propionic Acid to Prepare Cellulose
    ZHAO Hua;DING Juan
    2007, 27 (6):  71-76. 
    Abstract ( 492 )   PDF (1137KB) ( 508 )   Save
    The influence of white-rot fungi pretreatment of corncob on vapor-hydrolysis with propionic acid to make cellulose was studied. The results showed that manganese peroxidase(MnP), lignin peroxidase(LiP), laccase, xylanase and cellulase treatments reached their biggest enzyme activities during the bio-treatment processing of corncob after 5, 6, 7, 15 and 10 d respectively, which were 1.326, 10.25, 0.0627, 0.33 and 403 U/g, respectively. The optimized conditions of vapor-hydrolysis with propionic acid on corncob using response surface methodology were as follows: ratio of solid to liquid 1:10(g:mL), 70 min, concentration of propionic acid 900 g/L, the content of cellulose reached 91.09% of the product. After bio-treatment for 10 d, content and retention rate of cellulose were 97.12% and 94.70%, respectively, while contents of hemicellulose and lignin were 0.96% and 0.92%, respectively.
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    Hydration of α-Pinene over the Composite Catalytic System of Sulfonic Alkylimidazole Phosphate-chloroacetic Acid
    JI Kai-hui;LIU Shi-wei;YU Shi-tao;LIU Fu-sheng;XIE Cong-xia
    2007, 27 (6):  77-80. 
    Abstract ( 566 )   PDF (656KB) ( 683 )   Save
    An acidic functional ionic liquid 1-(3-sulfonic group)propyl-3-methylimidazole dihydro-phosphate((HSO3-pmim)H2PO4) was prepared and characterized by FT-IR, 1H NMR and 13C NMR. Hydration of α-pinene was studied over the composite catalytic system of sulfonic alkylimidazole phosphate-chloroacetic acid((HSO3-pmim)H2PO4-ClCH2COOH). The optimum conditions for hydration of α-pinene were obtained as follows: n(α-pinene):n((HSO3-pmim)H2PO4):n(chloroactic acid):n(water) 6:1:6:30,reaction temperature 80℃, reaction time 8 h. Under the above conditions, the conversion of α-pinene was 97% and the selectivity of terpineol was 47.1%. The reusability of the composite catalytic system was investigated. Under the optimum conditions, when the composite catalytic system was repeatedly used for 5 times, α-pinene conversion reached 83.7% and the selectivity of terpineol was51.6%. It also can be found that the simple experimental and product-isolation procedure combinated with easy recovery and reusability of the composite catalytic system are expected to contribute to the development of clean and environmentally friendly strategy for the synthesis of α-terpineol.
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    Synthesis and Bioactivity of Sulfodehydroabietates
    HAN Chun-rui;SONG Zhan-qian;LI Hai-tao;YANG Dong-mei
    2007, 27 (6):  81-84. 
    Abstract ( 539 )   PDF (695KB) ( 661 )   Save
    Several sulfodehydroabietates were prepared via sulphonation and salt reaction using dehydroabietic acid directly as raw material. The structures were characterized by IR. One-step salt reaction was studied in detail, especially the effect of pH value of system, which is the critical factor. The optimum pH values of different systems were obtained by simulating reaction and comparing to theoretical pH value of generating precipitation. According to body pH value and toxicity, ferrous iron, cobalt, nickel and manganese salts were selected for synthesizing sulfodehydroabietates, which are resistant to gastric juice activity. The pathology and toxicology of dis-ferrous sulfodehydroabietate were studied. The results showed that the toxicology is very low, the inhibition to gastric secretion and inhibition ratio of total acid by ferrous sulfodehydroabietate at 50, 100, 150 mg/kg doses respectively are better than that of cimitidine at 160 mg/kg dose.
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    Inducing and Screening of Lipase-producing Strain for Biodiesel Fuel Production
    LI Xun;LI Zhi-lin;YANG Yang;WANG Fei;JIANG Jian-chun
    2007, 27 (6):  85-89. 
    Abstract ( 442 )   PDF (907KB) ( 645 )   Save
    In order to improve the lipase activity of the Rhizopus oryzae strain which is used for producing biodiesel fuel, ultraviolet mutation is employed in this research. The hydrolytic lipase activity and synthetic lipase activity of the selected strain R. oryzae LY6 was 433% and 112% as much as that of the original strain, reaching to 4.33 and 0.28 U/mL respectively. The maximum hydrolytic lipase activity of R. oryzae LY6 was at pH value 7.0. The immobilized R. oryzae LY6 as whole cell catalyst was used to catalyze transesterification of soybean oil. When the ratio of methanol to soybean oil is 3:1, the content of methyl ester in biodiesel fuel was 87.3%, which is 41.0% higher than the original one. When the ratio of methanol to soybean oil is 4:1, the content of methyl ester was 96.1%, which is 16.8% higher than the original one.
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    Study on Diels-Alder Reaction between β-Myrcene and Maleic Anhydride Catalyzed by SO42-/TiO2-ZrO2 Solid Superacid
    LUO Jin-yue;AN Xin-nan;LEI Fu-hou
    2007, 27 (6):  90-94. 
    Abstract ( 1859 )   PDF (843KB) ( 1027 )   Save
    Diels-Alder reaction between β-myrcene and maleic anhydride catalyzed by SO42-/TiO2-ZrO2 solid superacid was investigated. By using GC, GC-MS and IR, main product in this reaction is confirmed to be 4-(4-methyl-3-pentenyl)-4-cyclohexene-1,2-dicarboxylic anhydride. The result shows that this catalyst has high catalytic activity and good selectivity to the Diels-Alder reaction between β-myrcene and maleic anhydride. The effects of catalyst to its catalytic activity are investigated. The result also shows that the optimum conditions for the preparation of SO42-/TiO2-ZrO2 catalysts are as follows: n(Ti):n(Zr) 1:1, calcination temperature at 450℃. Under these conditions, the optimum conditions for the Diels-Alder reaction are as follows: n(β-myrcene):n(maleic anhydride) 1:1,reaction time 4 h, reaction temperature 60℃, and the ratio of solid superacids to β-myrcene mass part 1%, the β-myrcene conversion is 96.5%, and the 4-(4-methyl-3-pentenyl)-4-cyclohexene-1,2-dicarboxylic anhydride selectivity is 94.0%, or yield is 90.7%. Furthermore, the effect of storage time of the catalysts on the reaction and the experiments on regeneration of catalysts are carried out.
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    Study on Quantitative Determination of 1,2,3-Trimethoxybenzene
    WU Dong-mei;CHEN Jia-hong;WANG Yong-mei;WU Zai-song
    2007, 27 (6):  95-98. 
    Abstract ( 482 )   PDF (715KB) ( 506 )   Save
    Methods of gas chromatography and UV-spectrophotometry for determination of 1,2,3-trimethoxybenzene content were studied. Test conditions of the methods were proposed. Statistical inspection results showed that the two groups of measuring data determined respectively by GC and UV were in compliance with normal distribution, therefore, both methods are practical. But distinct difference existed in statistical precision between methods of GC and UV, the former was more precise.
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    Comparison of Chemical Constituents of the Essential Oil from Fructus Viticis during Different Harvesting Time
    CHEN Ti-qiang;WU Jin-zhong;YU De-yi;CHEN Li-yan
    2007, 27 (6):  99-104. 
    Abstract ( 688 )   PDF (945KB) ( 692 )   Save
    The effects of different harvesting time under the same habitat on the chemical constituents of essential oil obtained by steam distillation from fructus viticis, which were the dried fruits of Vitex trifolia Linne var. simplicifolia Cham.(synonym:V.rotundifolia Linne fil.), were studied. The essential oil contents were 0.35%, 0.41%, and 0.39% during different harvesting time, namely Aug., Sep. and Oct. respectively. According to the order of the harvesting time, 19, 22 and 29 compounds in the different essential oils were detected by GC-MS, respectively, but only 5 compounds in three different essential oils are in common. The main compounds in all essential oils were terpenoids, whose contents were 99.6%, 90.2% and 94.1%, respectively. This result implies that most of the chemical constituents among three different essential oils were different. On the other hand, the types of three main terpenoids were pinanes, acetoxy-p-menthanes, and p-menthane-diene during the three different harvesting times, respectively. These chemical types have similar structures that will be used for further investigating their interrelation in fructus viticis in order to optimize its quality.
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    Study on Chemical Constituents of Semen Pharbitidis(Ⅱ)
    CHEN Li-na;LI Ping
    2007, 27 (6):  105-108. 
    Abstract ( 682 )   PDF (652KB) ( 760 )   Save
    The active constituents in semen pharbitidis were studied. Seperation and purification were performed on columns of silica gel and Sephadex LH-20, and the chemical structures were elucidated by various spectroscopic data. Eight compounds were isolated from ethyl acetate fraction of 70%(volume fraction) ethanol extract, and identified as cinnamic acid(Ⅰ),ferulic acid(Ⅱ),chlorogenic acid(Ⅲ),methyl chloroformate(Ⅳ),propyl chloroformate(Ⅴ),rhein(Ⅵ),12-hydroxy-methyl abieformate(Ⅶ) and 12-hydroxy-hydromethylabieformate(Ⅷ). These compounds were isolated from the genus Pharbitis for the first time by search.
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    Comparison Study of Different Methods for Extracting Flavonoids from Phyllostachys prominensns(W.Y.Xiong) Leaves
    YUAN Ke;XUE Yue-qin;LOU Lu-huan
    2007, 27 (6):  109-112. 
    Abstract ( 574 )   PDF (776KB) ( 754 )   Save
    Experiments of six different methods for extracting flavonoids from leaves of Phyllostachys prominensns(W.Y.Xiong) were carried out, namely by reflux extraction, ultrasonic extraction, percolation extraction, cold-soaked extraction, microwave extraction and Soxhlet extraction, adopting flavonoids content as index. The results showed that the flavonoids yields in extracts are in the sequence of: ultrasonic extraction>microwave extraction>reflux extraction>percolation extraction>Soxhlet extraction>cold-soaked extraction. The ultrasonic extraction method was superior to other methods. This method had the advantages of fast extraction speed,no heating, be economical of time, solvent and energy, and had higher yield of flavonoids.
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    Extraction of Juglone from Bark of Juglans mandshurica Maxim. by Vacuum Distillation
    SUN Mo-long;SONG Zhan-qian;FANG Gui-zhen;LI Shu-jun;YUAN Hai-jian
    2007, 27 (6):  113-115. 
    Abstract ( 648 )   PDF (661KB) ( 704 )   Save
    Juglone(5-hydroxy-1,4-naphthaoquinone) is one of the active substances that was extracted from Juglans mandshurica Maxim. Juglone product was obtained from bark of J. mandshurica by ultrasonic extraction and vacuum distillation, and the yield of product was 0.09%. The product was characterized by FT-IR, GC-MS and 1H NMR. The result showed all the characteristic absorption peaks of hydroxyl-naphthaoquinone in the FT-IR spectrum of the product. The constituents of the product were determined by GC-MS to be: 1,4-naphthaoquinone, 5-hydroxy-1,4-naphthaoquinone and 7-methoxy-1-tetralone, and the content of juglone in the product was 96.42%. The structure of juglone in the product was confirmed by 1H NMR. This study offered a simple and effective method to get high purity juglone from bark of J. mandshurica.
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    Redox Adsorption of Cr(Ⅵ) by in Situ Immobilized Larch Tannin
    HOU Xu;LIAO Xue-pin;SHI Bi
    2007, 27 (6):  1-7. 
    Abstract ( 601 )   PDF (1235KB) ( 635 )   Save
    The adsorption behaviors of Cr6+ by in situ immobilized larch tannin were investigated. It was found that the adsorption is characterized by redox adsorption, that is, Cr6+ is first reduced into Cr3+ and then adsorbed. The adsorption capacity of this adsorbent to Cr6+ was 183.6 mg/g at 303 K when initial concentration of Cr6+ was 297.3 mg/L and pH value was 2.0, and the adsorption capacity was increased with the increase of temperature. The optimal pH value for the adsorption of Cr6+ was 2.0 because the reduction of Cr6+ is accelerated under acidic condition. The adsorption isotherm of Cr6+ by in situ immobilized larch tannin can be described by the Freundlich equation. The data of adsorption rate can be well fitted by the pseudo-second-order rate model. The breakthrough point of Cr6+ in adsorption column was around 120 bed volumes when the inlet concentration of Cr6+was 232.4 mg/L.
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    Study on Comprehensive Extraction of Antioxidant and Essential Oil from Rosemary(Ⅲ)——Supercritical CO2 Extraction
    BI Liang-wu;ZHAO Zhen-dong;LI Dong-mei;GU Yan;WANG Jing;LIU Xian-zhang
    2007, 27 (6):  8-12. 
    Abstract ( 705 )   PDF (789KB) ( 665 )   Save
    Supercritical CO2 extraction(SCDE) is a kind of effective comprehensive extraction for antioxidant and essential oil of rosemary(Rosmarinus officinalis L.). In this study, the optimal conditions of comprehensive extraction for antioxidant and essential oil of rosemary were as follows: extraction time 4 h, 95%(volume fraction) ethanol as entrainer to rosemary leaves 2:5, temperature of extraction pot 50℃, temperature of separation pot I 70℃, temperature of separation pot Ⅱ 40℃, extraction pressure 20 MPa and separation pressure 4-5 MPa. Average yield of rosemary oil was 1.80%. Results of constituent analysis of rosemary oil showed that the essential oil mainly contains 1,8-cineole, camphor, α-terpineol, borneol, verbenone, terpinen-4-ol, bornyl acetate and linalol. Average yield of rosemary antioxidant was 11.93%. Main active components of rosemary antioxidant were carnosic acid, carnosol, and rosmarinic acid, whose contents were 23.61%, 7.33% and 5.13%, respectively.
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    Preparation and Application of Urushiol Resin Catalyst Doped Chemically with Molybdovanadophosphoric Acid
    SANG Qiu-zhang;YANG Chun-hai;SHI Bo-an;YU Ai-nong
    2007, 27 (6):  13-16. 
    Abstract ( 692 )   PDF (687KB) ( 477 )   Save
    Urushiol resin catalyst doped chemically with molybdovanadophosphoric acid(UR-HPA) was prepared by polymerization method. The prepared resin was characterized by FT-IR and thermogravimetry(TG-D-TG). The results showed that chemical bond was formed between molybdovanadophosphoric acid and urushiol resin. The catalytic activity of the resin was investigated by synthesis of ketals. In the system of cyclohexanone-ethlene glycol ketal(CHGK) catalyzed by UR-HPA, CHGK yield is 88.4%. The catalyst can be reused for fifteen times, keeping CHGK yield at 85.2%.
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