Table of Content

28 February 2015, Volume 35 Issue 1 Previous Issue    Next Issue

Select

Transesterification Performance of Acidic Group Modified Mesoporous MCM-41 Membrane CHEN Li-hua, LI Zun-shan, GAO Li-jing, XU Wei, XIAO Guo-min 2015, 35 (1):  1-8.  doi: 10.3969/j.issn.0253-2417.2015.01.001 Abstract ( 598 )   PDF (1583KB) ( 723 )   Save MCM-41 with long range ordered hexagonal mesostructures was loaded on the surface of ceramic membranes (CM) successfully by in situ synthetic method. Then, the MCM-41/CM was modified by loading SO42-/ZrO2 in order to prepare solid acid catalyst SO42-/ZrO2/MCM-41/CM. The catalytic performance of the synthesized catalyst was evaluated by transesterification using palm oil and methanolas reactants. The results showed that the SO42-/ZrO2/MCM-41/CM had good catalytic activity with Zr(NO3)4 solution concentration of 0.4 mol/L, H2SO4 solution concentration of 2 mol/L, and calcination temperature of 550 ℃. The optimal reaction conditions for transesterification were as follows: catalyst amount (active components loaded ratio) 5%, reaction time 60 min, reaction temperature 100 ℃, methanol/palm oil molar ratio 10:1. The yield of fatty acid methyl ester (FAME) is up to 92% under this condition. References | Related Articles | Metrics

Select

A Novel Method for Preparation of (3R,4R)-4,7,7-Trimethyl-6-oxabicyclo [3.2.1] octane-3,4-diol HUANG Dao-zhan, ZHU Shou-ji, LAN Hong-yun, LEI Fu-hou 2015, 35 (1):  9-15.  doi: 10.3969/j.issn.0253-2417.2015.01.002 Abstract ( 674 )   PDF (843KB) ( 649 )   Save (3R,4R)-4,7,7-trimethyl-6-oxabicyclo [3.2.1] octane-3,4-diol was prepared by reaction of α-pinene with 30 % H2O2 in presence of dodecyl pyridinium peroxyopolyphosphotungstate catalyst (Cat-PW4). The effects of different reaction factors on the conversion rate and selectivity were investigated. The optimal conditions are as follows: α-pinene, 12.8 mmol; chloroform as solvent, 5 mL; reaction temperature, 40 ℃; Cat-PW4 as catalyst, 0.2 g; 30 % H2O2, 3.3 mL; reaction time, 3 h. Under these conditions, the conversion rate of α-pinene reached 94.7 %, and the selectivity for the title compound reached 39.8 %. The product existed both in aqueous phase and organic phase and could be isolated from reaction mixtures by extraction and re-crystallization. It was structurally identified by means of IR, UV, 1H NMR, 13C NMR, GC/MS, and HR-ESI-MS. Its yield and purity were 11 % and 98 %, respectively. References | Related Articles | Metrics

Select

Preparation of Spherical Activated Carbon from Alkali Lignin LI Ke, LI Wei, LIU Shou-xin 2015, 35 (1):  16-22.  doi: 10.3969/j.issn.0253-2417.2015.01.003 Abstract ( 727 )   PDF (3931KB) ( 749 )   Save Spherical activated carbon was prepared from the industrial alkali lignin via three steps:preparation of spherical lignin precursor, carbonization, and activation. Effects of preparation and activitation conditions of spherical lignin precursor on its morphology and particle size of the spherical activated carbon were investigated. SEM, N2(77K) adsorption-desorption isotherm, and FT-IR were used for characterizing its morphology structure, adsorption property, and surface functional groups, respectively. The results showed that spherical lignin precursor with diameter of approximate 5 μm could be obtained under the reaction temperature 90 ℃, stirring rate 200 r/min, reaction time 10 h, and pH 3.0. After carbonization at 300 ℃ followed by activation at 850 ℃, spherical activated carbon with BET surface area of 776.96 m2/g, total pore volume of 0.487 1 cm3/g, and average pore diameter of 2.51 mm could be obtained. References | Related Articles | Metrics

Select

Synthesis of Cellulose-g-PMMA and Its Micelles Using as Drug Carriers ZHONG Li-li, GAO Yuan, ZHANG Li-ping 2015, 35 (1):  23-29.  doi: 10.3969/j.issn.0253-2417.2015.01.004 Abstract ( 690 )   PDF (1143KB) ( 743 )   Save Cellulose chloracetate, as a macromolecular initiator, was prepared by using cellulose as raw material, and ionic liquid as the reaction medium. Then, it was used for atom transfer radical polymerization to prepare cellulose-g-polymethyl methacrylate (cellulose-g-PMMA) using methyl methacrylate (MMA) as monomer and cellulose ester/CuBr/2,2-bipyridyl as the initiator system. The cellulose-g-PMMA was characterized by FT-IR, XRD, TGA and so on. The crystalline degree of cellulose is 57.9%, and fall to 38.39% by chemical modification. In the selective solvent acetone, the average particle diameter of the product was about 40-70 nm. TEM images showed that the copolymer micelles was spherical shape and the particle size was about 200 nm with core-shell structure. Aspirin was used as a model drug loading in the copolymer micelles to investigate the influence of the degree of cellulose modification on drug release efficiency. Drug release time of the cellulose-g-PMMA obtained by grafted polymerization for 3 h had 88.9% drug release rate after 72 h at 37℃. This cellulose-g-PMMA exhibited a good effect on drug release. References | Related Articles | Metrics

Select

Synthesis and Fungicidal Activity of Camphoric Acid-based Benzenesulfonamide Compounds MA Xian-li, MIN Fang-qian, DUAN Wen-gui, LI Fang-yao, LIU Lu-zhi, CEN Bo, LEI Fu-hou 2015, 35 (1):  30-38.  doi: 10.3969/j.issn.0253-2417.2015.01.005 Abstract ( 774 )   PDF (892KB) ( 605 )   Save Camphoric anhydride was prepared via dehydration reaction using camphoric acid as starting material. Then, N-aryl sulfonyl ethyenediamines were synthesized by the reaction of ethylenediamine with substituted benzenesulfonyl chlorides, followed by the reaction of camphoric anhydride with N-aryl sulfonyl ethyenediamines to obtain eleven novel camphoric acid-based benzenesulfonamide compounds:camphoric acid-based benzenesulfonamide(4a), camphoric acid-based p-methyl-benzenesulfonamide(4b), camphoric acid-based m-methyl-benzenesulfonamide(4c), camphoric acid-based p-methoxy-benzenesulfonamide(4d), camphoric acid-based m-methoxy-benzenesulfonamide(4e), camphoric acid-based p-fluoro-benzenesulfonamide(4f), camphoric acid-based o-fluoro-benzenesulfonamide(4g), camphoric acid-based p-chloro-benzenesulfonamide(4h), camphoric acid-based m-chloro-benzenesulfonamide(4i), camphoric acid-based p-bromo-benzenesulfonamide(4j), and camphoric acid-based m-bromo-benzenesulfonamide(4k). The synthetic conditions were investigated preliminarily. The suitable synthetic conditions for the target compounds were as follows:anhydrous ethanol as solvent, reaction temperature 80 ℃, n(camphoric anhydride):n(N-aryl sulfonyl ethyenediamine) 1:1.2. The target compounds were characterized by FT-IR, 1H NMR, 13C NMR and ESI-MS, respectively. The preliminary bioassay showed that most of the title compounds exhibited certain fungicidal activity at the concentration of 50 mg/L, in which compounds 4a and 4e had inhibition rate of 94.8 % against Physalospora piricola, and compound 4h had inhibition rate of 86.9 % against Alternaria solani. References | Related Articles | Metrics

Select

Hydrophobic and Rheological Properties of Acetylated Wood Flour Based Composites XIE Zhen-hua, ZHANG Ming-ming, JIN Li-wei 2015, 35 (1):  39-44.  doi: 10.3969/j.issn.0253-2417.2015.01.006 Abstract ( 742 )   PDF (1897KB) ( 848 )   Save Blends of wood fluor (WF), acetylation wood flour (AWF) with low density polyethylene (LDPE) and polylactic acid (PLA) were produced by twin-screw extruding and injection molding, respectively. Hydrophobicity, rheology, mechanical properties, and morphology of the composites were measured by moisture absorption, contact angle measurement, rotational rheometer, tensile tests and scanning electrical microscope (SEM), respectively. The results showed blending composites of AWF had better hydrophobic performance, and its moisture absorption reduced significantly compared with blending composites of WF. The moisture absorption decreased with the decrease of AWF content in composites, and the contact angle increased. Compared with WF/LDPE composites, AWF/LDPE composites had less viscosity and storage modulus. The viscosity and storage modulus of AWF/LDPE composites decreased with the decrease of AWF. The tensile strength of AWF blend composites was lower than that of WF blend composites, but the elongation at break showed a substantial increase. The results of SEM showed that the compatibility between AWF and plastic matrix was improved, and they adhered and blended more closely. References | Related Articles | Metrics

Select

Catalytic Synthesis of Terpene Alcohol Aromatic Ester with Carica papaya Lipase in Non-aqueous System SU Er-zheng, YOU Peng-yong, WEI Dong-zhi 2015, 35 (1):  45-50.  doi: 10.3969/j.issn.0253-2417.2015.01.007 Abstract ( 733 )   PDF (848KB) ( 660 )   Save In order to establish economic, green and efficient synthesis process of terpene alcohol aromatic ester, naturally immobilized Carica papaya lipase (CPL) was prepared from the crude papain, and was used to catalyze the synthesis of terpene alcohol aromatic ester in non-aqueous system. The effects of terpene alcohol type, organic solvent type, and initial water activity on the CPL catalyzed reaction were investigated. The results showed that the primary terpene alcohols (geraniol and citronellol) were more suitable substrates, solvents with moderate polarity such as n-hexane were suitable reaction medium, and initial water activity of 0.328 benefitted the catalytic activity of CPL in organic solvents. Under these conditions, the substrate conversion rate was 95.2%, which was similar to those of commercial lipases. The reusability of CPL in organic solvent was poor. Three treatment methods by introduction of the ionic liquid were investigated on their effects on CPL catalyzed performance. It was found that wrapping the CPL with trace amount of ionic liquid before use could significantly enhance the CPL stability. The catalytic activity of CPL still remained more than 90% after being used in the organic solvent for 15 batches. References | Related Articles | Metrics

Select

Reduction of Monobasic Alcohol Abietate in Supercritical Hexane YIN Bin, ZENG Tao, WANG Xue-yuan 2015, 35 (1):  51-56.  doi: 10.3969/j.issn.0253-2417.2015.01.008 Abstract ( 786 )   PDF (938KB) ( 670 )   Save Reduction of a series of monobasic alcohol abietates over Cu-Zn catalysts was studied in supercritical hexane phase. The effects of the amount of Cu-Zn catalyst, and hexane, reaction temperature, reaction pressure, and reaction time on the conversion rate and selectives of abietate were investigated. Methyl abietate, butyl abietate, and octyl abietate were used as materials. The conversion rates reached 87.9%, 75.0% and 69.9%, the selectivities reached 93.4%, 92.4% and 92.8%, and the yields of abietinol reached 82.1%, 69.3% and 64.9%, respectively, when the reaction was conducted under the conditions of abietate 15 g, the amount of Cu-Zn catalyst 10%, the ratio of m(abietate) to m(hexane) 1:3, temperature 270 ℃, pressure 10 MPa, and reaction time 11 h. The analysis results of FT-IR and GC-MS showed that the ester group of abietate was reduced to hydroxyl group and the main components of the reduction products were dihydropimaric alcohol, dihydroabietic alcohol, tetrahydroabietic alcohol, and dehydropimaric alcohol. References | Related Articles | Metrics

Select

Modification of Acrylate Emulsion Adhesive with Aluminum Hydroxide and Its Flame Retardancy YU Xiang-dong, LIU Juan, CHEN Ri-qing, WANG Chun-peng, BU Hong-zhong 2015, 35 (1):  57-62.  doi: 10.3969/j.issn.0253-2417.2015.01.009 Abstract ( 684 )   PDF (938KB) ( 716 )   Save The acrylate emulsion adhesive (EL) modified with Al(OH)3 was prepared by mechanical mixing method. The effects of the types of polyacrylic acid sodium salt (DP) and sodium hexametaphosphate (SHMP), amounts of the dispersing agents, the amounts of the thickening agent and Al(OH)3 on the basic functions of the acrylate emulsion adhesive and its fluid mechanics performances was studied. The results showed that the acrylate emulsion adhesive had relatively good properties with viscosity of 1 360 mPa·s, pH value of 5.45, and better storage stability in 30 days. The oxygen index reached 32 under 0.35% of the dispersing agent SHMP, 0.20 % of the thickening agent hydroxyethyl cellulose(HEC), and 30% of the flame retardant Al(OH)3. The mechanical properties of fluids showed that the acrylate emulsion system was the elastic system of non-Newtonian pseudoplastic fluid. Compared with the acrylate emulsion adhesive, the flame retardant properties showed that the acrylate emulsion adhesive modified with Al(OH)3 had better flame retardant since the smoke and heat release decreased greatly. The reduction of CO generation was more than 50%, and the ignition time reduced. References | Related Articles | Metrics

Select

Variation of Chemi-mechanical Pulping Properties from Several Eucalyptus spp.Woodchips DENG Yong-jun, FANG Gui-gan, HAN Shan-ming, JIAO Jian, LI Hong-bin, LIANG Fang-min, LIN Yan, LIANG Long 2015, 35 (1):  63-69.  doi: 10.3969/j.issn.0253-2417.2015.01.010 Abstract ( 737 )   PDF (1254KB) ( 682 )   Save The fiber morphology and chemical composition of five kinds of eucalyptus(Eucalyptus urophylla×E.grandis,E.grandis×E.urophylla,E.urophylla,E.globules,E.tereticonis) wood chips were analyzed. Their properties of chemi-mechanical (P-RC APMP) pulping by preconditioning refiner and chemical alkaline peroxide were studied. The results showed that the holocellulose contents of the five different eucalyptus woods were between 77.96 %-81.36 %, in which E.tereticonis had the highest and E.grandis×E.urophylla the lowest. The lignin contents of these woods ranged from 23.18 %-26.62 %, in which E.urophylla had the highest and E.globules the lowest. Besides, there was very small difference in the fiber average length of the woods and it was between 755 and 785μm. Then five different eucalyptus wood chips were processed by P-RC APMP under the condition of impregnating with H2O2 5.0 % and NaOH 4.5%. As a result, E.tereticonis showed the highest pulp yield up to 86.7 %, while the pulp yield of E.grandis×E.urophylla was the lowest, 84.2 %. In addition, with the same Canadian Freeness Standard, E.globules pulp exhibited the best strength and optical properties and the lowest pulping power consumption. On the contrast, E.grandis×E.urophylla pulp showed the worst strength and optical properties, and the highest pulping power consumption. References | Related Articles | Metrics

Select

Comparison of the Products in Vacuum Pyrolysis Vapors Derived from Non-catalytic and Catalytic Upgrading of Camphorwood Sawdust FAN Yong-sheng, CAI Yi-xi, LI Xiao-hua, YU Ning, CHEN Lei 2015, 35 (1):  70-76.  doi: 10.3969/j.issn.0253-2417.2015.01.011 Abstract ( 697 )   PDF (420KB) ( 649 )   Save Direct catalysis of the vapors from biomass(camphorwood sawdust) vacuum pyrolysis was investigated over HZSM-5 zeolite in a two-stage fixed-bed reactor. Comparative analysis of the yield changes of each phase and the composition of the gas phase, as well as the physicochemical properties and chemical composition of bio-oil before and after catalysis was conducted. The results showed that the presence of catalyst decreased the bio-oil yield while bio-oil consisted of separable oil and aqueous phases. The H/C molar ratio, pH value and high heat value(HHV) of oil phase were 1.712, 4.93 and 37.15 MJ/kg, respectively. The use of HZSM-5 zeolite caused a remarkable increase of the target products including aromatic hydrocarbons, light phenols and alcohols, and a significant decrease of the unstable and corrosive compounds, such as carboxylic acids, aldehydes and ketones. The oil phase had higher qualities compared with raw bio-oil and could be used as an alternative fuel. The fuel added value of aqueous phase(dry basis) was also higher with HHV of 32.98 MJ/kg than that of raw bio-oil though it still contained a small amount of unstable and corrosive compounds. Transformation reactions of the non-target compounds on the HZSM-5 zeolite followed carbonium ions reaction mechanism. References | Related Articles | Metrics

Select

Synthesis and Slow-release Performance of Lignin Quaternary Ammonium Salt-urea Crosslinked by Glutaraldehyde TIAN Jin-ling, LUO Hua-chao, FANG Gui-zhen, REN Shi-xue 2015, 35 (1):  77-82.  doi: 10.3969/j.issn.0253-2417.2015.01.012 Abstract ( 925 )   PDF (890KB) ( 1162 )   Save In order to optimize the preparation conditions of lignin quaternary ammonium salt embedding urea and explore its application in the slow-release fertilizer production, lignin quaternary ammonium salt-urea (GCL-QA-U) crosslinked by glutaraldehyde was synthesized through inverse suspension method using trimethyl lignin quaternary ammonium salt (L-QA) as raw material, the Span 80 as dispersing agent, and glutaraldehyde as the crosslink agent. Its structure was characterized by FT-IR. The effects of the conditions, i.e., the dosage of crosslink agent, rotate speed, reaction time,and the dosage of dispersing agent, on the embedding of urea were discussed so as to obtain the best process conditions and product. Slow-release performance was then measured by water soluble and soil column leaching method. The results showed that quaternary amine group were successfully grafted. Urea was embedded in the L-QA, in which nitrogen content was 1.98 % and nitrogen content of GCL-QA-U was 2.88 %. The best process conditions of GCL-QA-U was the dosage of glutaraldehyde 4 mL, reaction time 2 h, rotate speed 200 r/min, and the dosage of dispersing agent 1.0 mL. And the maximal embedding rate of urea in GCL-QA-U was 41.61 %. The water soluble and soil column leaching method concluded that the urea accumulatived release amount were 5 % and 3.86 % during 24 h, respectively. The urea accumulatived release amount were 79.47 % and 74.80 % during 28 day, respectively. The slow-release effect of GCL-QA-U met the standard of slow-release fertilizer (GB-T23348—2009). References | Related Articles | Metrics

Select

Effect of Ball Milling on Accessibility of Morus alba Wood Flour YANG Rui, CHEN Xiao, YU Ji, HONG Jian-guo 2015, 35 (1):  83-88.  doi: 10.3969/j.issn.0253-2417.2015.01.013 Abstract ( 751 )   PDF (2545KB) ( 546 )   Save In order to increase the accessibility of reagent's acting on wood powder in the modifying procedure,Morus alba wood flour was pretreated by planetary ball milling. The effects of dry and wet grinding methods as well as milling time on the particle size,crystallinity,and iodine adsorbance were investigated. The results showed that wood flour reached its minimum size after dry milling for 4 h,and the median diameter (D50) was 8.982 μm. Moreover,the crystallinity of cellulose decreased obviously. Reunion phenomenon occurred when dry milling time was more than 4 h, so the particle size increased gradually. And the degree of crystallinity stayed unchanging with the increase of the milling time. The smaller the particle size of wood powder was,the higher the accessibility would be. Under the effects of the dispersion and inhibited reunion of water,the particle size gradually decreased with the increase of wet milling time. D50 reached 4.357 μm when milling time was 12 h. In addition,the method of desiccation exerted tremendous influence on the accessibility of wet milling wood powder. The accessibility of sample by oven-drying was lower than that of the un-milling wood powder and reduced with the decrease of particle size. However,the accessibility of sample by freeze-drying increased significantly compared with un-milling wood powder and was higher than that of wood powder which was drying milling for the same time. References | Related Articles | Metrics

Select

Pretreatment of Cassava Starch and Its Effect on Enzymatic Synthesis of Rosin Starch Ester LI He, LIN Ri-hui, LONG Han, WANG Sheng, CHEN Ran-qiong, WEI Cheng-yu 2015, 35 (1):  89-93.  doi: 10.3969/j.issn.0253-2417.2015.01.014 Abstract ( 895 )   PDF (1032KB) ( 556 )   Save Pretreatment of cassava starch with NaOH/Urea and its effect on enzymatic synthesis of rosin starch ester were studied in this paper. The granule morphology and crystal structure of pretreated cassava starch were characterized by SEM, FT-IR, and XRD methods. The results showed that the granule of starch still maintained a certain round or oval morphological structure after pretreatment, but its surface was broken and exhibited some kinds of crack. The crystallinity of pretreated cassava starch was reduced. Based on the comparison of physicochemical properties between cassava starch and pretreated cassava starch, it was showed that the dissolution rate and transparency of pretreated cassava starch increased 38.2 percent and 9.1 percent, and the relative viscosity went down. Enzymatic esterifications of cassava starch and pretreated cassava starch with rosin were carried out. The degree of substitutions(DS) of the esterifications were determined in order to investigate the effect of pretreatment on the reaction. The results indicated that pretreatment increased the degree of substitution of esterified products remarkably, and the DS value of 0.102 was achieved. FT-IR analysis showed that a new peak at 1720 cm-1 was observed in the spectra of esterified products produced from pretreated cassava starch, which corresponded to CO stretching in the ester group. The results indicated that the chemical reactivity of pretreated cassava starch increased significantly. References | Related Articles | Metrics

Select

Vacuum Pyrolysis Behavior of Cellulose, Xylan and Lignin and the Analysis of Liquefied Compositions YIN Hai-yun, LI Xiao-hua, FAN Yong-sheng, YU Ning, CAI Yi-xi 2015, 35 (1):  94-100.  doi: 10.3969/j.issn.0253-2417.2015.01.015 Abstract ( 784 )   PDF (1094KB) ( 867 )   Save The molecular structure of three components (cellulose, xylan, and lignin) in biomass was detected by Fourier transform infrared spectroscopy (FT-IR). The vacuum pyrolysis behavior and kinetics of the three components were investigated.The vacuum pyrolysis mechanism was studied on the basis of gas chromatography-mass spectrometer (GC-MS) analysis for bio-oils obtained from the vacuum pyrolysis. It was found that the cellulose contained molecular structures such as pyran ring and β-glucosidic bond. During the pyrolysis process temperature from 250 ℃ to 400 ℃, the yield was 73.79% and main products generated from pyrolysis were 2,5-dimethyl-furan (9.32%), hydroxyacetone (5.13%) 2,6-dimethoxy-phenol (5.72%) and levoglucosan (17.04%). Due to high content of side-chain groups, the xylan performed thermal unstability under high temperature. The main pyrolysis products were hydroxyacetone (18.42%), acetic acid (10.11%) and furfural (13.15%). Lignin contained amounts of aromatic substances, which trends to represent slow pyrolysis process and a wider range of pyrolysis temperature from 185 ℃ to 550 ℃. The solid residue from pyrolysis of lignin was up to 29.67% with the main pyrolytic products such as phenols (16.24%) and guaiacol (20.37%). References | Related Articles | Metrics

Select

Neutral TEMPO Oxidation of Bamboo Cellulose Fiber under Microwave Radiation and Its Characterization XIANG Xiu-dong, WAN Xiao-fang, LI You-ming, WU Shu-bin 2015, 35 (1):  101-106.  doi: 10.3969/j.issn.0253-2417.2015.01.016 Abstract ( 986 )   PDF (874KB) ( 650 )   Save The bamboo fibers were pretreated by microwave radiation and neutral 2,2,6,6-tetramethylpiperidinooxy(TEMPO) oxidation, and then the microfibrillated cellulose was prepared by ultrasonic mechanical treatment. Experimental results showed that the maximal carboxyl content was 0.729 mmol/g pulp after bamboo fibers were pretreated by 0.15 mmol/g TEMPO, 10 mmol/g NaClO2 and 1 mmol/g NaClO at 60 ℃ for 2 h. And the yield of microfibrillated cellulose was 85.7% after the ultrasonic mechanical treatment. The FT-IR spectra indicated that carboxyl groups were introduced onto cellulose. The XRD analysis indicated that the oxidation reaction was conducted only in the amorphous region or on the crystalline surface area of the cellulose. Meanwhile, the polymerization degree results of the cellulose showed that only minor cellulose fibers were degraded when they were pretreated by microwave radiation and neutral TEMPO oxidation. Therefore, the origin length of fiber was constant through this whole pretreatment process. References | Related Articles | Metrics

Select

Microwave-assisted Liquefaction of Five Types of Biomass in Polyhydric Alcohols LI Gai-yun, ZHU Xian-chao, ZOU Xian-wu, QIN Te-fu 2015, 35 (1):  107-112.  doi: 10.3969/j.issn.0253-2417.2015.01.017 Abstract ( 766 )   PDF (748KB) ( 640 )   Save Poplar, Chinese fir, bamboo, rice straw, and hemp xyloid stem were selected to investigate the effects of species on microwave-assisted liquefaction behaviors in polyhydric alcohols. Among the five types of biomass feedstocks, poplar and Chinese fir were easily liquefied, and bamboo and hemp xyloid stem were more difficult to be liquefied than poplar and Chinese fir. But rice straw was the most difficult to be liquefied. While the hydroxyl value of liquefied products(LP) of rice straw was the highest and that of Chinese fir was the lowest. It was found that both extract benzene-alcohol content and ash content had strong side effects on microwave-assisted biomass liquefaction. When the ratio of polyhydric alcohol to biomass was 2.5 and 3, co-liquefied fraction of mixed biomass of poplar, Chinese fir, bamboo, and hemp xyloid stem were 91% and 95%, respectively. This was notably higher than the yield of single bamboo and hemp xyloid stem. The hydroxyl value of LP of mixed biomass was close to that of bamboo. And its chemical components differed significantly from hemp xyloid stem. It would conclude that the synergistic effect exited in the co-liquefaction of mixed biomass feedstock. References | Related Articles | Metrics

Select

Catalytic Gasification of Wheat Straw Char at Low Temperature YU Yuan-yuan, XIAO Jun, SHEN Lai-hong, DU Yu-zhao 2015, 35 (1):  113-120.  doi: 10.3969/j.issn.0253-2417.2015.01.018 Abstract ( 791 )   PDF (1051KB) ( 791 )   Save The steam gasification of wheat straw char (WSC) and pickling wheat straw char (PWSC) at 700 ℃ were carried out. The effects of alkali metal content in wheat straw (WS) ash and catalyst species (K-based, Ca-based and Fe-based) on the gasification process were investigated. The results show that high content of alkali metal potassium in wheat straw ash can effectively promote the gasification of char. This results in a carbon conversion efficiency of 63.4 % without catalyst. This conversion rate is 2.6 times higher than that of the pickling wheat straw char (PWSC). At low temperature, the K-based catalyst exhibits a positive effect on the gasification of char. The H2 yield is 118.60 mol/kg with carbon conversion efficiency 98.5 % under the condition of K/Al catalyst at 700 ℃. The H2 yield and carbon conversion efficiency increased by 10.7 % and 12.4 % comparaed with that with Ca/Al catalyst, respectively. The H2 yield and carbon conversion efficiency increased by 20.5 % and 31.0 % compared with Fe/Al catalyst. Ca/Al and Fe/Al catalysts can promote the water gas shift reaction, which trends to elevate the H2 volume fraction, and reduce the CO volume fraction in the gasification products. By considering the carbon conversion, gas yield and gas composition volume fraction, the combination of certain Ca-based catalyst and K-based catalyst can regulate the gas composition. This generates a hydrogen rich gas with further purification. References | Related Articles | Metrics

Select

Extraction, Separation, and Immunoregulatory Activity of Saponins from Ophiopogon japonicus (L.f.) Ker-Gawl XIONG Shuang-li, LI An-lin, HUANG Ni 2015, 35 (1):  121-125.  doi: 10.3969/j.issn.0253-2417.2015.01.019 Abstract ( 646 )   PDF (753KB) ( 677 )   Save The extraction process of the total saponins in the root of Ophiopogon japonicus by ultrasonic wave was optimized through orthogonal test. Then the saponins were separated by the HZ-801 absorbent resin and the purified samples were identified with chemical and chromatographic method. At last, the immunoregulatory activities of total saponins were studied in vitro. The optimal combination parameters of the extracting technology for 100 g tuber of Ophiopogon japonicus were extracting temperature 60 ℃, ethanol volume fraction 70%, the ratio of ethanol to material 15:1, extracting time 2 h, and extracting twice. The yield of total saponins was (0.508±0.23)%. It was found that three different fractions, named ophiopogonin B(15.4%), A(40.6%), and C(12.6%), were proved to be steroidal saponins by chemical test. Saponin, which was purified preliminarily by ether and n-butyl alcohol and sodium hydroxide, had prominent immunoregulatory activities, i.e., remarkable macrophage-activating capability and nitric oxide and interleukin-1 producing ability. References | Related Articles | Metrics

Select

Solvent-thermal Degradation of Waste Lignin over Ni-Based Catalysts in the Presence of Homogeneous Acids HUANG Mei, LUO Jia, FANG Zhen 2015, 35 (1):  126-132.  doi: 10.3969/j.issn.0253-2417.2015.01.020 Abstract ( 620 )   PDF (1675KB) ( 739 )   Save Lignin was degraded to monomers and oligomers by thermochemical method. The yield and quality of degraded oil were different under different amount of solvents, homogeneous acids, and Ni-based catalysts. The results showed that the co-solvent of methanol and water promote the degradation of lignin. The residue yield decreased to 14.9% with the oil product yield increased to 44.1% in water/methanol/formic acid solvent. The addition of homogeneous acids (HCl and H3PO4) and heterogeneous catalysts (Ni and Ni/SiAl) not only improves the degradation of raw material, but also inhibits the condensation of degraded products. The obtained oils mainly contain monomers and oligomers. Ni/SiAl catalyzes the reforming of unsaturated aliphatic hydrocarbons and reduces oxygenic functional groups at the same time. This significantly decreases the yield of oil. Good oil quality with considerable oil yield (41.7%) was obtained under Ni catalyst. References | Related Articles | Metrics

Select

Optimized Preparation of Pomegranate Peel Extracts Microspheres Using Central Composite Design and Response Surface Method CHI Xue, ZHANG Dan-dan 2015, 35 (1):  133-137.  doi: 10.3969/j.issn.0253-2417.2015.01.021 Abstract ( 771 )   PDF (825KB) ( 617 )   Save The pomegranate polyphenol was extracted by the ultrasonic method, and the emulsification-crosslinking technique was used to prepare microspheres of pomegranate peel extracts. The effects of reaction conditions, i.e., chitosan deposit time, amount of sodium alginate, and emulsifier dosage on loading efficiency, were optimized by using response surface method. The results showed that under the optimal conditons, the yield of dry extract of pomegranate peel was 50.5% and the polyphenol content of the extract was 47.8%. The data of microspheres were fitted using binomial equation (r=0.994). The optimum preparation conditions were follows: sodium alginate concentration 0.98%, chitosan deposit time 2.56 h, emulsifier concentration 17.83%, curing time 5 h, amount of glutaraldehyde 1 mL. Under above conditions, the loading efficiency of microspheres was 12.19%. There was slight difference between the actual value and predicted value. Under optimal conditions, DPPH radical scavenging rate was 96.92%, and the bacterial inhibition diameters of Micrococcus tetragenus, Bacillus subtilis, Staphylococcus aureus were 2.70, 2.78 and 2.72 cm, respectively. Pomegranate peel extract and its microspheres, which were treated under 37 ℃ and relative humidity 75%, had the DPPH radical scavenging rates of 78.53% and 91.26%, respectively. References | Related Articles | Metrics

Select

Research Progress in Cellulose Hydrolysis by Carbonaceous Solid Acid LIU Wan-yu, QI Wei, ZHOU Jin-song, YUAN Zhen-hong, ZHUANG Xin-shu 2015, 35 (1):  138-144.  doi: 10.3969/j.issn.0253-2417.2015.01.022 Abstract ( 944 )   PDF (816KB) ( 814 )   Save In this paper,the latest research progress in cellulose hydrolysis by biomass carbon-based solid acid catalysts was reviewed. First raw materials and methods of catalyst preparation, including pyrolysis carbonization-sulfonated method, sulfuric acid charring-sulfonated, hydrothermal carbonization-sulfonated method and pyrolysis carbonization-oxidation-sulfonation method, were introduced. The mechanism of catalytic cellulose hydrolysis was analyzed, too. The factors and conditions affecting the catalytic hydrolysis reaction were discussed, and the applications and development direction of the carbonaceous solid catalysts in cellulose hydrolysis were prospected as well. References | Related Articles | Metrics

Select

Progress in Reforming Purification Technology of Biomass Fuel Gas DING Ming-yue, XIONG Wei, TU Jun-ling, ZHANG Qi, WANG Tie-jun, MA Long-long, LI Yu-ping 2015, 35 (1):  145-150.  doi: 10.3969/j.issn.0253-2417.2015.01.023 Abstract ( 658 )   PDF (675KB) ( 645 )   Save The technologies on tar purification and component adjustment of biomass raw gases were reviewed. The influence factors such as gasification conditions and added materials of gasifier purification technology were analyzed. Some widely used gasifier downstream purification reforming catalysts such as natural mineral catalyst, carbonate catalyst and nickel-based catalyst were introduced. Component adjustment of biomass raw gases was presented briefly. The problems and development direction in this field were discussed,too. References | Related Articles | Metrics