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Remarkably reducing carbon loss and H2 consumption on Ni–Ga intermetallic compounds in deoxygenation of methyl esters to hydrocarbons

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Journal of Energy Chemistry 2020年第2期29卷 194-208页

作者： Ning Zhao Ying Zheng Jixiang Chen Tianjin Key Laboratory of Applied Catalysis Science and Technology Department of Catalysis Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

Ni–Ga alloy(Ni/Ga atomic ratio of 8),Ni3Ga and Ni5Ga3 intermetallic compounds(IMCs)catalysts were prepared from Ni–Mg-Al-Ga layered double hydroxides(LDHs)for the deoxygenation of methyl esters to hydrocarbons.In the alloy and IMCs,the presence of Ga reduced the surface Ni atom density,and the charge transfer from Ga to Ni increased the electron density of Ni.In the deoxygenation of methyl laurate,the Ni catalyst gave a complete hydrogenolysis of methyl laurate to CH4at 330°C and 3.0 MPa,while the presence of Ga promoted the HDO pathway and suppressed C–C bond hydrogenolysis and methanation.The Ni5Ga3 catalyst exhibited the best desired performance.Even at 400°C,it gave the yield of C11 and C12 hydrocarbons of ~99%,and the selectivity to CH4(SCH4) was only 2.4%.In the deoxygenation of methyl octanoate and methyl palmitate,the Ni5Ga3 catalyst also gave the yield of hydrocarbons above95%.Reactivity evaluation and methyl propionate-TPD and TPSR results indicate that the C–OCH3 bond instead of the O–CH3 one was cleaved on both Ni and bimetallic Ni–Ga catalysts.It is highlighted that methanol,derived from the C–OCH3 bond hydrogenolysis,mainly decomposed to CO and H2 on IMCs,while it was converted to methane on metallic Ni and alloy.It is of great significance that H2 could be yielded from the methyl ester itself.In short,the utilization of Ni–Ga IMCs can effectively reduce carbon loss and H2 consumption,all of which are ascribed to the geometric and electronic effects of Ga.

关键词： Ni–Ga intermetallic compounds Methyl ester Decarbonylation/decarboxylation Hydrodeoxygenation C–C bond hydrogenolysis Methanation

Heterocyclic Carbene-Catalyzed Hydride Transfer in the Hydroboration of Carbonyl compounds

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Chinese Journal of Chemistry 2019年第7期37卷 679-683页

作者： Tianhao Li Jianying Zhang Chunming Cui State Key Laboratory of Elemento-Organic Chemistry Nankai University 94 Weijin Road Tianjin 300071 China

N-Heterocyclic carbene (NHC) enabled the highly efficient catalytic hydroboration of a wide range of ketones and aldehydes under mild conditions,and a new mechanism of catalytic hydroboration reaction which involves d... 详细信息

关键词： Hydride Transfer Carbonyl compounds

Production of aryl oxygen-containing compounds from catalytic pyrolysis of bagasse lignin over LaTixFe1xO3

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1939-1944页

作者： Haiying Wang Hongjing Han Enhao Sun Yanan Zhang Jinxin Li Yanguang Chen Hua Song Hongzhi Zhao College of Chemistry&Chemical Engineering Northeast Petroleum UniversityDaqing 163318China Provincial Key Laboratory of Oil&Gas Chemical Technology Daqing 163318China Daqing Petrochemical Research Center PetroChinaDaqing 163000China

A new approach,named production of aryl oxygen-containing compounds from the catalytic pyrolysis of bagasse lignin(BL) over perovskite oxide,was proposed,A series of LaTixFe1-xO3(LTF-x) samples were prepared by the solid state reaction method.The crystal phase and morphology of LTF-x were characterized by XRD and SEM respectively.Catalytic pyrolysis performance of LTF-x was performed by TG-DTG and the distribution patterns of gaseous,liquid and solid products from BL was investigated using a fixed-bed micro-reactor.The optimal reaction conditions were determined:the pyrolysis temperature was 600℃,the mass ratio of mBL:mLTF-0.2 was 3:1,the veloeity of earrier gas was 100 ml·min-1.The gaseous produets were mainly eomposed of CO2,CO,CH4 and CnHm(n=2-4,m=2 n+2 or m=2 n),The main aryl oxygen-containing compounds in liquid products were phenolics,guaiacols,syringols and phenylates,the rest were benzenes,furans,esters and carboxylic acid.The total contents of aryl oxygencontaining compounds were from 62% up to more than 72% under the action of the perovskite.Moreover,the LTF-0.2 sample had nice regenerability.

关键词： Bagasse lignin Perovskite Catalytic pyrolysis Aryl oxygen-containing compounds

Concentration control of volatile organic compounds by ionic liquid absorption and desorption

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2383-2389页

作者： Xiaobin Ma MinyanWu Shuo Liu Jinxing Huang Bin Sun Ying Zhou Qiulian Zhu Hanfeng Lu Institute of Catalytic Reaction Engineering College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China Hangzhou Runxin Technology Co.Ltd. Hangzhou 310014China

Volatile organic compounds(VOCs)are difficult to be eliminated safely and effectively because of their large concentration fluctuations.Thus,maintaining a stable concentration of VOCs is a significant study.In this research,H2O,Tween-80,[Emim]BF4,[Emim]PF6,and[Hnmp]HSO4 were applied to absorb and desorb simulated VOCs.The ionic liquid[Emim]BF4 demonstrated the best performance and was thus selected for further experiments.As the ionic liquid acted as a buffer,the toluene concentration with a fluctuation of 2000–20000 mg·m-3 was stabilized at 6000–12000 mg·m-3.Heating distillation(90°C)was highly efficient to recover[Emim]BF4 from toluene.The regenerated[Emim]BF4 could retain its initial absorption capacity even after multiple cycles.Moreover,[Emim]BF4 had the same buffer function on various aromatic hydrocarbons.

关键词： Volatile organic compounds Concentration fluctuation Absorb and desorb Ionic liquid Buffer

Advances in extraction and analysis of phenolic compounds from plant materials

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Chinese Journal of Natural Medicines 2017年第10期15卷 721-731页

作者： XU Cong-Cong WANG Bing PU Yi-Qiong TAO Jian-Sheng ZHANG Tong Experiment Ceiter of Teaching and Learning Shanghai University of Traditional Chinese Medicine Shanghai 201203 China School of Phar nacy Shanghai University of Traditional Chinese Medicine Shanghai 201203 China

Phenolic compounds,the most abundant secondary metabolites in plants,have received more and more attention in recent years because of their distinct bioactivities.This review summarizes different types of phenolic compounds and their extraction and analytical methods used in the recent reports,involving 59 phenolic compounds from 52 kinds of plants.The extraction methods include solid–liquid extraction,ultrasound-assisted extractions,microwave-assisted extractions,supercritical fluid extraction,and other methods.The analysis methods include spectrophotometry,gas chromatography,liquid chromatography,thin-layer chromatography,capillary electrophoresis,and near-infrared spectroscopy.After illustrating the specific conditions of the analytical methods,the advantages and disadvantages of each method are also summarized,pointing out their respective suitability.This review provides valuable reference for identification and/or quantification of phenolic compounds from natural products.

关键词： Phenolic compounds Flavonoid Extraction Quantification Liquid chromatography Gas chromatography

Identification of anti-cancer compounds from natural products

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Chinese Journal of Natural Medicines 2020年第7期18卷 481-482页

作者： LU Jin-Jian WANG Yi-Tao State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China

Natural products serve as abundant resources with diversity of chemical structures,which has been widely explored for the pharmacological researches and drug discovery[1,2].They are generally isolated from microorgani... 详细信息

关键词： cancer abundant compounds

High-throughput computational screening for twodimensional magnetic materials based on experimental databases of three-dimensional compounds

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npj Computational Materials 2020年第1期6卷 350-361页

作者： Daniele Torelli Hadeel Moustafa Karsten W.Jacobsen Thomas Olsen Computational Atomic-scale Materials Design(CAMD) Department of PhysicsTechnical University of DenmarkDK-2800 Kgs.LyngbyDenmark

We perform a computational screening for two-dimensional(2D)magnetic materials based on experimental bulk compounds present in the Inorganic Crystal Structure Database and Crystallography Open Database.A recently proposed geometric descriptor is used to extract materials that are exfoliable into 2D derivatives and we find 85 ferromagnetic and 61 antiferromagnetic materials for which we obtain magnetic exchange and anisotropy parameters using density functional theory.For the easy-axis ferromagnetic insulators we calculate the Curie temperature based on a fit to classical Monte Carlo simulations of anisotropic Heisenberg models.We find good agreement with the experimentally reported Curie temperatures of known 2D ferromagnets and identify 10 potentially exfoliable 2D ferromagnets that have not been reported previously.In addition,we find 18 easy-axis antiferromagnetic insulators with several compounds exhibiting very strong exchange coupling and magnetic anisotropy.

关键词： magnetic compounds ferromagnetic

Synthesis, Fluorescence and Dielectric Properties of Two Novel compounds Based on Triethylenediamine Derivatives

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Chinese Journal of Structural Chemistry 2019年第4期38卷 605-612页

作者：邓思雨钱秀李木陈立庄 School of Environmental and Chemical Engineering Jiangsu University of Science and Technology

Two compounds C_8H_(18)N_2Br_3Mn_(0.5)(1) and C_(12)H_(26)N_2Cl_4Mn(2) based on triethylenediamine derivatives were synthesized by solution method and were characterized by elemental analysis, infrared spectroscopy, single-crystal X-ray structure analysis, fluorescence test, circular dichroism(CD) analysis and dielectric measurement, respectively. According to single-crystal X-ray determination, compound 1 crystallizes in the cubic system, space group Pa3 with a = b = c = 13.7246(5) ?, Z = 24, V = 2585.2(3) ?~3; and compound 2 crystallizes in the orthorhombic system, space group P212121 with a = 7.9716(13), b = 15.309(3), c = 15.804(3) ?, Z = 4 and V = 1928.7(6) ?3. Fluorescent analysis of compound 1 showed an intense emission band at 670 nm when the exciting radiation was set at 378 nm and fluorescent analysis of compound 2 showed an intense emission band at 515 nm when the exciting radiation was set at 363 nm. Dielectric constants of compounds 1 and 2 were measured at different frequencies with temperature variation.

关键词： triethylenediamine derivatives fluorescent compounds crystal structure permittivity properties

Inhibitory effect of tartary buckwheat seedling extracts and associated flavonoid compounds on the polyphenol oxidase activity in potatoes(Solanum tuberosum L.)

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Journal of Integrative Agriculture 2019年第9期18卷 2173-2182页

作者： LI Jun WANG Hui LU Yang MAO Tang-fen XIONG Jiang HE Sheng-ling LIU Hui Guizhou Biotechnology Institute Guizhou Academy of Agricultural SciencesGuiyang 550006P.R.China Food Processing Institute Guizhou Academy of Agricultural Sciences/Potato Engineering Research Center of Guizhou ProvinceGuiyang 550006P.R.China

To improve the processing quality of potatoes,phosphate buffer extract(PBE),50%ethanol(E50),and aqueous extract(AE)of tartary buckwheat seedlings were evaluated for their ability to inhibit the enzymatic browning of potatoes.The results suggest that all extracts of tartary buckwheat seedlings exert significant inhibitory effects on the polyphenol oxidase(PPO)activity in potatoes.The relative concentrations required for a 50%reduction in the PPO activity(IC50)were 0.21,0.28 and 0.41 mg mL^-1,for PBE,E50 and AE,respectively.The strongest inhibitory activity was observed for PBE,followed by E50 and AE.Four flavone compounds in the PBE of tartary buckwheat seedlings(i.e.,rutin,kaempferol-3-O-rutinoside,quercetin,and kaempferol)were identified by high-performance liquid chromatography.These compounds were subsequently evaluated for their roles in the inhibition of PPO from potatoes using a model system.The results indicated that rutin exhibited the highest inhibition rate on the PPO of potato.A synergistic inhibitory effect was observed by mixing rutin,kaempferol-3-Orutinoside,quercetin,and proteins.The inhibitory patterns of rutin,kaempferol-3-O-rutinoside,and quercetin on the enzyme were noncompetitive and reversible,with inhibitory constants of 0.12,0.31,and 0.40 mg mL^-1,respectively.Flavonoids from tartary buckwheat seedlings may exhibit a common mechanism with phenolic compounds,involving the blockage of the reaction of oxygen with PPO leading to the inhibition of the enzymes involved in browning.Based on these results,extracts of tartary buckwheat seedlings can be used as potent natural inhibitors.

关键词： tartary buckwheat natural inhibitor flavonoid compounds polyphenol oxidase potato