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SYNTHESIS OF DBN AND ITS CATALYTIC PERFORMANCE FOR METHANOL CARBONYLATION TO methyl formate

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Journal of Energy Chemistry 1995年第1期 119-127页

作者： LIU Xing-Quan WU Yu-Tang JIA Zhao-XiaChengdu Institute uf Organic ChemistryAcademia SinicaChengdu, Sichuan 610015 To whom correspondence should be addressed.

1 , 5-diazabicyclo[’1, 3, 0]non-5-ene(DBN) has been synthesized in our laboratory, and its catalytic activity and selectivity for methanol carbonylation to methyl formate (MF) have been studied. The experimental results have demonstrated that the synthetic processes of DBN used for the present work are reasonable and feasible. The total yield of three steps of DBN synthsis is approximate to 80%. The activity evaluation has shown that DBN can effectively catalyze the carbonylation reaction of methanol in the presence of propylene oxide (PO) promoter. PO-promoted DBN is a novel catalytic system superior to sodium methoxide.

关键词： synthesis of DBN DBN catalyst methanol carbonylation methyl formate propylene oxide promoter

Preparation of MIL-88B(Fe_(x),Co_(1‒x))catalysts and their application in one-step liquid-phase methanol oxidation to methyl formate using H_(2)O_(2)

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Chinese Journal of Catalysis 2021年第12期42卷 2254-2264页

作者： Jianfang Liu Zhenzhen Ran Qiyan Cao Shengfu Ji State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

The selective oxidation of methanol to methyl formate is one of the most attractive processes to obtain value-added methanol-downstream *** development of highly efficient and stable catalysts is critical for this *** this study,a series of MIL-88B(Fe_(x),Co_(1‒x))bimetallic catalysts with different Fe/Co molar ratios were prepared through a one-pot hydrothermal method.X-ray diffraction,scanning electron microscopy,high-resolution transmission electron microscopy,energy dispersive spectroscopy,Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,N2 adsorption-desorption,and inductively coupled plasma-mass spectrometry characterization were performed to elucidate the structure of the *** activity of the catalysts were assessed in the one-step oxidation of methanol to methyl formate with H_(2)O_(2)in a liquid-phase batch *** results show that the MIL-88B(Fe_(x),Co_(1‒x))catalysts exhibit uniform needle-like morphologies with an average length and width of 400-600 nm and 100-150 nm,***^(2+)is incorporated into the framework by partially replacing Fe^(3+)in ***,the catalyst efficiently promoted the conversion of methanol to methyl *** MIL-88B(Fe_(0.7),Co_(0.3))catalyst was used with a molar ratio of H_(2)O_(2)to methanol of 0.5 at 80℃for 60 min,34.8%methanol conversion was achieved,and the selectivity toward methyl formate was 67.6%.The catalysts also showed great stability with a steady conversion and selectivity even after four *** preliminary oxidation mechanism was also *** was determined that H_(2)O_(2)is first adsorbed on the Fe^(3+)sites and subsequently activates these *** is adsorbed by the O atoms of the framework through hydrogen bonding and is gradually oxidized to formic ***,formic acid reacts with the residual methanol at the Fe^(3+)and Co^(2+)Lewis acid sites to form methyl formate.

关键词： Bimetal-organic frameworks Methanol oxidation Liquid phase One-step transformation methyl formate

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Promoting effect of chloride ions on selective oxidation of methanol to methyl formate over zirconia-supported ruthenium oxide catalysts

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Journal of Energy Chemistry 2013年第3期22卷 512-516页

作者： Weizhen Li Hongpeng Zhang Xiaohui He Haichao Liu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable SpeciesCollege of Chemistry and Molecular EngineeringPeking University

The effect of chloride ions on a monoclinic ZrO2-supported RuOx （RuOx/m-ZrO2） catalyst with a Ru surface density of 0.3 Ru/nm2 was studied in the selective oxidation of methanol to methyl formate （MF） at a low temperature of 373 K. The m-ZrO2 support was Cl-free, and Cl- ions were introduced into the RuOx/m-ZrO2 catalyst by impregnation with zirconium oxychloride or ammonium chloride and subsequent thermal treatment in air at 673 K. The structures of these catalysts were characterized by X-ray diffraction, Raman and X-ray photoelectron spectroscopies. Their reducibility was probed by temperature-programmed reduction in H2. The RuOx domains were present as highly dispersed Rut42- structure on m-ZrO2 with similar reducibility for the RuOx/m-ZrO2 samples irrespective of modification with or without Cl ions. Introduction of appropriate amounts of zirconium oxychloride into RuOx/m-ZrO2 led to a remarkable increase in the methanol oxidation rate and MF selectivity, whereas introduction of ammonium chloride or zirconyl nitrate significantly inhibited the catalytic performance of RuOx/m-ZrO2. The promoting effect of Cl- ions derived from zirconium oxychloride can be tentatively attributed to their roles in facilitating the adsorption of methanol and desorption of MF product or its intermediates. This finding provides novel insights into the promoting effect of Cl- ions on oxides-based catalysts for selective oxidation reactions.

关键词： methanol oxidation ruthenium oxide monoclinic zirconia chloride promoting effect methyl formate

Semi-continuous reactive batch distillation for production of methyl formate

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Semi-continuous reactive batch distillation for production o...

Syntheses and Evaluations of CdS with Various Morphologies for Photocatalytically Reducing CO_2

2011 2nd Asia-Pacific Conference on Wearable Computing Systems

作者： Li Ying Qu Hongmei Tian Ye Song Shuang Bai Peng School of Chemical Engineering and Technology Tianjin University

Reaction kinetics of the esterification of methyl formate（MF） is studied in a batch reactor at different temperatures and the reliability of the estimated parameters is analyzed with Matlab using a fourth order Runge-Kutta method in the paper. Kinetic constants were experimentally examined and used to calculate the optimal operation parameters of semi-continuous reactive distillation for production of MF in order to minimize the amount of unconverted Formic Acid（FA） remained in the bottom. The results show that the optimal condition is obtained at the formic acid/methanol mole ratio of 0.5:1 and the mass fraction of formic acid at the bottom is 2% which is very close to the calculated value. Simulation work was carried out with Matlab and the results showed good agreement with the experimental data.

关键词： methyl formate Kinetic constant Semi-continuous batch reaction

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 78-84页

作者：杨晓晓 XIN Weiyue 尹晓红 SHAO Xiao Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of Technology School of Chemical Engineering East China University of Science and Technology

A series of CdS with various shapes of microsphere, flower-like and leaf-like were templatefreely synthesized by a hydrothermal method. Powder X-ray diffraction（XRD）, Brunauer-Emmett-Teller（BET）, scanning electron microscopy（SEM） and UV-vis absorption spectroscopy（UV-vis） were applied to characterize the morphology, optical and other physical properties of the as-prepared CdS. An optical spectrum analyzer was used to measure the wavelength of the illuminant on the slurry in the activity evaluations of photocatalytic reduction of CO2 over CdS. Both sources of cadmium and sulfur had great impact on the CdS morphology as can be seen in the SEM images. By means of a series of activity evaluations, the microspheric CdS made from cadmium nitrate and thioacetamide showed better photocatalytic activity for the reduction of CO2 to methyl formate（MF） in methanol than the flower-like and leaf-like CdS catalysts.

关键词： CdS morphology photocatalytic reduction CO2 methyl formate

Experimental and mechanistic understanding of photo-oxidation of methanol catalyzed by CuO/TiO2-spindle nanocomposite:Oxygen vacancy engineering

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Nano Research 2020年第4期13卷 939-946页

作者： Quanquan Shi Zhaoxian Qin Changlin Yu Ammara Waheed Hui Xu Yong Gao Hadi Abroshan Gao Li College of Science Inner Mongolia Key Laboratory of Soil Quality and Nutrient ResourceInner Mongolia Agricultural UniversityHohhot 010018China School of Chemical Engineering Key Laboratory of Petrochemical Pollution Process and Control Guangdong ProvinceGuangdong University of Petrochemical TechnologyMaomirtg 525000China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China School of Chemistry and Biochemistry Georgia Institute of TechnologyAtlantaGeorgia 30332USA

We report experimental and mechanistic understanding of methanol oxidation to produce methyl formate using CuO/Ti02-spindle composite as a promising photocatalyst under mild conditions with over 97%conversion and 83%*** catalysts are obtained via precise depositing of CuO nanoclusters(size:~3.5 nm)at the{101}facet of the TiO2 to optimally tune exciton recombination through oxygen vacancies generation,evidenced by photoluminescence and Raman spectroscopy *** turnover frequency(TOF)and the apparent quantum efficiency(AQE)of the 7%CuO/TiO2-spindle composites reach up to 23.8 molmethanol·gcat^-1·h^-1 and 55.2%at 25℃,respectively,which are substantially higher than these previously reported ***,the in-situ attenuated total reflection infrared spectroscopy analysis reveals that the methanol oxidation most likely takes place through the conversion of adsorbed methoxy(CH30^*)to formaldehyde(CHO^*)intermediate,a subject of major debate for a long *** adsorbed formaldehyde(CHO^*)thus produced reacts with another CH30^*species in its close proximity to form the final product of methyl *** of this study provide insights into the reaction mechanism,and offer guidelines to systematically develop and apply photocatalysts for methanol conversion and related reactions via surface engineering.

关键词： CuO/Ti02 nanocomposite methyl formate in-situ attenuated total reflection infrared spectroscopy photocatalysis oxygen vacancy methanol

Catalytic Oxidation of Dimethyl Ether to Hydrocarbons over SnO_2/MgO and SnO_2/CaO Catalysts

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Journal of Natural Gas Chemistry 2007年第2期16卷 200-203页

作者： Lin Yu Jieyu Xu Ming Sun Xuetao Wang Faculty of Chemical Engineering and Light Industry Guangdong University of Technology Guangzhou 510006 Guangdong China

A novel reverse microemulsion method was used to prepare SnO2/MgO and SnO2/CaO catalysts. It was found that both the catalysts were active for the reaction of catalytic oxidation of dimethyl ether （DME） in the temperature range of 275 to 300 ℃. SnO2/CaO catalyst exhibits much higher activity than SnO2/MgO. On SnO2/CaO catalyst, DME conversion of 21.8% was obtained at 300℃, while selectivities to methyl formate （MF） and dimethoxyethane （DMET） of 19.1% and 59.0% respectively were obtained at 275 ℃.

关键词： dimethyl ether catalytic oxidation methyl formate dimethoxyethane

KINETICS OF THE CARBONYLATION OF METHANOL IN A MECHANICALLY AGITATED REACTOR

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Journal of Energy Chemistry 1996年第3期 229-236页

作者： BAI Liang ZHAO Yu-Long HU Yun-Qing ZHONG Bing PENG Shao-Yi (This work was supported by the National Matural Science Foundation of China) (Institute of Coal Chemistry, The Chinese Academy of SciencesTaiyuan, Shanxi 030001)

The carbonylation of methanol using a sodium methoxide catalystwas studied in the temperature range of 60-110℃ and pressure range of2.0-4.0Mpa in a mechanically agitated reactor. A Kinetic rate expression forthe reaction is presented. The apparent activation energies for thecarbonylation and decarbonylation reactions were found to be 70.7kJ/moland 92.1 kJ/mol respectively. The negative effects of CO2 and H2O on thecarbonylation reaction were studied. The impurities react with the sodiummethoxide catalyst and stop the reation.

关键词： sodium methoxide carbonylation methanol methyl formate kinetics

Tiny pollutant emissions of a dimethyl ether fuelled engine

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Journal of Chongqing University 2008年第4期7卷 284-290页

作者：郎静张煜盛 Faculty of Energy and Power Engineering Huazhong University of Science and Technology

Emissions of dimethyl ether(DME) fuelled engines were investigated by orthogonal experiments on a ZS195 diesel *** study mainly focused on the tiny pollutant emissions of formaldehyde(CH2O),methyl formate(CH3OCHO) and formic acid(HCOOH).The presence of CH2O,CH3OCHO and HCOOH are proved in the exhaust by gas chromatograph and Fourier transform infrared *** analysis of variance results indicate that the fuel delivery advance angle is the most important factor for CH2O *** fuel delivery advance angle and the interaction of injection pressure and nozzle diameter are considerable factors for unburned hydrocarbon(UHC) *** mechanism forming tiny pollutants,primarily through CH2O formation,is suggested to be similar to the mechanism forming UHC by DME partial oxidation existing in crevices and boundary zones,and is verified via DME combustion simulation of a multizone chemical kinetic model.

关键词： dimethyl ether emission formaldehyde methyl formate formic acid