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Effect of NH_4^+ exchange on CuY catalyst for oxidative carbonylation of methanol

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Chinese Journal of Catalysis 2016年第8期37卷 1403-1412页

作者：王玉春郑华艳李忠太原理工大学煤科学与技术教育部和山西省重点实验室山西太原030024 运城学院应用化学系山西运城044000

NaY and ion exchanged NaNH4Y zeolite with NH4NO3 were used as the support to prepare CuY cata‐lysts by a high temperature anhydrous interaction between the support and copper （II） acety‐lacetonate Cu（acac）2. The catalysts were used for the oxidative carbonylation of methanol to dime‐thyl carbonate （DMC） at atmospheric pressure. The textural and acidic properties of NaNH4Y zeolite and the CuY catalysts were investigated by X‐ray diffraction, scanning electron microscopy, N2 ad‐sorption‐desorption, temperature programmed reduction of H2, X‐ray photoelectron spectroscopy and temperature programmed desorption of NH3. With increasing NH4NO3 concentration, the NH4＋exchange degree increased while the crystallinity of the zeolite remained intact. Crystalline CuO was formed when the NH4＋exchange degree of NaNH4Y was low, and the corresponding CuY catalyst showed low catalytic activity. With increasing of the NH4＋exchange degree of NaNH4Y, the content of surface bound Cu＋active centers increased and the catalytic activity of the corresponding CuY catalyst also increased. The surface bound Cu＋content reached its maximum when the NH4＋ex‐change degree of NaNH4Y reached towards saturation. The CuY exhibited optimal catalytic activity with 267.3 mg/（g·h） space time yield of DMC, 6.9%conversion of methanol, 68.5%selectivity of DMC.

关键词： High temperature anhydrous interaction NH4+exchange degree CuY catalyst oxidative carbonylation Dimethyl carbonate

Synthesis of Pd（C4H2O4）（C4H8N2）0.5 Complex and the Catalytic Activity for oxidative carbonylation of Phenol

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Chinese Journal of Chemical Engineering 2008年第3期16卷 354-356页

作者：程庆彦梁亚男高玲王延吉 Key Laboratory of Green Chemical Technology ＆ High Efficient Energy Saving of Hebei Province Hebei University of Technology Tianjin 300130 China Tianjin Honest Industry Co. Ltd. Tianjin 300382 China

A novel complex Pd（C4H2O4）（C4H8N2）0.5 has been synthesized by solvent thermal synthesis and used as a heterogeneous catalyst for direct synthesis of diphenyl carbonate （DPC） by oxidative carbonylation of phenol. In the reaction system of Pd（C4H2O4）（C4H8N2）0.5/Cu（OAc）2/ tetrabutylammonium bromide/ hydroquinone/ 4A molecular sieves, the effect of reaction temperature, time and CO pressure on catalytic activity were investigated, and the results revealed that the catalyst could catalyze oxidative carbonylation of phenol effectively. Under suitable reaction conditions of T=90℃, t=4 h, p（O2）=0.3 MPa, p（CO）=3.9 MPa and CH2Cl2 as solvent, the turnover number （TON） of diphenyl carbonate can reach about 13.50 （mol-DPC/mol-Pd）, which is higher than the TON for oure PdCl2 under the same reaction conditions.

关键词： diphenyl carbonate synthesis heterogeneous catalyst palladium complex oxidative carbonylation

Effect of Doping Cerium in the Support of Catalyst Pd-Co/Cu-Co-Mn Mixed Oxides on the oxidative carbonylation of Phenol

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Chinese Journal of Chemical Engineering 2009年第3期17卷 401-406页

作者：梁英华郭红霞陈红萍吕敬德张波波 School of Chemical Engineering and Biological Technology Hebei Polytechnic University College of Light Industry Hebei Polytechnic University Tangshan Zhongrun Coal Chemical Co. Ltd.

Effect of doping cerium in the support on the catalytic activity and side product of the reaction in the oxidative carbonylation of phenol to diphenyl carbonate (DPC) over the catalyst Pd-Co/Cu-Co-Mn mixed oxides was studied. The specific surface areas, crystal phase, valency, and content of the element on the surface of the catalysts were determined, and the products were detected by gas chromatograph/mass spectrometry (GC-MS). It is found that the catalyst without Ce shows higher activity than that with Ce, and the yields of DPC for the two cata-lysts can reach 30% and 23%, respectively. However, doping cerium can prevent the formation of 2-hydroxyphenyl benzoate and p-bromophenyl phenyl carbonate.

关键词： diphenyl carbonate oxidative carbonylation doping cerium sol-gel method

Influence of dehydrating agents on the oxidative carbonylation of methanol for dimethyl carbonate synthesis over a Cu/Y-zeolite catalyst

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1059-1063页

作者： Dong-Ho Lee Jiin You Je-Min Woo Jung Yoon Seo Young Cheol Park Jong-Seop Lee Hyunuk Kim Jong-Ho Moon Seung Bin Park Greenhouse Gas Laboratory Korea Institute of Energy Research Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology Energy Material Laboratory Korea Institute of Energy Research

The influence of the dehydration by metal oxides on the synthesis of dimethyl carbonate （DMC） via oxidative carbonylation of methanol was studied. A Cu/Y-zeolite catalyst was prepared by the ion exchange method from CuCl2.2H2O and the commercial NH4-form of the Y type zeolite, The catalyst was characterized by X-ray fluorescence （XRF）, N2 adsorption （BET method）, X-ray diffraction （XRD）, and temperature-programmed de- sorption of ammonia （NH3-TPD） to evaluate its Cu and Cl content, surface area, structure, and acidity. Reaction tests were carried out using an autoclave （batch reactor） for 18 h at 403 K and 5.5 MPa （2CH3OH ＋ 1/2O2 ＋ CO （CH3O）2CO ＋ H2O）. The influence of various dehydrating agents （ZnO, MgO, and CaO） was examined with the aim of increasing the methanol conversion （XMeOH, MeOH conversion）. The MeOH conversion increased upon addition of metal oxides in the order CaO 〉〉 MgO 〉 ZnO, with the DMC selectivity （SDMC） following the order MgO 〉 CaO 〉 ZnO. The catalysts and dehydrating agents were characterized before and after the oxidative carbonylation of methanol by thermogravimetric and differential thermogravimetric （TG/DTG）, and XRD to con- firm that the dehydration reaction occurred via the metal oxide （MO ＋ H2O →M（OH）2）. The MeOH conversion increased from 8.7% to 14.6% and DMC selectivity increased from 39.0% to 53.1%, when using the dehydrating azent CaO.

关键词： Carbon monoxide Zeolite Catalyst Dimethyl carbonate oxidative carbonylation Dehydrating agent

N-Heterocyclic Carbene-Palladium Complex Catalyzed oxidative carbonylation of Amines to Ureas

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Chinese Journal of Chemistry 2007年第8期25卷 1065-1068页

作者：郑书展彭新高刘建明孙伟夏春谷 State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academic of Sciences Lanzhou Gansu 730000 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Palladium carbene shows high efficiency without any promoter on oxidative carbonylation of amines to ureas and a new type of palladium carbene complex containing both an aniline and an NHC ligands was found to be the ... 详细信息

关键词： N-heterocyclic carbene oxidative carbonylation urea

Novel fabrication of copper oxides on AC and its enhanced catalytic performance on oxidative carbonylation of methanol

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Chinese Chemical Letters 2017年第1期28卷 70-74页

作者： Ke Shi Shou-Ying Huang Zhong-Yao Zhang Sheng-Ping Wang Xin-Bin Ma Key Laboratory for Green Chemical Technology School of Chemical Engineering and Technology Tianjin University Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China

Copper oxides（CuOx） nanoparticles dispersed on activated carbon（AC） were prepared by using vaporphase methanol as the reducing agent. The CuOx/AC as prepared exhibited an enhanced catalytic activity in oxidative carbonylation of methanol to dimethyl carbonate（DMC）. The catalytic performance was significantly influenced by reduction conditions including temperature and time. With the similar selectivity of DMC, the space time yield（STY） under optimal reduction conditions reached up to 408 mg g^-1h^-1, which is superior to conventional methods such as thermolysis and solvothermal reduction. Based on the characterization results of XRD, TEM and XPS, the good copper dispersion and high Cu^＋ content obtained by vapor-phase methanol reduction were mainly responsible for the high catalytic activity.

关键词： Dimethyl carbonate oxidative carbonylation Copper oxides Vapor-phase methanol reduction Activated carbon

An Efficient Synthesis of 2-Oxazolidinones by Palladium-catalyzed oxidative carbonylation of β-Aminoalcohols and 2-Aminophenol under Mild Conditions

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Chinese Journal of Chemistry 2005年第5期23卷 643-645页

作者：李福伟彭新高夏春谷胡斌 StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesandGraduateSchooloftheChineseAcademyofSciencesLanzhouGansu73000China

oxidative carbonylation of β‐aminoalcohols and 2‐aminophenol in Pd(OAc) 2 /I 2 catalytic system to produce the corresponding 2‐oxazolidinones was conducted with high yields and selectivities in short reaction time. Mild reaction conditions, high catalytic turnover frequency value, improved yields and selectivities are the remarkable features exhibited by this process.

关键词： oxidative carbonylation β‐aminoalcohol 2‐aminophenol 2‐oxazolidinone catalytic turnover frequency

Selenium-catalyzed oxidative carbonylation of 2-aminobenzyl alcohol to 1, 4-dihydro-2H-3, 1-benzoxazin-2-one

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Selenium-catalyzed oxidative carbonylation of 2-aminobenzyl ...

CuY zeolite supported Pd:a simple and efficient catalytic and dehydrating system for oxidative carbonylation of phenol to diphenyl carbonate

河南省化学会2016年学术年会

作者： Ping Wang Xueli Niu Zhengwei Li Xiaopeng Zhang School of Chemistry and Chemical Engineering Henan Normal University

1,4-Dihydro-2H-3, 1-benzoxazin-2-one is an important structural motif and is widely found in biologically active compounds. For example, efavirenz is a well-known nonnucleoside reverse transcriptase inhibitor and gained attention in the treatment of HIV infections. Others containing this structural motif were found to be orally active nonsteroidal progesterone receptor antagonists which are interesting for the therapy of hormone-dependent cancers. Traditionally, 1,4-dihydro-2H-3, 1-benzoxazin-2-one can be easily prepared by the reaction of 2-aminobenzyl alcohol with phosgene or its substitutes such as chloroformate, triphosgene, urea, and N,N’-carbonyldiimidazole, etc. However, high toxicity of phosgene, low atom economy, and or the emission of the corrosive waste are the main drawbacks associate with this method. Here, an efficient, economical, phosgene-free approach to 1, 4-dihydro-2H-3, 1-benzoxazin-2-one is developed. With cheap and recyclable nonmetal selenium instead of noble metal palladium as the catalyst, carbon monoxide instead of virulent phosgene or its derivatives as the carbonylation agent, oxygen as the oxidant, the selenium-catalyzed oxidative carbonylation reaction of 2-aminobenzyl alcohol can proceed efficiently in one-pot manner in the presence of triethylamine to afford the desired 1, 4-dihydro-2H-3, 1-benzoxazin-2-one in 87% yield. Selenium catalyst can be easily recovered due to its phase-transfer catalytic function and recycled.

关键词： Selenium oxidative carbonylation 1,4-Dihydro-2H-3 1-benzoxazin-2-one 2-Aminobenzyl alcohol Phase-transfer catalysis

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CuY zeolite supported Pd:a simple and efficient catalytic an...