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Chinese Journal of Chemical Engineering 2018年第5期26卷 1064-1070页

作者： Haimin Shen Yan Wang Jinhui Deng Long Zhang Yuanbin She state key laboratory breeding base of green chemistry-synthesis technology College of Chemical Engineering Zhejiang University of Technology

Autoxidation of cycloalkanes （C5-C8） with molecular oxygen under catalyst-free and solvent-free conditions was conducted systematically for the first time, focusing on the autoxidation temperature and product distribution. The autoxidation of cyclopentane, cyclohexane, cycloheptane and cyclooctane occurs at 120 ℃, 130 ℃, 120 ℃, and 105 ℃ respectively, with obvious oxidized products formation. At 140 ℃, 145 ℃, 130 ℃ and 125 ℃, acceptable yields of the oxidized products could be obtained for them, and the oxidized product distributions were investigated in detail. The autoxidation of cycloalkanes follows the pseudo-first-order kinetic model and the apparent activation energies （Ea） for the autoxidation of cyclopentane and cyclohexane are 159.76 kJ. tool-1 and 86.75 kJ. mol-1 respectively. This study can act as an important reference in screen of suitable reaction temperature and comparison of the performance of various catalysts in the catalytic oxidation of cycloalkanes in the attempt to enhance the oxidized product selectivity.

关键词： Cycloalkane Oxidation Autoxidation temperature Product distribution

The ligand coordination approach for improving the stability of low-mercury catalyst in the hydrochlorination of acetylene

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1217-1221页

作者： Xiaolong Xu Haihua He Jia Zhao Bailin Wang Shanchuan Gu Xiaonian Li Institute of Industrial Catalysis of Zhejiang University of technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

Mercuric chloride supported on activated carbon(HgCl_2/AC) is used as an industrial catalyst for the hydrochlorination of acetylene. Loss of HgCl_2 by sublimating from the surface of activated carbon causes the irreversible deactivation of mercury catalyst and environmental pollution. In this work, a ligand coordination approach based on the Principle of Hard and Soft Acids and bases(HSAB) was employed to design more stable lowmercury catalyst. The low-mercury catalysts(4% HgCl_2 loading) were prepared by using HgCl_2 and potassium halides(KX, X = Cl, I) as precursors. The HgCl_2-4KI/AC catalyst showed best catalytic stability than HgCl_2/AC and HgCl_2-4KCl/AC in the hydrochloriantion of acetylene. HgCl_2 could form more stable complex with KI,K_2HgI_4 as the main active component of the HgCl_2-4KI/AC catalyst. The characterizations of XRD and EDX analysis illustrated that the active component of HgCl_2-4KI/AC was highly dispersed on the surface of activated *** sublimation rates of HgCl_2 from the catalysts verified that the active component with larger stability constant had better thermal stability. Using Hg(Ⅱ) complexes with high stability constant as the active component may be the research direction of developing highly stable low-mercury catalyst for the hydrochlorination of acetylene.

关键词： Low-mercury catalyst Sublimation K2HgI4 Ligand coordination Acetylene hydrochlorination

Sodium tetrachloroaurate(III) dihydrate-catalyzed efficient synthesis of 1,5-benzodiazepine and quinoxaline derivatives

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第2期11卷 102-108页

作者： Ren-xin SHI Yun-kui LIU Zhen-yuan XU state key laboratory breeding base of green chemistry-synthesis technology Zhejiang University of Technology Hangzhou 310014 China

Both 1,5-benzodiazepine and quinoxaline derivatives are important heterocycles in pharmaceuticals. We describe an efficient and clean method for the synthesis of 1,5-benzodiazepines from o-phenylenediamine and ketones catalyzed by sodium tetrachloroaurate（Ⅲ） dihydrate under mild conditions. The catalyst was shown to be equally effective for the synthesis of quinoxalines from o-phenylenediamine and α-bromo ketones under the similar reaction conditions. This method produced good yields.

关键词： 1,5-benzodiaepines o-phenylenediamine Ketones Quinoxalines Gold catalyst

Facile and efficient one-pot synthesis of 2-arylbenzoxazoles using hydrogen tetrachloroaurate as catalyst under oxygen atmosphere

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第6期10卷 472-478页

作者： Yun-kui LIU Da-jie MAO Shao-jie LOU Jian-qiang QIAN Zhen-yuan XU state key laboratory breeding base of green chemistry-synthesis technology Zhejiang University of Technology Hangzhou 310014 China

In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-arylbenzoxazoles, which were directly synthesized from 2-aminophenol and aldehydes catalyzed by hydrogen tetrachloroaurate (HAuCl4·4H2O) under an oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant.

关键词： 2-Arylbenzoxazoles 2-Aminophenol Aldehydes Hydrogen tetrachloroaurate One-pot synthesis

Dynamic Mechanical Behavior of a Novel Polymeric Composite Damping Material

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Chinese Chemical Letters 2005年第11期16卷 1527-1530页

作者： Cheng ZHANG Jiang Feng SHENG Chun An MA state key laboratory breeding base for green chemistry synthesis technology Zhejiang University of Technology Hangzhou 310032

The dynamic mechanical behavior of a novel polymeric composite damping material has been investigated in this article. The composite consists of chlorinated polyethylene （CPE）, N,N-dicyclohexyl-2-benzothiazolylsufenamide （DZ）, 4,4＇-thio-bis（3-methyl-6-tert-buthylphenol）（BPSR） and vapor-grown carbon fiber （VGCF）. It is found that either the position or the intensity of damping peak can be controlled by changing the composition of CPE/DZ/BPSR composite. Within a certain composition region, damping peak maximum depends on CPE/DZ ratio, whereas damping peak position is controlled by BPSR content. Moreover, the improvement of storage modulus can be achieved by incorporation of VGCF. These results may imply that a damping material possessing both good damping properties and high strength can be designed and obtained.

关键词： Dynamic mechanical behavior polymeric composite damping material.

High halogenated nitrobenzene hydrogenation selectivity over nano Ir particles

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Chinese Journal of Chemical Engineering 2017年第3期25卷 306-312页

作者： Lei Ma Jianguo Wang Hanbing Wang Qunfeng Zhang Chunshan Lu Xiaobo He Xiaonian Li Industrial Catalysis Institute of Zhejiang University of technology State Key Laboratory Breeding Base of Green Chemistry Synthesis TechnologyHangzhou 310032China

The selective hydrogenation of halogenated nitrobenzene over noble metal catalysts(Pd, Pt, and Ir) has attracted much attention owing to its high efficiency and environmental friendliness. However, the effect of size on the catalytic performance varies among different metal catalysts. In this study, sub-nano(<3 nm) Ir and Pd particles were prepared, and their catalytic properties for hydrogenation of halogenated nitrobenzene were *** show that high selectivity(N 99%) was achieved over small Ir nanoparticles, in which the selectivity over the Pd with same size was much lower than that on Ir nanoparticles. Meanwhile, Ir and Pd have different hydrogen consumption rates and reaction rates. Density functional theory calculations showed that p-chloronitrobenzene(CNB) has different adsorption properties on Ir and Pd. The distance between oxygen(cholorine) and Ir is much shorter(longer) than that between oxygen and Pd. The reaction barriers of dechlorination of p-CNB and p-chloroaniline over different Ir models are much larger than those on Pd. Especially,lower coordination of Ir leads to larger barriers of dechlorination reaction. These theoretical results explain the difference between Ir and Pd on hydrogenation of halogenated nitrobenzene.

关键词： Halogenated nitrobenzene Selective hydrogenation Sub-nano lr Density functional

Influence of the post-treatment of HZSM-5 zeolite on catalytic performance for alkylation of benzene with methanol

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1777-1783页

作者： Qingtao Wang Wenwen Han Hualei Hu Jinghui Lyu Xiaolong Xu Qunfeng Zhang Hongjing Wang Xiaonian Li Institute of Industrial Catalysis of Zhejiang University of technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Hangzhou 310032 China

The porous material HZSM-5 zeolite with micro-mesopore hierarchical porosity was prepared by post-treatment （combined alkali treatment and acid leaching） of parent zeolite and its catalytic performance for benzene alkylation with methanol was investigated. The effect of post-treatment on the textural properties was characterized by various techniques （including ICP-AES, XRD, nitrogen sorption isotherms, SEM, NH3-TPD, Py-IR and TG）. The results indicated that the post-treatment could modify the structural and acidic properties of HZSM-5 zeolite. In this procedure, not only additional mesopores were created by selective extraction of silicon but also the acidity was tuned. Consequently, the modified HZSM-5 zeolite showed larger external surface area with less acid sites as compared to the parent zeolite. It was found out that the modified zeolite exhibited a higher benzene conversion and xylene selectivity for alkylation of benzene with methanol as well as excellent life span of the catalyst than conventional ones. This can be explained by the facts that the presence of additional mesopores improved the diffusion property in the reactions. Furthermore, the modified zeolite showed an appropriate Bronsted acidity for effective suppression of the side reaction of methanol to olefins, thus reduced the accumulation of coke on the HZSM-5 zeolite, which was favorable for the catalyst stability. In comparison with the parent HZSM-5 zeolite, the modified zeolite by alkali treatment and acid leaching showed better performance for the benzene alkylation with methanol.

关键词： HZSM-5 zeolite Hierarchical porosity Post-treatment Benzene alkylation with methanol

Pt-Ni core-shell structure with Pt-skin and electronic effect on catalytic performance

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Chinese Journal of Chemical Engineering 2023年第11期63卷 260-267页

作者： Chong Yao Dandan Ma Jie Luo Yixin Chen Min Tian Haoxuan Xie Chunshan Lu Feng Feng Xiaoliang Xu Qingtao Wang Qunfeng Zhang Xiaonian Li state key laboratory breeding base of green chemistry synthesis technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

In order to improve the catalytic performance of the nitrobenzene hydrogenation rearrangement to prepare p-aminophenol,a bimetallic Pt-Ni/C(PNC)catalyst was *** advantage of the synergistic effect of Ni and Pt to enhance product selectivity and catalytic performance stability,the electrons in Ni are moved to Pt by the electron effect,which affects the catalyst’s ability to activate H_(2)as well as the amount of hydrogen ***,due to the strong Pt(5d)-Ni(3d)coupling effect,Ni can effectively maintain Pt stability in the acidic system and reduce Pt *** stability of the PNC can be found to be greatly enhanced compared to the Pt/C(PC)catalyst,and p-aminophenol selectivity is greatly enhanced,showing excellent catalytic performance.

关键词： Nitrobenzene p-Aminophenol Pt-Ni/C bimetallic catalyst Electronic effect Pt(5d)-Ni(3d)coupling

Preparation and properties of a silver particle-coated and 1-dodecanethiol-modified superhydrophobic melamine sponge for oil/water separation

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Frontiers of Chemical Science and Engineering 2022年第8期16卷 1237-1246页

作者： Xiaofei Sun Shijie Feng Zhe Zhang Pengyu Zhang Jiefeng Zhao Yunling Gao Junxian Yun state key laboratory breeding base of green chemistry synthesis technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310032China

A Ag particle-coated and 1-dodecanethiolmodified melamine sponge(Ag-DDT-MS)was prepared through surface roughness by coating silver particles and subsequent grafting of a hydrophobic long hydrocarbon *** and 3D porous Ag-DDT-MS was characterized by Fourier transform infrared spectroscopy,scanning electron microscope,energy-dispersive X-ray spectroscopy,and X-ray *** water contact angle of Ag-DDT-MS reached 159.2°.Ag-DDT-MS exhibited excellent absorption capacity for high viscous oils and organic solvents,ranging from 42.8 to 105.2 g∙g−*** absorbed oils can be easily collected by the mechanical pressing process,and the oil recovery rate was satisfactory,more than 90%after 20 ***-DDT-MS material also demonstrated good stability and excellent compressionrecovery ability,keeping 88.6%of the initial height after ten compression-release cycles.

关键词： melamine sponge oil-absorbing material,hydrophobic oil-water separation oil absorption capacity

Regulation of the selective hydrogenation performance of sulfur-doped carbon-supported palladium on chloronitrobenzene

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Chinese Journal of Chemical Engineering 2023年第6期58卷 69-75页

作者： Qunfeng Zhang Bingcheng Li Yuan Zhou Deshuo Zhang Chunshan Lu Feng Feng Jinghui Lv Qingtao Wang Xiaonian Li Institute of Industrial Catalysis of Zhejiang University of technology State Key Laboratory Breeding Base of Green Chemistry Synthesis TechnologyHangzhou 310014China

The overall performance of metal catalysts can be efficiently adjusted by modifying carbon carriers with different valence sulfur *** wet impregnation technique successfully prepared carbon material carriers doped with varying sources of sulfur(Na_(2)SO_(4),NaHSO_(3),Na_(2)S·9H_(2)O).Palladium carbon catalysts doped with different sulfur precursors had been prepared with the aid of the liquid-phase reduction method of the selective hydrogenation of o-chloronitrobenzene(o-CNB)to o-chloroaniline(o-CAN).The catalyst prepared for Na_(2)S·9H_(2)O as a precursor has excellent performance,and the selectivity for o-CAN is more than 99.9%at 100%*** addition,the characterization results show that with the decrease of S valence,the electronic effect between S and Pd increases,and the outer electron shift of Pd increases,which reduces the adsorption and dissociation ability of Pd to hydrogen,resulting in excellent *** effects provided a good idea for the hydrogenation of o-CNB and a different point of view on sulfur doping in a variety of hydrogenation reactions.

关键词： Catalyst Hydrogenation Selectivity Sulfur doping Electronic effect