共查询到18条相似文献,搜索用时 67 毫秒
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以2-(2-吡啶基)咪唑(pIM)、Co2+和NaVO3为原料,在水热条件下,制备了新的钒氧簇化合物[Co(pIM)V2O6] (1)。采用X射线单晶衍射、粉末X射线衍射、傅里叶变换红外光谱和元素分析等方法对化合物进行了表征。单晶解析表明,该化合物由VO4四面体和CoO3N2四方锥通过氧原子共边、共角连接成二维结构。基于钒氧簇在催化氧化体系中的高效活性,1作为非均相反应的催化剂,在以H2O2为氧化剂的催化烯烃环氧化反应中表现出优秀的催化性能,催化剂能够多次重复使用且活性基本保持不变。此外,磁化率研究表明1中存在反铁磁相互作用。 相似文献
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以2-(2-吡啶基)咪唑(pIM)、Co2+和NaVO3为原料,在水热条件下,制备了新的钒氧簇化合物[Co (pIM) V2O6](1)。采用X射线单晶衍射、粉末X射线衍射、傅里叶变换红外光谱和元素分析等方法对化合物进行了表征。单晶解析表明,该化合物由VO4四面体和CoO3N2四方锥通过氧原子共边、共角连接成二维结构。基于钒氧簇在催化氧化体系中的高效活性,1作为非均相反应的催化剂,在以H2O2为氧化剂的催化烯烃环氧化反应中表现出优秀的催化性能,催化剂能够多次重复使用且活性基本保持不变。此外,磁化率研究表明1中存在反铁磁相互作用。 相似文献
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本文合成了六种呋喃甲醛碱锰金属配合物-双(呋喃甲醛)缩邻苯二胺合锰(Ⅱ)(1),双(呋喃甲醛)缩乙二胺合锰(Ⅱ)(2),双(呋喃甲醛)缩1,3-丙二胺合锰(Ⅱ)(3),双(呋喃甲醛)缩1,2-环己二胺合锰(Ⅱ)(4),双(呋喃甲醛)缩1,2-丙二胺合锰(Ⅱ)(4),双(呋喃甲醛)缩二乙烯三胺合锰(Ⅱ)(6),并用元素分析,红外光谱和核磁共振谱加以表征,以这些配合物作为仿加氧酶的模型化合物催化环氧化苯乙烯,环己烯,2-辛烯,并讨论了配体结构,底物结构对催化环氧化的影响。 相似文献
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过氧化氢为氧源催化烯烃环氧化研究 总被引:2,自引:0,他引:2
环境友好催化烯烃环氧化是催化氧化领域中的一大热点,过氧化氢作为一种理想的清洁氧源日益受到人们的重视。本文从匀相和多相催化两方面综述了近年来以过氧化氢为氧源催化烯烃环氧化研究的主要进展,对一些有很好工业化应用前景的反应体系作了详细介绍。 相似文献
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催化分子氧环氧化烯烃的研究进展 总被引:3,自引:0,他引:3
环氧化合物是一类十分有用的合成中间体 ,广泛应用于石油化工、精细化工和有机合成 .但至今为止 ,工业上除用分子氧直接氧化乙烯制环氧乙烷外 ,其它所有 C2 以上的环氧化合物还不能用分子氧直接氧化相应的烯烃制得 .国外生产环氧丙烷和环氧氯丙烷的主要方法有卤醇法、Halcon法 ,而国内则以卤醇法为主 .另外 ,过酸法常用于精细产品的合成中 ,以 H2 O2 、Na Cl O等为氧源的环氧化研究 ,近年来也已取得了较大的进展 .卤醇法较早应用于生产 ,但存在严重的设备腐蚀和环境污染问题 ;Halcon法利用 ROOH为氧源 ,有联产品 ,生产过程较复杂 ,基本… 相似文献
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采用离子交换法制备了铜掺杂多孔氧化镍(Copper-doped NiO)非均相催化材料;通过扫描电子显微镜、X射线衍射、傅里叶变换红外光谱和热重分析对其形貌和结构进行了表征.结果表明, Copper-doped NiO呈均匀的片状花形结构分布,其晶体结构与NiO的晶体结构相同,Copper-doped Ni-MOF稳定性比Ni-MOF好.以苯甲醇催化氧化反应为探针反应,对Copper-doped NiO的催化性能进行测试,结果表明,苯甲醇的转化率高达99%,苯甲醛的选择性为99%,且该催化材料在循环5次后具有良好的循环稳定性. 相似文献
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通过多步接枝法将双吡啶-甲基三氧化铼配合物负载到MCM-41上,获得多相化的甲基三氧化铼催化剂.通过傅里叶变换红外光谱、紫外-可见漫反射光谱、元素分析、原子吸收、X-光射线衍射以及氮气吸附等方法对负载催化剂进行了表征.将其用于过氧化氢、尿素过氧化氢络合物环氧化环己烯、苯乙烯以及1-辛烯的催化剂,显示很高的催化活性和环氧化物选择性,但循环使用性能较差. 相似文献
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Qingnan Feng Xinlu Wang Huan Zhang Jinxian Wang Guixia Liu Wensheng Yu Xiangting Dong 《中国化学会会志》2020,67(11):2012-2018
CoMoO4 has attracted extensive interest as an anode for lithium-ion batteries due to its high theoretical capacity and low cost. Nevertheless, achieving controlled synthesis of CoMoO4 with definite morphology by simply adjusting a certain synthesis condition is a very meaningful topic. Here, rod-like CoMoO4 formed by lamellar stacking was successfully synthesized through the control pH value of one-step hydrothermal route, and its excellent electrochemical performance was investigated. The rod-like CoMoO4 prepared at 190°C and pH = 7 has a high initial discharge capacity of 1,482.8 mAh/g at 200 mA/g. The discharge capacity of 1,041 mAh/g was maintained after 500 cycles, and the capacity retention was 70.2%. The improved electrochemical performance of rod-like CoMoO4 can be attributed to the rod structures, which could shorten ion diffusion and electronic conduction pathway, provide more efficient charge storage sites, and alleviate the volume changes during Li + intercalation/deintercalation. 相似文献
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Mahdi Mirzaee Bahram Bahramian Parichehr Gholampour Samaneh Teymouri Toktam Khorsand 《应用有机金属化学》2019,33(4)
Fe3O4 core nanoparticles were prepared via a solvothermal process, and then they were covered with a surface hydroxyl‐rich boehmite shell via the hydrothermal‐assisted sol–gel processing of aluminum 2‐propoxide. The outer surface of the boehmite shell was subsequently covalently functionalized with 3‐(tri‐methoxysilyl)‐propylamine or 3‐(tri‐methoxysilyl)‐propyl chloride, and the terminal chlorine groups were treated with imidazole. These compounds were used to support the hexa‐carbonyl molybdenum and oxo‐sulfato vanadium (IV) complexes. The supported catalysts were characterized by the FT‐IR, CHN, ICP, and TEM analysis techniques. They were then used in the epoxidation of cis‐cyclooctene. The catalytic procedures were optimized for different parameters such as the solvent, oxidant, and temperature. The reaction progress was investigated by the gas–liquid chromatography analysis. The catalysts used were simply recovered from the solution by applying a magnet, and recycling the experiments revealed that the heterogeneous nanocatalysts could be repeatedly used for the epoxidation of cis‐cyclooctene. The optimized conditions were also successfully used for the epoxidation of some other alkenes. 相似文献
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Schiff碱及其配合物在治疗肿瘤、抗菌、仿生载氧等方面具有优异的性能,在催化领域中也表现出多种性质。本文合成了三种结构简单的Schiff碱配体以及它们的过渡金属配合物,并研究了其对环己烯的催化环氧化性能。配体的结构如下。 相似文献
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WANG Wei WANG Tao FAN Xuecheng ZHANG Cuilin HU Jinxing CHEN Hui FANG Zhenxing YAN Jiefeng LIU Bing 《高等学校化学研究》2019,35(2):261-270
A facile and green freeze-drying-assisted method was proposed to synthesize C0MoO4 mesoporous nano-sheets(MPNSs).The resulting product exhibits a Mgh specific capacity and good rate perfomance when evalimte an anode material for lithium-ion batteries(LIBs).The reversible specific capacity can be kept at 1105.2 mA·h·g^-1 after 100 cycles at a current density of 0.2 A/g.Even at the current densities of 1 and 4 A/gs the CoMoO4 MPNSs electrode can still retain the reversible capacities of 1148.7 and 540 mA·h·g^-1,respectively.Furthermore,the full cell(LiPePO4 catliode/CoMoO4 MPNSs anode)displays a stable discharge capacity of 146.7 mA·h·g^-1 at 0.1 C(1 C=170 mA/g)together with an initial coulombic efficiency of 98.2%.In addition,the CoMoO4 crystal structure is destroyed and reduced into Co^0 and Mo^0 in the first discharge process.In the subsequent cycles,the attractive Li storage properties come from the reversible conversions between Co/Co^2+and Mo/Mo^6+.The improved electroche-mical performance of CoMoO4 MPNSs is mainly attributed to their unique porous structures,which not only possess a good ion diffusion and electronic conduction pathway,but also provide many cavities to alleviate the volume changes during repeated cycling.This work offers a new perspective to the design of other porous electrode materials with a good energy storage performance. 相似文献
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环氧苯乙烷具有重要的经济价值,现有的工业生产技术存在能耗高及环境污染大等诸多问题,使得环境友好的苯乙烯环氧化生产工艺的开发具有重要意义.采用一步合成法制备了系列金-硅胶纳米球催化剂,实现了纳米金的高度分散(粒径6.4 nm),对苯乙烯环氧化反应表现出较好的催化活性及产物选择性.通过X射线粉末衍射、红外光谱及X射线光电子能谱等表征技术,结合苯乙烯环氧化反应性能的考察,对金-硅胶催化剂的制备条件进行了优化. 相似文献
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Feng-Lan Chai Xiang-Yu Wang Jing-Chao Tao 《Reaction Kinetics and Catalysis Letters》2009,96(1):139-146
A novel dioxomolybdenum(VI) complex of ferrocenyliminoalcoholate was easily prepared by the reaction of the ferrocenyl-containing
iminoalcohol and MoO2Cl2 (THF)2 using THF as solvent. The sample was characterized by FT-IR, 1
H NMR, elemental analysis and UV-Vis. The complex exhibited an efficient, selective catalytic performance for styrene and cyclohexene epoxidation. 相似文献