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摘要：<正>《催化学报》是中国化学会催化学会会刊,由中国化学会和中国科学院大连化学物理研究所主办,科学出版社与Elsevier出版社出版,月刊.报道催化领域基础性和应用基础性最新研究成果.《催化学报》目前发表的所有文章均被SCI收录,其中所有英文文章还同时被EI收录.《催化学报》2012年SCI影响因子为1.304,2011年国内(中国科学技术信息研究所)影响因子为1.288.微流控技术制备微胶囊负载钯催化剂
摘要：采用微流控技术结合悬浮聚合方法实现了百微米级含膦配体聚苯乙烯微胶囊的可控制备, 微胶囊尺寸在320～420 μm范围内可调, 且单分散性好. 扫描电子显微镜、能量散射光谱和电感耦合等离子发射光谱结果证实了其形貌和组成的均匀性及钯负载的可控性和有效性. 以溴代芳烃与苯硼酸的Suzuki偶联反应为模型反应评价了负载Pd(PPh3)4的百微米级微胶囊的催化性能, 发现其性能与文献报道的7～8 μm的同类催化剂微胶囊接近, 且均优于均相催化剂; 该催化剂经简单过滤后, 可实现多次循环使用, 未发现活性物种的流失. 该法实现了连续制备, 因而有助于提高制备的效率和可控性. 另外, 所制百微米级催化剂微胶囊在固定床反应器内具有较高催化剂浓度和机械性能, 且优于浆态床中使用的微米级催化剂微胶囊.基于C-H键活化的铜催化二苄胺氧化酰胺化反应(英文)
摘要：基于铜催化的C-H键活化构建了一类高效的二苄胺氧化酰基化生成N-苄基苯甲酰胺的反应. 该反应使用CuBr作为催化剂,二乙酸碘苯作为氧化剂, 在温和条件下生成两种酰胺, 总产率最高可达92.0%. CuBr催化剂价廉易得, 催化活性高. 同时这也是首次使用二乙酸碘苯作为氧化剂, 通过二苄胺的直接氧化酰基化反应合成N-苄基苯甲酰胺.水相中底物促进的铜催化氨基醇N-芳基化反应(英文)
摘要：在水相体系中, 利用铜催化一系列氨基醇类底物(1.2 mmol)与碘代芳烃(1.0 mmol)进行N-芳基化反应. 由于氨基醇具有双齿配位及相转移催化能力, 该反应利用氨基醇类底物自身的促进作用, 在不使用外加配体与相转移催化剂的温和条件下以高收率获得了氨基醇N-芳基化产物(64% 93%).稻壳炭基固体酸催化剂的制备及其催化酯化反应性能
摘要：以热解稻壳炭为原料,浓硫酸为磺化剂制备了固体酸催化剂.采用X射线衍射、X射线光电子能谱、元素分析、孔结构分析和热重-质谱联用等手段对其进行了表征.以油酸和甲醇的酯化为探针反应,考察了磺化温度和时间对催化剂活性的影响,探讨了反应条件对油酸转化率的影响,并对所制催化剂的稳定性进行了研究.结果表明,制备该催化剂的适宜磺化温度和时间分别为90℃和0.25h,在该条件下制得的催化剂为无定形碳结构,磺酸基密度为0.7mmol/g.该催化剂表现出较高的催化酯化反应活性,在催化剂用量为5%、甲醇/油酸摩尔比为4、酯化温度和时间分别为110℃和2h的条件下,油酸的酯化率可达98.7%.该催化剂具有较好的稳定性,经7次连续反应后,油酸的酯化率仍可达96.0%.无溶剂条件下离子液体催化香豆素衍生物的绿色合成(英文)
摘要：Brnsted acidic ionic liquids, namely 2-pyrrolidonium hydrogen sulfate, N-methyl-2-pyrrolidonium hydrogen sulfate, N-methyl-2-pyrrolidonium dihydrogen phosphate, (4-sulfobutyl)tris(4-sulfophenyl)phosphonium hydrogen sulfate, and triphenyl(propyl-3-sulfonyl)phosphonium toluenesulfonate, catalyzed efficient Pechmann condensation of phloroglucinol with β-keto ethyl/ methyl esters. 5,7-Dihydroxy-4-methylcoumarin and 5,7-dihydroxy-4-phenylcoumarin were prepared in good to excellent yields under mild, ambient, and solvent-free conditions. Pyrano[2,3-h] coumarins were then prepared by one-pot three-component reactions of 5,7-dihydroxy-4-subsituted coumarin, malononitrile, and aldehydes in the presence of catalytic amounts of Br nsted basic ionic liquids, namely 2-hydroxyethylammonium formate, 3-hydroxypropanaminium acetate, 1-butyl-3-methylimidazolium hydroxide, pyrrolidinium formate, and pyrrolidinium acetate, under thermal solvent-free conditions. The catalysts are environmentally benign and can be easily prepared, stored, and recovered without significant loss of activity.铁酸钴纳米粒子:室温下点击合成亚芳基巴比妥酸衍生物的高效可磁性分离多相催化剂(英文)
摘要：A coprecipitation method was used to synthesize superparamagnetic CoFe2O4 nanoparticles without using any capping agents/surfactants. The prepared nanoparticles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, a vibrating sample magnetometer (VSM), N2 adsorption and thermogravimetric/differential thermal analysis/differential thermal gravimetry techniques. The synthesized spinel CoFe2O4 nanoparticles had an average size of 2-8 nm with a high surface area (140.9 m2/g). The field-dependent magnetization, demonstrated by VSM and saturation magnetization, was found to be 1.77 emu/g. An efficient method was used for the synthesis of arylidene barbituric acid derivatives using CoFe2O4 magnetic nanoparticles as a magnetically separable and reusable catalyst in aqueous ethanol. The attractive features of this synthetic protocol were very short reaction time, high yields, high turnover frequency, simple work-up procedure, economy, a clean reaction methodology, and chemoselectivity, as well as provision of an ecofriendly and green synthesis.Cu-ZnO催化剂上水活化的第一性原理研究(英文)
摘要：采用密度泛函理论计算研究了水在Cu-ZnO催化剂表面上不同位点的解离过程. 结果发现, 水在纯Cu密堆积面和台阶面解离能垒都较高; 而在负载的ZnO薄膜上, 由于水解离过程能垒较低并且反应约为热中性, 水将会在表面上部分解离并达到动力学平衡. Cu-ZnO界面被确定为水解离的活性中心. 水解离后产生的H原子和羟基均可以较大吸附能吸附在界面处, 并且界面处的类似台阶结构大大降低了解离能垒, 从而使得水的解离可自发进行. 另外, H原子和羟基在ZnO薄膜表面可以较低的能垒扩散, 因此水解离活性位点可以持续催化后续解离过程. 该结果深化了对水在Cu-ZnO催化剂表面活化过程的认识.碱性介质中多孔纳米结构镍/钯-镍电极上甲醇电氧化反应(英文)
摘要：A nanostructured Ni/Pd-Ni catalyst with high activity for methanol oxidation in alkaline solution was prepared by electrodeposition followed by galvanic replacement, that is, electrodeposition of Ni-Zn on a Ni coating with subsequent replacement of the Zn by Pd at the open circuit potential in a Pd-containing alkaline solution. The surface morphology and composition of the coatings were examined by energy dispersive X-ray spectroscopy and scanning electron microscopy. The Ni/Pd-Ni coatings were porous and were composed of discrete Pd nanoparticles of about 58 nm. The electrocatalytic activity of the Ni/Pd-Ni electrodes for the oxidation of methanol was examined by cyclic voltammetry and electrochemical impedance spectroscopy. The onset potentials for methanol oxidation on Ni/Pd-Ni were 0.077 V and 0.884 V, which were lower than those for flat Pd and smooth Ni electrodes, respectively. The anodic peak current densities of these electrodes were 4.33 and 8.34 times higher than those of flat Pd (58.4 mA/cm2 vs 13.47 mA/cm2) and smooth Ni (58.4 mA/cm2 vs 7 mA/cm2). The nanostructured Ni/Pd-Ni electrode is a promising catalyst for methanol oxidation in alkaline media for fuel cell application.氢分离与CO催化甲烷化双功能型钯复合膜
摘要：以多孔Al2O3陶瓷为基体材料,采用浸渍法担载NiO后用2B铅笔修饰NiO/Al2O3表面,通过化学镀法沉积约5μm厚的金属钯,还原后成功制得Pd/Pencil/Ni/Al2O3膜.为进行对比,还制备了未担载镍的Pd/Pencil/Al2O3膜.膜的表面和断面形貌分别采用扫描电镜和金相显微镜观测,膜的透氢动力学通过H2/N2单气体法测试,并以成分为H277.8%,CO5.2%,CO213.5%和CH43.5%的原料氢测定了膜的氢分离效果.结果表明,未载镍的Pd/Pencil/Al2O3膜只具有氢分离作用,而Pd/Pencil/Ni/Al2O3膜还可以有效地将钯膜泄漏的CO和CO2转化为甲烷,因而成为双功能型钯膜.这种双功能膜尤其适用于面向质子交换膜燃料电池(PEMFC)的氢气分离,既有效解决了PEMFC对氢燃料中CO格外敏感的难题,又提高了对钯膜缺陷的容忍度,因而延长了钯膜的使用寿命.淀粉基炭负载纳米铜催化合成碳酸二甲酯
摘要：以硝酸铜和可溶性淀粉为原料,经过溶胶-凝胶化过程、高温炭化和KOH活化得到炭负载铜催化剂(Cu/C),采用扫描电镜、透射电镜、X射线衍射、热重-差热分析仪、N2吸附和CO程序升温脱附对催化剂结构进行了表征,并考察了它在甲醇氧化羰基化合成碳酸二甲酯(DMC)反应中的催化活性.结果表明,活化温度和KOH用量对催化剂的表面结构及金属铜粒子尺寸影响显著,当活化温度为850℃,KOH:C=1(质量比)时,Cu/C催化剂的比表面积达到1690m2/g,铜纳米粒子平均晶粒尺寸为30.4nm,催化活性最高,DMC时空收率达到235.7mg·g-1·h-1,甲醇转化率和DMC选择性分别为1.6%和76.5%.载体表面氧化程度对Ni/SiC甲烷化催化剂性能的影响
摘要：采用等体积浸渍法制备了Ni/SiC甲烷化催化剂,研究了SiC载体表面氧化程度对催化剂低温活性和高温稳定性的影响,并采用热重-差示扫描量热、N2物理吸附、傅立叶变换红外光谱、氨程序升温脱附、X射线衍射、氢程序升温还原和氢化学吸附技术对样品进行了表征.结果表明,随着载体氧化温度的提高,催化剂的比表面积和镍分散度降低,但还原性和反应稳定性提高.未氧化载体所负载催化剂的高温稳定性最差,其原因在于载体对镍粒子的固定作用最弱.负载于500和700℃处理的SiC载体上的催化剂具有较好的低温活性和高温稳定性,这是因为适度氧化后的载体能较好地分散并固定镍粒子.900℃处理的载体因过度氧化形成了低活性的氧化层,使负载的镍粒子变大,因而催化剂的低温活性最差.小麦秸秆发酵产生的真菌Pleurotus ostreatus IBL-02锰过氧化物酶的溶胶-凝胶固定化及其催化污水脱色(英文)
摘要：Solid state bio-processing of wheat straw was carried out through an indigenous fungal strain Pleurotus ostreatus IBL-02 under pre-optimized fermentation conditions. The maximum activity, 692±12 U/mL, of the industrially important manganese peroxidase (MnP) enzyme was recorded after five days of still culture incubation. The crude MnP was 2.1-fold purified with a specific activity of 860 U/mg after purification on a Sephadex-G-100 gel column. On native and SDS-PAGE electrophoresis gels, the purified MnP fraction was a single homogenous band of 45 kDa. An active fraction of MnP was immobilized using hydrophobic sol-gel entrapment comprising tetramethoxysilane (T) and propyltrimethoxysilane (P) at different T:P molar ratios. Characterization revealed that after 24 h incubation at varying pH and temperatures, the MnP fraction immobilized at a T:P ratio of 1:2 in the sol-gel retained 82% and 75% of its original activity at pH4 and 70 ℃, respectively. The optimally active fraction at a 1:2 T:P ratio was tested against MnSO4 as a substrate to determine the kinetic catalytic constants KM and Vmax . To explore the industrial applicability of P. ostreatus IBL-02 MnP, both the free and immobilized MnP were used for the decolorization of four different textile industrial effluents. A maximum of 100% decolorization was achieved for the different textile effluents within the shortest time period. A lower KM , higher Vmax , hyper-activation, and enhanced acidic and thermal resistance up to 70 ℃ were the novel catalytic features of the sol-gel immobilized MnP, suggesting that it may be a potential candidate for biotechnological applications particularly for textile bioremediation purposes.溶胶-凝胶新方法合成介孔铁酸铜纳米粉体催化剂上CO低温氧化(英文)
摘要：Mesoporous CuFe2O4 solid solution nanopowders with high specific surface areas were synthesized by a novel, very simple and inexpensive sol-gel route using propylene oxide as gelation agent, and used as the catalyst in low temperature CO oxidation. The samples were characterized by X-ray diffraction, N2 adsorption-desorption, thermogravimetric/differential thermal analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and temperature-programmed reduction. The results revealed that the samples have a nanocrystalline structure with crystals in the range of 10 to 25 nm, and that all the catalysts have mesoporous pores. The addition of Cu into iron oxide affected its structural and catalytic properties. The sample containing 15 mol% Cu showed the highest specific surface area and catalytic activity, and showed high catalytic stability in low temperature CO oxidation.用对氨基苯酚改性的碳纳米管糊电极同时测定羟胺和苯酚(英文)
摘要：A carbon paste electrode that was chemically modified with multiwall carbon nanotubes and p-aminophenol was used as a selective electrochemical sensor for the simultaneous detection of hydroxylamine (HX) and phenol. Cyclic voltammetry, double potential-step chronoamperometry, square wave voltammetry (SWV), and electrochemical impedance spectroscopy were used to investigate the use of p-aminophenol in the carbon nanotubes paste matrixes as a mediator for the electrocatalytic oxidation of HX and phenol in aqueous solution. The coefficient of electron transfer and catalytic reaction rate constant were determined using the electrochemical methods. Under optimized conditions, the electrocatalytic oxidation current peaks for HX and phenol increased linearly with concentration in the range of 0.5-180.0 and 10.0-650.0 μmol/L for HX and phenol, respectively. The detection limits for HX and phenol were 0.15 and 7.1 μmol/L, respectively. The anodic potential peaks of HX and phenol were separated by 0.65 V in SWV. Because of good selectivity and sensitivity, the present method provides a simple method for the selective detection of HX and phenol in practical samples such as water samples.含环氧基团的聚合物微球固载2,2,6,6-四甲基哌啶氮氧自由基催化剂的制备及其催化分子氧氧化苯甲醇
摘要：以甲基丙烯酸缩水甘油酯(GMA)为单体,以乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,采用悬浮聚合法制得交联聚甲基丙烯酸缩水甘油酯(CPGMA)微球,然后以4-羟基-2,2,6,6-四甲基哌啶氮氧自由基(4-OH-TEMPO)为试剂,使CPGMA微球表面的环氧基团发生开环反应,从而制得了TEMPO固载化微球TEMPO/CPGMA,考察了制备条件对固载化反应的影响,并采用多种方法对微球TEMPO/CPGMA进行了表征.将微球TEMPO/CPGMA与CuCl组成共催化体系,用于分子氧氧化苯甲醇,考察了反应条件对催化体系性能的影响.结果表明,以含环氧基团的聚合物微球CPGMA为载体,通过开环反应,可成功地实现TEMPO的固载化,开环反应属SN2亲核取代反应,适宜采用溶剂N,N′-二甲基甲酰胺和反应温度85℃.非均相催化剂TEMPO/CPGMA与助催化剂CuCl构成共催化体系,在室温、常压O2条件下可高效地将苯甲醇氧化为苯甲醛,产物选择性和产率分别为100%和90%.主催化剂TEMPO与助催化剂CuCl适宜的摩尔比为1:1.2;主催化剂适宜用量为0.90g.此外,TEMPO/CPGMA固体催化剂具有良好的循环使用性能.室温下以原位生成的醋酸咪唑鎓盐为催化剂和酰化剂用于醇、酚和胺的乙酰化反应(英文)
摘要：Acylimidazolium acetate was readily prepared in situ from the reaction of imidazole with acetic anhydride and subsequently acted as a catalyst and acylating agent for the efficient acetylation of alcohols, phenols, and amines at ambient temperature.Impact Factor of Chinese Journal of Catalysis increases from 1.171 to 1.304—congratulations and thanks to the authors of our most cited articles
摘要：<正>According to the Thomson Reuter report on 20 June 2013, the 2012 Impact Factor of Chinese Journal of Catalysis has improved from 1.171 to 1.304. Chinese Journal of Catalysis would like to express our congratulation and appreciation to all the authors who have been part of this success by publishing their good contribution in the Journal.