Loading...

List of Issues

    Chinese Journal of Catalysis
    2010, Vol. 31, No. 9
    Online: 30 September 2010

    Cover:

    A new series of methylsulfonyl-based sulfamide-amine alcohol ligands were synthesized by Wan and coworkers in their article on pages 1098–1102. These ligands can catalyze the enantioselective addition of terminal alkynes to aldehydes with satisfactory results. This helps to further understand the electronic and steric effects on the activity of the sul-famide-amine alcohol ligands.

    For Selected: Toggle Thumbnails
    Research Briefing
    Synthesis of the Novel Ligand Tris-(3,4-dimethoxylphenyl)phosphine and Its Catalytic Performance in 1-Dodecene Hydroformylation
    YUAN Maolin, FU Haiyan, LI Ruixiang, CHEN Hua*, LI Xianjun
    2010, 31 (9):  1093-1097.  DOI: 10.1016/S1872-2067(10)60105-2
    Abstract ( 3133 )   [Full Text(HTML)] () PDF (473KB) ( 1159 )  
    Tris-(3,4-dimethoxylphenyl)phosphine (TDMOPP) was synthesized and used as a ligand for the homogenous hydroformylation of 1-dodecene. The effects of the P/Rh molar ratio and reaction temperature on the activity and regioselectivity were investigated. The results showed that the activity of TDMOPP was about two times higher than that of the traditional triphenylphosphine at a low P/Rh and tempera-ture.
    Research papers
    Methylsulfonyl-Based Sulfamide-Amine Alcohol as a Ligand for Enantioselective Alkynylation of Aldehydes
    JIN Wei, HUANG Yongbo, WAN Boshun*
    2010, 31 (9):  1098-1102.  DOI: 10.1016/S1872-2067(10)60106-4
    Abstract ( 2342 )   [Full Text(HTML)] () PDF (419KB) ( 772 )  
    Chiral methylsulfonyl-based sulfamide-amine alcohol (SAA) ligands were synthesized from commercially available starting materials in two simple steps. Methylsulfonyl-based SAA ligands catalyzed the asymmetric alkynylation of various aldehydes using alkynylzinc to provide chiral propargyl alcohols with moderate to good enantioselectivity up to 83% ee.
    Chemoselective and Catalytic Trimethylsilylation of Alcohols and Phenols by 1,1,1,3,3,3-Hexamethyldisilazane and Catalytic Amounts of PhMe3N+Br3
    Arash GHORBANI-CHOGHAMARANI*, Nasrin CHERAGHI-FATHABAD
    2010, 31 (9):  1103-1106.  DOI: 10.1016/S1872-2067(10)60107-6
    Abstract ( 2311 )   [Full Text(HTML)] () PDF (279KB) ( 1274 )  
    An efficient procedure for the trimethylsilylation of alcohols and phenols is presented. The combination of 1,1,1,3,3,3-hexamethyldisilazane and a catalytic amount of phenyltrimethylammonium tribromide (PhMe3N+Br3) was found to be effective for the trimethylsilylation of alcohols and phenols. The protection reaction is very simple and homogenously performed in dichloromethane at room temperature and mild conditions.
    Selective Catalytic Reduction of NO in Excess Oxygen by Methane over Mn/ZSM-5 Catalysts
    CHEN Shuwei1, YAN Xiaoliang2, CHEN Jiaqi2, MA Jinghong2, LI Ruifeng1,2,*
    2010, 31 (9):  1107-1114.  DOI: 10.1016/S1872-2067(10)60108-8
    Abstract ( 2783 )   [Full Text(HTML)] () PDF (539KB) ( 986 )  
    The selective catalytic reduction of NO in excess O2 by CH4 was investigated over a series of ZSM-5-supported manganese catalysts (Mn/ZSM-5). The catalytic activity depended on preparation method and Mn loading. An ion exchange method resulted in a higher activity than an impregnation method. Catalytic activity increased with increasing Mn loading until a Mn loading of 2.06% that gave a maximum NO conversion of 57.3%. H2 temperature-programmed reduction results showed that the ion exchange method and low Mn loadings (≤ 2.06%) restricted the formation of non-stoichiometric MnOx (1.5 < x < 2) species that have higher oxidative activity, and thus suppressed the combustion of CH4 by O2, which increased the selectivity for NO reduction. In a SO2 containing stream, a substantial decrease in NO conversion was seen at ≤ 550 oC but not at ≥ 600 oC. SO2 temperature-programmed surface reaction and NO temperature-programmed desorption demonstrated that sulfur species were formed at temperature ≤ 550 oC, and these covered active sites and decreased the catalytic activity. The sulfur species desorbed at ≥ 600 oC, thus the addition of SO2 did not have a significant impact on the catalytic activity.
    Autothermal Reforming of CH4 and C3H8 to Syngas in a Fluidized-Bed Reactor
    GUO Jianzhong1,*, HOU Zhaoyin2, ZHENG Xiaoming2
    2010, 31 (9):  1115-1121.  DOI: 10.1016/S1872-2067(10)60109-X
    Abstract ( 2748 )   [Full Text(HTML)] () PDF (589KB) ( 860 )  
    The catalytic properties of Ni/SiO2 catalysts with different Ni particle size for the oxy-reforming of methane or methane-propane with CO2 and O2 (autothermal reforming) in a fluidized-bed reactor were investigated. The results show that Ni/SiO2 catalysts with smaller Ni particle size exhibit higher catalytic activity and improved resistance to carbon deposition. The conversion of methane and carbon dioxide was 75.5% and 72.6%, respectively, for the methane-propane autothermal reforming reaction. The propane dissociates and is oxidized more easily than methane. The CHx intermediate species from propane dissociation combines with the adsorbed hydrogen to produce methane, which results in a decrease in the apparent conversion of methane. Additionally, H2 and CO are generated by the reaction with adsorbed CO2, which promotes the conversion of the CO2.
    Preparation and Catalytic Properties of MgFe0.1Al1.9O4 in Oxidative Dehydrogenation of Ethylbenzene with CO2
    JIA Cuiying, CHEN Xin, JI Min*
    2010, 31 (9):  1122-1126.  DOI: 10.3724/SP.J.1088.2010.00112
    Abstract ( 2404 )   [Full Text(HTML)] () PDF (509KB) ( 707 )  
    The MgFe0.1Al1.9O4 catalyst with spinel structure was prepared by a sol-gel method using citric acid as the gelatinizer and was tested for dehydrogenation of ethylbenzene with CO2 at 600 ºC. The formation temperature of the spinel phase and the dispersion state of Fe species were characterized by X-ray diffraction, X-ray energy dispersive analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, N2 adsorption-desorption, and temperature-programmed reduction. The results indicate that the ternary-composite oxide catalyst of Mg-Fe-Al-O with a well-proportioned chemical composition, in which the Fe3+ species exist in spinel framework, can be obtained at the temperature higher than 650 ºC. With the increase in the preparation temperature, both the crystallinity and grain size of the catalyst increase and the reduction of Fe species decreases. MgFe0.1Al1.9O4 prepared by calcination at 700 ºC shows high activity and good stability for the ethylbenzene dehydrogenation with CO2 during 20 h time on stream.
    Density Functional Theory Study on the Relationship between Polymerization Activity and Substituent Electronic Effect of Polyolefin Catalysts
    LI Huayi1,*, ZHANG Liaoyun2, HU Youliang1
    2010, 31 (9):  1127-1131.  DOI: 10.3724/SP.J.1088.2010.00126
    Abstract ( 2543 )   [Full Text(HTML)] () PDF (402KB) ( 975 )  
    Eighteen polyolefin catalysts have been calculated using the density functional theory in the BP/DNP level. These compounds are classified into five groups with similar steric effect and different electronic effect. The Hirshfeld, Mulliken, and QEq charges and Fukui indexes of the central metals and HOMO and LUMO engeries of these compounds have been calculated. The QEq charge of the central metal and HOMO and LUMO energies have good correlation with the polymerization activity and can be used to predict polymerization activity of new designed catalysts. However, the Hirshfeld and Mulliken charges cannot correctly reflect the electronic effect change of the substituents. The Fukui index changes indecisively with substituent electronic effect and has inconspicuous correlation with the polymerization activities of these compounds.
    Mo and Cu Modified FeK/SiO2 Catalysts for Fischer-Tropsch Synthesis
    QIN Shaodong1,2, ZHANG Chenghua1,*, XU Jian1, WU Baoshan1, XIANG Hongwei1, LI Yongwang1
    2010, 31 (9):  1132-1138.  DOI: 10.3724/SP.J.1088.2010.00142
    Abstract ( 2741 )   [Full Text(HTML)] () PDF (704KB) ( 920 )  
    The effects of Mo and Cu promoters on the properties of FeK/SiO2 catalysts and their Fischer-Tropsch synthesis (FTS) performance were studied. The catalysts were characterized by N2 adsorption, H2 temperature-programmed reduction, X-ray diffraction, Mössbauer effect spectroscopy and X-ray photoelectron spectroscopy. The characterization results indicate that Mo addition inhibits the reduction and carburization of the catalysts, which is opposite to Cu promoter. When Mo and Cu are co-added, similar reduction and carburization behavior is observed as that of Cu promoter alone. FTS performance was tested at 280 oC, 1.5 MPa, 2 000 h-1, and syngas H2/CO = 2.0 in a fixed-bed reactor. The reaction results show that Mo addition decreases the FTS activity and improves the stability of heavy hydrocarbon (C5+) selec-tivity over the catalysts; Cu addition increases the activity but has no contribution to the stability of C5+ selectivity. For the co-promoted catalyst, stable selectivity to C5+ is obtained without sacrificing activity.
    Synthesis of Nickel Phosphate Nanotubes and Their Catalytic Performance for Cyclohexene Epoxidation
    WU Guang1,2, WANG Anjie1,*, LI Xiang1, WANG Yao1, HU Yongkang1
    2010, 31 (9):  1139-1144.  DOI: 10.3724/SP.J.1088.2010.00131
    Abstract ( 2424 )   [Full Text(HTML)] () PDF (1175KB) ( 953 )  
    Nickel phosphate nanotubes (NiPO-NTs) with a uniform pore size distribution were prepared by urea-assisted hydrothermal synthesis in the absence of any organic template. Calculations from N2 adsorption-desorption isotherms of NiPO-NTs revealed a narrow pore distribution around 2.7–4.2 nm and a surface area of 96.6 m2/g. NiPO-NTs was used to catalyze the epoxidation of cyclohexene using hydrogen peroxide as the oxidant. Infrared spectroscopy of adsorbed pyridine and NH3 temperature-programmed desorption characterization results showed that the weak Lewis acid was predominant on the surface of NiPO-NTs. CH3CN was found to be a suitable solvent for the epoxidation. The reaction conversion increased with increasing reaction temperature and H2O2/cyclohexene molar ratio, whereas the selectivity for epoxycyclohexane increased with decreasing temperature and increasing H2O2/cyclohexene molar ratio. High cyclohexene conversion (50.6%) and selectivity for epoxycyclohexane (72.1%) were obtained at 60 oC, 6 h, and H2O2/cyclohexene of 3.
    Relationship between Iron Phase and Activity of Iron-Based Fischer-Tropsch Synthesis Catalyst
    DING Mingyue1,2,*, YANG Yong2, XIANG Hongwei2, LI Yongwang2
    2010, 31 (9):  1145-1150.  DOI: 10.3724/SP.J.1088.2010.00139
    Abstract ( 2613 )   [Full Text(HTML)] () PDF (610KB) ( 1253 )  
    A typical Fe-based catalyst for Fischer-Tropsch synthesis (FTS) was prepared by a combination method of continuous co-precipitation and spray-drying technology. The study was undertaken to investigate the iron phase transformation under different pretreatment conditions and the influence of phase structure on FTS activity of the catalyst in a stirred tank slurry reactor. N2 adsorption-desorption, X-ray diffraction, and Mössbauer effect spectroscopy were used to characterize the catalyst. It was found that α-Fe2O3 in the fresh catalyst was reduced first to Fe3O4 and then converted to iron carbides (FexC) in the syngas atmosphere. Increasing the reduction space velocity promoted the reduction and carburization of the catalyst. Higher reduction pressure facilitated the reduction of α-Fe2O3 to Fe3O4 but suppressed the carburization of magnetite. During FTS the catalytic activity decreased gradually with increasing magnetite content and decreasing iron carbide content.
    Liquid-Phase Hydrogenation of Nitrobenzene over Ag-Ni Bimetallic Catalysts Prepared by Adsorption Phase Synthesis
    JIANG Xin, DONG Kezeng, WANG Haihua, WANG Ting*
    2010, 31 (9):  1151-1156.  DOI: 10.3724/SP.J.1088.2010.00137
    Abstract ( 2431 )   [Full Text(HTML)] () PDF (1738KB) ( 1029 )  
    Ag-Ni bimetallic nano-catalysts were prepared using silica and kaolin as the support by adsorption phase synthesis. The activity of these catalysts was evaluated by liquid-phase hydrogenation of nitrobenzene to aniline. By changing the Ni content and Ni/Ag molar ratio in the catalysts, the differences of morphology and activity between the catalysts on two supports were investigated. The results of tempera-ture-programmed reduction and transmission electron microscopy indicate that the bimetallic catalysts show higher activity when Ni/Ag molar ratio is 5. There is an optimal Ni content in the catalysts on both silica and kaolin, which is 0.04% for kaolin and 0.03% for silica. The catalyst supported by kaolin is more active and has higher aniline yield than the catalyst supported on silica.
    Production of 5-Hydroxymethylfurfural from Cellulose Catalyzed by Lewis Acid under Microwave Irradiation in Ionic Liquid
    WU Shuchang1,2, WANG Chunlei1, GAO Yongjun1,2, ZHANG Shaochun3, MA Ding1,*, ZHAO Zongbao1,4
    2010, 31 (9):  1157-1161.  DOI: 10.3724/SP.J.1088.2010.00149
    Abstract ( 2483 )   [Full Text(HTML)] () PDF (474KB) ( 992 )  
    Direct conversion of cellulose into 5-hydroxymethylfurfural (HMF) catalyzed by CrCl3•6H2O in ionic liquid 1-butyl-3-methylimidazolium chloride ([bmim]Cl) was described with the promotion of microwave. The effects of microwave irradiation setting, reaction temperature, reaction time, and catalyst amount on HMF yield were investigated. The results showed that cellulose was converted into HMF rapidly and efficiently in [bmim]Cl with the HMF yield of 55%.
    Influence of Step Temperature Elevating Decomposition on the Catalytic Activity of Non-supported Ni for Methane Decomposition
    ZHANG Wei1,2, GE Qingjie1,*, XU Hengyong1,*
    2010, 31 (9):  1162-1166.  DOI: 10.3724/SP.J.1088.2010.00148
    Abstract ( 2316 )   [Full Text(HTML)] () PDF (497KB) ( 702 )  
    The non-supported Ni catalyst was prepared by calcination of the nickel hydroxide precipitate, originated from precipitation of nickel acetate with aqueous solution of sodium carbonate, rinsed with ethanol. The influence of pretreatment conditions on Ni catalyst was investigated by means of X-ray diffraction, CH4 temperature-programmed surface reaction, and CH4 decomposition reactivity test. The results showed that lowering the reduction temperature could reduce Ni particle size and correspondingly improve the catalytic activity of Ni catalyst for CH4 decomposition. The result of the catalytic activity test showed that reaction history was an important factor influencing the catalytic activity of the Ni catalyst for CH4 decomposition at 500 oC. The formation of relatively stable Ni particles could be realized by carrying out CH4 decomposition stepwise at multiple reaction temperatures (multiple step temperature elevating decomposition), which could remarkably improve the catalytic activity and stability of the Ni catalyst for CH4 decomposition. The initial CH4 conversion reached 8.40% at 500 oC by using the multiple step temperature elevating decomposition method, and the CH4 conversion could further be increased to 11.20% within 120 min, whereas by the two step temperature elevating decomposition method, the maximum CH4 conversion at 500 oC was only 1.61%.
    Theoretical Study on the Mechanism of Ethanol Oxidation to Acetaldehyde Catalyzed by Liver Alcohol Dehydrogenase
    LI Xiaoying, WANG Changsheng*
    2010, 31 (9):  1167-1171.  DOI: 10.3724/SP.J.1088.2010.00208
    Abstract ( 2750 )   [Full Text(HTML)] () PDF (1164KB) ( 923 )  
    The mechanism of ethanol oxidation to aldehyde catalyzed by liver alcohol dehydrogenase in water and in protein environments was studied by the density function theory B3LYP method. The optimal structure of reactants, transition states, intermediates, and products were located at the B3LYP/6-31G** level of theory. The reaction barriers were then calculated and compared in water and in protein at the B3LYP/6-311++G(3df,2p) level of theory. The calculation results show that a high reaction barrier exists for the pathway where no catalyst is involved, suggesting that the oxidation cannot take place at room temperature without catalysts. A low reaction barrier exists when the liver alcohol dehydrogenase is involved, indicating that the liver alcohol dehydrogenase catalyzed reaction can take place at room temperature. The role of the liver alcohol dehydrogenase in the reaction was explored.
    Preparation of Metal Carbide Imbedded Ordered Mesoporous Carbon and Its Catalytic Properties for N2H4 Decomposition
    WANG Hui1,2, ZHANG Hui1,2, WANG Aiqin1, ZHANG Tao1,?
    2010, 31 (9):  1172-1176.  DOI: 10.3724/SP.J.1088.2010.00215
    Abstract ( 2864 )   [Full Text(HTML)] () PDF (1402KB) ( 1210 )  
    A metal carbide imbedded ordered mesoporous carbon (MC-OMC) material was synthesized by direct carbonization of a self-assembled composite that was made from F127 (EO106PO70EO106), resorcinol-formaldehyde, and (NH4)6Mo7O24•4H2O or (NH4)2WO4 in an acidic medium of aqueous ethanol solutions. The type and amount of the metal ions have a great influence on ordering degree of the resulting materials. Metal carbide particles with uniform size of 3–5 nm are highly dispersed on the pore wall of the carbon structure. The prepared MoC-OMC has excellent activity for direct N2H4 decomposition. The strong interaction between Mo7O246– and the resin plays an important role in the synthesis of this material.
    Biphasic Synergistic Effects of Mg-V-O Catalysts in Oxidative Dehydrogenation of Cyclohexane
    JIN Mei1, CHENG Zhenmin1,*, JIANG Xiaoxia1, GAO Yulan1,2, FANG Xiangchen2
    2010, 31 (9):  1177-1184.  DOI: 10.3724/SP.J.1088.2010.00204
    Abstract ( 2557 )   [Full Text(HTML)] () PDF (748KB) ( 834 )  
    The biphasic synergistic effect of a mechanically mixed Mg-V-O catalyst system, which included MgO-Mg3(VO4)2, Mg3(VO4)2- Mg2V2O7, and V2O5-MgV2O6 catalysts, in the oxidative dehydrogenation of cyclohexane was studied. Characterization results and catalytic performance measurements reveal that the biphasic synergistic effect derives from three mechanisms: the formation of coherent interface of the two phases, the remote control mechanism originated from the spillover of mobile surface oxygen, and the formation of a surface con-tamination layer of one phase on the surface of the catalyst. The biphasic synergistic effect on the conversion, yield, and selectivity was ob-served in Mg3(VO4)2 mixing with a suitable amount of MgO and Mg2V2O7. Among the catalyst system, the 80%Mg3(VO4)2- 20%Mg2V2O7 catalyst exhibits better catalytic performance and shows cyclohexene selectivity of 44.9% with cyclohexane conversion of 15.5%.
    Promoting Effect of Cu on MnCeOx-Catalyzed Phenol Oxidation in Aqueous Phase
    TONG Changshui1,2, TONG Xiaoxia1, JIN Menggui1,*, YE Nianjun3
    2010, 31 (9):  1185-1188.  DOI: 10.3724/SP.J.1088.2010.00214
    Abstract ( 2229 )   [Full Text(HTML)] () PDF (475KB) ( 797 )  
    Cu-modified MnCeOx catalysts were prepared and applied to the oxidative degradation of aqueous phenol solutions. The modification by Cu increased phenol oxidation and chemical oxygen demand removal of aqueous phenol solutions. The promotion effects of Cu were analyzed by X-ray diffraction and temperature-programmed reduction. It was found that CuMn2O4 formed with the addition of Cu, which was favorable for the increase of catalytic activity.