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Chinese Journal of Catalysis
2013, Vol. 34, No. 4
Online: 23 April 2013


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In their article on pages 684–694, Sun and coworkers report that a Ru-Mn catalyst with an optimum Mn content of 5.4% gave a cyclohexene yield of 61.3%. They confirmed that the chemisorbed [Zn(OH)₂]₃(ZnSO₄)(H₂O)₃ salt, which was formed by the reaction of Mn₃O₄ with ZnSO4 in the slurry, improved the cyclohexene selectivity over the Ru catalyst.

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Table of Contents for Vol. 34 No. 4 2013, 34 (4):  0-0.  Abstract ( 323 )   PDF (1731KB) ( 370 )

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Recent progress in the preparation and application of semiconductor/graphene composite photocatalysts CHEN Jianwei, SHI Jianwen, WANG Xu, CUI Haojie, FU Minglai 2013, 34 (4):  621-640.  DOI: 10.1016/S1872-2067(12)60530-0 Abstract ( 1263 )   [Full Text(HTML)] () PDF (2256KB) ( 1668 )   Graphene is a new material with a single-layer laminar structure of carbon atoms that possesses favorable physical and chemical properties such as high electrical conductivity, high chemical stability, and large specific surface area. Combining graphene with semiconductors to form composite photocatalysts can extend its light absorption edge, improve the migration rate of charge carriers, and enhance the adsorption capacity of contaminants. The unique two-dimensional planar structure of graphene endows composite photocatalysts with many excellent properties. Herein, the properties of graphene, semiconductor, and composite photocatalysts are first introduced. The various preparation methods of semiconductor/graphene composite photocatalysts are then presented, and the mechanisms behind enhanced photocatalysis are summarized. Four typical applications of composite photocatalysts: elimination of organic pollutants, hydrogen production, organic fuel production via CO2 reduction, and photocatalytic sterilization, are described in detail. Finally, the direction of future research on semiconductor/graphene composite photocatalysts is explored.

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Recent progress of catalytic pyrolysis of biomass by HZSM-5 TAN Shun, ZHANG Zhijun, SUN Jianping, WANG Qingwen 2013, 34 (4):  641-650.  DOI: 10.1016/S1872-2067(12)60531-2 Abstract ( 885 )   [Full Text(HTML)] () PDF (437KB) ( 1756 )   Biomass can be converted into a variety of fuels and chemicals using different technologies. One such process is fast pyrolysis, which is convenient for the conversion of biomass primarily into liquid products known as bio-oils. These bio-oils, however, must be upgraded if they are to be used as a replacement for diesel and gasoline fuels. At present, when improving the quality of bio-oils, catalytic vapor cracking is generally considered superior to other catalytic upgrading technologies, such as hydrotreating and esterification. This review summarizes the current status of research concerning both the catalytic pyrolysis of biomass and the catalytic cracking of bio-oil using the zeolite HZSM-5, focusing on the specific catalysts employed, as well as the upgrading methods and reaction mechanisms.

Communications

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Hydrogenation and cleavage of the C-O bonds in the lignin model compound phenethyl phenyl ether over a nickel-based catalyst SONG Qi, CAI Jiaying, ZHANG Junjie, YU Weiqiang, WANG Feng, XU Jie 2013, 34 (4):  651-658.  DOI: 10.1016/S1872-2067(12)60535-X Abstract ( 747 )   [Full Text(HTML)] () PDF (615KB) ( 1057 )   Phenethyl phenyl ether (PPE) was selected as a typical lignin model compound and hydrogenated and cleaved over two readily accessible nickel-based catalysts, which could be easily separated from the product mixture. The results revealed that the reduction of the nickel catalyst with gaseous hydrogen produced a species capable of achieving higher activity towards C-O-C bond cleavage compared to the Ru/C and Pd/C catalysts. The selectivity of the C-O-C bond cleavage over the Ni/C catalyst was 85%, and higher than the corresponding values in the Ru/C (40%) and Pd/C (69%) systems. Using the carbothermal reduction method for the production of the Ni/C-C catalyst, the conversion and selectivity levels reached 99%, with 40% of the benzene rings in PPE being reserved. In comparison, no benzene ring containing products wer observed over the noble metal catalysts. This difference was attributed to the interaction between the carbon support and the nickel nanoparticles.

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Sulfided Mo/Al2O3 hydrodesulfurization catalyst prepared by ethanol-assisted chemical deposition method SHI Gang, HAN Wei, YUAN Pei, FAN Yu, BAO Xiaojun 2013, 34 (4):  659-666.  DOI: 10.1016/S1872-2067(11)60516-0 Abstract ( 538 )   [Full Text(HTML)] () PDF (1313KB) ( 773 )   In this communication, we report a novel strategy to prepare a MoS2/Al2O3 hydrodesulfurization (HDS) catalyst by thermally treating a MoS3/Al2O3 precursor in H2 atmosphere. In our approach, the active phase precursor MoS3 was first prepared using thioacetamide and sodium molybdate as sources of S and Mo, respectively, and ethanol as a dispersant. The precursor was deposited onto the surface of a γ-Al2O3 support and heat-treated to form the catalyst. The catalyst was characterized by N2 adsorption-desorption, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. The HDS activity of the catalyst was assessed using dibenzothiophene as a model reactant. The catalyst possessed larger specific surface area and pore volume, higher dispersion and degree of sulfidation of Mo species, and shorter and more suitable stacking of MoS2 slabs, resulting in superior catalytic activity compared with a catalyst with the same metal content prepared by the conventional impregnation method. Ethanol could disperse the precursor MoS3 particles via “S…H-O” H-bonding to lessen their aggregation.

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A novel diesel oxidation catalyst with low SO2 oxidation activity and capable of meeting Euro V emission standards CHEN Yongdong, WANG Lei, GUAN Xiaoxu, TANG Shuihua, GONG Maochu, CHEN Yaoqiang 2013, 34 (4):  667-673.  DOI: 10.1016/S1872-2067(12)60545-2 Abstract ( 571 )   [Full Text(HTML)] () PDF (652KB) ( 738 )   A diesel oxidation catalyst was prepared from several high performance materials: the new rare earth oxygen storage compound Ce0.75Zr0.25O2-Al2O3, the composite oxide Ti0.9Zr0.1O2 and chromium-modified β molecular sieve. These component materials were characterized and used to prepare a Pt-based catalyst designed to reduce diesel engine exhaust emissions. The results of low temperature N2 adsorption-desorption and oxygen storage capacity tests demonstrated that Ce0.75Zr0.25O2-Al2O3 exhibits a large specific surface area and excellent oxygen storage capacity, and that Ti0.9Zr0.1O2 exhibits superior textural properties. Evaluations of catalytic activity showed that the catalyst prepared from these materials has reduced capacity for the oxidation of SO2 but high catalytic activity towards the oxidation of hydrocarbons (HC) and CO, and is also able to convert the exhaust soluble organic fraction at temperatures as low as 140℃. Tests using a domestic YC4F-type diesel engine found that exhaust treated by the catalyst prepared in this research is capable of meeting the HC and CO emission requirements of the Euro V standard.

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Thermoregulated poly(ethylene glycol) biphasic system with Pd nanoparticle catalysts for selective hydrogenation of cinnamaldehyde NIU Mingming, WANG Yanhua, LI Wenjiang, JIANG Jingyang, JIN Zilin 2013, 34 (4):  674-678.  DOI: 10.1016/S1872-2067(12)60552-X Abstract ( 649 )   [Full Text(HTML)] () PDF (635KB) ( 739 )   Poly(ethylene glycol) (PEG)-stabilized Pd nanoparticles were prepared by simple hydrogen reduction of PdNa2Cl4?xH2O in the presence of PEG4000 (PEG with an average molecular mass of 4000 g/mol). These were shown to be efficient and recyclable catalysts for the selective hydrogenation of cinnamaldehyde in a thermoregulated PEG biphasic system, which allows for an efficient homogeneous catalytic reaction, easy biphasic separation and catalyst reuse. Under optimized reaction conditions, the conversion of cinnamaldehyde and the selectivity of hydrocinnamaldehyde (HCAL) were 99% and 98%, respectively. The PEG4000-stabilized Pd nanoparticle catalyst could be easily separated from the product by phase separation and reused eight times without evident loss of activity and selectivity.

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Rh(III)-catalyzed oxidative synthesis of pyrazoles from azomethines and acrylamides ZHEN Wencui, DU Zhengyin, LI Xingwei 2013, 34 (4):  679-683.  DOI: 10.1016/S1872-2067(12)60584-1 Abstract ( 619 )   [Full Text(HTML)] () PDF (432KB) ( 706 )   A cationic Rh(III) complex has been developed to catalyze the oxidative coupling of azomethine imines to acrylamides, to give trisubstituted pyrazoles in moderate yield. In this process, the olefinic C-H bond of the acrylamide undergoes C-H activation, and the reaction subsequently proceeds via a different selectivity to that reported for the coupling of acrylate esters.

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Selective hydrogenation of benzene to cyclohexene over nanocomposite Ru-Mn/ZrO2 catalysts SUN Haijie, JIANG Houbing, LI Shuaihui, WANG Hongxia, PAN Yajie, DONG Yingying, LIU Shouchang, LIU Zhongyi 2013, 34 (4):  684-694.  DOI: 10.1016/S1872-2067(11)60489-0 Abstract ( 824 )   [Full Text(HTML)] () PDF (1045KB) ( 1015 )   A series of Ru-Mn catalysts with different Mn contents were prepared by coprecipitation, and their catalytic performance, using nanoscale ZrO2 as a dispersant, for the selective hydrogenation of benzene to cyclohexene was investigated. The catalysts were characterized using X-ray diffraction, transmission electron microscopy, N2 physisorption, X-ray fluorescence, atomic absorption spectroscopy, and Auger electron spectroscopy. The results confirmed that the Mn existed as Mn3O4 on the Ru surface. The Mn3O4 reacted with ZnSO4 to form an insoluble [Zn(OH)2]3(ZnSO4)(H2O)3 salt, which was readily chemisorbed on the Ru surface. This chemisorbed salt played a key role in improving the cyclohexene selectivity over the Ru catalyst. The cyclohexene yield of 61.3% was obtained over the Ru-Mn catalyst with the optimum Mn content of 5.4%. This catalyst had good stability and excellent reusability.

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A succinimide-N-sulfonic acid catalyst for acetylation reactions in absence of a solvent Farhad SHIRINI, Nader Ghaffari KHALIGH 2013, 34 (4):  695-703.  DOI: 10.1016/S1872-2067(11)60499-3 Abstract ( 694 )   [Full Text(HTML)] () PDF (382KB) ( 867 )   A small amount of succinimide-N-sulfonic acid efficiently catalyzed the acetylation of a variety alcohols, phenols, thiols, amines and aldehydes with acetic anhydride at room temperature under solvent free conditions. This catalyst has the advantages of excellent yields and short reaction times and the reaction can be carried out on a large scale, which makes it potentially useful for industrial applications.

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Combustion-derived CuO nanoparticles: An effective and environmentally benign catalyst in the synthesis of aromatic nitriles from aromatic aldehydes Belladamadu Siddappa ANANDAKUMAR, Muthukur Bhojegowd Madhusudana REDDY, Chikka Nagaiah THARAMANI, Mohamed Afzal PASHA, Gujjarahalli Thimmanna CHANDRAPPA 2013, 34 (4):  704-710.  DOI: 10.1016/S1872-2067(11)60503-2 Abstract ( 796 )   [Full Text(HTML)] () PDF (851KB) ( 1199 )   CuO nanoparticles were synthesized using an energy-efficient and rapid solution combustion technique with malic acid employed as a fuel. The combustion-derived CuO nanoparticles were used as catalysts in a one-pot synthesis of aromatic nitriles from aromatic aldehydes and hydroxylamine hydrochloride. The catalyst was characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, transmission electron microscopy, and Brunauer-Emmett-Teller surface area analysis. The catalytic activity of the CuO nanoparticles in the synthesis of aromatic nitriles from aromatic aldehydes was evaluated. The present protocol offers the advantages of a clean reaction, simple methodology, short reaction duration (1-2 min), and high yield (85%-98%). The catalytic activity of the CuO nanoparticles was found to be higher than that of bulk CuO powder under the same conditions. The catalyst can also be recovered and reused up to four times with no significant loss of catalytic activity. The present approach is inexpensive and is a convenient technique suitable for industrial production of CuO nanoparticles and nitriles.

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Preparation of CuS-graphene oxide/TiO2 composites designed for high photonic effect and photocatalytic activity under visible light PARK ChongYeon, GHOSH Trisha, MENG ZeDa, KEFAYAT Ullah, VIKRAM Nikam, OH WonChun 2013, 34 (4):  711-717.  DOI: 10.1016/S1872-2067(11)60502-0 Abstract ( 928 )   [Full Text(HTML)] () PDF (797KB) ( 1120 )   CuS-graphene oxide/TiO2 composites were prepared using a sol-gel method to improve the photocatalytic performance of the photocatalyst. The composites were characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, and transmission electron microscopy. The photocatalytic activities were examined by the degradation of methylene blue (MB) under visible-light irradiation. The photodegradation of MB under visible-light irradiation reached 90.1% after 120 min. The kinetics of MB degradation was plotted alongside the values calculated from the Langmuir-Hinshelwood equation. The CuS-graphene oxide/TiO2 sample prepared using 0.2 mol of TiO2 showed the best photocatalytic activity. This was attributed to a cooperative reaction as a result of increased photoabsorption by graphene oxide and an increased photocatalytic effect by CuS.

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Silica-functionalized N-propylpiperazine for immobilization of palladium nanoparticles as efficient heterogeneous catalyst for cyanation reactions Khodabakhsh NIKNAM, Abdollah DERIS, Farhad PANAHI 2013, 34 (4):  718-722.  DOI: 10.1016/S1872-2067(12)60532-4 Abstract ( 763 )   [Full Text(HTML)] () PDF (503KB) ( 642 )   An efficient heterogeneous Pd catalytic system has been developed, based on immobilization of Pd nanoparticles (PNPs) on a silica-bonded N-propylpiperazine (SBNPP) substrate. The SBNPP substrate effectively stabilizes the PNPs and improves their stability against aggregation. The catalytic activity of this catalyst was investigated in the cyanation of aryl halides with K4[Fe(CN)6] as the cyanide source. The catalyst could be recycled several times without appreciable loss of catalytic activity.

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Catalytic performance and stability of C-C bond hydrolase BphD immobilized onto single-wall carbon nanotubes SHEN E, QU Yuanyuan, ZHOU Hao, KONG Chunlei, MA Qiao, ZHANG Xuwang, ZHOU Jiti 2013, 34 (4):  723-733.  DOI: 10.1016/S1872-2067(12)60564-6 Abstract ( 610 )   [Full Text(HTML)] () PDF (1267KB) ( 706 )   Single-wall carbon nanotubes (SWCNTs) possess unique mechanical properties and extraordinary thermal conductivity, and were used as the matrix for immobilized biocatalysts. The C-C bond hydrolase BphD was immobilized on SWCNTs by physical adsorption and covalent bonding. The relative activity, stability, and reusability of the immobilized enzyme were investigated. BphD immobilized by physical adsorption retained 52.5% of the activity of free BphD, and BphD thermal stability and denaturant resistance were also improved. Covalently bound BphD exhibited the activity nearly the same as that of free BphD (99.7% of initial activity), but its stability showed no significant improvement over that of free BphD.

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Behavior of gold nanoparticles in a titania aerogel matrix: Photocatalytic activity assessment and structure investigations Zsolt PAP, Andreea RADU, Izabella Jolan HIDI, Georgian MELINTE, Lucian DIAMANDESCU, Traian POPESCU, Lucian BAIA, Virginia DANCIU, Monica BAIA 2013, 34 (4):  734-740.  DOI: 10.1016/S1872-2067(11)60500-7 Abstract ( 706 )   [Full Text(HTML)] () PDF (749KB) ( 766 )   TiO2-Au aerogels containing different amounts of gold nanoparticles of different sizes (5 and 16 nm) were successfully synthesized using a sol-gel procedure, and were tested for salicylic acid photodegradation under UV irradiation. The structure and morphology of the obtained materials were investigated using X-ray diffraction, transmission electron microscopy, and N2 adsorption-desorption measurements. UV-Vis spectroscopy was used to study the optical properties. The effects of the gold nanoparticles on the TiO2 crystallization process were twofold, as follows: (i) the number of crystallized zones was strongly related to the concentration of the gold nanoparticles, and (ii) the smaller gold particles increased the time taken for the crystallization of the samples. It was found that the noble metal-doped samples exhibited higher degradation rates compared with bare titania. It was found that the most active photocatalyst in each studied system was the sample with the highest concentration of gold nanoparticles. Additionally, the highest degradation rate value was obtained with the smallest Au nanoparticles (46.4 × 10-3 μmol/(L·s).

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Immobilization of glucose oxidase in liposome-templated biomimetic silica particles ZHU Yanan, JIANG Yanjun, GAO Jing, ZHOU Liya, HE Ying, JIA Fei 2013, 34 (4):  741-750.  DOI: 10.1016/S1872-2067(11)60519-6 Abstract ( 811 )   [Full Text(HTML)] () PDF (711KB) ( 771 )   Glucose oxidase (GOx) was immobilized in biomimetic silica particles by coupling liposome vesicles with a biomimetic silicification process simulating a cell microenvironment. SEM images showed that the immobilized GOx particles were spherical, and their diameter was approximately 200 nm. The recovery of GOx reached 71.8% under the optimized reaction conditions. The immobilized GOx showed improved thermal and pH stability, and its tolerance to denaturants and reusability were also greatly improved. This was attributed to the space limitations and stable environment in the support.

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Ultrasonic-assisted fabrication and catalytic activity of CeZrAl oxide-supported Pd for the purification of gasohol exhaust LIU Jianying, ZHAO Ming, XU Chenghua, LIU Shengyu, ZHANG Xueqiao, CHEN Yaoqiang 2013, 34 (4):  751-757.  DOI: 10.1016/S1872-2067(11)60488-9 Abstract ( 748 )   [Full Text(HTML)] () PDF (532KB) ( 647 )   CeZrAl oxides (CZA) using as the support of Pd catalyst for purification of gasohol exhausts are synthesized by co-precipitation assisted by ultrasonic vibration. CZA are characterized by surface analysis, X-ray diffraction, temperature-programmed reduction by hydrogen, oxygen storage capacity (OSC), and X-ray photoelectron spectroscopy. The results show that ultrasonic vibration promotes the formation of smaller, more uniform pores in CZA, which is beneficial to the dispersion of Pd species. Ultrasonic vibration can also improve the OSC and uniformity of the composition of CZA on its surface and in bulk. Catalytic tests demonstrate that ultrasonic treatment of CZA widens the window of the full use of oxygen from 0-0.64% to 0-1.16% of Pd-CZA catalysts in the purification of gasohol exhaust, and decreases the light-off temperature of ethanol, propane, and carbon monoxide by 30, 28, and 24℃, respectively. Moreover, the interaction between Pd species and CZA can enhance the reaction of NO with propane and ethanol.

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Synthesis of polyhydroquinoline derivatives via a four-component Hantzsch condensation catalyzed by tin dioxide nanoparticles Seyed Mohammad VAHDAT, Fereshteh CHEKIN, Mehdi HATAMI, Maryam KHAVARPOUR, Saeed BAGHERY, Ziba ROSHAN-KOUHI 2013, 34 (4):  758-763.  DOI: 10.1016/S1872-2067(11)60518-4 Abstract ( 569 )   [Full Text(HTML)] () PDF (564KB) ( 920 )   Tin dioxide (SnO2) nanoparticles efficiently catalyzed unsymmetrical four-component Hantzsch condensations of various aldehydes, dimedone, ethyl acetoacetate, and ammonium acetate to form polyhydroquinoline derivatives in excellent yields. This novel method offers several advantages over the traditional method of synthesizing these compounds, including safety, mild conditions, short reaction times, high yields, and an easy workup.

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Stabilities of zeolite-supported Ni catalysts for dry reforming of methane Anis H. FAKEEHA, Wasim U. KHAN, Ahmed S. AL-FATESH, Ahmed E. ABASAEED 2013, 34 (4):  764-768.  DOI: 10.1016/S1872-2067(12)60554-3 Abstract ( 788 )   [Full Text(HTML)] () PDF (316KB) ( 1171 )   Ni/γ-Al2O3, Ni/Y-zeolite, and Ni/H-ZSM-5 catalysts were prepared using the incipient wetness impregnation method. Their catalytic performance in dry reforming of methane was studied. The fresh and used catalysts and deposited carbon were characterized using H2 temperature-programmed reduction, temperature-programmed oxidation, N2 adsorption-desorption, X-ray diffraction, and thermogravimetric analysis. The H-ZSM-5-supported Ni catalyst proved to be more stable than the other two catalysts, as it had the lowest carbon deposition.

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Effect of imidazolium ionic liquids on the hydrolytic activity of lipase LI Na, DU Weiyan, HUANG Zhuonan, ZHAO Wei, WANG Shoujiang 2013, 34 (4):  769-780.  DOI: 10.1016/S1872-2067(11)60521-4 Abstract ( 910 )   [Full Text(HTML)] () PDF (690KB) ( 701 )   The effect of 1-alkyl-3-methylimidazolium ionic liquids (ILs) on the hydrolysis activity of Candida rugosa lipase (CRL) toward triacylglycerol was investigated. The critical micelle concentrations (CMC) of ILs with Br-, Cl-, and [BF4]- anions and the solubility of ILs with [PF6]- anions were determined in phosphate buffer. Results suggested that the content of the ILs, not kosmotropicity, highly influenced the effects of anions and cations of ILs on CRL activity. As the length of alkyl chain of the cation [CnMIM]+ increased, lower IL content was required to achieve high enzyme activity. Once the concentrations of the ILs with Br-, Cl-, and [BF4]- anions exceeded the CMC value, enzyme activity was suppressed. The positive promotion effect of anions on enzyme activity was in the order of Br- > Cl- > [BF4]- > [PF6]-. The effect of ionic liquid on enzyme activity was highly dependent on the pH and temperature of the system, with the optimum pH being 7.000. Under optimal conditions of pH 7.000, 30℃, and 47.6 mmol/L of [C8MIM]Br, the highest relative activity of CRL (1734%) was achieved, with a specific activity of 54.4 U/mg protein.

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In situ FTIR study of low-pressure hydroformylation of 1-hexene catalyzed by ultrafine cobalt nanoparticles WANG Hang, CAI Zhipeng, ZHONG Mengqi, YAO Siyu, KOU Yuan 2013, 34 (4):  781-788.  DOI: 10.1016/S1872-2067(11)60504-4 Abstract ( 589 )   [Full Text(HTML)] () PDF (540KB) ( 666 )   The hydroformylation of 1-hexene in syngas (CO:H2 = 1) under 2-3 MPa at 100℃ was catalyzed using 2.8 nm ultrafine cobalt nanoparticles and investigated by in situ Fourier transform infrared spectroscopy (FTIR). A group of bands observed in the in situ FTIR spectra at 2071, 2041, and 2022 cm-1 are assigned to terminal CO adsorptions distributed over different Co sites. A band at 2054 cm-1 is attributed to the intermediate, RCH2CH2COCo, which has been observed for the first time. Through this intermediate, the catalytic reaction proceeds via the elimination of RCH2CH2COCo to leave a single H atom on the surface of each 2.8-nm Co nanoparticle.

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Effect of metals on titanium silicalite TS-1 for butadiene epoxidation WU Mei, CHOU Lingjun, SONG Huanling 2013, 34 (4):  789-797.  DOI: 10.1016/S1872-2067(11)60498-1 Abstract ( 751 )   [Full Text(HTML)] () PDF (585KB) ( 883 )   The titanium silicalite-1 (TS-1) modified by various metals (M-TS-1; M = V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, La, 1% metals loading) catalysts were employed to catalyze butadiene epoxidation. The metals influenced the TS-1 activity in various ways. V, Cr, and Mn caused H2O2 decomposition. Although the H2O2 conversion was high, its utilization was relatively low. The introduction of Fe, Co, Ni, and La into TS-1 promoted the vinyloxirane (VO) yield and H2O2 utilization to some extent. Cu and Zn modification inhibited the H2O2 conversion to VO, resulting in both low H2O2 utilization and conversion. We studied the influence of Cd on TS-1 and found that H2O2 was almost totally converted to VO over the Cd-TS-1 catalyst, and the turnover number of VO reached 1197. Powder X-ray diffraction, N2 adsorption and desorption, X-ray photoelectron spectroscopy, and Fourier transformed infrared spectra were employed to characterize the specific metal role at the Ti site in the M-TS-1 catalysts. The TS-1 remained as MFI structure with doped metals. The added metals effectively changed the electron environment of the Ti active site. However, no universal trend in behavior was observed for these metals.

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Synthesis of SAPO-35 molecular sieve and its catalytic properties in the methanol-to-olefins reaction LI Bing, TIAN Peng, LI Jinzhe, CHEN Jingrun, YUAN Yangyang, SU Xiong, FAN Dong, WEI Yingxu, QI Yue, LIU Zhongmin 2013, 34 (4):  798-807.  DOI: 10.1016/S1872-2067(12)60557-9 Abstract ( 672 )   [Full Text(HTML)] () PDF (855KB) ( 880 )   SAPO-35 molecular sieve samples with different Si contents were hydrothermally synthesized using hexamethyleneimine as the template and characterized by XRD, XRF, SEM, MAS NMR, XPS and N2 physisorption. Three SAPO-35 samples were tested as methanol-to-olefins catalysts. After the reaction, the evolution of coke species was investigated over SAPO-35 and SAPO-34 catalysts with similar Si concentrations. A correlation between the cage size of the molecular sieves and the coke species was obtained.

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Controllable synthesis and photocatalytic properties of hierarchical flower-like TiO2 nanostructure DU Lixia, WU Zhijiao, WU Qian, JIANG Chao, PIAO Lingyu 2013, 34 (4):  808-814.  DOI: 10.3724/SP.J.1088.2013.21281 Abstract ( 913 )   [Full Text(HTML)] () PDF (2127KB) ( 1106 )   Hierarchical flower-like TiO2 nanostructure has been successfully synthesized via a modified hydrothermal technique. The effects of the concentrations of H2O2, HNO3, and NaOH, as well as the reaction temperature and time on the morphology of TiO2 have been studied. The morphology, microstructure, and specific surface area of the flower-like TiO2 structure were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and surface area analysis. The photocatalytic activity of the TiO2 obtained under different conditions for degradation of methylene blue dye was investigated by ultraviolet light irradiation. The hierarchical flower-like anatase TiO2 nanostructure has a high specific surface area, and exhibits excellent activity in the photocatalytic degradation of methylene blue.