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    Chinese Journal of Catalysis
    2011, Vol. 32, No. 9
    Online: 09 September 2011

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    Prof. Gao and coworkers in their article on pages 1446–1451 report a quick process to produce phenol from benzene promoted by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and using oxygen as the oxidant. They suggest a mechanism of a linked catalysis effect on benzene hydroxylation involving TEMPO. Hydroxyl radicals generated from O2/V-based catalyst/ascorbic acid first attack benzene to form hydroxycy-clohexadienyl radicals. Then phenol is produced by benzene hydrogen transfer to the hydroxyl oxygen with the abstraction of the hydroxyl hy-drogen accelerated by TEMPO.

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    Table of Contents
    Table of Contents for Vol.32 No. 9
    2011, 32 (9):  0-0. 
    Abstract ( 1397 )   PDF (3436KB) ( 1029 )  
    Summary
    Reactivity of Iminopyrrole Ligands with Transition Metals and Catalytic Activity of Complexes for Olefin Polymerization
    SU Bi-Yun, TUO Hong-Bing, ZHANG Qun-Zheng
    2011, 32 (9):  1439-1445.  DOI: 10.3724/SP.J.1088.2011.10423
    Abstract ( 2948 )   [Full Text(HTML)] () PDF (776KB) ( 1213 )  
    Nitrogen-based variations of the bis(imino)pyridine incorporated late transition metal catalysts for olefin polymerization have recently attracted attention owing to their flexible complexation to transition metals. Because steric and electronic demands can be readily introduced to the iminopyrrole unit, a wide variety of ligands and corresponding complexes have been designed and synthesized. In this contribution, we briefly review reactivity and structural features of iminopyrrolyl ligands with early transition metals Ti and Zr, late transition metals Fe, Co, Ni, and Pd, rare earth metals Y, Ir, Lu, and Nd as well as other metals such as Cu, U, and Cr and their catalytic activity for olefin polymerization.
    Research Briefing
    2,2,6,6-Tetramethylpiperidine-1-Oxyl-Promoted Hydroxylation of Benzene to Phenol over a Vanadium-Based Catalyst Using Molecular Oxygen
    CHEN Jia-Qi, GAO Shuang, LI Jun, Lü Ying
    2011, 32 (9):  1446-1451.  DOI: 10.1016/S1872-2067(10)60254-9
    Abstract ( 3270 )   [Full Text(HTML)] () PDF (769KB) ( 1001 )  
    Rapid benzene hydroxylation was achieved using a reaction system that consisted of a vanadium-based catalyst, ascorbic acid, and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) with molecular oxygen as the oxidant. The hydroxyl radicals that form by a Fenton-type process attack the benzene ring to produce a hydroxycyclohexadienyl radical. The hydroxyl hydrogen is then abstracted quickly in the presence of TEMPO and phenol forms by the transfer of a hydrogen atom from the benzene ring to oxygen. Over the [(CH3)4N]4-PMo11VO40 catalyst the phenol yield reached 8.3% with a selectivity of 95% in 1 h while trace amounts of phenol were obtained in the normal system without TEMPO.
    Research papers
    Preparation of Cu/ZnO/Al2O3 Catalyst for CO2 Hydrogenation to Methanol by CO2 Assisted Aging
    WANG Dan-Jun, TAO Fu-Rong, ZHAO Hua-Hua, SONG Huan-Ling, CHOU Ling-Jun
    2011, 32 (9):  1452-1456.  DOI: 10.1016/S1872-2067(10)60256-2
    Abstract ( 3305 )   [Full Text(HTML)] () PDF (725KB) ( 1219 )  
    A Cu/ZnO/Al2O3 catalyst prepared by adding CO2 during the aging step was used for methanol synthesis from CO2 and H2. The catalysts were characterized by N2 adsorption-desorption, X-ray diffraction, field emission scanning electron microscope, temperature-programmed decomposition, and temperature-programmed reduction. The precursor from the modified method with added CO2 had malachite and hydrotalcite-like phases and was more stable than that of the sample without added CO2. After calcination, the modified catalyst had a higher surface area, larger pore volume, and smaller particle size. The modified catalyst gave a higher activity for methanol synthesis from CO2 hydrogenation in the reaction temperature range of 200–260 ºC.
    Rare Earth Oxide-Treated Fullerene and Titania Composites with Enhanced Photocatalytic Activity for the Degradation of Methylene Blue
    MENG Zada, ZHU Lei, CHOI Jong-geun, PARK Chong-yeon, OH Won-chun
    2011, 32 (9):  1457-1464.  DOI: 10.1016/S1872-2067(10)60258-6
    Abstract ( 2980 )   [Full Text(HTML)] () PDF (848KB) ( 1260 )  
    Rare earth oxide-treated fullerene and titania composites (Y-fullerene/TiO2) were prepared by the sol-gel method. The products had interesting surface compositions. X-ray diffraction patterns of the composites showed that the Y-fullerene/TiO2 composites contained a single and clear anatase phase. The surface properties were observed by scanning electron microscopy, which gave a characterization of the texture on the Y-fullerene/TiO2 composites and showed a homogenous distribution of titanium particles. The energy-dispersive X-ray spectra showed the presence of C and Ti with strong Y peaks. The composite obtained was also characterized with transmission electron microscopy and UV-Vis spectroscopy. The photocatalytic results showed that the Y-fullerene/TiO2 composites had excellent activity for the degradation of methylene blue under visible light irradiation. This was attributed to both the effects on the photocatalysis of the supported TiO2 by charge transfer by the fullerene, and the introduction of yttrium to enhance photo-generated electron transfer.
    Synthesis, Characterization, and Catalytic Activity of Nanocrystalline La1-xEuxFeO3 during the Combustion of Toluene
    Seyed Ali HOSSEINI, Mohammad Taghi SADEGHI-SORKHANI, Leila KAFI-AHMADI, Abdolali ALEMI, Aligholi NIAEI, Dariush SALARI
    2011, 32 (9):  1465-1468.  DOI: 10.1016/S1872-2067(10)60257-4
    Abstract ( 2790 )   [Full Text(HTML)] () PDF (807KB) ( 1056 )  
    Nanostructured LaFeO3 and substituted La1-xEuxFeO3 (x = 0.1, 0.15, and 0.2) perovskites were synthesized by sol-gel auto-combustion and their activities during the combustion of toluene were evaluated. The structure and physico-chemical properties of the perovskites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and BET surface area analyses. The compounds were crystallized as a perovskite phase with an orthorhombic structure. The mean particle size of the perovskites increased with an increase in europium loading while the specific surface area decreased. Characterization data confirmed that a total insertion of Eu into LaFeO3 occurred at x ≤ 0.15. However, Eu2O3 segregation occurred to some extent especially at x >0.15. The catalytic activity of the catalysts increased substantially with an increase in Eu substitution in the evaluated range.
    Sulfur Resistance and Activity of Pt/CeO2-ZrO2-La2O3 Diesel Oxidation Catalysts
    ZHONG Fu-Lan, ZHONG Yu-Jiao, XIAO Yi-Hong, CAI Guo-Hui, ZHENG Yong, WEI Ke-Mei
    2011, 32 (9):  1469-1476.  DOI: 10.1016/S1872-2067(10)60259-8
    Abstract ( 3396 )   [Full Text(HTML)] () PDF (835KB) ( 1106 )  
    Three Pt/CeO2-ZrO2-La2O3 diesel oxidation catalysts were prepared by two different routes and characterized by X-ray diffraction, N2 adsorption, temperature-programmed reduction, temperature-programmed desorption, X-ray photoelectron spectroscopy, and infrared spectroscopy. The synthesis procedure affected the structure, texture, sulfur resistance, and catalytic activity of the catalysts. Sulfur poisoning increased the light-off temperature of all the catalysts, but the Pt/CeO2-ZrO2-La2O3 catalyst prepared by depositing ZrO2 and La2O3 on the surface of CeO2 nanoparticles exhibited better sulfur tolerance and catalytic activity with simulated diesel emission due to the high dispersion of Pt on CeO2-ZrO2-La2O3 oxide with a Zr-rich surface.
    Sulfuric Acid ([3-(3-Silicapropyl)sulfanyl]propyl)ester as a Recyclable Catalyst for the Synthesis of 4,4'-(Arylmethylene)bis(1H-pyrazol-5-ols)
    Shekoofeh TAYEBI, Mojtaba BAGHERNEJAD, Dariush SABERI, Khodabakhsh NIKNAM
    2011, 32 (9):  1477-1483.  DOI: 10.1016/S1872-2067(10)60260-4
    Abstract ( 3047 )   [Full Text(HTML)] () PDF (605KB) ( 1269 )  
    Sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl)ester is employed as a recyclable catalyst for the condensation reaction between aromatic aldehydes and 3-methyl-l-phenyl-5-pyrazolone. This condensation reaction was performed in ethanol under refluxing conditions giving 4,4'-alkylmethylene-bis(3-methyl-5-pyrazolones) in 74-90% yields. The heterogeneous catalyst was recycled and used in eleven runs for the reaction between benzaldehyde and 3-methyl-l-phenyl-5-pyrazolone without losing catalytic activity.
    Fe3O4 Nanoparticles as an Efficient and Magnetically Recoverable Catalyst for the Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones under Solvent-Free Conditions
    Masoud NASR-ESFAHANI, S. Jafar HOSEINI, Fatemeh MOHAMMADI
    2011, 32 (9):  1484-1489.  DOI: 10.1016/S1872-2067(10)60263-X
    Abstract ( 3140 )   [Full Text(HTML)] () PDF (857KB) ( 2021 )  
    The catalytic activity of Fe3O4 nanoparticles (NPs) in a one-pot three component condensation reaction consisting of an aromatic aldehyde, urea or thiourea, and a β-dicarbonyl under solvent-free conditions was investigated. This reaction affords the corresponding dihydropyrimidinones (thiones) in high to excellent yields. Compared with the classical Biginelli reactions this method consistently gives a high yield, easy magnetic separation, a short reaction time, and catalyst reusability.
    Asymmetric Hydrogenation of Aromatic Ketones Catalyzed by Achiral Monophosphine TPPTS-Stabilized Ru in PEG-Water
    QIN Rui-Xiang, WANG Jin-Bo, XIONG Wei, LIU De-Rong, FENG Jian, CHEN Hua
    2011, 32 (9):  1490-1495.  DOI: 10.3724/SP.J.1088.2011.10434
    Abstract ( 4033 )   [Full Text(HTML)] () PDF (430KB) ( 725 )  
    PEG-400 was found to be a green and recyclable reaction medium for asymmetric hydrogenation of aromatic ketones catalyzed by achiral monophosphine TPPTS (P(m-C6H4SO3Na)3), stabilized ruthenium modified by (1S,2S)-DPENDS (DPENDS: disodium salt of sulfonated (1S,2S)-1,2-diphenyl-1,2-ethylene-diamine). A 84.9% ee was obtained for acetophenone under the optimized conditions. The resulting products can be easily separated from the catalyst by extraction with n-hexane. The catalyst immobilized on PEG-400 not only exhibits excellent activity and enantioselectivity but also can be recycled and reused several times without loss of activity and enantioselectivity.
    Mesoporous Alumina Supported PdO Catalysts for Catalytic Combustion of Methane
    WANG Yue-Juan, GUO Mei-Na, LU Ji-Qing, LUO Meng-Fei
    2011, 32 (9):  1496-1501.  DOI: 10.3724/SP.J.1088.2011.10506
    Abstract ( 3177 )   [Full Text(HTML)] () PDF (955KB) ( 1064 )  
    Pd catalysts supported on mesoporous alumina (M-Al2O3) were prepared by an impregnation method and tested for CH4 catalytic combustion. PdO/M-Al2O3 was more active than the PdO catalyst supported on conventional Al2O3 because of a higher dispersion of PdO species induced by the mesoporous structure of M-Al2O3. Moreover, with increasing calcination temperature, the conversion of CH4 over PdO/M-Al2O3 catalysts first increased and then decreased. The best catalytic performance was obtained on the PdO/M-Al2O3 catalyst calcined at 700 oC, with a CH4 conversion of 91% at 400 oC. Pd species were mainly in mesoporous channels of the support in the form of highly dispersed PdO particles. When calcined at higher temperature, Pd species were in forms of crystalline Pd and PdO. A decline of reactivity and a higher turnover frequency were obtained on the PdO/M-Al2O3 catalyst calcined at 900 oC, which might be due to the co-existence of metallic Pd and PdO in the catalyst.
    Selective Catalytic Reduction of NO by CH4 in Combination of Non-thermal Plasma and Catalysts
    LIU Tong, YU Qin-Qin, WANG Hui, JIANG Xiao-Yuan, ZHENG Xiao-Ming
    2011, 32 (9):  1502-1507.  DOI: 10.3724/SP.J.1088.2011.10442
    Abstract ( 2969 )   [Full Text(HTML)] () PDF (769KB) ( 946 )  
    The selective catalytic reduction (SCR) of NO with CH4 was studied in combination of non-thermal plasma and catalysts. Among the series of metal oxides as catalysts, γ-Al2O3 exerts the highest activity. At 300 oC and the discharge power of 4.5 W, the NO conversion reaches 56.5% in the combination of plasma with γ-Al2O3, much higher than that in pure plasma mode (28.9%). At this temperature, no conversion of NO or CH4 was observed in pure catalytic reaction with γ-Al2O3 as the catalyst, indicating a synergistic function between the plasma and the catalyst. As further investigation shows, the catalytic activity has inverse correlation with dielectric constant on the whole. The porous structure and surface acidity of the catalysts obviously promote the plasma-assisted SCR of NO with CH4.
    Preparation of Molecularly Imprinted Polymer-Supported Gold Nanoparticles and Their Ability for Specific Substrate Recognition
    ZHU Zhen-Ke, TAN Rong, SUN Wen-Qing, YIN Dong-Hong
    2011, 32 (9):  1508-1512.  DOI: 10.3724/SP.J.1088.2011.10514
    Abstract ( 3214 )   [Full Text(HTML)] () PDF (594KB) ( 924 )  
    A molecularly imprinted polymer-supported gold nanoparticle (Au/MIP) catalyst, which has the characteristics of specific substrate recognition, was prepared by the template complex of 4-nitrobenzyl alcohol (4-NBA) and hydrogen tetrachloroaurate(III), where Au nanaoparticles were formed by the reduction with NaBH4 solution and captured by amino groups (-NH2) in the cavities of the MIP. The obtained samples were characterized with FT-IR spectroscopy, UV-Vis spectroscopy, and scanning electron microscopy. The catalytic activity and substrate recognition of the Au/MIP were investigated by the oxidation of substituted benzyl alcohol using H2O2 as the oxidant in water. It was found that the conversion of 4-NBA was up to 75.6% over Au/MIP when using the template molecule of 4-NBA as the substrate. However, the conversion of 4-NBA was only 41.5% over non-imprinted polymer-supported gold nanoparticle (Au/NIP) because no template molecule of 4-NBA was used in the preparation of catalyst. Furthermore, no significant difference of the catalytic activity between the catalysts Au/MIP and Au/NIP was observed when other substituted benzyl alcohols were used as the substrate. These results indicated that the catalytic activity of Au/MIP was related to the structure of substrates. The Au/MIP after removal of the template had molecular recognition shape and sites in the cavities matching to the substrate of 4-NBA molecule. The special recognizable cave of the Au/MIP exhibited unique substrate recognition and therefore improved the catalytic activity.
    Preparation and Photocatalytic Performance of Pt-TiNT@@SiO2 by UV Photoreduction
    WANG Sheng, GAO Yan-Long, WANG Tao, WANG Dong-Liang, DING Yuan-Wei, XU Xue-Fei, ZHANG Xiao-Long, JIANG Guo-Hua
    2011, 32 (9):  1513-1518.  DOI: 10.3724/SP.J.1088.2011.10501
    Abstract ( 3753 )   [Full Text(HTML)] () PDF (1168KB) ( 1140 )  
    The Pt nanoparticles-filled TiO2-semiconductor nanocomposite samples were prepared. By using SiO2-coated TiO2 nanotube (TiNT@@SiO2) as the support, Pt nanoparticles were successfully filled in TiNT@@SiO2 by a simple UV photoreduction method. The prepared Pt-TiNT@@SiO2 samples were characterized by transmission electron microscopy, field emission scanning electron microscopy, energy dispersive spectrometer, and X-ray diffraction. The photocatalytic activity of the samples for methanol oxidation shows that 1.5%Pt-TiNT@@SiO2 has the highest photo-activity. The mechanism of this inner-tube photocatalysis was discussed.
    The Performance of Carbon-Supported Platinum-Decorated Nickel Electrocatalyst for Ethanol Oxidation
    WANG Xing-Li, WANG Hui, LEI Zi-Qiang, ZHANG Zhe, WANG Rong-Fang
    2011, 32 (9):  1519-1524.  DOI: 10.3724/SP.J.1088.2011.10439
    Abstract ( 2884 )   [Full Text(HTML)] () PDF (550KB) ( 1269 )  
     A carbon-supported platinum-decorated nickel electrocatalyst (Ni@Pt/C) was prepared by two-step reaction and characterized by X-ray diffraction, transmission electron microscopy, and cyclic voltammetry. Based on the Pt mass, the Ni@Pt/C catalyst exhibits higher activity for ethanol oxidation than the commercial Pt/C catalyst and alloy PtNi/C catalyst. The peak current of Ni@Pt/C reaches 0.37 A/mg, which is 2.33 and 1.78 times as large as those of Pt/C and PtNi/C, respectively. This can be attributed to the modified electronic structure of the Pt surface layer in the Ni@Pt/C catalyst.
    Factors Influencing the Photoelectrocatalytic Reduction of Cr(VI) over TiO2 Nanotube Arrays
    WANG Qing, SHANG Jing, SONG Han
    2011, 32 (9):  1525-1530.  DOI: 10.3724/SP.J.1088.2011.10522
    Abstract ( 2616 )   [Full Text(HTML)] () PDF (512KB) ( 927 )  
    TiO2 nanotube (TNT) arrays present excellent light trapping and electronic conduction ability. TNT film was prepared by the anodic oxidation method using Ti slice as the substrate. The morphology and structure of the TNT film were characterized by scanning electron microscopy and X-ray diffraction, respectively. Photoelectrocatalytic (PEC) reduction of Cr(VI) was carried out using the TNT arrays as the photoanode and Ti mesh as the photocathode under acid conditions and ultraviolet light irradiation. The influencing factors such as applied voltage, NaCl concentration, citric acid concentration, and Cr(VI) initial concentration were investigated. The applied voltage facilitates the separation of electron-hole pairs, making the PEC reaction rate of Cr(VI) much higher than that of photocatalysis. The introduction of NaCl increases the electrical conductivity of solution, getting enhanced PEC reaction rate of Cr(VI) to some extent. Citric acid, behaving as the hole scavenger, can capture photogenerated holes effectively. The PEC reaction rate of Cr(VI) increases with increasing citric acid concentration in a certain range. Under the conditions of 1.5 V voltage, 1.0 mol/L NaCl, and 0.5 mmol/L citric acid, the conversion of 17.7 mg/L Cr(VI) achieved 98.6% at 60 min irradiation.
    Nano-lanthanum Oxyhalide Prepared by Nonaqueous Sol-Gel for Oxidative Coupling of Methane
    HOU Yu-Hui, CHANG Gang, WENG Wei-Zheng, XIA Wen-Sheng, WAN Hui-Lin
    2011, 32 (9):  1531-1536.  DOI: 10.3724/SP.J.1088.2011.10532
    Abstract ( 2830 )   [Full Text(HTML)] () PDF (456KB) ( 762 )  
    LaOX (X = Cl, Br) nanoparticles with tetragonal crystal structure were successfully prepared via sol-gel approach with non-aqueous solvents. Characterizations by X-ray powder diffraction and scanning electronic microscopy show that the LaOX nanoparticles are regularly in shape and highly uniform in size with an average diameter of about 47 nm. For oxidative coupling of methane (OCM), the nanosize LaOX catalysts have higher methane conversion and C2 selectivity than the LaOX catalysts with conventional size and show good stability in activity and selectivity during the catalyst life test at 650 °C. At conventional size, the methane conversion and C2 selectivity for OCM over the LaOBr catalyst are higher than that over the LaOCl catalyst, and at nanosize, there is not so much difference in methane conversion between LaOBr and LaOCl. However, the C2 selectivity for OCM reaction over LaOBr is significantly higher than that over LaOCl, especially at low temperature.
    Liquid-Phase Partial Hydrogenation of Benzene over Ru/MgAl2O4 Catalyst: Effect of Calcination Temperature of MgAl2O4
    ZHOU Gong-Bing, LIU Jian-Liang, XU Ke, PEI Yan, QIAO Ming-Hua, FAN Kang-Nian
    2011, 32 (9):  1537-1544.  DOI: 10.3724/SP.J.1088.2011.10508
    Abstract ( 2924 )   [Full Text(HTML)] () PDF (810KB) ( 1057 )  
    The MgAl2O4 material was synthesized by the hydrothermal method. A series of Ru/MgAl2O4 catalyst samples were prepared using this MgAl2O4 calcined at different temperatures. The catalyst samples were characterized by powder X-ray diffraction, 27Al solid-state nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, temperature-programmed reduction, temperature-programmed desorption, N2 physisorption, transmission electron microscopy, and X-ray photoelectron spectroscopy. It was found that the spinel phase readily formed at calcination temperature as low as 773 K. The calcination temperature of MgAl2O4 strongly influenced the structural properties of the catalyst. In the liquid-phase partial hydrogenation of benzene, the Ru/MgAl2O4 catalyst sample calcined at 1023 K exhibited the highest cyclohexene selectivity and yield. The maximum cyclohexene yield was 38.5% and the corresponding selectivity was 52.4%. Based on the characterization results, the effect of the calcination temperature of MgAl2O4 on the activity and selectivity of Ru/MgAl2O4 catalyst samples was discussed.
    Hydrogenolysis of Glycerol to 1,2-Propanediol over Ru/TiO2 Catalyst
    FENG Jian, XIONG Wei, JIA Yun, WANG Jin-Bo, LIU De-Rong, CHEN Hua, LI Xian-Jun
    2011, 32 (9):  1545-1549.  DOI: 10.3724/SP.J.1088.2011.10534
    Abstract ( 3006 )   [Full Text(HTML)] () PDF (371KB) ( 1388 )  
    The supported Ru/TiO2 catalyst was prepared by the impregnation method. The physicochemical properties of the catalyst were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, N2 adsorption, and inductively coupled plasma-atomic emission spectroscopy. The effects of reaction temperature, hydrogen pressure, glycerol concentration, catalyst amount, and base additives on the catalytic performance of Ru/TiO2 in the glycerol hydrogenolysis reaction were investigated. Under mild reaction conditions (170 oC, 3 MPa), using LiOH as additive, the conversion of glycerol and the selectivity for 1,2-propanediol were as high as 89.6% and 86.8%, respectively.
    Competitive Oxidation of N,N-Diethylamine with H2O2 Catalyzed by TS-1
    DENG Xiu-Juan, SHEN Lu, ZHANG Shuo, LIU Yue-Ming
    2011, 32 (9):  1550-1556.  DOI: 10.3724/SP.J.1088.2011.10543
    Abstract ( 3318 )   [Full Text(HTML)] () PDF (661KB) ( 1039 )  
    Oxidation of N,N-diethylamine (DEA) to N,N-diethylhydroxylamine (DEHA) in the catalytic system of TS-1/H2O2 has been studied. The competitive reactions between the oxidation of DEA and DEHA were further investigated. The results suggested that the conversion of DEA and effective utilization of H2O2 can be increased dramatically when H2O2 was added dropwise, while the mole ratio of DEA/H2O2 greatly influenced the selectivity for DEHA. TS-1 can catalyze the oxidation of DEA, as well as the oxidation of DEHA.
    Asymmetric Hydrolysis of Styrene Oxide Catalyzed by Mung Bean Epoxide Hydrolase in Organic Solvent/Buffer Biphasic System
    CHEN Wen-Jing, LOU Wen-Yong, WANG Xiao-Ting, ZONG Min-Hua
    2011, 32 (9):  1557-1563.  DOI: 10.3724/SP.J.1088.2011.10606
    Abstract ( 3142 )   [Full Text(HTML)] () PDF (796KB) ( 1057 )  
    The biocatalytic asymmetric hydrolysis of styrene oxide to (R)-1-phenyl-1,2-ethanediol catalyzed by Mung bean epoxide hydrolase in organic solvent/buffer biphasic systems was studied. In comparison with an aqueous monophasic system, the organic solvent/buffer biphasic system not only inhibited effectively the non-enzymatic hydrolysis of styrene oxide, but also markedly improved the substrate concentration, product yield, and product ee value. Among various organic solvents examined, the n-hexane was the most suitable organic phase for the reaction. In the n-hexane/buffer biphasic system, the initial reaction rate was clearly faster and the product yield and product ee value were much higher owing to the excellent solvent property of n-hexane for styrene oxide and relatively good biocompatibility with Mung bean epoxide hydrolase. Moreover, the optimal volume ratio of n-hexane to buffer, reaction temperature, buffer pH value, and substrate concentration for the enzymatic hydrolysis were found to be 1:1, 35 oC, 6.5, and 20 mmol/L, respectively, under which the initial reaction rate, the product yield, and the product ee value were 5.42 mmol/(L·h), 49.2%, and 94.3%, respectively.