Catalyzed Oxidation of Cyclohexane over Co-Bi2(MoO4)3 Catalysts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.550-553.354 ◽

2012 ◽

Vol 550-553 ◽

pp. 354-357

Author(s):

Su Ling Gao ◽

Tai Xuan Jia ◽

Zi Li Liu

Keyword(s):

Experimental Data ◽

Liquid Phase ◽

Selective Oxidation ◽

Atomic Ratio ◽

Precipitation Method ◽

Micro Structure ◽

Cooperative Effects ◽

Catalyzed Oxidation

The effect of catalyst on the performance of liquid-phase selective oxidation of cyclohexane as probe reaction over Co-Bi2(MoO4)3 prepared by precipitation method was investigated. The catalyst evaluation results show that the optimum catalyst atomic ratio is n(Mo):n(Bi):n(Co)=1.5:1:0.2 with high selecivity under certain conversion. Meanwhile selective oxidation of Bi2(MoO4)3 was slowed down, selecivity of cyclohexanone and cyclohexanol reached 74.1%, 22.2% respectively.The main composition of the catalyst is Bi2(MoO4)3. Co-Bi2(MoO4)3 had new catalyst sites with Bi3+, Mo6+ and Co2+ having a cooperative effects during oxidation of cyclohexane. Under this condition, selecivity of cyclohexanone improved greatly. Micro-structure and essence disciplinarian of Co-Bi2(MoO4)3 were disclosed by XRD and FTIR. This study could provide experimental data for the technical reform of industry equipment.

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Chemical Reduction of Titania Supported Gold by Glycerol

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d1157.1284s219 ◽

2019 ◽

Vol 8 (4S2) ◽

pp. 477-481

Keyword(s):

Liquid Phase ◽

Selective Oxidation ◽

Chemical Reduction ◽

Precipitation Method ◽

Small Particles ◽

Tio2 Sample ◽

Supported Gold Catalysts ◽

Oxidation Performance ◽

Supported Gold ◽

Size Controlled

Gold was loaded on TiO2 by deposition precipitation method (DPU). The as prepared DPU samples were reduced in the liquid phase through chemical reduction with pure glycerol. The advantage of this method is that, the formation of small particles (less than 7 nm) can be prevented. The chemically reduced 0.93% Au/TiO2 sample exhibited an average gold size of 12.6  0.92 nm while, the H2-reduced counterpart showed 4.2  0.25 nm. The efficacy of the size-controlled catalyst was demonstrated in the selective oxidation of HMF. The chemically reduced samples exhibited excellent selective oxidation performance by forming exclusively one product. This study reveals the possibility of controlling the size of metal-oxide supported gold catalysts.

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Unravelling the radical transition during the carbon-catalyzed oxidation of cyclohexane by in situ electron paramagnetic resonance in the liquid phase

Catalysis Science & Technology ◽

10.1039/c7cy00958e ◽

2017 ◽

Vol 7 (19) ◽

pp. 4431-4436 ◽

Cited By ~ 9

Author(s):

Xixian Yang ◽

Yonghai Cao ◽

Hao Yu ◽

Hongyu Huang ◽

Hongjuan Wang ◽

...

Keyword(s):

Electron Paramagnetic Resonance ◽

Liquid Phase ◽

Selective Oxidation ◽

Chemical Industry ◽

Paramagnetic Resonance ◽

Oxidation Of Hydrocarbons ◽

Electron Paramagnetic ◽

Catalyzed Oxidation

The selective oxidation of hydrocarbons is of great importance in the chemical industry.

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Theoretical analysis of counter-current absorption of a poorly soluble gas based on the PDE-AD model

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19861222 ◽

1986 ◽

Vol 51 (6) ◽

pp. 1222-1239 ◽

Cited By ~ 1

Author(s):

Pavel Moravec ◽

Vladimír Staněk

Keyword(s):

Experimental Data ◽

Liquid Phase ◽

Gas Phase ◽

Transfer Functions ◽

Packed Bed ◽

Packed Bed Column ◽

Interfacial Transport ◽

Gaseous Component ◽

Poorly Soluble ◽

Counter Current

Expression have been derived in the paper for all four possible transfer functions between the inlet and the outlet gas and liquid steams under the counter-current absorption of a poorly soluble gas in a packed bed column. The transfer functions have been derived for the axially dispersed model with stagnant zone in the liquid phase and the axially dispersed model for the gas phase with interfacial transport of a gaseous component (PDE - AD). calculations with practical values of parameters suggest that only two of these transfer functions are applicable for experimental data evaluation.

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Effect of ionizing radiation on the kinetics of hydrogenation on the Ni-MgO mixed catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19821780 ◽

1982 ◽

Vol 47 (7) ◽

pp. 1780-1786 ◽

Cited By ~ 2

Author(s):

Rostislav Kudláček ◽

Jan Lokoč

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Liquid Phase ◽

Ionizing Radiation ◽

Oxide Catalyst ◽

Absorbed Dose ◽

Hydrogenation Rate ◽

Solution Composition ◽

Mixed Catalyst ◽

Kinetics Of

The effect of gamma pre-irradiation of the mixed nickel-magnesium oxide catalyst on the kinetics of hydrogenation of maleic acid in the liquid phase has been studied. The changes of the hydrogenation rate are compared with the changes of the adsorbed amount of the acid and with the changes of the solution composition, activation energy, and absorbed dose of the ionizing radiation. From this comparison and from the interpretation of the experimental data it can be deduced that two types of centers can be distinguished on the surface of the catalyst under study, namely the sorption centres for the acid and hydrogen and the reaction centres.

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Metal-Organic Frameworks in Oxidation Catalysis with Hydrogen Peroxide

Catalysts ◽

10.3390/catal11020283 ◽

2021 ◽

Vol 11 (2) ◽

pp. 283

Author(s):

Oxana Kholdeeva ◽

Nataliya Maksimchuk

Keyword(s):

Hydrogen Peroxide ◽

Liquid Phase ◽

Selective Oxidation ◽

Metal Organic Frameworks ◽

Short Review ◽

Catalytic Performance ◽

Oxidation Catalysis ◽

Catalyst Stability ◽

Aqueous Hydrogen Peroxide ◽

Metal Organic

In recent years, metal–organic frameworks (MOFs) have received increasing attention as selective oxidation catalysts and supports for their construction. In this short review paper, we survey recent findings concerning use of MOFs in heterogeneous liquid-phase selective oxidation catalysis with the green oxidant–aqueous hydrogen peroxide. MOFs having outstanding thermal and chemical stability, such as Cr(III)-based MIL-101, Ti(IV)-based MIL-125, Zr(IV)-based UiO-66(67), Zn(II)-based ZIF-8, and some others, will be in the main focus of this work. The effects of the metal nature and MOF structure on catalytic activity and oxidation selectivity are analyzed and the mechanisms of hydrogen peroxide activation are discussed. In some cases, we also make an attempt to analyze relationships between liquid-phase adsorption properties of MOFs and peculiarities of their catalytic performance. Attempts of using MOFs as supports for construction of single-site catalysts through their modification with heterometals will be also addressed in relation to the use of such catalysts for activation of H2O2. Special attention is given to the critical issues of catalyst stability and reusability. The scope and limitations of MOF catalysts in H2O2-based selective oxidation are discussed.

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Effect of Surfactants on Gas Holdup in Shear-Thinning Fluids

International Journal of Chemical Engineering ◽

10.1155/2017/9062649 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Shaobai Li ◽

Siyuan Huang ◽

Jungeng Fan

Keyword(s):

Experimental Data ◽

Liquid Phase ◽

Sodium Dodecyl ◽

Shear Thinning ◽

Gas Holdup ◽

Bubble Columns ◽

Gas Velocity ◽

Shear Thinning Fluids ◽

Liquid Surface Tension ◽

Superficial Gas Velocity

In this study, the gas holdup of bubble swarms in shear-thinning fluids was experimentally studied at superficial gas velocities ranging from 0.001 to 0.02 m·s−1. Carboxylmethyl cellulose (CMC) solutions of 0.2 wt%, 0.6 wt%, and 1.0 wt% with sodium dodecyl sulfate (SDS) as the surfactant were used as the power-law (liquid phase), and nitrogen was used as the gas phase. Effects of SDS concentration, rheological behavior, and physical properties of the liquid phase and superficial gas velocity on gas holdup were investigated. Results indicated that gas holdup increases with increasing superficial gas velocity and decreasing CMC concentration. Moreover, the addition of SDS in CMC solutions increased gas holdup, and the degree increased with the surfactant concentration. An empirical correlation was proposed for evaluating gas holdup as a function of liquid surface tension, density, effective viscosity, rheological property, superficial gas velocity, and geometric characteristics of bubble columns using the experimental data obtained for the different superficial gas velocities and CMC solution concentrations with different surfactant solutions. These proposed correlations reasonably fitted the experimental data obtained for gas holdup in this system.

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Technological Features of the Liquid-Solid State of the Boundary Layer in the Processes of Bimetallic Products

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1049.53 ◽

2022 ◽

Vol 1049 ◽

pp. 53-61

Author(s):

Valeriy Lykhoshva ◽

Dmitry Glushkov ◽

Elena Reintal ◽

Valeriy V. Savin ◽

Ludmila Alexeyevna Savina ◽

...

Keyword(s):

Mathematical Modeling ◽

Experimental Data ◽

Boundary Layer ◽

Solid State ◽

Liquid Phase ◽

Contact Zone ◽

Thermal Field ◽

Thermal State ◽

Existence Time ◽

Modeling Data

The hydrodynamic and thermal state in the contact zone of the layers of a bimetallic product obtained by pouring liquid iron onto a solid steel billet, which changes in time and is responsible for the strength of the diffusion joint and the geometric parameters of the transition layer, has been investigated. Simplified analytical dependences, mathematical modeling data and experimental results of the liquid phase existence time in the contact zone based on research of the melt velocities during pouring and changes in the thermal field are presented. It is shown that simplified calculations data coincide in order and are close in values to the calculations of mathematical modeling and experimental data, which makes it possible to use them for preliminary rough estimates by technologists and metallurgists.

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Application of a Bubble-Induced Turbulence Model to Subcooled Boiling in a Vertical Pipe

10.1115/imece1999-1253 ◽

1999 ◽

Author(s):

Mahmut D. Mat ◽

Yüksel Kaplan ◽

Olusegun J. Ilegbusi

Keyword(s):

Experimental Data ◽

Mathematical Model ◽

Liquid Phase ◽

Turbulence Model ◽

Transport Equations ◽

Subcooled Boiling ◽

Vertical Pipe ◽

Void Fractions ◽

Turbulence Production ◽

The Mathematical Model

Abstract Subcooled boiling of water in a vertical pipe is numerically investigated. The mathematical model involves solution of transport equations for vapor and liquid phase separately. Turbulence model considers the turbulence production and dissipation by the motion of the bubbles. The radial and axial void fractions, temperature and velocity profiles in the pipe are calculated. The estimated results are compared to experimental data available in the literature. It is found that while present study satisfactorily agrees with experimental data in the literature, it improves the prediction at lower void fractions.

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