Noncatalytic Liquid Phase Air Oxidation of Ethylbenzene to 1-Phenyl Ethyl Hydroperoxide in Low Oxygen Volume Fraction

2018 ◽  
Vol 22 (2) ◽  
pp. 136-146 ◽  
Author(s):  
Hossein Roohi ◽  
Mehrdad Rajabi
Keyword(s):  
Liquid Phase ◽  
Volume Fraction ◽  
Air Oxidation ◽  
Low Oxygen ◽  
Oxidation Of Ethylbenzene

scholarly journals Quantification of shear viscosity and wall slip velocity of highly concentrated suspensions with non-Newtonian matrices in pressure driven flows

2021 ◽  
Author(s):  
Patrick Wilms ◽  
Jan Wieringa ◽  
Theo Blijdenstein ◽  
Kees van Malssen ◽  
Reinhard Kohlus
Keyword(s):  
Shear Stress ◽  
Liquid Phase ◽  
Shear Rate ◽  
Shear Viscosity ◽  
Slip Velocity ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Wall Slip ◽  
Flow Index ◽  
Concentrated Suspensions

AbstractThe rheological characterization of concentrated suspensions is complicated by the heterogeneous nature of their flow. In this contribution, the shear viscosity and wall slip velocity are quantified for highly concentrated suspensions (solid volume fractions of 0.55–0.60, D4,3 ~ 5 µm). The shear viscosity was determined using a high-pressure capillary rheometer equipped with a 3D-printed die that has a grooved surface of the internal flow channel. The wall slip velocity was then calculated from the difference between the apparent shear rates through a rough and smooth die, at identical wall shear stress. The influence of liquid phase rheology on the wall slip velocity was investigated by using different thickeners, resulting in different degrees of shear rate dependency, i.e. the flow indices varied between 0.20 and 1.00. The wall slip velocity scaled with the flow index of the liquid phase at a solid volume fraction of 0.60 and showed increasingly large deviations with decreasing solid volume fraction. It is hypothesized that these deviations are related to shear-induced migration of solids and macromolecules due to the large shear stress and shear rate gradients.

Solid–liquid–liquid phase envelopes from temperature-scanned refractive index data

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Alcides J. Sitoe ◽  
Franco Pretorius ◽  
Walter W. Focke ◽  
René Androsch ◽  
Elizabeth L. du Toit
Keyword(s):  
Refractive Index ◽  
Liquid Phase ◽  
Volume Fraction ◽  
Solution Temperature ◽  
Linear Behavior ◽  
Upper Critical Solution Temperature ◽  
Novel Method ◽  
Using Data ◽  
Solid Liquid ◽  
Liquid Liquid Phase Separation

Abstract A novel method for estimating the upper critical solution temperature (UCST) of N,N-diethyl-m-toluamide (DEET)-polyethylene systems was developed. It was validated using data for the dimethylacetamide (DMA)-alkane systems which showed that refractive index mixing rules, linear in volume fraction, can accurately predict mixture composition for amide-alkane systems. Furthermore, rescaling the composition descriptor with a single adjustable parameter proved adequate to address any asymmetry when modeling the DMA-alkane phase envelopes. This allowed the translation of measured refractive index cooling trajectories of DEET-alkane systems into phase diagrams and facilitated the estimation of the UCST values by fitting the data with an adjusted composition descriptor model. For both the DEET- and DMA-alkane systems, linear behavior of UCST values in either the Flory–Huggins critical interaction parameter, or the alkane critical temperature, with increasing alkane molar mass is evident. The UCST values for polymer diluent systems were estimated by extrapolation using these two complimentary approaches. For the DEET-polyethylene system, values of 183.4 and 180.1 °C respectively were obtained. Both estimates are significantly higher than the melting temperature range of polyethylene. Initial liquid–liquid phase separation is therefore likely to be responsible for the previously reported microporous microstructure of materials formed from this binary system.

Study on the Composites of Phenol Formaldehyde Resin/Graphite Reinforced by Milled Carbon Fibers for Bipolar Plates

2010 ◽  
Vol 156-157 ◽  
pp. 1090-1096
Author(s):  
Wei Qiang Wang ◽  
Ai Ju Li ◽  
Ming Ming You ◽  
Bin Xia
Keyword(s):  
Electrical Conductivity ◽  
Liquid Phase ◽  
Flexural Strength ◽  
Carbon Fibers ◽  
Phenol Formaldehyde ◽  
Resin Content ◽  
Liquid Phase Oxidation ◽  
Bipolar Plates ◽  
Air Oxidation ◽  
Phase Oxidation

Composites of phenol formaldehyde (PF) resin/graphite reinforced by milled carbon fibers (MCFs) for bipolar plates are obtained by hot compression molding. The raw materials of the MCF particles, PF resin powder and graphite powder are simply dry powder ball milled and mixed. The effects of PF resin content and the content, granularity and surface treatment methods, such as air oxidation and Fenton/ultraviolet (UV) liquid-phase oxidation of MCFs on the electrical conductivity and flexural strength of the composites are measured by methods of four-point probe technique and three point flexural test, and the fracture patterns of the composites are analyzed by scanning electron microscope (SEM). The results indicate that the electrical conductivity decreases and flexural strength increases with the increase of PF resin content. Especially, the values of electrical conductivity and flexural strength can reach 165.28 S.cm-1 and 55.11MPa respectively when the PF resin content was 17% in weight. The properties of composites reinforced by air oxidation treated MCFs are better than those by liquid-phase oxidation treated one. The electrical conductivity and flexural strength of the composites are 208.12S.cm-1 and 57.44 MPa when they reinforced by 5% MCFs which treated by air oxidation at 450 . Compared with the nonreinfoced composites, the properties of reinforced composites increase 25.92% in electrical conductivity and 4.23% in flexural strength.

Heterogeneous Cobalt−Saponite Catalyst for Liquid Phase Air Oxidation ofp-Cresol

2009 ◽  
Vol 48 (21) ◽  
pp. 9423-9427 ◽  
Author(s):  
Vikas S. Kshirsagar ◽  
Ajit C. Garade ◽  
Kashinath R. Patil ◽  
Ratnesh K. Jha ◽  
Chandrashekhar V. Rode
Keyword(s):  
Liquid Phase ◽  
Air Oxidation

Activity of Manganese Carboxylates in the Process of Liquid-Phase Oxidation of Ethylbenzene with Atmospheric Oxygen

2021 ◽  
Vol 899 ◽  
pp. 215-219
Author(s):  
Rinat Mukhamedzyanov ◽  
Zufar Muzipov ◽  
The Son Pham ◽  
Elina Vasilyeva ◽  
Raisa Akhmedyanova
Keyword(s):  
Liquid Phase ◽  
Oxidation Reaction ◽  
Atmospheric Oxygen ◽  
Liquid Phase Oxidation ◽  
Phase Oxidation ◽  
Oxidation Of Ethylbenzene ◽  
Variable Valency

The process of oxidation of hydrocarbon with oxygen proceeds with formation of the corresponding hydroperoxide as the primary product [1,2]. A catalyst is the most important factor that influences on the direction of flow of the oxidation reaction. Catalysts based on metals of variable valency, and their derivatives are the most active in reactions of oxidation of hydrocarbon [3].

Determination of Methanol Concentration in Ethanol in Liquid Phase by a Phononic Crystal Mach-Zehnder Interferometer

2021 ◽  
Author(s):  
Aysevil Salman Durmuşlar ◽  
Emine Ates ◽  
Ahmet Biçer ◽  
Sualp Deniz ◽  
Ahmet Cicek ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Liquid Phase ◽  
Volume Fraction ◽  
Phononic Crystal ◽  
High Sensitivity ◽  
Zehnder Interferometer ◽  
Pure Ethanol ◽  
Interferometric Sensor ◽  
Polyethylene Tubing

Abstract A practical and portable ultrasonic interferometric sensor to detect methanol concentration in ethanol in the liquid phase is numerically investigated. For high-sensitivity operation, the sensor is designed as a Mach-Zehnder interferometer based on a linear-defect waveguide in a two-dimensional phononic crystal, which consists of square array of cylindrical steel rods in water. The waveguide core comprises polyethylene tubing, impedance-matched with water, filled with either pure ethanol or ethanol-methanol binary mixture, allowing fast replacement of the analyte. Band structure analyses through the finite-element method are carried out to obtain guiding modes at frequencies around 200 kHz. With 50x21 cells with 4.2 mm periodicity, the total sensor area is 210-by-88.2 millimeters, which can be significantly reduced by increasing the operating frequency to megahertz range. The interferometer is constructed via T junctions of the waveguide, which facilitates low-loss equal splitting and recollection of ultrasonic waves. Sample and reference wave paths are constructed by filling polyethylene tubing on the upper and lower halves of the interferometer with the ethanol-methanol mixture and pure ethanol, respectively. Frequency-domain finite-element method simulations reveal that the sensor output is characterized by several transmission peaks, one of which is centered at 203.35 kHz with a full-width at half-maximum of 20 Hz, resulting in a quality factor of 10167. The peak frequency of this peak redshifts at a rate of 7.24 Hz per percent volume fraction change in methanol. The peak shift is linear when the methanol volume fraction is below 10%. Besides, the interferometric sensor has a figure of merit around 0.35. The proposed ultrasonic sensor offers rapid detection of methanol content in ethanol with high sensitivity.

Active Form of the Catalyst for the Liquid Phase Air Oxidation of Hydrocarbons

1965 ◽  
Vol 8 (6) ◽  
pp. 442-446
Author(s):  
Yoshinobu Takegami ◽  
Yoshikazu Fujimura ◽  
Kosaku Kamio
Keyword(s):  
Liquid Phase ◽  
Active Form ◽  
Air Oxidation ◽  
Oxidation Of Hydrocarbons

Liquid phase oxidation of ethylbenzene on pure and metal doped HS-AlF3

2008 ◽  
Vol 10 (2) ◽  
pp. 227-231 ◽  
Author(s):  
Irmina K. Murwani ◽  
Kerstin Scheurell ◽  
Erhard Kemnitz
Keyword(s):  
Liquid Phase ◽  
Liquid Phase Oxidation ◽  
Phase Oxidation ◽  
Oxidation Of Ethylbenzene ◽  
Metal Doped
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