Ultrasound and ionic liquid-enhanced extractive desulfurization of diesel

The current desulfurization technology, hydrodesulfurization (HDS), is energy intensive, uses large quantities of hydrogen, and is ineffective at removing some sulfur compounds. Ionic liquids have been recently shown to perform well as extraction solvents for the removal of sulfur from diesel. However, a major limitation towards their industrial use is the low mass transfer rates that result from their relatively high viscosities. This study investigates the use of ultrasound to overcome this problem. The ionic liquid, 1-ethyl-3-methylimidazolium acetate ([C2mim][CH3COO]), was used to desulfurize model diesel consisting of dibenzothiophene in hexadecane, in the absence and presence of ultrasound. It was found that sonification can greatly enhance the rate of mass transfer of DBT from diesel to the IL, resulting in a 57% sulfur removal for a 75% decrease in extraction time for batch studies, which results in a reduction in the number of equilibrium stages necessary for a continuous extraction process.

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SWSex Stars, Old Novae, and the Evolution of Cataclysmic Variables

Acta Polytechnica CTU Proceedings ◽

10.14311/app.2015.02.0188 ◽

2015 ◽

Vol 2 (1) ◽

pp. 188-191 ◽

Cited By ~ 2

Author(s):

L. Schmidtobreick ◽

C. Tappert

Keyword(s):

Mass Transfer ◽

Transfer Rate ◽

Mass Transfer Rate ◽

Cataclysmic Variables ◽

High Mass ◽

Period Range ◽

Transfer Rates ◽

Low Mass ◽

Orbital Periods ◽

Nova Outburst

The population of cataclysmic variables with orbital periods right above the period gap are dominated by systems with extremely high mass transfer rates, the so-called SW Sextantis stars. On the other hand, some old novae in this period range which are expected to show high mass transfer rate instead show photometric and/or spectroscopic resemblance to low mass transfer systems like dwarf novae. We discuss them as candidates for so-called hibernating systems, CVs that changed their mass transfer behaviour due to a previously experienced nova outburst. This paper is designed to provide input for further research and discussion as the results as such are still very preliminary.

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Desulfurization Of The Dibenzothiophene (DBT) By Using Imidazolium-Based Ionic Liquids(Ils)

Materials Physics and Chemistry ◽

10.18282/mpc.v1i2.571 ◽

2019 ◽

Vol 1 (2) ◽

pp. 1

Author(s):

Bilal Kazmi ◽

Awan Zahoor ◽

Hashmi Saud ◽

Zafar Khan Ghouri

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Process Condition ◽

Chemical Properties ◽

Aspen Plus ◽

Extraction Process ◽

Simulation Software ◽

Liquid Fuels ◽

Process Conditions ◽

Model Diesel

In this work we examined the industrial scale extraction process of ultra-low sulfur diesel with the help of simulation software ASPEN Plus®. This work focuses on the [Cnmim] [BF4] (imidazolium-based) ionic liquid and employed it in the extractive desulfurization of the dibenzothiophene (DBT) from the model diesel fuel under a very mild process condition. UNIFAC (uniquasi functional activity) was chosen as the thermodynamic method to model the ionic liquid on ASPEN Plus® and different physical and chemical properties were then taken from the literature to be incorporated in the simulation model. Different parametric analysis was studied for the removal of thiophene-based compounds from the model diesel. The results acquired shows the significance of imidazolium-based ionic liquids (ILs) for the extraction of S-contents from the liquid fuels at an optimal process conditions of 40 ℃ and 2 bar pressure with the 2.8: 1 ratio of ionic liquid and model diesel which validates the experimental results obtained previously in the literature.

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The Evolution of Binary Stars into Contact States

International Astronomical Union Colloquium ◽

10.1017/s0252921100087881 ◽

1989 ◽

Vol 107 ◽

pp. 289-297

Author(s):

R W Hilditch

Keyword(s):

Mass Transfer ◽

Binary Stars ◽

Light Curves ◽

Transfer Rates ◽

Empirical Results ◽

Short Period ◽

Contact Binaries ◽

Low Mass ◽

Evolutionary Paths ◽

First Time

AbstractGood-quality empirical results on 62 short-period binary stars recently summarised by Hilditch & Bell (1987) and Hilditch, King & McFarlane (1988) are discussed in terms of evolutionary paths from detached to semi-detached and contact states. These data suggest two evolutionary paths to the contact binaries - from detached systems directly into contact to form initially shallow-contact systems, and via case A mass transfer to semi-detached states, thence to contact systems. These empirical results support previous arguments based on evolutionary models and less detailed observational data.Concern is expressed about the paucity of high-quality spectroscopic data, particularly for low-mass systems displaying EB-type light curves and the resultant limitations on analyses of those light curves. Such systems provide tests of evolution into contact for the first time, or of broken-contact phases for WUMa-type binaries. The crucial importance of long-term monitoring (decades) of times of minima as indicators of mass transfer rates amongst these interacting binaries is also noted.

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EIS Investigation of Zinc Electrodeposition in Basic Media at Low Mass Transfer Rates Induced by a Magnetic Field

The Journal of Physical Chemistry B ◽

10.1021/jp9835263 ◽

1999 ◽

Vol 103 (3) ◽

pp. 496-501 ◽

Cited By ~ 23

Author(s):

Olivier Devos ◽

Omar Aaboubi ◽

Jean Paul Chopart ◽

Etienne Merienne ◽

Alain Olivier ◽

...

Keyword(s):

Magnetic Field ◽

Mass Transfer ◽

Transfer Rates ◽

Zinc Electrodeposition ◽

Low Mass

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Enhancement of Carbon Dioxide Mass Transfer Rate by (Ionic Liquid)-in-Water Emulsion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.113 ◽

2014 ◽

Vol 881-883 ◽

pp. 113-117

Author(s):

Hong Jing Liu ◽

Yang Pan ◽

Hui Yao ◽

Ying Zhang

Keyword(s):

Carbon Dioxide ◽

Aqueous Solution ◽

Mass Transfer ◽

Ionic Liquid ◽

Mass Transfer Rate ◽

Continuous Phase ◽

Water Emulsion ◽

Transfer Rates ◽

Shuttle Effect ◽

Methyl Imidazole

Effects of dispersed ionic liquid (IL) on physical absorption of CO2in aqueous solution were investigated in the study. IL-in-water emulsion had been prepared, whose continuous phase was surfactant aqueous solution, and dispersed phase was an ionic liquid, 1-octyl-3 methyl imidazole hexafluoride phosphate. The morphololgy of dispersion had been observed by visual method. The CO2concentrations in the bulk of the absorption solvent were calculated. Results show that the enhancement of carbon dioxide mass transfer was realized by IL-in-water emulsion. The reason for the increase of CO2mass transfer rates by dispersed ionic liquid has been attributed to the increase of mass transfer driving force depending on shuttle effect.

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Investigating the Proton and Ion Transfer Properties of Supported Ionic Liquid Membranes Prepared for Bioelectrochemical Applications Using Hydrophobic Imidazolium-Type Ionic Liquids

Membranes ◽

10.3390/membranes11050359 ◽

2021 ◽

Vol 11 (5) ◽

pp. 359

Author(s):

László Koók ◽

Piroska Lajtai-Szabó ◽

Péter Bakonyi ◽

Katalin Bélafi-Bakó ◽

Nándor Nemestóthy

Keyword(s):

Mass Transfer ◽

Ionic Liquid ◽

Ionic Liquids ◽

Microbial Fuel Cells ◽

Transport Numbers ◽

Liquid Membranes ◽

Ion Transfer ◽

Supported Ionic Liquid ◽

Supported Ionic Liquid Membranes ◽

Transfer Properties

Hydrophobic ionic liquids (IL) may offer a special electrolyte in the form of supported ionic liquid membranes (SILM) for microbial fuel cells (MFC) due to their advantageous mass transfer characteristics. In this work, the proton and ion transfer properties of SILMs made with IL containing imidazolium cation and [PF6]− and [NTf2]− anions were studied and compared to Nafion. It resulted that both ILs show better proton mass transfer and diffusion coefficient than Nafion. The data implied the presence of water microclusters permeating through [hmim][PF6]-SILM to assist the proton transfer. This mechanism could not be assumed in the case of [NTf2]− containing IL. Ion transport numbers of K+, Na+, and H+ showed that the IL with [PF6]− anion could be beneficial in terms of reducing ion transfer losses in MFCs. Moreover, the conductivity of [bmim][PF6]-SILM at low electrolyte concentration (such as in MFCs) was comparable to Nafion.

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Effects of Variable Transport Properties on Heat and Mass Transfer in MHD Bioconvective Nanofluid Rheology with Gyrotactic Microorganisms: Numerical Approach

Coatings ◽

10.3390/coatings11020231 ◽

2021 ◽

Vol 11 (2) ◽

pp. 231

Author(s):

Muhammad Awais ◽

Saeed Ehsan Awan ◽

Muhammad Asif Zahoor Raja ◽

Nabeela Parveen ◽

Wasim Ullah Khan ◽

...

Keyword(s):

Mass Transfer ◽

Transport Properties ◽

Heat And Mass Transfer ◽

Group Analysis ◽

Numerical Approach ◽

Validity Of Results ◽

Gyrotactic Microorganisms ◽

Transfer Rates ◽

Buongiorno’S Model ◽

Density Distributions

Rheology of MHD bioconvective nanofluid containing motile microorganisms is inspected numerically in order to analyze heat and mass transfer characteristics. Bioconvection is implemented by combined effects of magnetic field and buoyancy force. Gyrotactic microorganisms enhance the heat and transfer as well as perk up the nanomaterials’ stability. Variable transport properties along with assisting and opposing flow situations are taken into account. The significant influences of thermophoresis and Brownian motion have also been taken by employing Buongiorno’s model of nanofluid. Lie group analysis approach is utilized in order to compute the absolute invariants for the system of differential equations, which are solved numerically using Adams-Bashforth technique. Validity of results is confirmed by performing error analysis. Graphical and numerical illustrations are prepared in order to get the physical insight of the considered analysis. It is observed that for controlling parameters corresponding to variable transport properties c2, c4, c6, and c8, the velocity, temperature, concentration, and bioconvection density distributions accelerates, respectively. While heat and mass transfer rates increases for convection parameter and bioconvection Rayleigh number, respectively.

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Prediction of Growth Parameters of Frost Deposits in Forced Convection

Journal of Heat Transfer ◽

10.1115/1.3244426 ◽

1981 ◽

Vol 103 (1) ◽

pp. 3-6 ◽

Cited By ~ 17

Author(s):

J. E. White ◽

C. J. Cremers

Keyword(s):

Mass Transfer ◽

Forced Convection ◽

Growth Parameters ◽

Experimental Investigations ◽

Experimental Conditions ◽

Transfer Rates ◽

Air Stream ◽

Transient Period ◽

Approximate Expressions ◽

Frost Layer

Experimental investigations of frost deposition under forced convection conditions have shown that in most cases heat and mass transfer rates become constant after an initial transient period. It is shown that, in such cases, approximately half of the mass transfer from a humid air stream to a frost layer diffuses inward, condenses and increases the density of the frost. The other half is deposited at the surface and increases the thickness of the layer. Approximate expressions for density and thickness of the frost layer are derived and compared with data from the literature and also with experimental work reported in this paper. The correlations are shown to work well for a broad range of experimental conditions.

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