Kinetics of formation of ethylene oxide hydrate. Part I. Experimental method and congruent solutions

1968 ◽  
Vol 46 (24) ◽  
pp. 3857-3865 ◽  
Author(s):  
D. N. Glew ◽  
M. L. Haggett
Keyword(s):  
Heat Transfer ◽  
Ethylene Oxide ◽  
Experimental Method ◽  
Hydrate Formation ◽  
Controlling Factor ◽  
Oxide Hydrate ◽  
Mechanical Stirring ◽  
Magnetic Stirring ◽  
Kinetics Of Formation ◽  
Kinetics Of

A dilatometer was constructed for studying the formation of ethylene oxide hydrate. In unstirred, congruent solutions heat transfer appeared to be the significant rate-controlling factor. Initial hydrate formation rates were independent of stirring at speeds greater than approximately 100 r.p.m. Magnetic stirring was inadequate due to hydrate build-up on the walls of the dilatometer bulb. Mechanical stirring eliminated this build-up and gave satisfactory results.

Kinetics of formation of ethylene oxide hydrate. Part II. Incongruent solutions and discussion

1968 ◽  
Vol 46 (24) ◽  
pp. 3867-3877 ◽  
Author(s):  
D. N. Glew ◽  
M. L. Haggett
Keyword(s):  
Heat Conduction ◽  
Ethylene Oxide ◽  
Oxide Hydrate ◽  
Early Stages ◽  
Kinetics Of Formation ◽  
Kinetics Of

Equations were developed to describe the experimental rates of formation of ethylene oxide hydrate from stirred, incongruent solutions. Heat conduction through the walls of the dilatometer bulb was rate-controlling. Results for congruent solutions were consistent with these equations during the early stages of hydrate growth.

Aqueous nonelectrolyte solutions. Part XIII. Ice and hydrate freezing points of aqueous ethylene oxide solutions and the formula of congruent ethylene oxide hydrate

1995 ◽  
Vol 73 (6) ◽  
pp. 788-796 ◽  
Author(s):  
David N. Glew ◽  
Norman S. Rath
Keyword(s):  
Ethylene Oxide ◽  
Standard Error ◽  
Hydrate Formation ◽  
Standard Errors ◽  
Single Measurement ◽  
Method Of Least Squares ◽  
Oxide Hydrate ◽  
Dynamic Cooling ◽  
Freezing Temperatures ◽  
Freezing Curve

Ice freezing temperatures and hydrate formation temperatures have been measured by the dynamic cooling method for aqueous ethylene oxide (EO) solutions containing from 0 to 95 mol% EO. The ice and the congruent hydrate freezing temperatures exhibited standard errors on a single measurement of 0.004 °C and 0.013 °C, respectively. The ice–hydrate eutectic temperature was observed at −2.107 °C with standard error 0.001 °C and composition 1.991 mol% EO with standard error 0.008 mol% EO. The congruent hydrate was found to freeze at 11.083 °C with standard error 0.002 °C and composition 12.64 mol% EO with standard error 0.02 mol% EO. The formula of the congruent hydrate was EO•6.91H2O with standard error 0.013 mol water/mol EO. Only a single hydrate was found over the whole composition range down to −26 °C: the shoulder of the hydrate freezing curve above 40 mol% EO resulted from the high activity coefficients to dilute water in concentrated EO solutions. Equations and best values for the ice freezing temperatures and the hydrate formation temperatures together with their standard errors were evaluated by the method of least squares. Keywords: clathrate hydrate of ethylene oxide, freezing of water – ethylene oxide, ethylene oxide hydrate.

Experimental Study on the Effect of Gas Hydrate Content on Heat Transfer

2015 ◽  
Author(s):  
Remi-Erempagamo T. Meindinyo ◽  
Runar Bøe ◽  
Thor Martin Svartås ◽  
Silje Bru
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Ethylene Oxide ◽  
Deep Water ◽  
Gas Hydrate ◽  
Atmospheric Pressure ◽  
Methane Hydrate ◽  
Hydrate Formation ◽  
Equilibrium Temperature ◽  
Gas Hydrate Formation

Gas hydrates are the foremost flow assurance issue in deep water operations. Since heat transfer is a limiting factor in gas hydrate formation processes, a better understanding of its relation to hydrate formation is important. This work presents findings from experimental study of the effect of gas hydrate content on heat transfer through a cylindrical wall. The experiments were carried out at temperature conditions similar to those encountered in flowlines in deep water conditions. Experiments were conducted on methane hydrate, Tetrahydrofuran hydrate, and ethylene oxide hydrate respectively in stirred cylindrical high pressure autoclave cells. Methane hydrate was formed at 90 bars (pressure), and 8°C, followed by a cooling/heating cycle in the range of 8°C → 4°C → 8°C. Tetrahydrofuran (THF) and ethylene oxide (EO) hydrates were formed at atmospheric pressure and system temperature of 1°C in contact with atmospheric air. This was followed by a heating/cooling cycle within the range of 1°C → 4°C → 1°C, since the hydrate equilibrium temperature of THF hydrate is 4.98°C in contact with air at atmospheric pressure. The experimental conditions of the latter hydrate formers were more controlled, given that both THF and EO are miscible with water. We found in all cases a general trend of decreasing heat transfer coefficient of the cell content with increasing concentration of hydrate in the cell, indicating that hydrate formation creates a heat transfer barrier. The hydrate equilibrium temperature seemed to change with a change in the stoichiometric concentration of THF and EO. While the methane hydrate cooling/heating cycles were performed under quiescent conditions, the effect of stirring was investigated for the latter hydrate formers.

scholarly journals Effect of thermal formation/dissociation cycles on the kinetics of formation and pore-scale distribution of methane hydrates in porous media: a magnetic resonance imaging study

2021 ◽  
Vol 5 (5) ◽  
pp. 1567-1583 ◽  
Author(s):  
Mehrdad Vasheghani Farahani ◽  
Xianwei Guo ◽  
Lunxiang Zhang ◽  
Mingzhao Yang ◽  
Aliakbar Hassanpouryouzband ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Hydrate Formation ◽  
Imaging Study ◽  
Magnetic Resonance Imaging Study ◽  
Resonance Imaging ◽  
Natural Sediment ◽  
Thermally Induced ◽  
Kinetics Of Formation ◽  
Kinetics Of

A magnetic resonance imaging study was conducted to explore the kinetics and spatial characteristics of the thermally induced methane hydrate formation in both synthetic and natural sediment samples.

Kinetics of cyclization of S-ethoxycarbonylmethylisothiouronium chloride to 2-imino-4-thiazolidone

1979 ◽  
Vol 44 (3) ◽  
pp. 912-917 ◽  
Author(s):  
Vladimír Macháček ◽  
Said A. El-bahai ◽  
Vojeslav Štěrba
Keyword(s):  
Hydrochloric Acid ◽  
Dilute Hydrochloric Acid ◽  
Base Catalysis ◽  
General Base ◽  
Rate Limiting Step ◽  
Limiting Step ◽  
Kinetics Of Formation ◽  
Acid Catalyzed ◽  
Rate Limiting ◽  
Kinetics Of

Kinetics of formation of 2-imino-4-thiazolidone from S-ethoxycarbonylmethylisothiouronium chloride has been studied in aqueous buffers and dilute hydrochloric acid. The reaction is subject to general base catalysis, the β value being 0.65. Its rate limiting step consists in acid-catalyzed splitting off of ethoxide ion from dipolar tetrahedral intermediate. At pH < 2 formation of this intermediate becomes rate-limiting; rate constant of its formation is 2 . 104 s-1.

Cyclization and acid-catalyzed hydrolysis of O-benzoylbenzamidoximes

1986 ◽  
Vol 51 (12) ◽  
pp. 2786-2797
Author(s):  
František Grambal ◽  
Jan Lasovský
Keyword(s):  
Reaction Rate ◽  
Kinetic Isotope ◽  
Acid Base Equilibrium ◽  
Mineral Acids ◽  
Kinetics Of Formation ◽  
Acid Catalyzed ◽  
Ph Scale ◽  
Kinetics Of ◽  
Hydrolysis Of ◽  
Derivatives Of

Kinetics of formation of 1,2,4-oxadiazoles from 24 substitution derivatives of O-benzoylbenzamidoxime have been studied in sulphuric acid and aqueous ethanol media. It has been found that this medium requires introduction of the Hammett H0 function instead of the pH scale beginning as low as from 0.1% solutions of mineral acids. Effects of the acid concentration, ionic strength, and temperature on the reaction rate and on the kinetic isotope effect have been followed. From these dependences and from polar effects of substituents it was concluded that along with the cyclization to 1,2,4-oxadiazoles there proceeds hydrolysis to benzamidoxime and benzoic acid. The reaction is thermodynamically controlled by the acid-base equilibrium of the O-benzylated benzamidoximes.

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