scholarly journals THE PHOTOLYSIS OF METHYL ETHYL KETONE

1955 ◽  
Vol 33 (6) ◽  
pp. 1062-1068 ◽  
Author(s):  
P. Ausloos ◽  
E. W. R. Steacie
Keyword(s):  
Activation Energy ◽  
Methyl Ethyl Ketone ◽  
Methyl Ethyl ◽  
Ethyl Radical

Methyl ethyl ketone has been photolyzed at temperatures between 25° and 240 °C., at varying pressures and intensities. Azomethane has also been photolyzed in the presence of methyl ethyl ketone. It is concluded that the ratio of disproportionation to recombination for a methyl and an ethyl radical is of the order of 0.04. The activation energy for the abstraction of hydrogen from the ketone by methyl is 7.4 ± 0.1 kcal., and by ethyl it is 8.0 ± 0.1 kcal.

Hemolytic decomposition of di-sec-butyl peroxide

1970 ◽  
Vol 48 (4) ◽  
pp. 615-627 ◽  
Author(s):  
R. Hiatt ◽  
Sandor Szilagyi
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Hydrogen Production ◽  
Methyl Ethyl Ketone ◽  
Methyl Ethyl ◽  
Kcal Mole ◽  
Alkoxy Radicals ◽  
Solvent Cage ◽  
Butyl Peroxide

Rates and products have been determined for the thermal decomposition of sec-butyl peroxide at 110–150 °C in several solvents.The decomposition was shown to be unimolecular with energies of activation in toluene, benzene, and cyclohexane of 35.5 ± 1.0, 33.2 ± 1.0, 33.8 ± 1.0 kcal/mole respectively. The activation energy of thermal decomposition for the deuterated peroxide was found to be 37.2 + 1.0 kcal/mole in toluene.About 70–80% of the products could be explained by known reactions of free alkoxy radicals, and very little, if any, disproportionation of two sec-butoxy radicals in the solvent cage could be detected.The other 20–30% of the peroxide yielded H2 and methyl ethyl ketone. The yield of H2 was unaffected by the nature or the viscosity of the solvent, but H2 was not formed when s-Bu2O2 was photolyzed in toluene at 35 °C nor when the peroxide was thermally decomposed in the gas phase.α,α′-Dideutero-sec-butyl peroxide was prepared and decomposed in toluene at 110–150 °C. The yield of D2 was about the same as the yield of H2 from s-Bu2O2, but the rate of decomposition (at 135 °C) was only 1/1.55 as fast.Mechanisms for hydrogen production are discussed, but none satisfactorily explains all the evidence.

Highly efficient synthesis of methyl ethyl ketone oxime through ammoximation over Ti-MOR catalyst

2014 ◽  
Vol 34 (1) ◽  
pp. 243-250
Author(s):  
Jianghong DING ◽  
Le XU ◽  
Hao XU ◽  
Haihong WU ◽  
Yueming LIU ◽  
...  
Keyword(s):  
Methyl Ethyl Ketone ◽  
Methyl Ethyl ◽  
Efficient Synthesis ◽  
Highly Efficient

Electroinduced oxidative copolymerization ofN-vinyl carbazole with methyl ethyl ketone formaldehyde resin

2004 ◽  
Vol 15 (7) ◽  
pp. 365-369 ◽  
Author(s):  
Belkıs Ustamehmetoğlu ◽  
A. Sezai Saraç ◽  
Nilgün Kızılcan ◽  
Ahmet Akar
Keyword(s):  
Methyl Ethyl Ketone ◽  
Formaldehyde Resin ◽  
Methyl Ethyl ◽  
Oxidative Copolymerization

scholarly journals Lipozyme 435-Mediated Synthesis of Xylose Oleate in Methyl Ethyl Ketone

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3317
Author(s):  
Maria Carolina Pereira Gonçalves ◽  
Jéssica Cristina Amaral ◽  
Roberto Fernandez-Lafuente ◽  
Ruy de Sousa Junior ◽  
Paulo Waldir Tardioli
Keyword(s):  
Oleic Acid ◽  
Methyl Ethyl Ketone ◽  
Molar Ratio ◽  
Methyl Ethyl ◽  
Sugar Ester ◽  
Molar Ratios ◽  
Emulsion Capacity ◽  
Ping Pong ◽  
Commercial Sugar ◽  
Repeated Use

In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates’ molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.

scholarly journals Effect of Sonic Agitation of a Binary Mixture of Solvents on Filling Remnants Removal as an Alternative to Apical Enlargement—A Micro-CT Study

2020 ◽  
Vol 9 (8) ◽  
pp. 2465
Author(s):  
Inês Ferreira ◽  
Pedro S. Babo ◽  
Ana Cristina Braga ◽  
Manuela E. Gomes ◽  
Irene Pina-Vaz
Keyword(s):  
Binary Mixture ◽  
Methyl Ethyl Ketone ◽  
Solvent Mixture ◽  
Methyl Ethyl ◽  
Micro Computed Tomography ◽  
Significance Level ◽  
Root Canals ◽  
Gutta Percha ◽  
Ah Plus ◽  
Mandibular Incisors

Background: This work aimed to evaluate the efficacy of sonic agitation of a binary mixture of solvents (methyl ethyl ketone/tetrachloroethylene) on filling remnants removal and compare the effects of solvent agitation with the enlargement to the next instrument size. Methods: Twenty-four mandibular incisors were prepared with ProTaper Next (X1, X2) and obturated with the single-cone technique and AH Plus sealer. The teeth were retreated with ProTaper Universal Retreatment and ProTaper Next and divided into two groups (n = 12) according to the final instrument (X3 or X4). All canals were submitted to a supplementary procedure consisting of a mixture of solvents―methyl ethyl ketone/tetrachloroethylene, agitated with EndoActivator. The volume of filling remnants was assessed through micro-computed tomography in the apical 5 mm. Statistical analysis was performed with a significance level of 5%. Results: The supplementary procedure of agitation of the solvent mixture was beneficial in both groups (p < 0.05). There were no statistically significant differences between canals re-prepared until X4 and canals re-prepared until X3 plus solvent (p > 0.05). Conclusions: An additional step with a two-solvent solution potentiated by EndoActivator showed to be very effective for the removal of gutta-percha and resinous sealer remnants from apical root canals of mandibular incisors, avoiding further enlargement.

Pervaporation for the Separation of Methyl Ethyl Ketone from Binary Process Mixtures

1997 ◽  
Vol 32 (6) ◽  
pp. 1127-1142
Author(s):  
C. S. Slater ◽  
K. M. Devine ◽  
A. J. Meier
Keyword(s):  
Methyl Ethyl Ketone ◽  
Methyl Ethyl ◽  
Binary Process
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