THE REACTIONS OF ACTIVE NITROGEN WITH THE BUTANES

1954 ◽  
Vol 32 (7) ◽  
pp. 718-724 ◽  
Author(s):  
R. A. Back ◽  
C. A. Winkler
Keyword(s):  
Nitrogen Atom ◽  
Rate Constants ◽  
Hydrogen Cyanide ◽  
Main Product ◽  
Activation Energies ◽  
Reactive Species ◽  
Atomic Nitrogen ◽  
Initial Attack ◽  
Active Nitrogen ◽  
Rate Controlling Step

The main product of the reactions of active nitrogen with n- and iso-butanes at 75 °C. and 250 °C. was hydrogen cyanide. Small amounts of C2 hydrocarbons, mainly ethylene and acetylene, were produced in both reactions. Second order rate constants were calculated on the assumption that the reactive species in active nitrogen is atomic nitrogen, and that the initial attack of a nitrogen atom is the rate-controlling step. The activation energies were then estimated to be 3.6 kcal. and 3.1 kcal. and the probability factors 4.5 × 10−4 and 4.4 × 10−4, for the n-butane and isobutane reactions respectively.

THE REACTION OF ACTIVE NITROGEN WITH PROPYLENE

1952 ◽  
Vol 30 (12) ◽  
pp. 915-921 ◽  
Author(s):  
G. S. Trick ◽  
C. A. Winkler
Keyword(s):  
Double Bond ◽  
Nitrogen Atom ◽  
Hydrogen Cyanide ◽  
Atomic Hydrogen ◽  
Atomic Nitrogen ◽  
Active Nitrogen

The reaction of nitrogen atoms with propylene has been found to produce hydrogen cyanide and ethylene as the main products, together with smaller amounts of ethane and propane and traces of acetylene and of a C4 fraction. With excess propylene, the nitrogen atoms were completely consumed and for the reaction at 242 °C., 0.77 mole of ethylene was produced for each mole of excess propylene added. For reactions at lower temperatures, less ethylene was produced. The proposed mechanism involves formation of a complex between the nitrogen atom and the double bond of propylene, followed by decomposition to ethylene, hydrogen cyanide, and atomic hydrogen. The ethylene would then react with atomic nitrogen in a similar manner.

THE REACTION OF ACTIVE NITROGEN WITH AZOMETHANE

1955 ◽  
Vol 33 (11) ◽  
pp. 1649-1655 ◽  
Author(s):  
D. A. Armstrong ◽  
C. A. Winkler
Keyword(s):  
Hydrogen Cyanide ◽  
Activation Energies ◽  
Methyl Radicals ◽  
Atomic Nitrogen ◽  
Reactive Component ◽  
Active Nitrogen ◽  
Steric Factors ◽  
Unstable Product

The main products of the reaction between active nitrogen and azomethane were hydrogen cyanide and ethane. Traces of methane, ethylene, and acetylene were also formed, together with small amounts of an unstable product. Activation energies of about 0.5 ± 0.4 and 1.9 ± 0.3 kcal. per mole, with corresponding steric factors of 10−1 to 10−3 and 10−2 to 10−4, were estimated for the reactions of active nitrogen with methyl radicals and azomethane respectively, on the assumption that atomic nitrogen is the reactive component of active nitrogen. Azomethane appeared to catalyze the deactivation of active nitrogen.

THE REACTION OF ACTIVE NITROGEN WITH PROPANE

1954 ◽  
Vol 32 (4) ◽  
pp. 351-355 ◽  
Author(s):  
M. Onyszchuk ◽  
L. Breitman ◽  
C. A. Winkler
Keyword(s):  
Activation Energy ◽  
Flow Rate ◽  
Rate Constants ◽  
Hydrogen Cyanide ◽  
Main Product ◽  
Second Order ◽  
Steric Factor ◽  
Active Nitrogen ◽  
Flow Rates ◽  
Order Rate

The reaction of nitrogen atoms with propane has been found to produce hydrogen cyanide as the main product, together with smaller amounts of acetylene, ethylene, and ethane, which were recovered at all propane flow rates. Complete consumption of nitrogen atoms was not attained at any propane flow rate used at 63 °C, but was attained at 250 °C for ratios of propane to nitrogen atoms greater than 1.3. An activation energy of 5.6 ± 0.6 kcal. and a steric factor between 10−2 and 10−3 was estimated from second order rate constants.

THE RATE OF REACTION OF ACTIVE NITROGEN WITH ETHANE, PROPANE, AND NEOPENTANE

1964 ◽  
Vol 42 (8) ◽  
pp. 1948-1956 ◽  
Author(s):  
W. E. Jones ◽  
C. A. Winkler
Keyword(s):  
Rate Constants ◽  
Reaction Times ◽  
Reactive Species ◽  
Hydrogen Atoms ◽  
Active Nitrogen ◽  
Probe Technique ◽  
Temperature Range ◽  
Excited Species ◽  
Rate Of Reaction ◽  
Dual Activation

The reactions of active nitrogen with ethane, propane, and neopentane have been studied over the temperature range 0 to 450 °C. A cobalt probe technique was used to stop the reactions after various reaction times. Second order rate constants have been calculated on the assumption that nitrogen atoms are the only reactive species in active nitrogen. Broken Arrhenius lines were obtained for both the ethane and neopentane reactions but this behavior was not observed with the propane reaction. The dual activation energies have been attributed to a mechanism involving initiation by both excited molecules and either nitrogen or hydrogen atoms. Methods are outlined by which an estimate has been made of the concentration of excited species assumed to be involved in the ethane reaction.

THE REACTIONS OF ACTIVE NITROGEN WITH ALKYL CHLORIDES

1956 ◽  
Vol 34 (8) ◽  
pp. 1074-1082 ◽  
Author(s):  
B. Dunford ◽  
H. G. V. Evans ◽  
C. A. Winkler
Keyword(s):  
Hydrogen Cyanide ◽  
Methyl Chloride ◽  
The Other ◽  
Alkyl Chloride ◽  
Initial Attack ◽  
Fast Reaction ◽  
Ethyl Vinyl ◽  
Active Nitrogen ◽  
Flow Rates ◽  
Reactant Flow

The reactions of active nitrogen with methyl, ethyl, vinyl, propyl, and isopropyl chlorides yielded hydrogen cyanide and hydrogen chloride as the main products. Small amounts of cyanogen and a polymer were formed from all the halides, and all except methyl chloride also yielded small amounts of C2 and C3 hydrocarbons. The observed changes in amounts of products recovered with different reactant flow rates were characteristic of a fast reaction in which complete consumption of either reactant occurs when the other is present in excess. Mechanisms for the reactions are suggested on the basis that relatively long-lived complexes are formed in the initial attack of a nitrogen atom on the alkyl chloride.

THE REACTION OF NITROGEN ATOMS WITH OXYGEN ATOMS IN THE ABSENCE OF OXYGEN MOLECULES

1961 ◽  
Vol 39 (8) ◽  
pp. 1601-1607 ◽  
Author(s):  
C. Mavroyannis ◽  
C. A. Winkler
Keyword(s):  
Nitric Oxide ◽  
Nitrogen Atom ◽  
Rate Constant ◽  
Rate Constants ◽  
Flow System ◽  
Titration Method ◽  
Active Nitrogen ◽  
Reaction Tube ◽  
Fast Flow ◽  
Oxygen Atoms

The reaction has been studied in a fast-flow system by introducing nitric oxide in the gas stream with excess active nitrogen. The nitrogen atom consumption was determined by titrating active nitrogen with nitric oxide at different positions along the reaction tube. The rate constant is found to be k1 = 1.83(± 0.2) × 1015 cc2 mole−2 sec−1 at pressures of 3, 3.5, and 4 mm, and with an unheated reaction tube.The homogeneous and surface decay of nitrogen atoms involved in the above system were studied using the nitric oxide titration method, and the rate constants were found to be k3 = 1.04 ± 0.17 × 1016 cc2 mole−2 sec−1, and k4 = 2.5 ± 0.2 sec−1 (γ = 7.5 ± 0.6 × 10–5), respectively, over the range of pressures from 0.5 to 4 mm with an unheated reaction tube.

scholarly journals THE REACTION OF NITROGEN ATOMS WITH METHANE AND ETHANE

1951 ◽  
Vol 29 (11) ◽  
pp. 1010-1021 ◽  
Author(s):  
H. Blades ◽  
C. A. Winkler
Keyword(s):  
Activation Energy ◽  
Nitrogen Atom ◽  
High Temperatures ◽  
Hydrogen Cyanide ◽  
Active Species ◽  
Second Order ◽  
Steric Factor ◽  
Atomic Nitrogen ◽  
Atom Concentration ◽  
Nitrogen Stream

Methane reacted with nitrogen atoms at temperatures above 300°C. to produce hydrogen cyanide. An activation energy of 11 kcal. and a steric factor of 5 × 10−3 were obtained. The reaction of ethane with nitrogen atoms was studied up to 295°C., with hydrogen cyanide the only product found in measurable amounts. At high temperatures, nitrogen atom consumption was complete in excess ethane, and the hydrogen cyanide production under these conditions, compared with the atom concentration determined by a Wrede gauge, indicated the active species in the nitrogen stream to be only atomic nitrogen. The ethane – nitrogen atom reaction was second order, with an activation energy of 7 ± 1 kcal. and a steric factor between 10−1 and 10−3.

The Reactions of Active Nitrogen with Simple Alcohols

1973 ◽  
Vol 51 (22) ◽  
pp. 3671-3679 ◽  
Author(s):  
John M. Roscoe ◽  
Sharon G. Roscoe
Keyword(s):  
Isotope Effect ◽  
Rate Constants ◽  
Initial Step ◽  
Activation Energies ◽  
Active Nitrogen ◽  
Activated State ◽  
Small Primary

The reactions of active nitrogen with CH3OH, C2H5OH, n-C3H7OH and iso-C3H7OH have been studied as a function of temperature. The rate constants for these reactions fit the following expressions:[Formula: see text](Activation energies are in kJ/mol. Rate constants are in 1 mol−1 s−1.)Experiments with CH3OH, CH3OD, and CD3OD indicate a small primary isotope effect for OH and a secondary isotope effect for CH. This, with other data, implies that abstraction of a H atom from the alcohol is not an important initial step.Consumption of N atoms ranged from 4.7 to 7.1 times the alcohol consumed. With the exception of the reaction of active nitrogen with iso-C3H7OH, the only detectable stable reaction product was HCN. Intervention of O atoms as intermediates appears to be important in all the reactions. In the reaction of active nitrogen with iso-C3H7OH, acetone, and acetonitrile were also found as products in amounts of about 26% and 14% respectively of the HCN yield. These products appear to arise through O atom intervention.Mechanisms for the reactions and the nature of the activated state in the initial step are discussed.

Kinetics of esterification of monoisopropylphenols with phosphoryl trichloride

1989 ◽  
Vol 54 (5) ◽  
pp. 1311-1317
Author(s):  
Miroslav Magura ◽  
Ján Vojtko ◽  
Ján Ilavský
Keyword(s):  
Liquid Phase ◽  
Rate Constants ◽  
Reaction Rates ◽  
Activation Energies ◽  
The Individual ◽  
Kinetics Of

The kinetics of liquid-phase isothermal esterification of POCl3 with 2-isopropylphenol and 4-isopropylphenol have been studied within the temperature intervals of 110 to 130 and 90 to 110 °C, respectively. The rate constants and activation energies of the individual steps of this three-step reaction have been calculated from the values measured. The reaction rates of the two isomers markedly differ: at 110 °C 4-isopropylphenol reacts faster by the factors of about 7 and 20 for k1 and k3, respectively. This finding can be utilized in preparation of mixed triaryl phosphates, since the alkylation mixture after reaction of phenol with propene contains an excess of 2-isopropylphenol over 4-isopropylphenol.

scholarly journals Kinetics and Mechanism of the Change of the 4-Nitrobenzylthio-System into 4,4′-Diformylazoxybenzene in Alkaline Dioxane-Water Media

1985 ◽  
Vol 40 (11) ◽  
pp. 1128-1132
Author(s):  
Y. Riad ◽  
Adel N. Asaad ◽  
G.-A. S. Gohar ◽  
A. A. Abdallah
Keyword(s):  
Acetic Acid ◽  
Sodium Hydroxide ◽  
Rate Constants ◽  
Main Product ◽  
Reaction Medium ◽  
Aqueous Dioxane ◽  
Proton Abstraction ◽  
First Order ◽  
Water Media ◽  
Different Temperatures

Sodium hydroxide reacts with α -(4-nitrobenzylthio)-acetic acid in aqueous-dioxane media to give 4,4'-diformylazoxybenzene as the main product besides 4,4'-dicarboxyazoxybenzene and a nitrone acid. This reaction was kinetically studied in presence of excess of alkali in different dioxane-water media at different temperatures. It started by a fast reversible a-proton abstraction step followed by two consecutive irreversible first-order steps forming two intermediates (α -hydroxy, 4-nitrosobenzylthio)-acetic acid and 4-nitrosobenzaldehyde. The latter underwent a Cannizzaro's reaction, the products of which changed in the reaction medium into 4,4'-diformylazoxybenzene and 4,4'-dicarboxyazoxybenzene. The rate constants and the thermodynamic parameters of the two consecutive steps were calculated and discussed. A mechanism was put forward for the formation of the nitrone acid.Other six 4-nitrobenzyl, aryl sulphides were qualitatively studied and they gave mainly 4,4'-diformylazoxybenzene beside 4,4'-dicarboxyazoxybenzene or its corresponding azo acid.

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