KINETIC LAWS FOR SURFACE REACTIONS IN FLOW SYSTEMS

1958 ◽  
Vol 36 (7) ◽  
pp. 1081-1088 ◽  
Author(s):  
K. J. Laidler

A general differential equation is set up for the flow of reactant gases through a catalytic reactor, account being taken of changes in volume as the reaction proceeds and of the possibility that the catalyst surface is not completely available. Integrated solutions are given for three special cases and are presented in graphical form: (1) first-order reaction, the result being applicable whether the surface is completely available or not (Fig. 1); (2) second-order reaction with the surface completely available (Fig. 2); (3) second-order reaction with only a small fraction of the surface available (Fig. 3). The treatment is related to previous treatments of Hulburt, Thiele, and Wheeler.

1969 ◽  
Vol 47 (6) ◽  
pp. 873-877 ◽  
Author(s):  
Paul Allen Jr. ◽  
Patrick J. Conway

The sulfur–sulfur bond of α-disulfones is attacked by hydroxide ion in alcohol to yield sulfinate and sulfonate ion by a second-order reaction, first order in each of the reactants. With aromatic disulfones the ρ value of the Hammett equation is 0.2. The Arrhenius activation energy of the reaction of p-tolyl disulfone is 7.95 kcal/mole.


1985 ◽  
Vol 63 (4) ◽  
pp. 975-980 ◽  
Author(s):  
Guy Schmitz ◽  
Henri Rooze

The disproportionation of chlorite was studied in 0.01 to 1 M perchloric acid solutions at 25 °C and an ionic strength of 1 M. The results suggest at least three reaction paths. The first is catalysed by Cl− ions, the second gives a second-order rate law, and the third is catalysed by iron. Its rate law is[Formula: see text]This can be interpreted by the reversible reaction [Formula: see text] followed by two rate-determining reactions Fe2+ + HClO2 → products, [Formula: see text] From this study and the former, made with added ortho-tolidine, we conclude that the second-order reaction proceeds by a radical chain mechanism.


1971 ◽  
Vol 44 (4) ◽  
pp. 889-897 ◽  
Author(s):  
J. J. D'Amico ◽  
E. Morita

Abstract Evaluation of thiocarbamyl sulfenamides (I) prepared from 3-azabicyclo-(3.2.2) nonane and other amines indicates that the curing properties of stocks accelerated by (I) are influenced by the amino groups which constitute the thiocarbamyl and sulfenamide moieties, R and R′, respectively, and also vary with the formulation of the rubber stocks. The fastest cures are obtained when R is pyrrolidinyl or dimethyl and slowest cure when R′ is N-tert-butyl or N-morpholino. The lowest maximum crosslink density is obtained with morpholino- or piperidinothiocarbonyl sulfenamide. In a non-extended SBR black stock the crosslinking reaction generally proceeds as a second order reaction. The major part of the crosslinking reaction of the slower curing stocks proceeds by a fast first order rate followed by a slower first order rate.


1985 ◽  
Vol 50 (7) ◽  
pp. 1594-1601 ◽  
Author(s):  
Jiří Klíma ◽  
Larisa Baumane ◽  
Janis Stradinš ◽  
Jiří Volke ◽  
Romualds Gavars

It has been found that the decay in dimethylformamide and dimethylformamide-water mixtures of radical anions in five of the investigated 5-nitrofurans is governed by a second-order reaction. Only the decay of the radical anion generated from 5-nitro-2-furfural III may be described by an equation including parallel first- and second-order reactions; this behaviour is evidently caused by the relatively high stability of the corresponding dianion, this being an intermediate in the reaction path. The presence of a larger conjugated system in the substituent in position 2 results in a decrease of the unpaired electron density in the nitro group and, consequently, an increase in the stability of the corresponding radical anions.


1983 ◽  
Vol 48 (11) ◽  
pp. 3279-3286
Author(s):  
Slavko Hudeček ◽  
Miloslav Bohdanecký ◽  
Ivana Hudečková ◽  
Pavel Špaček ◽  
Pavel Čefelín

The reaction between hexamethylenediisocyanate and 1-pentanol in toluene was studied by means of reversed-phase liquid chromatography. By employing this method, it was possible to determine all components of the reaction mixture including both products, i.e. N-(6-isocyanate hexyl)pentylcarbamate and N,N'-bis(pentyloxycarbonyl)hexamethylenediamine. Relations for the calculation of kinetic constants were derived assuming a competitive consecutive second-order reaction. It was demonstrated that the reaction involved in this case is indeed a second-order reaction, and the rate constants of the first and second consecutive reactions were determined.


2003 ◽  
Vol 35 (6) ◽  
pp. 246-251
Author(s):  
A. E. Croce ◽  
L. V. Mogni ◽  
C. Vicente Irrazábal

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