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Abstract
On the basis of the theory of thermokinetics proposed in the literature, a novel thermokinetic method for determination of the reaction rate, the characteristic parameter method, is proposed in this paper. Mathematical models were established to determine the kinetic parameters and rate constants. In order to test the validity of this method, the saponifications of ethyl benzoate, ethyl acetate and ethyl propionate, and the formation of hexamethylenetetramine were studied with this method. The rate constants calculated with this method are in agreement with those in the literature, and the characteristic parameter method is therefore believed to be correct.In the light of the characteristic parameter method, we have developed further two thermo-kinetic methods, the thermoanalytical single and multi-curve methods, which are convenient for simultaneous determination of the reaction order and the rate constant. The reaction orders and rate constants of the saponifications of ethyl acetate and ethyl butyrate and the ring-opening reaction of epichlorohydrin with hydrobromic acid were determined with these methods, and their validity was verified by the experimental results.
Calculation of the kinetic parameters
Thermal decomposition of some phenol stabilizers on the basis of thermoanalytical data
The paper reports the calculation of kinetic parameters (activation energy, pre-exponent and reaction order) of thermodegradation of some phenol stabilizers. For this purpose, a software package for IBM-compatible personal computers is proposed. The first calculation of kinetic parameters (E, Z, n) was carried out for these compounds. The package can be applied for kinetic calculations on the thermodegradation of other substances.
Abstract
The thermal properties of four heteropoly complexes α-K3H3[SiW11Ni(H2O)O39]·11.5H2O (I), α-K3H2[SiW11Fe(H2O)O39]·9H2O (II), α-[(C4H9)4N]3.5H1.5[SiW11Fe(H2O)O39]·4.5H2O (III) and α-[(C4H9)4N]3.5H2.5[SiW11Cu(H2O)O39]·6H2O (IV) were studied by means of TG, DTA and DSC. The activation energy and reaction order of the thermal decomposition reaction of these complexes have been calculated.
Abstract
Interfacial tension dat for model 2-hydroxy-5-alkylbenzophenone E oximes at toluene/water interfaces was used to discuss different versions of the copper extraction mechanism. It was found that the interfacial tension isotherms are not specific enough to distinguish different interfacial behaviour of more and less hydrophobic hydroxyoximes, but if only the interfacial process is considered then the interfacial tension data demonstrate the extraction limiting step is the reaction between hydroxyoxime molecule present near the interface and the intermediate 1'1 complex. Only in this case are the predicted reaction orders aginst hydroxyoxime in agreement with order determined experimentally.
included the kinetic parameters and thermal reactivity properties [ 6 – 8 ], such as the kinetics of reaction, pre-exponential factor (ln k 0 ), reaction order ( n ), activation energy ( E a ), heat of decomposition (Δ H d ), isothermal time to maximum rate
Co-firing of biomass with coals
Part 2. Thermogravimetric kinetic analysis of co-combustion of fir (Abies bornmulleriana) wood with Beypazari lignite
a from the slope. To find out reaction order, Avrami theory [ 19 – 21 ] employed so as to describe the non-isothermal data where the variation of the degree of conversion with temperature and heating rate can be explained as 6 Taking
properties [ 7 , 10 , 11 ], such as the heat of decomposition (Δ H d ), reaction order ( n ), activation energy ( E a ), isothermal time to maximum rate (TMR iso ), time to conversion limit (TCL), self-accelerating decomposition temperature (SADT), control
Various carbon dust particles
Studies on thermal behaviour
-linear regression ( lines ) of ethene soot Activation energy, pre-exponential factor and reaction order were obtained by means of kinetic evaluation ( Table 1 ). Table 1
is obtained by linearization of Eq. 4 and making some rearrangements 5 The plot of ln(dα/d T ) − n ln(1 − α ) versus (1/ T ) should give a straight line for the correct value of reaction order n . Hence, several values of n were