الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
The aim of this research is to develop a computer program for determining the rate constants for the general form of any consecutive second order irreversible reaction at a certain temperature. Saponification of diethyl ester is considered throughout this work as an example of such reaction. The development of such program can be very helpful in the control of industrial processes as well as in the study of the reaction mechanisms.
First of all, ihe rate equations representing the reaction were specified, these equations result in a system of differential equations that need to be solved simultaneously. The integration of these equations using traditional methods is not an easy task and is time consuming. So, the numerical methods are introduced to solve such system approximately. Various methods are available, the best of which is the fourth order Runge - Kutta method.
in order to determine the rate constants of any reaction, a series of time -concentration data is required from laboratory data. Alternatively, we can simulate the reaction with the aid of computer software programs, and using known values of rate constants. The output of the simulation program is the time concentration data at any interval. These data are plotted and from the slopes of the curves the rate constants are recalculated. These are theoretical values; however, experimental data encounter several types of errors including temperature variation, impurities in the reactants, and human errors. So, we affect the theoretical data by random errors normally distributed with zero mean and suitable standard deviation in order to make the results noisy (experimental).
Finally, several optimization techniques are applied to the whole system in order to minimize the difference between the calculated (computer simulated) and experimental data, and therefore, calculating the optimum values of the rate constants. A comparison is made between these algorithms to find the best method for our case study in favor of accuracy and speed of convergence (least number of iterations).