الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
For chemical reactions, the determination of the rate constants is both very difficult and
a time consuming process. The aim of this research work is to develop computer programs
for determining the rate constants for the general form of any complex reaction at a certain
temperature. 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. Determination of
the accurate values of the rate constants would help in establishing the optimum
conditions of reactor design including pressure, temperature, and other parameters of the
chemical reaction.
from the experimental concentration-time data, initial values of rate constants are
calculated. Experimental data encountered several types of errors, including temperature
variation, impurities in the reactants, and human errors. Simulation of a second order
consecutive irreversible chemical reaction of the saponification of diethyl ester are
presented as an example of the complex reactions. The rate equations (system of simultaneous differential equations) of the reaction are solved to get the analytical
concentration versus time profiles. The simulation results are compared with experimental
results at each measured point. All deviations between experimental and calculated values
are squared and summed up to form a new function. This function is fed into a minimizer
routine that gives the optimal rate constants. Three optimization techniques are developed
using FORTRAN, MATLAB and VISUAL BASIC for accurately determining the rate
constants of the reaction at certain temperature from the experimental data.
Results show that the proposed programs are very efficient, fast, and accurate tools to
determine the true rate constants of the reaction. The use of the MA TLAB embedded
subroutines for simultaneously solving the differential equations and minimization of the
error function is very fast in solving such problems, as compared to the FORTRAN
program, which, although resulting in fast and accurate results, yet, requiring the use of a
library of external subroutines. The VISUAL BASIC excels in its visualization framework
and user friendly interface.
Any of the proposed methodologies could be used to determine the rate constants of any complex reaction at a certain temperature. The proposed programs are independent of
the nature of the reaction, only the rate equations and the initial conditions had to be
modified for any new reaction.