Advisor: Professor Rayford G. Anthony
CoAdvisor: Professor Gilbert F. Froment

This research project focuses on the development of kinetic models for the main catalytic reactions on the commercial potassium-promoted iron oxide catalyst with the excess of steam and for the coke formation and gasification on the catalyst during the ethylbenzene dehydrogenation.

A set of experiments has been carried out over the catalyst in the tubular reactor under the atmospheric pressure. Typical reaction conditions are 620oC, steam/ethylbenzene mole ratio of 11, and partial pressure of N2 diluent of 0.432 bar. Experimental data have been obtained with different operating conditions, e.g., temperatures, feeding ratios of ethylbenzene, steam, hydrogen, and styrene, and space times to estimate kinetic parameters for the main reaction (ethylbenzene dehydrogenation) and side reactions (benzene and toluene formations). The surface reaction on the catalyst surface is assumed to be the rate controlling step. The thermal cracking reactions which take place in the zones without catalyst and in the void sections of the catalyst bed are taken into account for the kinetic modeling as well.

The data analysis is based upon the integral method of kinetic analysis as described by Froment (1975, 1990). The intrinsic kinetic parameter values are estimated through the minimization of the objective function utilizing the Marquardt algorithm. The t-test is performed to test the statistical significance of each parameter.

Bibliography

Froment, G. F., Model discrimination and parameter estimation in heterogeneous catalysis. AIChE Journal 21, 1041 (1975)

Froment, G. F.; Bischoff, K. B. Chemical reactor analysis and design. 2nd ed. John Wiley & Sons, New York (1990)