| The catalytic cracking of hydrocarbons proceeds through a complex reaction networks, involving hundreds of components. When the feed is a complex mixture, containing thousands of hydrocarbons, the number of components in the reaction mixture becomes enormous and the generation of reaction network for each of the feed components, accounting for the elementary steps and single events involved, becomes a challenging task. This dissertation deals with the computer generation of the reaction network of olefins, developing a molecular level kinetic model.The kinetic model was built using the single-event concept, based on the well-known carbenium ion mechanism. The experiment was carried on the fixed bed reaction chromatograph equipment on ZSM-5 catalyst. As the limited channel of ZSM-5 zeolite can inhibit the bimolecular process, the catalytic cracking of hexene and heptene occurred by a monomolecular mechanism. Small carbon number olefins were the dominant products, along with some aromatics. But there was no evidence that aromatic was an important product. The primary and secondary products were determined by plotting the OPE(Optimum Performance Envelope) curves.A molecularly explicit model for catalytic cracking of n-heptene on ZSM-5 zeolite was developed. The Boolean relation matrices were used to describe the hydrocarbons and carbenium ions. All the reactions were divided into 14 single events, and every single event reactions can be obtained by changing the Boolean relation matrices. Then the complex physical model was transformed into a mathematical model. In order to reduce the reaction rate coefficients, the model was simplified. At last a complete reaction network was obtained.Studying the chemical reaction and chemistry mechanism in petrochemical process can not only help to know the possible reactions and the reaction dynamics, but also is helpful to catalyst design, choosing the favorable operating conditions as well as developing new catalytic cracking technology.
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