Mathematical Modeling of Propylene Polymerization with Ziegler-Natta Catalyst and Hydrogen Response Validation

Document Type : Research Article


1 Department of Petroleum and Chemical Engineering, Science and Research Branch, Islamic Azad University, Tehran, I.R. IRAN

2 Department of Chemical and Bimolecular Engineering, Research Associates of Rice University, USA


< p>Hydrogen in spite of having a chain transfer agent role is one of the most important factors which directly affecting on kinetic of propylene polymerization. Hydrogen causes to dramatically increase the percentage of activated sites in proportion to being total potential sites on the catalyst surface. On the other hand, the chain transfer agent role of hydrogen gives rise to changing some vital indices of final product properties. This study has attempted to present a validated mathematical model that able to predicting profile polymerization rate and also calculating some of the vital indices of the final product, properties to be derived from kinetic equations. Furthermore, in this paper, we present a developed model that calculates fraction activated sites catalyst via hydrogen concentration based on dormant site theory and determining the best process condition. The modeling approach is based on the polymer moment balance method, i.e. population balance technique, and validated by experimental works. The main aim of this study is assigned to investigate the behavior change of polymerization rate to hydrogen. The experimental data and model outputs were compared and concluded that the global errors were in the acceptable range.


Main Subjects

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