New method to see how catalyst works: useful for high level process control

15 February 2002

PhD thesis defence Fumihiko Shimizu, faculty of Chemical Technology: ‘Liquid Pool Polymerization of Propylene and Ethylene Using a Highly Active Ziegler-Natta Catalyst’

The Ziegler-Natta catalyst is an extremely important catalyst in industry for the production of polyethylene and polypropylene. However, a lot of phenomena related to this catalyst are still unknown. Fumihiko Shimizu demonstrates a new method to ‘see’ how the Ziegler-Natta catalyst works in the reactor. She devised a special calorimeter, which obtains not only kinetic data by calorimetry, but also polymer samples at any interval during polymerization. This means that it is possible to track the change in polymer structure as a function of time. It should be noted that the change in polymer structure is the result of the change in the active site structure. By combining the kinetic data with this information, Shimizu describes how the catalyst works more precisely than before. In other words, she can "see" how the catalyst works in the reactor.
The information obtained can be applied in various ways. For example, the catalyst performance can be improved by knowing how the catalyst actually works. Another example is the process modeling. Based on the precise description of the catalyst behavior, it is possible to build a mathematical model for a process. Such a modeling study is very useful for high level process control in industry.

supervisor: Prof. dr. ir. W.P.M. van Swaaij
second supervisor: Prof. Dr. -Ing. habil. G. Weickert
information: drs. B. Koopmans, telefoon (053) 489 43 66