New insights in the working principles of Cr/SiO2 Phillips catalysts in the presence and absence of alkyl compounds as co-catalystPhillips-type ethylene polymerization catalysts are responsible for more than one third of all polyethylene sold worldwide. Despite extensive research into the working mechanism of this process, there still is no univocal consensus on the active site and related catalyst activation and polymerization mechanism. Recently, the interaction between tri-ethyl… Show more New insights in the working principles of Cr/SiO2 Phillips catalysts in the presence and absence of alkyl compounds as co-catalystPhillips-type ethylene polymerization catalysts are responsible for more than one third of all polyethylene sold worldwide. Despite extensive research into the working mechanism of this process, there still is no univocal consensus on the active site and related catalyst activation and polymerization mechanism. Recently, the interaction between tri-ethyl aluminium, as a co-catalyst, and Cr/SiO2 Phillips catalyst has been investigated, as well as ethylene polymerization properties of this system. The focus of my research is on investigating metal-alkyl compounds, such as tri-ethyl borane and tri-ethyl aluminum, and investigate their interaction with the Cr/SiO2 Phillips Catalyst. The ultimate goal is to gain new insights into the working state of this catalyst by combining industrial findings with advanced microscopic and spectroscopic techniques. Show less