Spherical Magnesium-Supported Catalyst Particles

7 Catalysts Prepared with Grignard Reagent/TiCl with and without Silica 

Catalysts based on ethylmagnesium chloride in THF and TiCl were prepared in the presence and absence of silica [64]. The silica was a Davison (W. R. Grace) Commercial Grade 952 silica with an average particle size of 45 pm and was dried at 200°C. The silica was used as a template to control the particle size distribution of the catalyst precursor. 

Catalyst Prepared with Silica This catalyst was prepared in two steps. In the first step, ethylmagnesium chloride in THF (2.1 M) was added drop-wise to the silica, which was slurried in hexane and stirred rapidly while xmder reflux conditions. Next, the solvents were removed by distillation to provide a white free-flowing powder. In the second step, the white powder was slurried in heptane containing TiCl and the slurry was refluxed for 2 hr and then allowed to cool to room temperattue. The silica-supported catalyst was isolated by filtration, washed with excess hexane and dried again to obtain a free-flowing powder. 

Catalyst Prepared without Silica This catalyst was prepared by adding 

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