A method for preparing a catalyst system for heterogenous catalysis of an isobutylene polymerization reaction includes the steps of forming an alumina support in which the alumina support has pores formed therein, and reacting BF3/methanol catalyst complex with the alumina support. The ratio of methanol to BF3 in the catalyst complex ranges from 0.5 moles to 2 moles of methanol per mole of BF3. The alumina support is formed so as to have pores each having a diameter of greater than twenty nanometers. The alumina support can be in the form of beads or extrudates having a length significantly greater than a diameter. The extrudate can also have a tri-lobe configuration.