TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: Preparation of metallocene catalyst solution includes dissolving the metallocene catalyst in the supercritical-like solvent at 30-100degreesC and 25-5000 psia (preferably 100-3500 psia). Removal of supercritical-like solvent includes converting the supercritical-like solvent to gaseous state by adjusting the temperature or pressure of the solvent. The method includes providing a second metallocene catalyst solution comprising a second metallocene catalyst dissolved in a supercritical-like solvent, reacting the support material with the second metallocene catalyst solution, and removing the supercritical-like solvent of the second solution from the second metallocene catalyst and support material. The metallocene catalyst solution and the second metallocene catalyst solution are reacted with the support material simultaneously. In other embodiment, production of supported metallocene catalyst system includes preparing an organic catalyst solution comprising organic catalyst dissolved in a liquid hydrofluorocarbon solvent containing at least65 wt.% fluorine and having a surface tension of at most22 dynes/cm, reacting a support material with the organic catalyst solution, and removing liquid hydrofluorocarbon solvent from the organic catalyst and support material; or preparing a metallocene catalyst solution comprising transition metal metallocene catalyst dissolved in a supercritical-like solvent at -10-200degrees, reacting a support material with the metallocene catalyst solution, and removing the supercritical-like solvent from the metallocene catalyst and support material. Preferred Components: The hafnium metallocene catalyst comprises hafnium (IV) compound, preferably dimethylbis(t-butylcyclopentadienyl) hafnium (IV). It may comprise a co-catalyst, e.g. tri-(n-butyl) ammonium tetrakis (pentafluorophenyl) boron, tris(pentafluorophenyl) borane, alumoxane, and/or methyl alumoxane. The metallocene catalyst may be ferrocene, or zirconium metallocene, e.g. dichlorobis(n-butylcyclopentadienyl) zirconium (IV) and/or dichlorobis(cyclopentadienyl) zirconium (IV). The supercritical-like solvent is a solvent in its supercritical state, or a liquid solvent in subcritical state such as methane, ethane, ethylene, propylene, trifluorochloromethane, difluoromethane, isomer of tetrafluoroethane, pentafluoroethane, isomer of trifluoroethane, isomer of pentafluoropropane, difluorochloromethane, isomer of tetrafluorochloroethane, ammonia, and/or preferably liquid carbon dioxide. The solvent of second solution is a selective solvent for the second metallocene catalyst.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The transition metal is Groups IV-VI transition metal, preferably titanium. The support material is alumina, silica, or silica treated with halogenated organic compound. The support material comprises particles or a single unitary body.