| 摘要 |
<p>Catalyst support containing at least two components chosen among silica, alumina and aluminium phosphate, with a specific surface of 100 to 800 m2/g, a crystallization temperature higher or equal to 700 °C, a pore volume of 1.5 to 4 cm3/g, and the relationship between the specific surface (SS) and pore volume (PV) being: SS < (VP x 564 - 358). Process for making such a support, comprising mixing an alcohol, water and a silicon alcoholate and an acid in such conditions that the gelification or precipitation of the silica is avoided, adding an acid solution of an aluminium compound and/or a solution of a phosphate ion source, adding a gelling agent, collecting a gel which is washed with water and then with an organic liquid, drying thereafter the gel until a powder is formed, this powder being then calcined. Olefin polymerization in the presence of a chromium-containing catalyst on the afore-mentioned support.</p> |
