| 摘要 |
Olefins are polymerized and copolymerized in the presence of a catalyst which has been made by depositing a Cr-containing compound, the Cr in which is at least partially present as Cr6+O3 after heating with molecular O2, on to a carrier under substantially anhydrous conditions in the presence of an anhydrous organic liquid which will not generate water during the preparation of the anhydrous catalyst, and subsequently heating the carrier material in the presence of molecular O2. Example 3 describes the polymerization of ethylene containing 3% propylene in cyclohexane which has been charged to a reactor at 125-130 DEG C. and 450 p.s.i.g. and Example 5 describes similar details of a 5/95 propylene/ethylene mixture.ALSO:A polymerization catalyst is made by depositing a Cr-containing compound, the Cr in which is at least partially present as Cr6+O3 after heating in the presence of molecular oxygen, on to a carrier under substantially anhydrous conditions in the presence of an anhydrous organic liquid which will not generate water during the preparation of the anhydrous catalyst, and subsequently heating the carrier material in the presence of molecular oxygen. The carrier may be SiO2, SiO2 gel, SiO2/Al2O3 or Al2O3 p and preferably has a surface area of 200-700 sq.m./gm. Specified organic liquids are benzene, xylene, toluene, naphthalene, cumene, cymene, ethyl benzene, propane, butane, pentane, hexane, carbon tetrachloride, chloroform or tetrahydrofuran. Examples are given. |
