Catalyst component for ethylene polymerization and catalyst thereof

Abstract

The invention provides a catalyst component for ethylene polymerization, which is prepared by a method comprising the following steps of: (1) reacting an alkoxy titanium compound (a) with a magnesium compound (b) to form a solution; (2) adding a porous inorganic oxide (d) and halogenated alkyl aluminum (e) to the solution prepared in the step (1) to separate out sediment; and (3) reacting a liquid titanium compound (h) with the sediment obtained in the step (2) to obtain a titanium-included solid catalyst component. The halogenated alkyl aluminum (e) can be one or more than one of organic aluminum compounds with the general formula of AlRnX3-n, wherein R represents alkyl, aralkyl and aryl with 1-20 hydrogen or carbon atoms, X represents halogen, and n represents an integer which is not less than 0 and not more than 3. The preparation method of the catalyst is simple and has low cost; and when applied to ethylene polymerization, the catalyst has higher activity, and the obtained ethylene polymers have centralized particle size distribution and less content of fine powder.

Description

technical field [0001] The present invention relates to a catalyst component and catalyst for ethylene polymerization. More specifically, it relates to a catalyst component prepared by reacting alkoxytitanium, magnesium compound, haloalkylaluminum, porous oxide carrier and liquid titanium compound and the catalyst thereof. technical background [0002] As we all know, in the current industrialized process for preparing ethylene polymers, if the catalyst used has high catalytic activity, not only can the output be increased, but also the problem of catalyst residue in the unit polymer can be reduced, and the halogen in the residual catalyst may Causes mold rusting problems in polymer post-processing molding processes. At the same time, in the existing various polymerization processes, the prepared ethylene polymers are required to have good fluidity, less fine powder and excellent particle size distribution, which can reduce the troubles encountered in the post-processing of...

AI Technical Summary

Problems solved by technology

The catalyst is very suitable for the condensation technology of the gas-phase fluidized bed, and can prepare high-quality LLDPE resin, but the preparation process of the catalyst needs to add a haloalkane with a special structure as a modifier, which increases the cost of the catalyst

[0006] To sum up, there are two levels of problems in the prior art. The first level is that alkylaluminum halides are generally used as precipitation aids in the solution of magnesium chloride and alkoxytitanium and then prepolymerized. The preparation process is complicated and the cycle is long. ; The second level is that although there is a technology of using silica gel in the catalyst composed of magnesium compound, tetrahydrofuran and titanium halide, it is necessary to add a halide with a special structure as a modifier, which increases the cost of the catalyst

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