A kind of olefin polymerization catalyst and its preparation method and application

Abstract

The invention relates to the field of olefin polymerization catalysts and discloses a preparation method of an olefin polymerization catalyst. The preparation method comprises the following steps that (1) a magnesium compound, an organic phosphorus compound and an organic epoxy compound are in mutual contact in a solvent to form a homogeneous solution; (2) at the presence of a precipitation promoting agent, the homogeneous solution makes contact with a titanium compound and a mixture is obtained; (3) the mixture makes contact with ester and alcohol and a solid-liquid mixture is obtained; and (4) optionally, the solid-liquid mixture makes contact with an internal electron donor compound and the olefin polymerization catalyst is obtained. The invention further provides the olefin polymerization catalyst prepared by means of the preparation method and an application thereof in an olefin polymerization reaction. By introducing the ester and the alcohol in the preparation process of the olefin polymerization catalyst, the spherical olefin polymerization catalyst with the particle diameter being 25 microns or above can be prepared, so that preferable mobility is guaranteed. In addition, when the olefin polymerization catalyst is used for the olefin polymerization reaction, the condition that polymer bulk density is reduced does not occur.

Description

technical field [0001] The invention relates to the field of olefin polymerization catalysts, in particular to a method for preparing an olefin polymerization catalyst, an olefin polymerization catalyst prepared by the method, and an application of the olefin polymerization catalyst in olefin polymerization reactions. Background technique [0002] The currently disclosed methods for preparing solid titanium catalyst components for olefin polymerization are divided into two categories, one is supported catalysts, that is, active components containing titanium are loaded on a carrier with a certain shape, and the main raw material used for the carrier is generally magnesium chloride. Or silica gel, the shape is mostly spherical, such as the methods disclosed in patents such as US4399054 and EP-B-65700; the other is a granular catalyst, which is to prepare magnesium chloride powder into a uniform solution, and then crystallize and load the active group containing titanium. poin...

AI Technical Summary

Problems solved by technology

Chinese patent 98111780.5 discloses a method for obtaining larger particles by increasing the amount of solvent toluene in the magnesium chloride dissolution system, and mentions that when the particle size is large, non-spherical particles such as rod-shaped, needle-shaped, and jujube-shaped particles are likely to appear, And disclose the method that solves these problems, apply this patent method and can prepare the particle below 25 microns, but when adding toluene again to make particle size larger, the probability of non-spherical particle appears greatly increases, so this method can not be used for the preparation Particles above 25 microns

[0008] In summary, the preparation of granular catalyst components with a particle size above 25 microns by the existing technology is not satisfactory at present, and the production of catalyst components in this particle size range cannot meet the requirements.