A catalyst composition, a preparation method thereof and an application thereof

Abstract

The present invention relates to a catalyst composition, a preparation method and an application thereof. Specifically, a non-metallocene complex and a metallocene complex are dissolved in an organic medium to obtain a mixed solution of metal complexes, and then the obtained mixed solution of metal complexes is added dropwise to a suspension of an active support under the protection of an inert atmosphere, followed by stirring and reacting, and then separating, washing and drying to obtain the target product. The catalyst of the present invention is particularly suitable for catalyzing the polymerization of ethylene, and the polymer obtained after polymerization has a bimodal molecular weight distribution. At the same time, the polymer particles are uniform and have good fluidity, which can meet the requirements of industrial production.

Description

Technical Field

[0001] The present invention belongs to the technical field of polyolefin catalysts, and relates to a catalyst composition, a preparation method thereof, and an application thereof. Background Art

[0002] Polyethylene is currently the most important general-purpose plastic in the world and is also the polymer material with the largest output and the widest application in synthetic resins. Its main varieties include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, and bimodal polyethylene, etc. Bimodal polyethylene has a different molecular weight distribution from ordinary polyethylene, and its molecular weight distribution curve shows a bimodal distribution characteristic. The low molecular weight part is homopolyethylene with a regular linear structure, high crystallinity, and at the same time a low molecular weight, which is easy to process. The high molecular weight part is copolymerized polyethylene with longer molecular chains and higher branching degrees. Its crystallization ability is weaker than that of the low molecular weight part, and the non-crystalline molecular chains will penetrate through the crystal flakes to form tie molecules, ensuring the long-term mechanical properties of the material. Bimodal polyethylene materials have both good processing properties and excellent mechanical properties, such as high tensile strength, excellent toughness, creep resistance, and environmental stress cracking resistance. The products are widely used in fields such as films, blow molding, and high-performance pipes.

[0003] Due to the excellent properties of bimodal polyethylene, it has attracted much attention in the industrial and academic fields. Currently, the processes for producing bimodal polyethylene mainly include the series multi-reactor method and the single-reactor method. The single-reactor method has the advantages of low equipment investment, simple process operation, convenient start-up and shutdown, and relatively uniform mixing of high- and low-molecular weight products compared with the series multi-reactor method, and is an important research direction for producing bimodal polyethylene. Synthesizing bimodal polyethylene in a single reactor mainly involves developing a catalyst system containing two different metal active centers and using the differential polymerization behavior of the active components to obtain a polyethylene resin with a bimodal molecular weight distribution.

[0004] Nova Corporation has developed a highly active phosphinimine titanium-based catalyst system. In patent EP3612571 B, a solution process using a Sclalrtech dual reactor is reported. By means of high-intensity mixing and short residence time, the performance of bimodal polyethylene is improved. The polymerization is carried out under high-temperature homogeneous conditions, and the production conditions are relatively harsh.

[0005] Total Corporation reported in patent US11274171 B the use of a bridged cyclopentadienyl fluorenyl zirconium metal-non-bridged cyclopentadienyl hafnium metal composite supported catalyst. Since the zirconium catalyst and the hafnium catalyst have different sensitivities to hydrogen and comonomers, hydrogen is used to adjust the molecular weight and molecular weight distribution, and comonomers are used to adjust the content and distribution of short branches to produce bimodal polyethylene. However, there is a strong interaction between the metallocene atoms, and the overall activity of the catalyst after loading is relatively low.

[0006] There is no strong interaction between the early transition metallocene and the late transition non-metallocene atoms, and the two catalysts have good compatibility. Therefore, the non-metallocene-metallocene composite catalyst is a research hotspot for bimodal polyethylene catalysts. Univation reported in the patent US10865259 B that the Prodigy bimodal catalyst can produce bimodal polyethylene in an industrial single reactor. Based on the composite catalyst technology, the large-scale production of bimodal polyethylene can be achieved through a single gas-phase polymerization reactor, and the resin has good physical properties and processing properties. However, the preparation route of the active center is relatively complex, and the expensive methylaluminoxane needs to be used as a cocatalyst for the catalyst loading, resulting in high catalyst costs.

[0007] As disclosed in the Chinese patent application CN115894746A, a supported catalyst composition, its preparation method and application are provided. The preparation method of the supported catalyst composition is as follows: (1) After the silica gel carrier is heat-activated and placed in a sealed container, an organic medium is added, an alkyl metal is added under an inert atmosphere, and the reaction is stirred. Then a bulky heteroatom aryl polyfunctional compound is added, and the reaction continues to obtain a modified silica gel carrier; (2) The obtained modified silica gel carrier is placed under an inert atmosphere, and an organoaluminum compound is added dropwise for reaction to obtain an active silica gel carrier; (3) The metallocene complex is dissolved in an organic medium, and then the obtained metallocene complex solution is added dropwise to the active silica gel carrier under an inert atmosphere, and the reaction is stirred to obtain the target product. This patent requires the use of precious raw material aluminoxane in the preparation process, and the catalyst can be used to prepare single-peak polymers, but cannot be used to prepare bimodal polymers.

[0008] ExxonMobil reported in the patent CN108137747 that a non-metallocene pyridyl diamino hafnium complex and a metallocene composite catalyst are used as dual active centers, and a supported catalyst formed with silica gel and methylaluminoxane as the carrier and cocatalyst is used to produce bimodal distribution polyethylene. The molecular weight distribution of the resin is relatively wide, but the overall activity of the catalyst is low.

[0009] In summary, although many breakthroughs have been made in the research of bimodal polyethylene catalysts, it is still difficult to overcome the disadvantages such as high catalyst cost, mutual inhibition of active centers, and supported deactivation. There are still bottlenecks in technologies such as developing non-metallocene-metallocene composite active centers, researching new high-efficiency carriers and loading methods, reducing catalyst costs, and improving catalytic efficiency, which need further improvement and breakthrough. Summary of the Invention

[0010] The purpose of the present invention is to provide a catalyst composition, its preparation method and application, which are particularly suitable for catalyzing ethylene polymerization, and the polymer obtained after polymerization has a bimodal molecular weight distribution. At the same time, the polymer particles are uniform and have good fluidity, which can meet the requirements of industrial production.

[0011] The object of the present invention can be achieved by the following technical solutions:

[0012] One of the technical solutions of the present invention provides a preparation method of a catalyst composition, wherein a non-metallocene complex and a metallocene complex are dissolved in an organic medium to obtain a mixed metal complex solution, and then the obtained mixed metal complex solution is dropped into an active support (preferably in the form of a suspension, such as a toluene suspension, etc.) under the protection of an inert atmosphere, stirred and reacted, and then separated, washed and dried to obtain the target product.

[0013] Further, the non-metallocene complex is selected from phenoxyimine titanium group metal complexes having the structures shown in formula (I) or formula (II):

[0014]

[0015] Among them, X1 is one of C, Si and Ge;

[0016] X2 and X3 are the same or different, and are linear alkyl groups with 1 to 10 carbon atoms, halogen atoms, nitrogen-containing groups, halogen-containing groups, oxygen-containing groups, phosphorus-containing groups, boron-containing compounds or heteroatom groups;

[0017] R1 to R 12 are each independently hydrogen, an alkyl group with 1 to 20 carbon atoms, a halogen, a halogen-containing group, an oxygen-containing group, a phosphorus-containing group, a boron-containing compound, a heterocyclic group, an aromatic group or an alicyclic group;

[0018] R 13 、R 14 and R 15 are each independently one of hydrogen, methyl, ethyl, isopropyl or tert-butyl.

[0019] Further, the metallocene complex is selected from one or more of bis(cyclopentadienyl)zirconium dichloride, bis(cyclopentadienyl)titanium dichloride, cyclopentadienyltitanium trichloride, bis(tert-butylcyclopentadienyl)titanium dichloride, bis(n-butylcyclopentadienyl)zirconium dichloride, bis(n-butylcyclopentadienyl)dimethylzirconium, bis(pentamethylcyclopentadienyl)zirconium dichloride, bis(pentamethylcyclopentadienyl)dimethylzirconium, bis(tetrahydro-1-indenyl)zirconium dichloride, dimethylsilylbis(tetrahydro-1-indenyl)zirconium dichloride.

[0020] Further, the mass ratio of the non-metallocene complex to the metallocene complex is 1:1 to 10:1; the total mass ratio of the non-metallocene complex and the metallocene complex to the active support is 1:1 to 10,000.

[0021] Further, the reaction temperature is 0 to 100 °C and the time is 1 to 48 h.

[0022] Further, the active carrier is an active silica carrier or an active magnesium chloride carrier. Preferably, the preparation process of the active silica carrier is specifically as follows:

[0023] The silica carrier is mixed with a fluoride for surface modification by reaction, then subjected to thermal activation treatment by high-temperature roasting, and then an organoaluminum compound is added and the reaction is continued to obtain the active silica carrier.

[0024] Furthermore, in the preparation process of the active silica carrier: the mass ratio of the silica carrier, the fluoride and the organoaluminum compound is (1-10):(0.05-0.5):(0.01-0.2).

[0025] Furthermore, the fluoride is selected from one or more of hydrofluoric acid, ammonium fluoride, ammonium bifluoride, ammonium fluoroborate, fluoroboric acid, fluorosilicic acid, magnesium fluoride, aluminum fluoride, and hexafluorophosphoric acid; the organoaluminum compound is selected from one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, and trioctylaluminum.

[0026] Furthermore, the thermal activation treatment process is specifically as follows: the silica carrier is treated at 100-800 °C for 1-36 h under a protective atmosphere or reduced pressure conditions.

[0027] Furthermore, the temperatures of the mixing reaction and the continued reaction are independently 0-120 °C, and the times are independently 1-24 h.

[0028] Furthermore, the particle size of the silica carrier is 1.0-80 μm, the pore volume is 0.5-3.0 mL / g, the pore diameter is 10-30 nm, the specific surface area is 150-850 m 2 / g, and the alumina content in the silica is 0-50 wt%.

[0029] Preferably, the preparation process of the active magnesium chloride carrier is specifically as follows:

[0030] The magnesium chloride alcoholate is placed in an organic medium, and an organoaluminum compound is added dropwise under an inert atmosphere to obtain a slurry, and the reaction is stirred, and then separated, washed, and dried to obtain the active magnesium chloride carrier.

[0031] Furthermore, in the preparation process of the active magnesium chloride carrier:

[0032] The magnesium chloride alcoholate is a magnesium chloride alcoholate formed by magnesium chloride and a C1-C10 linear or branched alkyl monohydric alcohol or polyhydric alcohol in a molar ratio of 1:1-1:5;

[0033] Furthermore, the organoaluminum compound is selected from one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, and trioctylaluminum.

[0034] Furthermore, the addition ratio of the magnesium chloride alcohol complex to the organoaluminum compound is (1 - 5) g : (5 - 10) mL.

[0035] Furthermore, the temperature of the stirring reaction is 0 - 100 °C, and the time is 1 - 24 h. Additionally, the stirring speed during the reaction is 100 - 3000 rpm, and the particle size of the active magnesium chloride support is 1.0 - 100 μm.

[0036] The second technical solution of the present invention provides a catalyst composition prepared by using the preparation method described in any one of the above.

[0037] The third technical solution of the present invention provides an application of the catalyst composition. This catalyst composition is used in the ethylene polymerization process, such as for ethylene homopolymerization and copolymerization, to obtain a polymer with a bimodal molecular weight distribution.

[0038] Further, when the catalyst composition is used for ethylene homopolymerization and copolymerization, the catalyst composition is used as the main catalyst, and an alkylaluminum compound is used as the cocatalyst to carry out gas-phase polymerization or slurry polymerization reaction of the organic polymerization monomer in an organic medium. The catalyst activity reaches 10,000 g of polyethylene / g of catalyst. The molecular weight of the polymer obtained after polymerization is 10,000 - 1,000,000, and the molecular weight distribution is bimodal, with a molecular weight distribution of 5.0 - 50. At the same time, the polymer particles are uniform and have good fluidity, meeting the requirements of industrial production.

[0039] Furthermore, the organic polymerization monomer is ethylene, or ethylene and an α-olefin. Among them, the α-olefin can specifically be propylene, 1-butene, 1-hexene, 1-octene, or 1-decene. Description of the Drawings

[0040] Figure 1 It is the molecular weight distribution diagram of the polymer obtained by catalyzing ethylene polymerization with the catalyst composition prepared in Example 8. Detailed Embodiments

[0041] The present invention will be described in detail below with reference to specific embodiments. These embodiments are implemented on the premise of the technical solutions of the present invention, and detailed implementation methods and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments.

[0042] In the following examples, the silica gel is a commercially available amorphous silica gel with the trade names Sylopol 948, Sylopol 952, Sylopol 955 (Grace Davison, USA), ES-757, ES-747 (INEOS Group); the silica-alumina is a commercially available product with the trade names Siral 10, Siral 20, Siral 28, Siral 40 (Sasol, Germany);

[0043] The phenoxyimine titanium group complexes used include but are not limited to the following chemical structural formulas:

[0044]

[0045] For the remaining raw materials or processing techniques without special instructions, it means that they are all conventional commercially available raw materials or conventional processing techniques in this field.

[0046] Example 1:

[0047] Pretreatment of the active silica gel carrier S1

[0048] Weigh 0.5 g of ammonium bifluoride and dissolve it in 20 mL of water. The resulting colorless and clear liquid is added dropwise to 10 g of silica gel (Sylopol 955), and then placed in an oven at 100 °C for drying. After the water has evaporated completely, the mixture is calcined in a nitrogen atmosphere at 600 °C for 3 hours. After cooling, 0.2 g of triethylaluminum is added and the reaction continues to obtain the active silica gel carrier S1.

[0049] Examples 2 - 4:

[0050] Compared with Example 1, most of them are the same, except that triethylaluminum is replaced with the same mass of trimethylaluminum, triisobutylaluminum, and trioctylaluminum to obtain the active silica gel carriers S2, S3, and S4.

[0051] Example 5:

[0052] Preparation of the active magnesium chloride carrier M1

[0053] The magnesium chloride solid powder is dehydrated at 200 °C for 3 hours. Add 2.0 g of the heat-treated magnesium chloride powder, 10 g of isooctanol, and 40 mL of n-decane to a 200 mL reaction flask, stir at 130 °C for 2 hours, and then cool naturally. At 0 °C and in a nitrogen atmosphere, 5 mL of triethylaluminum is added dropwise to the reaction flask, stirred at room temperature for 2 hours, filtered, washed 3 times with n-hexane, and vacuum dried to obtain the flowing powder active magnesium chloride carrier M1.

[0054] Example 6:

[0055] Compared with Example 2, most of them are the same, except that the process parameter conditions are adjusted as follows: the ratio of the addition amounts of magnesium chloride alcoholate and organoaluminum compound is 1 g: 5 mL; the temperature of the stirring reaction is 0 °C and the time is 24 hours. The active magnesium chloride support M2 is obtained.

[0056] Example 7:

[0057] Compared with Example 2, most of them are the same, except that the process parameter conditions are adjusted as follows: the ratio of the addition amounts of magnesium chloride alcoholate and organoaluminum compound is 5 g: 10 mL; the temperature of the stirring reaction is 100 °C and the time is 1 hour. The active magnesium chloride support M3 is obtained.

[0058] Example 8:

[0059] Preparation of catalyst composition C1-S1

[0060] Under argon protection, 0.5 g of active silica support S1 was added to a 100 mL reaction flask. 10.0 mg of phenoxyimine zirconium complex Zr1 and 10.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene, and then added to the reaction flask. The mixture was stirred at room temperature for 1 hour. After filtration, it was washed twice with toluene and dried under vacuum to obtain a catalyst powder.

[0061] Example 9:

[0062] Preparation of catalyst composition C2-S1

[0063] Under argon protection, 5.0 g of active silica support S1 was added to a 100 mL reaction flask. 10.0 mg of phenoxyimine zirconium complex Zr2 and 10.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene, and then added to the reaction flask. The mixture was stirred at room temperature for 1 hour. After filtration, it was washed twice with toluene and dried under vacuum to obtain a catalyst powder.

[0064] Example 10:

[0065] Preparation of catalyst composition C3-S1

[0066] Under argon protection, 50.0 g of active silica support S1 was added to a 100 mL reaction flask. 10.0 mg of phenoxyimine zirconium complex Zr3 and 10.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene, and then added to the reaction flask. The mixture was stirred at room temperature for 1 hour. After filtration, it was washed twice with toluene and dried under vacuum to obtain a catalyst powder.

[0067] Example 11:

[0068] Preparation of catalyst composition C4-M1

[0069] Under argon protection, 0.5 g of the active magnesium chloride support M1 was suspended in 5 mL of toluene in a 100 mL reaction flask. 10.0 mg of the phenoxyimine zirconium complex Zr4 and 10.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene. The mixed solution was added to the toluene suspension of the active magnesium chloride support M1, and the reaction was stirred at room temperature for 1 hour. Filtration was carried out, followed by washing twice with toluene, and then drying under vacuum to obtain the catalyst powder.

[0070] Example 12:

[0071] Preparation of catalyst composition C5-M1

[0072] Under argon protection, 5.0 g of the active magnesium chloride support M1 was suspended in 5 mL of toluene in a 100 mL reaction flask. 10.0 mg of the phenoxyimine zirconium complex Zr5 and 10.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene. The mixed solution was added to the toluene suspension of the active magnesium chloride support M1, and the reaction was stirred at room temperature for 1 hour. Filtration was carried out, followed by washing twice with toluene, and then drying under vacuum to obtain the catalyst powder.

[0073] Example 13:

[0074] Preparation of catalyst composition C6-M1

[0075] Under argon protection, 50.0 g of the active magnesium chloride support M1 was suspended in 5 mL of toluene in a 100 mL reaction flask. 10.0 mg of the phenoxyimine zirconium complex Zr6 and 10.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene. The mixed solution was added to the toluene suspension of the active magnesium chloride support M1, and the reaction was stirred at room temperature for 1 hour. Filtration was carried out, followed by washing twice with toluene, and then drying under vacuum to obtain the catalyst powder.

[0076] Example 14:

[0077] Preparation of catalyst composition C7-M1

[0078] Under argon protection, 0.5 g of the active magnesium chloride support M1 was suspended in 5 mL of toluene in a 100 mL reaction flask. 10.0 mg of the phenoxyimine titanium complex Ti1 and 5.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene. The mixed solution was added to the toluene suspension of the active magnesium chloride support M1, and the reaction was stirred at room temperature for 1 hour. Filtration was carried out, followed by washing twice with toluene, and then drying under vacuum to obtain the catalyst powder.

[0079] Example 15:

[0080] Preparation of catalyst composition C8-M1

[0081] Under argon protection, 5.0 g of the active magnesium chloride support M1 was suspended in 5 mL of toluene in a 100 mL reaction flask. 10.0 mg of the phenoxyimine titanium complex Ti2 and 2.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene. The mixed solution was added to the toluene suspension of the active magnesium chloride support M1, and the reaction was stirred at room temperature for 1 hour. After filtration, it was washed twice with toluene and dried under vacuum to obtain the catalyst powder.

[0082] Example 16:

[0083] Preparation of the catalyst composition C9-M1

[0084] Under argon protection, 50.0 g of the active magnesium chloride support M1 was suspended in 5 mL of toluene in a 100 mL reaction flask. 10.0 mg of the phenoxyimine titanium complex Ti3 and 10.0 mg of bis(cyclopentadienyl)zirconium dichloride were weighed and dissolved in 5.0 mL of toluene. The mixed solution was added to the toluene suspension of the active magnesium chloride support M1, and the reaction was stirred at room temperature for 1 hour. After filtration, it was washed twice with toluene and dried under vacuum to obtain the catalyst powder.

[0085] Examples 17 - 20:

[0086] Compared with Example 8, most of them are the same, except that the metallocene complex bis(cyclopentadienyl)zirconium dichloride was replaced with an equal mass of bis(cyclopentadienyl)titanium dichloride, bis(n-butylcyclopentadienyl)zirconium dichloride, bis(pentamethylcyclopentadienyl)zirconium dichloride, and bis(tetrahydro-1-indenyl)zirconium dichloride, respectively.

[0087] Examples 21 - 23:

[0088] Compared with Example 8, most of them are the same, except that S1 was replaced with an equal mass of S2, S3, and S4.

[0089] Examples 24 - 25:

[0090] Compared with Example 14, most of them are the same, except that M1 was replaced with an equal mass of M2 and M3.

[0091] Example 26:

[0092] Compared with Example 14, most of them are the same, except that its process parameter conditions were adjusted to: the mass ratio of the non-metallocene complex to the metallocene complex is 1:1; the total mass of the non-metallocene complex and the metallocene complex to the mass of the active support is 1:1; the reaction temperature is 0 °C and the time is 48 h.

[0093] Example 27:

[0094] Compared with Example 14, most of them are the same, except that the addition amounts of each raw material are adjusted as follows: the mass ratio of the non-metallocene complex to the metallocene complex is 10:1; the total mass ratio of the non-metallocene complex and the metallocene complex to the mass of the active support is 1:10000; the reaction temperature is 100 °C and the time is 1 h.

[0095] Example 28:

[0096] Compared with Example 19, most of them are the same, except that the non-metallocene complex is replaced with an equal mass of metallocene complex.

[0097] Example 29:

[0098] Compared with Example 19, most of them are the same, except that the metallocene complex is replaced with an equal mass of non-metallocene complex.

[0099] Examples 30 - 34

[0100] Compared with Example 19, most of them are the same, except that the process parameter conditions are adjusted as follows: the mass ratio of the non-metallocene complex to the metallocene complex is 2:1, 4:1, 6:1, 8:1, 10:1.

[0101] Example 35:

[0102] The catalyst composition is used for preparing polyethylene

[0103] The ethylene polymerization reactor is a 2L stainless steel reactor equipped with a heat transfer oil circulation temperature control. First, the reactor is vacuum-treated at 120 °C for 1 hour, cooled to 80 °C, and filled with nitrogen to atmospheric pressure. Under a nitrogen atmosphere, 1.0 L of solvent oil, 1-hexene, and a certain amount of catalyst composition are added. Then, ethylene is replaced three times, a small amount of hydrogen is added, and the intake valve is adjusted to keep the ethylene pressure constant at 1.0 MPa. The polymerization reaction is carried out at 80 °C. After the reaction, the polymer is collected, dried to a constant weight, weighed, the catalyst activity is calculated, and the molecular weight and molecular weight distribution of the polymer are tested. The results are listed in Table 1.

[0104] Table 1 Results of Catalytic Ethylene Polymerization

[0105]

[0106]

[0107] In addition, in combination with Figure 1 It can be seen that the catalyst composition prepared in Example 8 contains two metal catalytic active centers. During the above catalytic ethylene polymerization process, it exhibits different catalytic characteristics, has different chain growth rates and chain termination rates, that is, a polymer with a bimodal distribution is obtained.

[0108] The above description of the embodiments is provided to enable those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and all improvements and modifications made by those skilled in the art without departing from the scope of the present invention as disclosed should be within the protection scope of the present invention.

Claims

1. A method for preparing a catalyst composition, characterized in that, Dissolve the non-metallocene complex and the metallocene complex in an organic medium to obtain a mixed solution of metal complexes. Then, under the protection of an inert atmosphere, dropwise add the obtained mixed solution of metal complexes to a suspension of an active support, stir and react, and then separate, wash, and dry to obtain the target product; The non-metallocene complex is selected from any one of the following chemical structural formulas: 、 、 ； The metallocene complex is selected from one or more of bis(cyclopentadienyl)zirconium dichloride, bis(cyclopentadienyl)titanium dichloride, cyclopentadienyltitanium trichloride, bis(tert-butylcyclopentadienyl)titanium dichloride, bis(n-butylcyclopentadienyl)zirconium dichloride, bis(n-butylcyclopentadienyl)dimethylzirconium, bis(pentamethylcyclopentadienyl)zirconium dichloride, bis(pentamethylcyclopentadienyl)dimethylzirconium, bis(tetrahydro-1-indenyl)zirconium dichloride, dimethylsilylbis(tetrahydro-1-indenyl)zirconium dichloride; The active support is an active silica support or an active magnesium chloride support, wherein The preparation process of the active silica support is specifically as follows: Mix and react the silica support with a fluoride for surface modification, then perform thermal activation treatment by high-temperature roasting, and then add an organoaluminum compound triethylaluminum or trimethylaluminum and continue the reaction to obtain the active silica support; The preparation process of the active magnesium chloride support is specifically as follows: Place the magnesium chloride alcoholate in an organic medium, and dropwise add the organoaluminum compound triethylaluminum under an inert atmosphere to obtain a slurry, stir and react, and then separate, wash, and dry to obtain the active magnesium chloride support.

2. The preparation method of a catalyst composition according to claim 1, characterized in that, The mass ratio of the non-metallocene complex to the metallocene complex is 1:1 to 10:1; the total mass ratio of the non-metallocene complex and the metallocene complex to the active support is 1:1 to 10,000.

3. The preparation method of a catalyst composition according to claim 1, characterized in that, After the mixed solution of metal complexes is dropwise added to the suspension of the active support, the temperature of the stirring reaction is 0 to 100 °C, and the time is 1 to 48 h.

4. The preparation method of a catalyst composition according to claim 1, characterized in that, During the preparation process of the active silica support: The mass ratio of the silica support, the fluoride, and the organoaluminum compound is (1 to 10):(0.05 to 0.5):(0.01 to 0.2); The fluoride is selected from one or more of hydrofluoric acid, ammonium fluoride, ammonium bifluoride, ammonium fluoroborate, fluoroboric acid, fluorosilicic acid, magnesium fluoride, aluminum fluoride, hexafluorophosphoric acid; The thermal activation treatment process is specifically as follows: Treat the silica support at 100 to 800 °C under a protective atmosphere or reduced pressure for 1 to 36 h; The temperatures of the mixing reaction and the continued reaction are independently 0 to 120 °C, and the times are independently 1 to 24 h.

5. The preparation method of a catalyst composition according to claim 1, characterized in that, During the preparation process of the active magnesium chloride support: The magnesium chloride alcoholate is a magnesium chloride alcoholate formed by magnesium chloride and a C1-C10 linear or branched alkyl monohydric alcohol or polyhydric alcohol in a molar ratio of 1:1 to 1:5; The organoaluminum compound is selected from one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum; The addition ratio of the magnesium chloride alcoholate to the organoaluminum compound is (1 to 5) g:(5 to 10) mL; The temperature of the stirring reaction is 0 to 100 °C, and the time is 1 to 24 h.

6. A catalyst composition prepared by the preparation method according to any one of claims 1-5.

7. Use of a catalyst composition according to claim 6, characterized in that, This catalyst composition is used in the ethylene polymerization process.

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