CN1098867C - Slurry process total density polyvinyl high-efficiency catalyst - Google Patents

Abstract

The present invention relates to a high efficiency solid catalyst for producing theoretical density polyethylene by slurry polymerization. Commercial magnesium powder is used as initial raw material to prepare nascent state magnesium halide, and then the magnesium halide reacts with organic alcohol and alkylaluminium in sequence to obtain solid suspension. The obtained solid suspension reacts with transition metal halide to obtain the main component of the catalyst in the presence of electron donors and alkylaluminium, and the main component of the catalyst and an organic metal compound as a catalyst promoter together form the high efficiency solid catalyst. The catalyst has the advantages of simple preparing operation, high polymerization activity, sensitive hydrogen regulation, strong copolymerization capability, stable polymerization reaction, favorable particle shape of a polymerization product, etc.

Description

High-efficiency catalyst for slurry-process full-density polyethylene

The invention relates to a high-efficiency solid catalyst suitable for producing full-density polyethylene by low-pressure slurry method polymerization and a method for preparing the catalyst.

Since the successful development of high-efficiency polyethylene catalysts in the 1970s, the world's polyethylene industry has undergone tremendous changes. Over the past 20 years, the leading polyethylene catalyst research has made great progress and formed three major systems: chromium-based high-efficiency catalysts, Ziegler-Natta-type high-efficiency catalysts and metallocene-based high-efficiency catalysts. Among them, Mg-Ti high-efficiency catalysts occupy an important position in the field of polyethylene catalysts because of their excellent performance. Its preparation method has also developed from the co-grinding method, suspension impregnation method, etc. to the current advanced chemical reaction method. The catalyst mentioned in the present invention belongs to Mg-Ti series high-efficiency catalyst prepared by chemical reaction method, and it is applied to slurry polymerization to produce full-density polyethylene. Many patents have been published regarding the various catalysts mentioned above, but there are differences between different patents of different companies, and each has its own advantages and disadvantages.

For example, in the Chinese patent (CN1085569A) applied for by Japan, anhydrous magnesium chloride is reacted with organic alcohol compounds such as 2-ethylhexanol to finally form a uniform solution, then add organic aluminum compounds to precipitate, and then use a large amount of tetrachloride impregnated with titanium oxide to obtain a catalyst. The catalyst has high catalytic activity, simple and easy operation steps, and the obtained product has uniform particle size and high bulk density. However, in the preparation process of the catalyst, the dissolution reaction of magnesium compounds requires a high temperature of 120°C to 140°C, and a large amount of higher alkanes such as decane are used as solvents, which is not only costly, but also has the problem of solvent recovery. In the process of loading the transition metal component titanium, the use of titanium tetrachloride much larger than the loading amount is used for impregnation, causing corrosion problems for equipment.

In the Chinese patent (CN1092093A), magnesium chloride is dissolved in a mixture of organic phosphate and alcohols to form a uniform solution, which is added to the titanium compound in the presence of an organic carboxylic acid anhydride as a precipitation aid, and the catalyst component containing titanium is precipitated by reaction. . The catalyst prepared by the method has high activity, excellent polymerization product performance, very little solvent usage, and improved production capacity. However, in the catalyst preparation process, the temperature for the mixed reaction of the magnesium compound solution and the titanium tetrachloride solution requires -5°C to 10°C, and the operating conditions are relatively harsh, which is not convenient for industrial production and application.

The purpose of the present invention is to provide a novel high-efficiency catalyst for the production of full-density polyethylene by slurry method polymerization. The catalyst uses commercially available magnesium powder as a starting material to obtain a new ecological magnesium halide, which is then successively mixed with organic alcohols React with alkylaluminum, react the obtained solid suspension with transition metal halide in the presence of electron donor and alkylaluminum, and finally prepare the catalyst main component; the catalyst main component and the cocatalyst organometallic The compounds together constitute the high-efficiency polyethylene catalyst of the present invention. The catalyst is easy to prepare and operate, and has the characteristics of high polymerization activity, sensitivity to hydrogen adjustment, strong copolymerization ability, stable polymerization reaction, good shape of polymer particles and the like.

In order to achieve this purpose, the high-efficiency polyethylene catalyst of the present invention is prepared by the following method. The catalyst mentioned in the present invention consists of two parts: the catalyst main body component and the co-catalyst. The catalyst main component is mainly prepared in the following steps:

(1) Preparation of new ecological magnesium halide:

Under the protection of nitrogen, commercially available magnesium powder reacts with haloalkane (RX) in a hydrocarbon solvent. The addition of haloalkane can be one-time addition or slow dropwise addition. After adding, the reaction is continued for 0.5 to 10 hours, preferably 1 to 10 hours. 8 hours. The temperature of the entire reaction is controlled at 10°C-100°C, preferably 20°C-80°C, and finally a new ecological magnesium halide is formed; the reaction can also be carried out in the presence of an electron donor. The resulting new eco-magnesium halide has uniform particle size and spherical shape. The structural formula of the new ecological magnesium halide is (RMgX) _p (MgX ₂ ) _q (ED) _t , wherein, p: q: t = (0-1.0): 1.0: (0-2.0) (molar ratio), preferably It is (0.05～0.8): 1.0: (0～1.0); R is an alkyl group containing 3 to 12 carbon atoms; X is a halogen, preferably chlorine; the electron donor ED contains at least one oxygen, sulfur , nitrogen, silicon, and phosphorus atom organic compounds, which can be aliphatic or aromatic ethers, esters, amines, alcohols, etc. containing 3 to 8 carbon atoms, such as diethyl ether, tetrahydrofuran, ethyl acetate, ethyl benzoate, Tributyl phosphate, isobutanol, N,N-dimethylformamide, etc. Hydrocarbon solvents are aliphatic hydrocarbons, alicyclic hydrocarbons and aromatic hydrocarbons, such as n-pentane, isopentane, cyclopentane, cyclohexane, benzene, etc., preferably aliphatic hydrocarbons containing 5 to 10 carbon atoms. hydrocarbons. The halogenated alkanes (RX) can be chloropropane, chlorobutane, chloroisobutane, chloroisopentane, etc.

(2) Reprocessing of new ecological magnesium halide:

Under the protection of nitrogen, add organic alcohol compound (R'OH) to the new ecological magnesium halide at 10°C-100°C, preferably 20°C-80°C, and stir to react. The addition method of the organic alcohols can be one-time addition or slow dropwise addition, and the reaction is continued for 0.5-8 hours after addition, preferably 1-6 hours. A viscous brown-black suspension was obtained after the reaction. Organic alcohols (R'OH) are aliphatic alcohols containing 3 to 12 carbon atoms, such as methanol, ethanol, 2-methylpentanol, 2-ethylbutanol, 2-ethylhexanol, and the like. The amount of the added organic alcohols is R'OH/Mg=0.2～6 (molar ratio), the best is 0.5～6.0 (molar ratio).

Then, add alkylaluminum to the above suspension, keep the reaction temperature at 20°C-100°C, preferably 30°C-90°C, the addition method can be one-time addition or slow dropwise addition, and continue stirring for 0.5-8 hours after adding. hours, preferably 1 to 6 hours. As the alkylaluminum was added and the reaction proceeded, the viscous, swollen suspension gradually became thinner, eventually forming a dark gray solid suspension with excellent particle morphology. The obtained dark gray solid is a complex carrier composed of magnesium, aluminum, halogen and alkoxy groups. The aluminum alkyl used in the reaction can be triethylaluminum, triisopropylaluminum, triisobutylaluminum, trin-octylaluminum, tris(2-ethyl)hexylaluminum, diethylaluminum chloride, dichloroaluminum Monoethylaluminum, diisopropylaluminum chloride, ethylaluminum sesquichloride, butylaluminum sesquichloride, and the like. The usage amount is controlled to be R'OH/Al=0.2～7 (molar ratio), preferably 0.5～5 (molar ratio).

(3) Preparation of main component of titanium-containing catalyst:

This is a crucial step in the entire catalyst preparation. Under the protection of nitrogen, add the titanium-containing halide to the complex carrier suspension prepared above in the presence of the electron donor and the alkylaluminum, and the addition method of the titanium-containing halide can be one-time addition or slow dropwise addition, Continue to react for 1 to 10 hours after adding, preferably 2 to 8 hours; control the reaction temperature at 20°C to 90°C, preferably 30°C to 60°C; The following molar ratio is followed: ED:Al:Ti:Mg=(0.5-3.0):(0.5-5.0):1:(2.0-10.0). Stirring reaction finally produces brown black catalyst main component suspension. The molar composition ratio of the main components of the high-efficiency polyethylene catalyst prepared according to the invention is as follows: Ti ³⁺ : Ti ^total : Mg: Cl = (0.7-1.0): 1.0: (2.0-10): (4.0-25).

The electron donor (ED) is an organic compound containing at least one oxygen, sulfur, nitrogen, silicon, phosphorus atom, which can be an aliphatic or aromatic ether, ester, amine, alcohol, etc. containing 3 to 8 carbon atoms, such as Diethyl ether, tetrahydrofuran, ethyl acetate, ethyl benzoate, tributyl phosphate, isobutanol, N,N-dimethylformamide, etc. The above electron donors can be used alone or in combination.

Aluminum alkyls are triethylaluminum, triisopropylaluminum, triisobutylaluminum, tri-n-octylaluminum, tris(2-ethyl)hexylaluminum, monochlorodiethylaluminum, dichloromonoethylaluminum , diisopropyl aluminum chloride, ethyl aluminum sesquichloride, butyl aluminum sesquichloride, etc.

Titanium-containing halides are compounds conforming to the general formula Ti(OR") _m Cl _4-m , where R" is an alkyl group containing 3-4 carbon atoms, and m=0-4. Such as titanium tetrachloride, n-butyl titanate, methoxytitanium trichloride, butoxytitanium trichloride, etc.

The main component of the catalyst and the co-catalyst prepared according to the invention jointly compose the high-efficiency polyethylene catalyst of the invention. The cocatalyst can be selected from one or more organic metal compounds, such as organic zinc, organic magnesium, organic aluminum compounds. It can be triethylaluminum, diethylaluminum chloride, triisobutylaluminum, trihexylaluminum, diethylzinc, etc.; it is preferably an organoaluminum compound. The ratio of the co-catalyst to the catalyst main component is Al/Ti=20-400 (molar ratio), preferably 30-300 (molar ratio).

The high-efficiency catalyst of the invention can be directly used in the slurry polymerization process of ethylene to produce full-density polyethylene. The polymerization temperature is kept at 50°C-100°C, preferably 60°C-90°C; the total pressure during polymerization is 0.7-1.5MPa. If low and medium density polyethylene is produced, comonomers can be added for polymerization to adjust the polymer density. Commonly used comonomers are aliphatic alpha-olefins containing 3 to 8 carbon atoms. Suitable α-olefins are propylene, butene-1, pentene-1, hexene-1, 4-methyl-pentene-1, heptene-1 and octene-1, preferably butene-1 and hexene-1. The obtained polymer product has a density of 0.910-0.960 g/ ^cm3 .

To adjust the melt index of the polymers, chain transfer agents can generally be used. The most commonly used chain transfer agent is hydrogen, and diethyl zinc can also be used. The amount of hydrogen used can be adjusted between 0.10 and 0.95 (volume ratio) of the total gas amount, so that polyethylene products with a melt index MI _2.16 between 0 and 300 g/10 minutes can be produced. The high-efficiency polyethylene catalyst of the present invention has high polymerization activity, can reach 300,000 to 900,000 grams of polyethylene/gram of titanium after polymerization at 80°C and a pressure of 0.8 MPa for 4 hours, and has a relatively high bulk density (>0.30 grams/ ^cm3 ).

The high-efficiency polyethylene catalyst of the present invention has the following advantages:

1. The catalyst preparation process is simple and easy, and the operating conditions are not harsh, which is suitable for industrial production and application.

2. The new eco-magnesium halide used in the preparation of the catalyst, after being treated with organic alcohols and alkylaluminum, can obtain a solid complex carrier with more crystal phase defects and uniform spherical particles, so that the final catalyst When used in polymerization reaction, the prepared polymer particles are uniform, almost no fine powder less than 200 mesh is produced, and the bulk density is high.

3. Due to the use of the above-mentioned solid complex carrier, in the presence of electron donors, only a small amount of titanium-containing halides can be used to achieve high titanium loading efficiency, which not only solves the problem of using a large number of titanium-containing halides in actual production The corrosion problem of equipment caused by impregnation with halides, and reduces the difficulty of post-processing work. The catalyst has high catalytic activity.

4. Using this catalyst for polymerization, the reaction is stable, the polymerization temperature is easy to control, and there is no sticking phenomenon.

5. The catalyst has excellent performance, is sensitive to hydrogen adjustment, and has strong copolymerization ability.

The present invention is further illustrated below with examples, but it is not meant to limit the present invention.

Example 1:

(a) preparation of catalyst main component:

The 500 milliliter round-bottomed glass reactor with agitator, condenser and dropping funnel was thoroughly cleaned with nitrogen, and 300 milliliters of n-hexane and 6.5 grams of magnesium powder were added under the protection of nitrogen, and the 70 One milliliter of n-chlorobutane was slowly added to the reactor with stirring. After the addition, the temperature was raised to 40° C. for constant temperature reaction for 8 hours to obtain a neoecological magnesium chloride solid suspension with a structural formula of MgCl ₂ (MgBuCl) _0.45 . Adjust the temperature of the reaction solution to 60° C., slowly add 45 ml of absolute ethanol under stirring, and continue the reaction for 2 hours after the addition. After the reaction was completed, 37 ml of triethylaluminum was slowly added while stirring at the same temperature, and the reaction was continued for 4 hours after the addition to obtain a dark gray solid suspension. 6 milliliters of tetrahydrofuran and 4.1 milliliters of diethylaluminum chloride were added to the reaction solution, and 6.3 grams of titanium tetrachloride was slowly added to the reaction solution at 60° C. under stirring. After the addition, the reaction was carried out at constant temperature for 4 hours. Cool to room temperature and wash with n-hexane three times. A total of 250 milliliters of slurry liquid containing catalyst main components was obtained. The resulting slurry was analyzed to contain 108 mmol/ml of Ti3 ⁺ , 126 mmol/ml ^of Ti, 895 mmol/ml of Mg and 1966 mmol/ml of Cl. Therefore, Ti ³⁺ : ^Titotal :Mg:Cl=0.86:1.0:7.1:15.6 (molar ratio), and the titanium loading rate (ie the molar ratio of the total titanium content obtained by analysis to the added titanium content) reaches 95%.

(b) Polymerization:

Thoroughly purge the 1-liter stainless steel reaction vessel with high-purity nitrogen. Afterwards, in the reaction kettle, add 600 milliliters of dry industrial hexanes, 15 milliliters of dried high-purity hexene-1, 3.0 millimoles of cocatalyst triethylaluminum and 0.0097 millimoles (in terms of titanium) according to the steps ( a) The prepared catalyst main component. Hydrogen was introduced to a gauge pressure of 0.2MPa, and then ethylene was introduced to control the total pressure to 0.8MPa. The temperature was raised to 80°C, and the polymerization reaction was carried out for 4 hours. A white polyethylene solid was obtained, weighing 187 grams. It can be calculated that the catalytic efficiency is 504,000 g polyethylene/g titanium, the melt index MI _2.16 is 4.4 g/10 min, the density is 0.940 g/ ^cm3 , and the bulk density is 0.326 g/ ^cm3 .

Example 2:

(a) preparation of catalyst main component:

The 500 ml round-bottomed glass reactor with stirrer, condenser, and dropping funnel was fully cleaned with nitrogen, and 300 ml of n-hexane, 6.5 g of magnesium powder and 7 ml of tetrahydrofuran were added under the protection of nitrogen, at 20 56 ml of n-chlorobutane was slowly added to the reactor under stirring. After the addition, the temperature was raised to 40° C. for constant temperature reaction for 8 hours to obtain a nascent magnesium chloride solid suspension with a structural formula of MgCl ₂ (MgBuCl) _0.50 (THF) _0.48 . Adjust the temperature of the reaction solution to 60° C., slowly add 45 ml of absolute ethanol under stirring, and continue the reaction for 2 hours after the addition. After the reaction, keep at this temperature, slowly add 37 milliliters of triethylaluminum while stirring, and continue to react for 4 hours after adding. A suspension of dark gray solid was obtained. 6 milliliters of tetrahydrofuran and 4.1 milliliters of diethylaluminum chloride were added to the reaction solution, and 6.3 grams of titanium tetrachloride was slowly added to the reaction solution at 60° C. under stirring. After the addition, the reaction was carried out at constant temperature for 4 hours. Cool to room temperature and wash with n-hexane three times. A total of 250 milliliters of slurry liquid containing catalyst main components was obtained. The resulting slurry was analyzed to contain 114 mmol/ml of Ti3 ⁺ , 126 mmol/ml ^of Ti, 903 mmol/ml of Mg and 1931 mmol/ml of Cl. Therefore, Ti ³⁺ : ^Titotal :Mg:Cl=0.90:1.0:7.2:15.3 (molar ratio), and the titanium loading ratio (that is, the molar ratio of the total titanium amount obtained by analysis to the added titanium amount) reaches 95%.

(b) Polymerization:

Thoroughly purge the 1-liter stainless steel reaction vessel with high-purity nitrogen. After that, add 600 milliliters of dried industrial hexane, 4.4 millimoles of cocatalyst triethylaluminum and 0.01455 millimoles (calculated as titanium) of the main catalyst component prepared in step (a) in the reactor. Hydrogen was introduced to a gauge pressure of 0.2 MPa, followed by ethylene to control the total pressure to 0.8 MPa, the temperature was raised to 80°C, and the polymerization was carried out for 4 hours. A white polyethylene solid was obtained, weighing 183 grams. It can be calculated that the catalytic efficiency is 312,000 g polyethylene/g titanium, the melt index MI _2.16 is 3.2 g/10 minutes, the density is 0.960 g/ ^cm3 , and the bulk density is 0.341 g/ ^cm3 .

Example 3:

The preparation of the catalyst main component and the polymerization conditions were carried out in the same manner as in Example 1, except that the consumption of organic alcohols was changed from 45 milliliters to 90 milliliters in the reprocessing process except for the new eco-magnesium halide. In the obtained slurry of main catalyst components, Ti ³⁺ :Ti ^total :Mg:Cl=0.95:1.0:7.5:16.0 (molar ratio). The results of the polymerization reaction are shown in Table 1.

Example 4:

The preparation of catalyst body component and polymerization reaction condition are carried out by the same method of embodiment 1, except that the consumption of triethylaluminum is changed into 30 milliliters from 37 milliliters in the reprocessing process of new ecological magnesium halide, and the reaction time after adding is extended by 4 hours to 6 hours. In the obtained slurry of main components of the catalyst, Ti ³⁺ :Ti ^total :Mg:Cl=0.80:1.0:7.3:15.9 (molar ratio). The results of the polymerization reaction are shown in Table 1.

Example 5:

The preparation of the main catalyst component and the polymerization conditions were carried out in the same manner as in Example 1, except that the amount of titanium tetrachloride was changed from 6.3 grams to 5 grams in the loading process of titanium-containing halides, and the reaction temperature was raised from 60 ° C to 80 ° C. ℃. In the obtained slurry of the main catalyst components, Ti ³⁺ :Ti ^total :Mg:Cl=0.91:1.0:9.3:19.4 (molar ratio). The results of the polymerization reaction are shown in Table 1.

Embodiment 6:

The preparation of the main catalyst component and the polymerization reaction conditions were carried out in the same manner as in Example 1, except that the type of electron donor was changed from tetrahydrofuran to tributyl phosphate during the loading process of the titanium-containing halide, and the dosage was 18 milliliters, and the obtained catalyst main body In the slurry of components, Ti ³⁺ :Ti ^total :Mg:Cl=0.88:1.0:7.3:15.7 (molar ratio). The results of the polymerization reaction are shown in Table 1.

Table I Example Hydrogen addition MPa Ethylene addition MPa Catalytic efficiency 10,000 grams of polyethylene/gram of titanium Density g/ ^cm3 MI _2.16g /10min Bulk density g/ ^cm3 3 0.20 0.60 43.2 0.943 1.8 0.336 4 0.20 0.60 37.5 0.942 3.2 0.321 5 0.20 0.60 55.7 0.947 2.7 0.347 6 0.20 0.60 28.8 0.937 3.8 0.351

Embodiment 7:

Adopt the catalyst body component that is made by embodiment 1, other polymerization reaction conditions and method remain the same with embodiment 1, change hydrogen addition and control corresponding ethylene addition to carry out experiment, obtain result as table two:

Table II Test No. Hydrogen addition MPa Ethylene addition MPa Catalytic efficiency 10,000 grams of polyethylene/gram of titanium Density g/ ^cm3 MI _2.16g /10min Bulk density g/ ^cm3 7-1 0 0.80 87.1 0.941 0 0.346 7-2 0.10 0.70 65.9 0.938 0.40 0.346 7-3 0.38 0.42 29.2 0.945 15.72 0.315 7-4 0.48 0.32 19.6 0.943 24.30 0.318 7-5 0.60 0.20 8.9 0.944 241.20 0.310

Embodiment 8:

The preparation of the main catalyst component and the polymerization reaction conditions were carried out in the same manner as in Example 2, except that the type of electron donor was changed from tetrahydrofuran to ethyl benzoate during the loading process of the titanium-containing halide, and the dosage was 12 milliliters, and the obtained catalyst main body In the slurry of components, Ti ³⁺ Ti ^total :Mg:Cl=0.9:1.0:7.9:16.2 (molar ratio). The results of the polymerization reaction are shown in Table 3.

Embodiment 9:

The preparation of the main component of the catalyst and the polymerization conditions were carried out in the same manner as in Example 2, except that the type of electron donor was changed from THF to tributyl phosphate and N,N-dimethyl formazan during the loading process of titanium-containing halides. Amides are mixed and used in amounts of 9 milliliters and 3 milliliters respectively. In the slurry of the main catalyst components obtained, Ti3 ^{+ Titotal} :Mg:Cl=0.92:1.0:7.6:17.4 (molar ratio). The results of the polymerization reaction are shown in Table 3.

Table three Example Hydrogen addition MPa Ethylene addition MPa Catalytic efficiency 10,000 grams of polyethylene/gram of titanium Density g/ ^cm3 MI _2.16g /10min Bulk density g/ ^cm3 8 0.2 0.6 27.1 0.960 1.4 0.327 9 0.2 0.6 36.5 0.961 0.9 0.330

Example 10:

Adopt the catalyst body component that is made by embodiment 2, other polymerization reaction conditions and method remain the same with embodiment 1, change hydrogen addition and control corresponding ethylene addition to carry out experiment, obtain result as table four:

Table four Test No. Hydrogen addition amount MPa Ethylene addition MPa Catalytic efficiency 10,000 grams of polyethylene/gram of titanium Density g/ ^cm3 MI _2.16g /10min Bulk density g/ ^cm3 10-1 0 0.80 77.4 0.941 0 0.346 10-2 0.10 0.70 61.2 0.943 1.20 0.350 10-3 0.20 0.60 45.9 0.944 3.40 0.345 10-4 0.40 0.40 26.2 0.940 10.53 0.325 10-5 0.52 0.28 14.6 0.946 33.70 0.318 10-6 0.60 0.20 5.8 0.945 322.0 0.320

Claims (12)

1. A high-efficiency solid catalyst for the production of full-density polyethylene by slurry polymerization, which is composed of a catalyst main component and a co-catalyst, and is characterized in that: (1) Under the protection of nitrogen, commercially available magnesium powder and halogenated alkanes RX are mixed in a hydrocarbon solvent at 10°C to 100°C for 0.5 to 10 hours to prepare a new eco-magnesium halide. Carry out under the existence; The structural formula of new ecological magnesium halide is (RMgX) _p (MgX ₂ ) _q (ED) _t , wherein p: q: t=(0～1.0): 1.0: (0～2.0) (molar ratio), R is an alkyl group containing 3 to 12 carbon atoms, X is a halogen, and ED is an electron donor; the hydrocarbon solvents are aliphatic hydrocarbons, alicyclic hydrocarbons and aromatic hydrocarbons; the halogenated alkane RX is Chloropropane, chlorobutane, chloroisobutane, chloroisopentane, (2) The new ecological magnesium halide prepared according to the above step (1), under the protection of nitrogen, the temperature is controlled at 10°C to 100°C, organic alcohol R'OH is added, and the reaction is stirred for 0.5 to 8 hours to obtain a viscous The brownish-black suspension, and then add alkylaluminum at 20°C to 100°C and stir for 0.5 to 8 hours, and finally form a dark gray complex solid carrier suspension containing magnesium, aluminum, alkoxy and halogen; The organic alcohols R'OH are aliphatic alcohols containing 3 to 12 carbon atoms, and the amount added is R'OH/Mg=0.2 to 6 (molar ratio); the alkyl aluminum is triethylaluminum, triethylaluminum, Isopropylaluminum, triisobutylaluminum, tri-n-octylaluminum, tris(2-ethyl)hexylaluminum, diethylaluminum monochloride, monoethylaluminum dichloride, diisopropylaluminum chloride, double Ethylaluminum semichloride, butylaluminum sesquichloride, the addition amount is R'OH/Al=0.2～7 (molar ratio), (3) Under the protection of nitrogen, add the titanium-containing halide to the complex carrier prepared in the above step (2) in the presence of the electron donor ED and aluminum alkyl, and stir at 20°C to 90°C After reacting for 1-10 hours, the catalyst body component is finally prepared, and the composition ratio of main elements in the catalyst body component is: Ti ³⁺ : Ti ^total : Mg: Cl=(0.7-1.0): 1.0: (2.0-10) : (4.0～25); The described alkylaluminum is triethylaluminum, triisopropylaluminum, triisobutylaluminum, tri-n-octylaluminum, tris(2-ethyl)hexylaluminum, one dichloride Ethylaluminum, monoethylaluminum dichloride, diisopropylaluminum chloride, ethylaluminum sesquichloride, butylaluminum sesquichloride; the titanium-containing halide is Ti(OR") _m Cl _4-m , R" is an alkyl group containing 3 to 4 carbon atoms, m = 0 to 4; the electron donor ED, alkyl aluminum, and titanium-containing halide follow the following molar ratio: ED: Al: Ti:Mg=(0.5～3.0):(0.5～5.0):1:(2.0～10.0), (4) The main component of the catalyst and the co-catalyst form a high-efficiency polyethylene catalyst, which is directly used for ethylene slurry polymerization, and the proportioning of the co-catalyst and the main component of the catalyst is Al/Ti=20～400 (molar ratio); The cocatalyst is an organoaluminum compound. 2. The high-efficiency polyethylene catalyst according to claim 1, characterized in that: said electron donor ED is an organic compound containing at least one oxygen, sulfur, nitrogen, silicon, phosphorus atom. 3. The polyethylene high-efficiency catalyst according to claim 1, characterized in that: the electron donor ED is an aliphatic or aromatic ether, ester, amine, or alcohol containing 3 to 8 carbon atoms. 4. The high-efficiency polyethylene catalyst according to claim 1, characterized in that: the structural formula of the new ecological magnesium halide is (RMgX) _p (MgX ₂ ) _q (ED) _t , wherein p:q:t=( 0.05～0.8):1.0:(0～1.0) (molar ratio), X is chlorine, and ED is an electron donor. 5. The polyethylene high-efficiency catalyst according to claim 1, characterized in that: said hydrocarbon solvent is n-pentane, isopentane, cyclopentane, cyclohexane, benzene. 6. The polyethylene high-efficiency catalyst according to claim 1, characterized in that: the electron donor ED is diethyl ether, tetrahydrofuran, ethyl acetate, ethyl benzoate, tributyl phosphate, isobutanol, N , N-dimethylformamide. 7. The high-efficiency polyethylene catalyst according to claim 1, characterized in that the amount of organic alcohol R'OH is R'OH/Mg=0.5-6 (molar ratio). 8. The polyethylene high-efficiency catalyst according to claim 1, characterized in that: said organic alcohol is methanol, ethanol, 2-methylpentanol, 2-ethylbutanol, 2-ethylhexanol. 9. The high-efficiency polyethylene catalyst according to claim 1, characterized in that the amount of alkylaluminum used is organic alcohols R'OH/Al=0.5-5 (molar ratio). 10. The high-efficiency polyethylene catalyst according to claim 1, characterized in that: the co-catalyst is an organoaluminum compound, which can be triethylaluminum, triisobutylaluminum, diethylaluminum chloride, trihexylaluminum One or a mixture of several. 11. The high-efficiency polyethylene catalyst according to claim 1, characterized in that the ratio of the co-catalyst and the main component of the catalyst to form the high-efficiency catalyst is Al/Ti=30-300 (molar ratio). 12. The high-efficiency polyethylene catalyst according to claim 1, characterized in that the titanium-containing halide is titanium tetrachloride, n-butyl titanate, methoxytitanium trichloride, butoxytitanium trichloride.