A homogeneous metallocene catalyst preparation system and method

Abstract

The application provides a homogeneous metallocene catalyst preparation system and method. The system comprises a homogeneous metallocene catalyst synthesis unit, a solvent condensation and collection unit and a gas purification unit; the homogeneous metallocene catalyst synthesis unit comprises a fluidized bed reactor; the solvent condensation and collection unit comprises a condenser; and the gas purification unit comprises a fluidized bed gas purifier. The method comprises the following steps: adding a solid metallocene ligand and a solvent into the fluidized bed reactor, introducing a protective gas, spraying a metal ion solution, and generating a homogeneous metallocene catalyst; the protective gas entrains the solvent into the condenser for condensation; and then the protective gas enters the fluidized bed gas purifier for purification. The application adopts double fluidized beds to complete the synthesis of the homogeneous metallocene catalyst and the purification of the gas, reduces the content of water oxygen in the atmosphere of the reaction process of the metallocene ligand and the metal ion, and improves the conversion rate of the active center in the reaction process.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of homogeneous metallocene catalyst, in particular to a homogeneous metallocene catalyst preparation system and method. BACKGROUND

[0002] The homogeneous metallocene catalyst system is a catalyst system taking a five-coordinated compound formed by cyclopentadiene and its derivatives (such as indene, fluorene, etc.) and group IVB transition metal (such as titanium, zirconium, etc.) as a main catalyst, and methylaluminoxane (MAO) or organic boride as a cocatalyst. Compared with the traditional Ziegler-Natta catalyst, the metallocene complex as the main catalyst has more precise control ability, which mainly depends on the structure of the metallocene ligand: on the one hand, the metallocene ligand complexes the fourth group metal to form a single active center; on the other hand, the metallocene ligand "regulates" the spatial geometry around the single active center, thus "regulating" the coordination insertion chain growth reaction of olefin molecules at the active center, and further producing a polymer with high stereoregularity.

[0003] The homogeneous metallocene catalyst, although having many advantages, also has some deficiencies to be overcome: (1) the homogeneous metallocene catalyst (in this case, the metallocene complex as the main catalyst) is extremely sensitive to water and oxygen, and the synthesis conditions are extremely harsh; (2) in the preparation process of the homogeneous metallocene catalyst, the reaction conversion rate of metal ions and ligands is low, resulting in low catalyst synthesis efficiency; (3) the synthesis of the homogeneous metallocene catalyst with complex molecular structure has many steps and long reaction flow, and the byproducts are complex, so the catalyst separation and solvent recovery and regeneration are very difficult.

[0004] In the prior art, the preparation of the homogeneous metallocene catalyst is still in the laboratory stage, and the conventional way is to use standard Schlenk anhydrous and anaerobic technology for the synthesis and processing of all matters related to the metallocene complex and sensitive substances. The anhydrous and anaerobic technology uses high-purity nitrogen gas as the protective gas to perform standard operation through double-tube, and special operation is required to be performed in a glove box. The glass instruments used in the experiment process need to be vacuum baked under a coal gas lamp and cooled to room temperature before use. The anhydrous solvents used in the experiment process need to be specially treated before use. For example, the aprotic solvents such as anhydrous tetrahydrofuran, anhydrous toluene, and anhydrous diethyl ether need to be added with metallic sodium and benzophenone under a high-purity nitrogen atmosphere, refluxed to purple red, and then evaporated into an ampoule containing 4A molecular sieves for storage and standby. For another example, anhydrous n-pentane, n-hexane, and dichloromethane need to be added with an appropriate amount of calcium hydride under a protective gas atmosphere, stirred for 2-3 days, and then evaporated into an ampoule containing 4A molecular sieves for storage and standby.

[0005] CN210058286U discloses a preparation device of a catalyst system. The preparation device comprises a preparation kettle, a feed tank, a gas injection pipeline, a liquid injection pipeline, a liquid level control unit and a pressure control unit. The preparation device can improve the controllability of the complex reaction of gaseous catalyst and liquid promoter and the quality of the catalyst system. The feed tank is located above the preparation kettle, so that the promoter in the feed tank automatically flows into the preparation kettle without external energy, saving energy consumption.

[0006] CN204224504U discloses a preparation device of a metallocene catalyst for producing low-crystal-point polyethylene. The preparation device comprises an alkyl aluminum preparation tank, which is connected with a flow limiting orifice plate, an alkyl aluminum feeding injector and a catalyst carrier preparation tank in sequence. The preparation device can control the feeding rate of alkyl aluminum by adding a flow limiting orifice plate on the pipeline, and ensure the uniform reaction of alkyl aluminum and silica gel by adding an alkyl aluminum feeding injector on the pipeline, so as to obtain a uniform carrier and improve the performance of the catalyst.

[0007] CN112745404A discloses a metallocene catalyst composition and a method for preparing a polyolefin elastomer by using the same. The metallocene catalyst composition comprises a metallocene compound with a single active center and a cocatalyst. When the metallocene catalyst composition is used for the copolymerization of ethylene and 1-octene, the catalyst activity is greater than 1×10 6 g(mPE) / mol(cat)·h, the density of the prepared polyolefin elastomer is 0.865-0.935 g / cm 3 , the number average molecular weight is 104-106 Dalton, and the molecular weight distribution is 1.2-8.5.

[0008] EP0416815A2 discloses a metallocene catalyst and a preparation method thereof. In the catalyst, one Cp ring in a traditional organic metal compound containing a double Cp ring is replaced by a heteroatom N, and the other Cp ring is connected with the N atom by a Si bridge group, forming a spatial four-membered ring structure with geometric tension. The four-membered ring structure limits the free rotation of the Cp ring around the metal center, so that the structure of the catalyst has rigidity, and due to the lack of steric hindrance, the openness of the metal active center is increased, and the insertion rate of long-chain α-olefin comonomer is improved.

[0009] However, the above-mentioned prior art does not provide a solution to the low ion reaction conversion rate and high water oxygen sensitivity in the preparation process of the homogeneous metallocene catalyst. Therefore, developing a new type of homogeneous metallocene catalyst preparation system and method is still one of the problems to be solved in the field. SUMMARY

[0010] To solve the above technical problems, the present application aims to provide a homogeneous metallocene catalyst preparation system and method. The present application uses a double fluidized bed to complete the synthesis of homogeneous metallocene catalyst and the purification of gas, which can reduce the water oxygen content in the atmosphere of the metallocene ligand and metal ion combination reaction process, and improve the conversion rate of active centers in the combination reaction process.

[0011] To achieve the above-mentioned purposes, the first aspect of the present application provides a homogeneous metallocene catalyst preparation system, which at least comprises: a homogeneous metallocene catalyst synthesis unit, a solvent condensation and collection unit, and a gas purification unit.

[0012] The homogeneous metallocene catalyst synthesis unit comprises a fluidized bed reactor, a temperature and pressure detection assembly; the fluidized bed reactor comprises a reactor shell, a gas inlet, a gas outlet, a metallocene ligand feed port, a metal ion solution feed port, a solvent feed port, a discharge port, and a nozzle; the gas inlet and the discharge port are arranged at the lower part of the reactor shell; the metallocene ligand feed port, the metal ion solution feed port, and the solvent feed port are arranged on the side wall of the reactor shell; the gas outlet is arranged at the top of the reactor shell; the nozzle is arranged on the inner wall of the reactor shell; the nozzle is in communication with the metal ion solution feed port; the temperature and pressure detection assembly is arranged at the top of the reactor shell for detecting the temperature and pressure inside the reactor shell.

[0013] The solvent condensation and collection unit comprises a condenser; the condenser is provided with at least a condensing medium inlet, a condensing medium outlet, a gas inlet, a gas outlet, and a solvent outlet; the condensing medium inlet is arranged at the lower part of the condenser, the condensing medium outlet is arranged at the upper part of the condenser, the gas inlet is arranged at the upper part of the condenser, the gas outlet is arranged at the top of the condenser, and the solvent outlet is arranged at the bottom of the condenser.

[0014] The gas purification unit comprises a fluidized bed gas purifier; the fluidized bed gas purifier comprises a purifier shell, a gas inlet, and a gas outlet; the gas inlet is arranged at the lower part of the purifier shell; the gas outlet is arranged at the top of the purifier shell; the interior of the purifier shell has adsorbent particles.

[0015] The gas outlet of the fluidized bed reactor is connected to the gas inlet of the condenser through a pipeline;

[0016] The gas outlet of the condenser is in communication with the gas inlet of the fluidized bed gas purifier through a pipeline;

[0017] The gas outlet of the fluidized bed gas purifier is connected to the gas inlet of the fluidized bed reactor through a pipeline.

[0018] In the homogeneous metallocene catalyst preparation system, preferably, the homogeneous metallocene catalyst synthesis unit and the gas purification unit are respectively further provided with a level detection assembly arranged in the interior of the reactor shell and the interior of the purifier shell.

[0019] In the homogeneous metallocene catalyst preparation system, preferably, the gas purification unit is further provided with a gas impurity detection assembly arranged at the gas outlet of the fluidized bed gas purifier.

[0020] In the homogeneous metallocene catalyst preparation system, preferably, in the fluidized bed reactor, the number of the nozzles is one or more, and the nozzles are arranged on the inner wall of the reactor shell. It is understood by those skilled in the art that when a plurality of nozzles are arranged, the number of the metal ion solution inlets is also a plurality, and each metal ion solution inlet is communicated with a nozzle.

[0021] In the homogeneous metallocene catalyst preparation system, preferably, the interior of the fluidized bed reactor is further provided with a gas distributor located above the gas inlet of the fluidized bed reactor. The gas distributor used is a conventional device in the art, and the specific structure thereof is not particularly limited in the present application.

[0022] In the homogeneous metallocene catalyst preparation system, preferably, a compressor is arranged on the pipeline connecting the gas outlet of the fluidized bed gas purifier and the gas inlet of the fluidized bed reactor.

[0023] In the homogeneous metallocene catalyst preparation system, preferably, the condenser comprises a shell-and-tube condenser. More preferably, the condenser comprises a condenser shell, a plurality of heat exchange tubes and a plurality of baffles, the plurality of heat exchange tubes and the plurality of baffles are arranged in the interior of the condenser shell, the condensing medium inlet and the condensing medium outlet are communicated with the plurality of heat exchange tubes, and the plurality of baffles are arranged staggered along the vertical direction of the condenser shell.

[0024] In the homogeneous metallocene catalyst preparation system, preferably, the top of the condenser is provided with a pressure relief valve.

[0025] In the homogeneous metallocene catalyst preparation system, preferably, the sidewall of the condenser is provided with a gas supplement inlet.

[0026] In the present application, the gas supplement inlet and the pressure relief valve of the condenser can control the pressure of the system, supplement the pressure or release the pressure of the system, and avoid accidents caused by abnormal working conditions such as excessively high system pressure and incomplete condensation.

[0027] In the above homogeneous metallocene catalyst preparation system, preferably, a solution concentration detector is arranged at the solvent outlet of the condenser. The solution concentration detector is used to detect the concentration and composition of the liquid discharged at the solvent outlet of the condenser. The solution concentration detector used can be a conventional device in the art, and the specific structure thereof is not particularly limited in the present application.

[0028] In the above homogeneous metallocene catalyst preparation system, preferably, the baffle plates in the condenser are arranged in a zigzag shape in the vertical direction.

[0029] In the above homogeneous metallocene catalyst preparation system, the adsorbent particles in the interior of the purifier housing are particles capable of adsorbing water and oxygen. Preferably, the adsorbent comprises a molecular sieve. Specifically, the molecular sieve comprises one or a combination of 5A molecular sieve, 3A molecular sieve, 4A molecular sieve, and 13X molecular sieve.

[0030] In the above homogeneous metallocene catalyst preparation system, preferably, the gas purification unit further comprises an initial protective gas delivery pipeline, which is in communication with the gas inlet of the fluidized bed gas purifier, and is used to provide initial protective gas to the system.

[0031] In the above homogeneous metallocene catalyst preparation system, preferably, the gas impurity detection assembly comprises a gas chromatograph and an online sampling probe thereof.

[0032] In the above homogeneous metallocene catalyst preparation system, preferably, the gas purification unit further comprises a protective gas return pipeline, one end of which is connected to the gas impurity detection assembly, and the other end of which is in communication with the gas inlet of the fluidized bed gas purifier, and is used to make the protective gas, the content of water and oxygen of which does not meet the requirements after being detected by the gas impurity detection assembly, re-enter the fluidized bed gas purifier for purification.

[0033] In the above homogeneous metallocene catalyst preparation system, preferably, the interior of the fluidized bed gas purifier is further provided with a gas distributor, which is located above the gas inlet of the fluidized bed gas purifier. The gas distributor used can be a conventional device in the art, and the specific structure thereof is not particularly limited in the present application.

[0034] In the above homogeneous metallocene catalyst preparation system, preferably, the solvent outlet of the condenser is connected to the solvent feed inlet of the fluidized bed reactor through a pipeline.

[0035] In the above-mentioned homogeneous metallocene catalyst preparation system, the temperature and pressure detecting assembly, the material level detecting assembly in the homogeneous metallocene catalyst synthesis unit, and the material level detecting assembly in the gas purification unit are all conventional devices in the art, and the present application does not specially limit the specific structure thereof.

[0036] According to the specific embodiment of the present application, preferably, the above-mentioned system further comprises a ligand synthesis unit for synthesizing metallocene ligands. The ligand synthesis unit can adopt the ligand synthesis device in the prior art, and the present application does not specially limit the structure thereof.

[0037] According to the specific embodiment of the present application, preferably, the above-mentioned system further comprises a recrystallization unit for recrystallizing and purifying the metallocene ligands synthesized by the ligand synthesis unit. The recrystallization unit can adopt the device in the prior art, and the present application does not specially limit the structure thereof. The recrystallization unit can be connected to the metallocene ligand feeding port of the fluidized bed reactor through a pipeline.

[0038] According to the specific embodiment of the present application, preferably, the above-mentioned system further comprises a raw material storage unit including a storage device for the raw materials for synthesizing ligands, a storage device for metal ion solution, and a storage device for solvent, etc.; the storage device for the raw materials for synthesizing ligands is connected to the ligand synthesis unit; the storage device for metal ion solution is connected to the metal ion solution feeding port of the fluidized bed reactor, and the storage device for solvent is connected to the solvent feeding port of the fluidized bed reactor. These storage devices can all adopt the storage devices in the prior art, and the present application does not specially limit the structure thereof.

[0039] According to the specific embodiment of the present application, preferably, the above-mentioned system further comprises a raw material refining unit connected to the raw material storage unit for refining the raw materials for synthesizing ligands, the raw materials for synthesizing metal ion solution, and solvent, etc. The raw material refining unit can adopt the raw material refining device in the prior art, and the present application does not specially limit the structure thereof.

[0040] According to the specific embodiment of the present application, preferably, the system further comprises a solvent recovery unit connected to the solvent outlet of the condenser by a pipeline for recovering the solvent. The recovered solvent can be returned to the raw material refining unit, the raw material storage unit, and then returned to the homogeneous metallocene catalyst synthesis unit again, so as to realize the reuse of the solvent. Those skilled in the art can understand that the solvent recovered by the solvent recovery unit includes the solvent in the metal ion solution and the solvent entering the system from the solvent feeding port of the fluidized bed reactor. In addition, those skilled in the art can understand that when the system of the present application does not comprise a solvent recovery unit, the solvent outlet of the condenser can be directly connected to the solvent feeding port of the fluidized bed reactor by a pipeline, as described above.

[0041] According to the specific embodiment of the present application, preferably, the system further comprises a catalyst storage unit connected to the discharge port of the fluidized bed reactor by a pipeline for storing the prepared homogeneous metallocene catalyst.

[0042] In the present application, the fluidized bed refers to suspending a large number of solid particles in a moving fluid, so that the particles have certain apparent characteristics of the fluid. Specifically, when the velocity of the fluid through the bed layer gradually increases to a certain value, the particles become loose, the interstitial space between the particles increases, and the volume of the bed layer expands. If the fluid velocity is further increased, the bed layer will not be able to maintain a fixed state. At this time, the particles are all suspended in the fluid and show quite irregular motion. With the increase of the flow rate, the motion of the particles becomes more and more intense, and the expansion of the bed layer also increases, but the particles still stay in the bed layer and are not taken out by the fluid. At this time, the state of the bed layer is similar to that of a liquid. This fluid-solid contact state is called solid fluidization, i.e. fluidized bed.

[0043] The fully fluidized bed exhibits properties similar to those of a liquid. The fluidized bed in the present application has the following characteristics: the fluid with a density smaller than the average density of the bed layer can be suspended on the bed surface; the bed surface remains horizontal; the bed layer obeys the hydrostatic relationship, i.e. the pressure difference △p of two sections with a height difference L is ρgL; the particles have similar fluidity to liquids; there is dispersed fluidization; the two interconnected fluidized beds used in the present application can automatically adjust the upper surface of the bed layer to be on the same horizontal plane.

[0044] The homogeneous metallocene catalyst preparation system provided by the application completes the synthesis of the homogeneous metallocene catalyst and the purification of the gas by using double fluidized beds. In the catalyst synthesis process of the application, the metal ion solution and the metallocene ligand can be fully contacted, and because the temperature in the fluidized bed reactor is uniform and the concentration of the reaction system is uniform, the reaction can be fully carried out, the conversion rate of the active center in the chemical reaction process is improved, that is, the conversion rate of the ion reaction is improved. In the gas purification process of the application, the protective gas and the adsorbent particles can be fully contacted, the content of impurities such as water and oxygen in the gas is greatly reduced, and the purified gas is suitable for being used as the reaction atmosphere in the synthesis process of the homogeneous metallocene catalyst. Moreover, by using the homogeneous metallocene catalyst preparation system of the application, the prepared catalyst is easy to separate, and the recovery of the solvent is simple and efficient. Therefore, the application solves the problems of low ion reaction conversion rate and high water and oxygen content in the atmosphere in the synthesis process of the homogeneous metallocene catalyst in the prior art. The application improves the synthesis efficiency and yield of the homogeneous metallocene catalyst, improves the purity of the homogeneous metallocene catalyst, and reduces the cost of the catalyst.

[0045] The second aspect of the application provides a homogeneous metallocene catalyst preparation method, which is a method for preparing a homogeneous metallocene catalyst by using the homogeneous metallocene catalyst preparation system described above, and the method comprises the following steps:

[0046] (1) adding a solid metallocene ligand and a solvent into the fluidized bed reactor, then introducing a protective gas into the fluidized bed reactor, the protective gas being the protective gas purified by the fluidized bed gas purifier, the protective gas strongly disturbing the solid metallocene ligand to form a fluidized bed, spraying a metal ion solution in the form of mist droplets into the fluidized bed reactor through the nozzle, the metal ion reacting with the metallocene ligand to generate a homogeneous metallocene catalyst, and the protective gas carrying the solvent being discharged from the gas outlet of the fluidized bed reactor;

[0047] (2) the protective gas carrying the solvent discharged from the gas outlet of the fluidized bed reactor entering the condenser, the protective gas obtained after condensation being discharged from the gas outlet of the condenser, and the solvent obtained being discharged from the solvent outlet of the condenser;

[0048] (3) the protective gas discharged from the gas outlet of the condenser entering the fluidized bed gas purifier, the adsorbent particles in the fluidized bed gas purifier being strongly disturbed to form a fluidized bed, the adsorbent particles adsorbing water and oxygen in the protective gas, the purified protective gas being discharged from the gas outlet of the fluidized bed gas purifier, and the discharged protective gas entering the fluidized bed reactor.

[0049] In the preparation method described above, preferably, in step (1), the reaction temperature in the fluidized bed reactor is -40 to 40℃.

[0050] In the above preparation method, preferably, in step (1), the reaction pressure in the fluidized bed reactor is 0.1-2 MPa.

[0051] In the above preparation method, the temperature and pressure in the fluidized bed reactor can be detected by a temperature and pressure detection assembly on the top of the fluidized bed reactor.

[0052] In the above preparation method, preferably, in step (1), the fluidization velocity in the fluidized bed reactor is 0.1-5 m / s. Those skilled in the art can understand that the fluidization velocity refers to the superficial velocity of the fluid formed by the solid metallocene ligand.

[0053] In the above preparation method, preferably, in step (1), the crystal size of the solid metallocene ligand is 10-100 μm.

[0054] In the above preparation method, preferably, in step (1), the particle size of the solid metallocene ligand is 500-5000 μm.

[0055] In the above preparation method, preferably, in step (1), the ratio of the amount of the solid metallocene ligand to the amount of the solvent is 50-500 g: 1 L.

[0056] In the above preparation method, preferably, in step (1), the concentration of the metal ions in the metal ion solution is 0.1-100 g / L.

[0057] In some embodiments of the present application, the solid metallocene ligand, the solvent and the metal ion solution can all be conventional raw materials for preparing homogeneous metallocene catalysts in the art, and the present application does not specially limit the alternative specific compounds thereof.

[0058] In the above preparation method, preferably, in step (2), the temperature in the condenser is -50 to 50°C.

[0059] In the above preparation method, preferably, in step (2), the pressure in the condenser is 0.1-2 MPa. The pressure in the condenser can be adjusted by a pressure relief valve on the top of the condenser and / or by supplementing a protective gas through a gas supplementing port.

[0060] In the above preparation method, preferably, in step (2), the residence time of the solvent entrained by the protective gas discharged from the gas outlet of the fluidized bed reactor in the condenser is 0.1-20 min. The residence time in the condenser can ensure that the solvent entrained by the protective gas is fully settled, and therefore the pipeline in the condenser should be designed to be long enough to ensure that the solvent can be fully settled.

[0061] In the above preparation method, preferably, in step (2), the flow rate of the solvent entrained in the protective gas in the condenser is below 1 m / min. If the flow rate is too fast, it will have an adverse effect on the settling of the solvent entrained in the protective gas.

[0062] According to the specific embodiments of the present application, the solvent entrained in the protective gas is condensed and recovered by sub-cooling, so as to ensure that all the gaseous solvent is completely liquefied. The residence time of the protective gas is increased by using a folded-plate condenser, and the recovery efficiency of the solvent is improved.

[0063] In the above preparation method, preferably, in step (3), the temperature in the fluidized bed gas purifier is -50 to 50℃.

[0064] In the above preparation method, preferably, in step (3), the pressure in the fluidized bed gas purifier is 0.1-2 MPa.

[0065] In the above preparation method, preferably, in step (3), the fluidization velocity in the fluidized bed gas purifier is 0.1-5 m / s. Those skilled in the art can understand that the fluidization velocity refers to the superficial velocity of the fluid formed by the adsorbent particles.

[0066] In the above preparation method, preferably, step (3) further comprises: detecting the content of water and oxygen in the protective gas at the gas outlet of the fluidized bed gas purifier by the gas impurity detection assembly, and if the content of water and oxygen does not meet the requirements, then making the protective gas re-enter the fluidized bed gas purifier for purification. More preferably, if the content of water in the protective gas is less than 5 ppm, and the content of oxygen is less than 5 ppm, then it meets the requirements.

[0067] According to the specific embodiments of the present application, the protective gas is purified by using a fluidized bed gas purifier. In the purification process, the protective gas strongly disturbs the adsorbent particles (such as molecular sieve, etc.) to form a fluidized bed, and then efficiently adsorbs water and oxygen in the protective gas. The protective gas that does not meet the water and oxygen content requirements is re-purified, and the protective gas that meets the water and oxygen content requirements enters the fluidized bed reactor.

[0068] In the above preparation method, preferably, in step (3), the purified protective gas discharged from the gas outlet of the fluidized bed gas purifier is compressed by a compressor and then enters the fluidized bed reactor. More preferably, the pressure of the purified protective gas after being compressed by the compressor is 0.1-2 MPa, and the temperature is -50 to 50℃. The present application uses a compressor to provide the pressure of the entire reaction system.

[0069] In the above preparation method, preferably, the protective gas comprises one or a combination of several of nitrogen, helium, neon and the like.

[0070] In the above preparation method, preferably, the prepared homogeneous metallocene catalyst (i.e., metallocene complex) has a crystal size of 10-100 μm and a particle size of 500-5000 μm.

[0071] The present application provides a homogeneous metallocene catalyst preparation system and method. The present application uses a double fluidized bed to complete the synthesis of the homogeneous metallocene catalyst and the purification of the gas, reduces the water oxygen content in the atmosphere during the combination reaction process of the metallocene ligand and the metal ion, improves the conversion rate of the active center during the combination reaction process, and can realize the efficient, green and stable synthesis of the homogeneous metallocene catalyst. The homogeneous metallocene catalyst preparation system and method of the present application are particularly suitable for the production of the homogeneous metallocene catalyst for synthesizing polyolefin elastomers.

[0072] The technical solution of the present application has at least the following beneficial effects:

[0073] The ion reaction conversion rate of the homogeneous metallocene catalyst and the water oxygen content of the reaction system determine the purity and synthesis efficiency of the catalyst. The present application uses a double fluidized bed to complete the synthesis of the homogeneous metallocene catalyst and the purification of the gas, realizes the deep purification of the atmosphere and the efficient combination of the metal ion and the metallocene ligand. Therefore, the technical solution of the present application improves the synthesis efficiency and yield of the homogeneous metallocene catalyst, improves the purity of the homogeneous metallocene catalyst, and reduces the cost of the catalyst. The purity of the homogeneous metallocene catalyst provided by the present application is more than 97%, and the yield is more than 85%. In addition, the technical solution of the present application makes the prepared catalyst easy to separate, and makes the recovery of the solvent simple and efficient. BRIEF DESCRIPTION OF DRAWINGS

[0074] Figure 1 It is a structure schematic view of the homogeneous metallocene catalyst preparation system in the embodiment of the present application.

[0075] Explanation of reference numerals:

[0076] 1-fluidized bed reactor; 2-temperature and pressure detection assembly; 3-first material level detection assembly; 11-nozzle; 12-first gas distributor;

[0077] 4-condenser; 41-baffle; 42-pressure relief valve; 43-gas supplement port;

[0078] 5-fluidized bed gas purifier; 51-second gas distributor; 6-gas impurity detection assembly; 7-second material level detection assembly; 8-compressor; 9-initial protective gas delivery pipeline; 10-protective gas return pipeline. DETAILED DESCRIPTION

[0079] In order to have a clearer understanding of the technical features, objectives and benefits of the present application, the technical solutions of the present application are described in detail as follows, but should not be understood as limiting the scope of the present application.

[0080] Some embodiments of the present application provide a homogeneous metallocene catalyst preparation system, which has a structure as shown in Figure 1 The system at least comprises: a homogeneous metallocene catalyst synthesis unit, a solvent condensation and collection unit, and a gas purification unit.

[0081] The homogeneous metallocene catalyst synthesis unit comprises a fluidized bed reactor 1 and a temperature and pressure detection assembly 2. The fluidized bed reactor 1 comprises a reactor shell, a gas inlet, a gas outlet, a metallocene ligand feed port, a metal ion solution feed port, a solvent feed port, a discharge port, and a nozzle 11. The gas inlet and the discharge port are arranged at the lower part of the reactor shell. The metallocene ligand feed port, the metal ion solution feed port, and the solvent feed port are arranged at the side wall of the reactor shell. The gas outlet is arranged at the top of the reactor shell. The nozzle 11 is arranged at the inner wall of the reactor shell. The nozzle 11 is in communication with the metal ion solution feed port. The temperature and pressure detection assembly 2 is arranged at the top of the reactor shell, and is used to detect the temperature and pressure inside the reactor shell.

[0082] The solvent condensation and collection unit comprises a condenser 4. The condenser 4 is provided with at least a condensing medium inlet, a condensing medium outlet, a gas inlet, a gas outlet, and a solvent outlet. The condensing medium inlet is arranged at the lower part of the condenser 4, the condensing medium outlet is arranged at the upper part of the condenser 4, the gas inlet is arranged at the upper part of the condenser 4, the gas outlet is arranged at the top of the condenser 4, and the solvent outlet is arranged at the bottom of the condenser 4.

[0083] The gas purification unit comprises a fluidized bed gas purifier 5. The fluidized bed gas purifier 5 comprises a purifier shell, a gas inlet, and a gas outlet. The gas inlet is arranged at the lower part of the purifier shell, and the gas outlet is arranged at the top of the purifier shell. The interior of the purifier shell has adsorbent particles.

[0084] The gas outlet of the fluidized bed reactor 1 is connected to the gas inlet of the condenser 4 through a pipeline.

[0085] The gas outlet of the condenser 4 is in communication with the gas inlet of the fluidized bed gas purifier 5 through a pipeline.

[0086] The gas outlet of the fluidized bed gas purifier 5 is connected to the gas inlet of the fluidized bed reactor 1 through a pipeline.

[0087] In an embodiment, the homogeneous metallocene catalyst synthesis unit further comprises a first material level detection assembly 3 arranged inside the reactor shell.

[0088] In one embodiment, the gas purification unit further includes a second material level detection component 7, which is disposed inside the purifier housing.

[0089] In one embodiment, the gas purification unit further includes a gas impurity detection component 6, which is disposed at the outlet of the fluidized bed gas purifier 5.

[0090] In one embodiment, in the fluidized bed reactor 1, there are one or more nozzles 11, all disposed on the inner wall of the reactor shell. Those skilled in the art will understand that when multiple nozzles 11 are provided, there are also multiple metal ion solution inlets, each connected to one of the multiple nozzles 11.

[0091] In one embodiment, a first gas distributor 12 is further provided inside the fluidized bed reactor 1, and the first gas distributor 12 is located above the air inlet of the fluidized bed reactor 1. The gas distributor used is a conventional device in the art, and the present invention does not specifically limit its structure.

[0092] In one embodiment, a compressor 8 is installed on the pipeline connecting the outlet of the fluidized bed gas purifier 5 to the inlet of the fluidized bed reactor 1.

[0093] In one embodiment, the condenser 4 is a shell-and-tube condenser. Specifically, the condenser 4 includes a condenser shell and a plurality of heat exchange tubes ( Figure 1 (Not shown in the image) and several baffles 41, several heat exchange tubes, and several baffles 41 are disposed inside the condenser shell. The condensing medium inlet and outlet are connected to several heat exchange tubes. The several baffles 41 are staggered along the vertical direction of the condenser shell, and the several baffles 41 can be sealed and fitted with several heat exchange tubes. The several baffles 41 form a baffle group in a zigzag shape in the vertical direction. The condensing medium can be conventional in the art, such as, but not limited to, water.

[0094] In one embodiment, a pressure relief valve 42 is provided on the top of the condenser 4.

[0095] In one embodiment, the side wall of the condenser 4 is provided with a gas inlet 43.

[0096] The gas inlet 43 and pressure relief valve 42 of the condenser 4 can control the system pressure, replenish or release pressure to the system, and avoid accidents caused by abnormal operating conditions such as excessive system pressure or incomplete condensation.

[0097] In one embodiment, a solution concentration detector is provided at the solvent outlet of the condenser 4 for detecting the concentration and composition of the liquid discharged at the solvent outlet of the condenser. The solution concentration detector used is a conventional device in the art, and the present application does not make any special limitation on its specific structure.

[0098] In one embodiment, the adsorbent particles inside the purifier housing are particles capable of adsorbing water and oxygen. Preferably, the adsorbent comprises a molecular sieve. In particular, the molecular sieve comprises one or a combination of 5A molecular sieve, 3A molecular sieve, 4A molecular sieve and 13X molecular sieve, etc.

[0099] In one embodiment, the gas purifying unit further comprises an initial protective gas delivery line 9, which is in communication with the gas inlet of the fluidized bed gas purifier 5 for providing initial protective gas into the system.

[0100] In one embodiment, the gas impurity detection assembly 6 comprises a gas chromatograph and its on-line sampling probe.

[0101] In one embodiment, the gas purifying unit further comprises a protective gas return line 10, one end of which is connected to the gas impurity detection assembly 6, and the other end of which is in communication with the gas inlet of the fluidized bed gas purifier 5 for re-feeding the protective gas, whose water and oxygen content does not meet the requirements after detection by the gas impurity detection assembly 6, into the fluidized bed gas purifier 5 for further purification.

[0102] In one embodiment, the interior of the fluidized bed gas purifier 5 is further provided with a second gas distributor 51, which is located above the gas inlet of the fluidized bed gas purifier 5. The gas distributor used is a conventional device in the art, and the present application does not make any special limitation on its specific structure.

[0103] In one embodiment, the solvent outlet of the condenser 4 is connected to the solvent feed inlet of the fluidized bed reactor 1 (not shown) through a pipeline. Figure 1

[0104] In the above embodiments, the temperature and pressure detection assembly 2 and the first level detection assembly 3 in the homogeneous metallocene catalyst synthesis unit, and the second level detection assembly 7 in the gas purifying unit are conventional devices in the art, and the present application does not make any special limitation on their specific structures.

[0105] In the above embodiments, necessary valves such as stop valves, etc. can be provided on the pipelines, and the person skilled in the art can make conventional settings according to the actual situation.

[0106] ​In one embodiment, the system further comprises a ligand synthesis unit for synthesizing the metallocene ligand. The ligand synthesis unit can employ a ligand synthesis device known in the art, and the present application does not specially limit the structure thereof.

[0107] In one embodiment, the system further comprises a recrystallization unit for recrystallizing and purifying the metallocene ligand synthesized by the ligand synthesis unit. The recrystallization unit can employ a device known in the art, and the present application does not specially limit the recrystallization unit. The recrystallization unit can be connected to the metallocene ligand inlet of the fluidized bed reactor by a pipeline.

[0108] In one embodiment, the system further comprises a raw material storage unit including a storage device for raw materials for synthesizing the ligand, a storage device for the metal ion solution, and a storage device for the solvent, etc.; the storage device for the raw materials for synthesizing the ligand is connected to the ligand synthesis unit; the storage device for the metal ion solution is connected to the metal ion solution inlet of the fluidized bed reactor, and the storage device for the solvent is connected to the solvent inlet of the fluidized bed reactor. These storage devices can employ storage devices known in the art, and the present application does not specially limit the storage devices.

[0109] In one embodiment, the system further comprises a raw material refining unit connected to the raw material storage unit for refining the raw materials for synthesizing the ligand, the raw materials for synthesizing the metal ion solution, and the solvent, etc. The raw material refining unit can employ a raw material refining device known in the art, and the present application does not specially limit the structure thereof.

[0110] In one embodiment, the system further comprises a solvent recovery unit connected to the solvent outlet of the condenser by a pipeline for recovering the solvent. The recovered solvent can be returned to the raw material refining unit, the raw material storage unit, and then returned to the homogeneous metallocene catalyst synthesis unit again, so as to realize the reuse of the solvent. Those skilled in the art can understand that the solvent recovered by the solvent recovery unit includes the solvent in the metal ion solution and the solvent entering the system from the solvent inlet of the fluidized bed reactor. In addition, those skilled in the art can understand that, when the system of the present application does not comprise the solvent recovery unit, the solvent outlet of the condenser can be directly connected to the solvent inlet of the fluidized bed reactor by a pipeline, as described above.

[0111] In one embodiment, the system further comprises a catalyst storage unit connected to the discharge outlet of the fluidized bed reactor by a pipeline for storing the prepared homogeneous metallocene catalyst.

[0112] The other specific embodiments of the present application provide a method for preparing a homogeneous metallocene catalyst, which is a method for preparing the homogeneous metallocene catalyst by using the above-mentioned system for preparing a homogeneous metallocene catalyst, and the method comprises the following steps:

[0113] (1) The solid metallocene ligand and the solvent are added into the fluidized bed reactor 1, and then the protective gas is introduced into the fluidized bed reactor 1, wherein the protective gas is the protective gas purified by the fluidized bed gas purifier 5, the protective gas strongly disturbs the solid metallocene ligand to form a fluidized bed, the metal ion solution is sprayed in the form of mist droplets onto the bed layer of the fluidized bed reactor 1 through the nozzle 11, the bed temperature of the fluidized bed reactor 1 is adjusted by the feed temperature and the reaction heat, and the metal ion is attached to the solid metallocene ligand to react and generate the homogeneous metallocene catalyst, and the protective gas carrying the solvent is discharged from the gas outlet of the fluidized bed reactor 1;

[0114] (2) The protective gas carrying the solvent discharged from the gas outlet of the fluidized bed reactor 1 enters the condenser 4, and the obtained protective gas is discharged from the gas outlet of the condenser 4 after being condensed, and the obtained solvent is discharged from the solvent outlet of the condenser 4;

[0115] (3) In the initial stage of preparation, the protective gas is introduced into the fluidized bed gas purifier 5 through the initial protective gas conveying pipeline 9, and after the amount of the protective gas meets the reaction requirements of the fluidized bed reactor 1, the protective gas is no longer provided through the initial protective gas conveying pipeline 9, and the protective gas discharged from the gas outlet of the condenser 4 enters the fluidized bed gas purifier 5, the protective gas strongly disturbs the adsorbent particles in the fluidized bed gas purifier 5 to form a fluidized bed, the adsorbent particles adsorb water and oxygen in the protective gas to obtain the purified protective gas and discharge the purified protective gas from the gas outlet of the fluidized bed gas purifier 5, the content of water and oxygen in the protective gas at the gas outlet of the fluidized bed gas purifier 5 is detected by the gas impurity detection assembly 6, if the content of water and oxygen does not meet the requirements, the protective gas is introduced into the fluidized bed gas purifier 5 again for purification, wherein if the content of water in the protective gas is less than 5 ppm and the content of oxygen is less than 5 ppm, the requirements are met, and the protective gas meeting the requirements of the content of water and oxygen is compressed by the compressor 8 and then introduced into the fluidized bed reactor 1.

[0116] In the present embodiment, in step (1), the reaction temperature in the fluidized bed reactor 1 is -40 to 40℃, and specifically 0℃. The reaction pressure in the fluidized bed reactor 1 is 0.1 to 2 MPa, and specifically 0.5 MPa. The temperature and pressure in the fluidized bed reactor 1 can be detected by the temperature and pressure detection assembly 2 at the top of the fluidized bed reactor 1. The fluidization velocity in the fluidized bed reactor 1 is 0.1 to 5 m / s, and specifically 2 m / s. Those skilled in the art can understand that the fluidization velocity refers to the superficial velocity of the fluid formed by the solid metallocene ligand.

[0117] In the present embodiment, in step (1), the crystal size of the solid metallocene ligand is 10 to 100 μm, and specifically about 50 μm. The particle size of the solid metallocene ligand is 500 to 5000 μm, and specifically 2000 to 3000 μm. The ratio of the amount of the solid metallocene ligand to the solvent is 50 to 500 g: 1 L, and specifically 100 g: 1 L. The concentration of the metal ions in the metal ion solution is 0.1 to 100 g / L, and specifically 50 g / L.

[0118] In the present embodiment, the solid metallocene ligand, the solvent, and the metal ion solution can all use conventional raw materials for preparing homogeneous metallocene catalysts in the art, and the present application does not specially limit the specific compounds that can be selected.

[0119] In the present embodiment, in step (2), the temperature in the condenser 4 is -50 to 50℃, and specifically 0℃. The pressure in the condenser 4 is 0.1 to 2 MPa, and specifically 1 MPa. The pressure in the condenser can be adjusted by the pressure relief valve 42 at the top of the condenser 4 and / or by supplementing the protective gas through the gas supplement port 43. The residence time of the protective gas carrying the solvent in the condenser 4 is 0.1 to 20 min, and specifically 10 min. The flow rate of the protective gas carrying the solvent in the condenser 4 is 1 m / min or less.

[0120] In the present embodiment, the solvent carried in the protective gas is condensed and recovered by over-condensation, so as to ensure that all gaseous solvents are completely liquefied. The residence time of the protective gas is increased by using a folded-plate condenser, and the recovery efficiency of the solvent is improved.

[0121] In the present embodiment, in step (3), the temperature in the fluidized bed gas purifier 5 is -50 to 50℃, and specifically 0℃. The pressure in the fluidized bed gas purifier 5 is 0.1 to 2 MPa, and specifically 0.5 MPa. The fluidization velocity in the fluidized bed gas purifier 5 is 0.1 to 5 m / s, and specifically 2 m / s. Those skilled in the art can understand that the fluidization velocity refers to the superficial velocity of the fluid formed by the adsorbent particles.

[0122] According to the specific embodiment of the present application, the present application adopts the fluidized bed gas purifier to purify the protective gas. In the process of purification, the protective gas strongly disturbs the adsorbent particles (such as molecular sieve, etc.) to form a fluidized bed, and then efficiently adsorbs the water and oxygen in the protective gas, and makes the protective gas not meeting the water and oxygen content requirements to be purified again, and the protective gas meeting the water and oxygen content requirements enters the fluidized bed reactor.

[0123] In the present embodiment, in step (3), the pressure of the protective gas after being compressed by the compressor 8 is 0.1-2 MPa, specifically 0.5 MPa; the temperature is -50 to 50℃, specifically 0℃. The present embodiment adopts the compressor 8 to provide the pressure of the whole reaction system.

[0124] In the present embodiment, the protective gas is nitrogen.

[0125] In the present embodiment, the prepared homogeneous metallocene catalyst has a crystal size of about 50 μm and a particle size of 2000-3000 μm.

[0126] It is detected that the purity of the homogeneous metallocene catalyst provided by the present embodiment is more than 97%, and the yield is more than 85%.

Claims

1. A homogeneous metallocene catalyst preparation system comprising at least: The homogeneous metallocene catalyst synthesis unit, the solvent condensation and collection unit, and the gas purification unit; The homogeneous metallocene catalyst synthesis unit comprises a fluidized bed reactor and a temperature and pressure detection assembly; the fluidized bed reactor comprises a reactor shell, a gas inlet, a gas outlet, a metallocene ligand feed port, a metal ion solution feed port, a solvent feed port, a discharge port, and a nozzle; the gas inlet and the discharge port are arranged at the lower part of the reactor shell; the metallocene ligand feed port, the metal ion solution feed port, and the solvent feed port are arranged at the sidewall of the reactor shell; the gas outlet is arranged at the top of the reactor shell; the nozzle is arranged at the inner wall of the reactor shell; the nozzle is in communication with the metal ion solution feed port; the temperature and pressure detection assembly is arranged at the top of the reactor shell and used for detecting the temperature and pressure inside the reactor shell; The solvent condensation and collection unit comprises a condenser; the condenser is provided with at least a condensing medium inlet, a condensing medium outlet, a gas inlet, a gas outlet, and a solvent outlet; the condensing medium inlet is arranged at the lower part of the condenser, the condensing medium outlet is arranged at the upper part of the condenser, the gas inlet is arranged at the upper part of the condenser, the gas outlet is arranged at the top of the condenser, and the solvent outlet is arranged at the bottom of the condenser; The gas purification unit comprises a fluidized bed gas purifier, a gas impurity detection assembly, an initial protective gas delivery pipeline, and a protective gas return pipeline; the fluidized bed gas purifier comprises a purifier shell, a gas inlet, and a gas outlet; the gas inlet is arranged at the lower part of the purifier shell; the gas outlet is arranged at the top of the purifier shell; the interior of the purifier shell is provided with adsorbent particles; the gas impurity detection assembly is arranged at the gas outlet of the fluidized bed gas purifier; The gas outlet of the fluidized bed reactor is connected to the gas inlet of the condenser through a pipeline; The gas outlet of the condenser is in communication with the gas inlet of the fluidized bed gas purifier through a pipeline; The gas outlet of the fluidized bed gas purifier is connected to the gas inlet of the fluidized bed reactor through a pipeline; The initial protective gas delivery pipeline is in communication with the gas inlet of the fluidized bed gas purifier and is used to provide initial protective gas to the system; One end of the protective gas return pipeline is connected to the gas impurity detection assembly, and the other end is in communication with the gas inlet of the fluidized bed gas purifier, so that the protective gas whose water and oxygen content does not meet the requirements after being detected by the gas impurity detection assembly reenters the fluidized bed gas purifier for purification.

2. The homogeneous metallocene catalyst preparation system of claim 1, wherein, The homogeneous metallocene catalyst synthesis unit and the gas purification unit further comprise a material level detection assembly arranged inside the reactor shell and the purifier shell, respectively.

3. The homogeneous metallocene catalyst preparation system of claim 1, wherein, In the fluidized bed reactor, the number of nozzles is one or more, and each nozzle is arranged at the inner wall of the reactor shell.

4. The homogeneous metallocene catalyst preparation system of claim 1, wherein, A compressor is arranged on the pipeline connecting the gas outlet of the fluidized bed gas purifier to the gas inlet of the fluidized bed reactor.

5. The homogeneous metallocene catalyst preparation system of claim 1, wherein, The condenser comprises a shell-and-tube condenser.

6. The homogeneous metallocene catalyst preparation system of claim 5, wherein, The condenser comprises a condenser shell, a plurality of heat exchange tubes and a plurality of baffles, the plurality of heat exchange tubes and the plurality of baffles are arranged inside the condenser shell, the condensing medium inlet and the condensing medium outlet are communicated with the plurality of heat exchange tubes, and the plurality of baffles are arranged staggeredly along the vertical direction of the condenser shell.

7. The homogeneous metallocene catalyst preparation system of claim 1, wherein, A pressure relief valve is arranged at the top of the condenser.

8. The homogeneous metallocene catalyst preparation system of claim 1, wherein, An air supplementing port is arranged on the sidewall of the condenser.

9. The homogeneous metallocene catalyst preparation system of claim 1, wherein, A solution concentration detector is arranged at the solvent outlet of the condenser.

10. The homogeneous metallocene catalyst preparation system of claim 6, wherein, The plurality of baffles in the condenser form a baffle group in the shape of a zigzag line in the vertical direction.

11. The homogeneous metallocene catalyst preparation system of claim 1, wherein, The adsorbent comprises molecular sieve.

12. A method for preparing a homogeneous metallocene catalyst, the method being a method for preparing a homogeneous metallocene catalyst by using the homogeneous metallocene catalyst preparation system according to any one of claims 1-11, The method comprises the following steps: (1) adding solid metallocene ligand and solvent into the fluidized bed reactor, then introducing a protective gas into the fluidized bed reactor, the protective gas being a protective gas purified by the fluidized bed gas purifier, the protective gas strongly disturbing the solid metallocene ligand to form a fluidized bed, spraying a metal ion solution in the form of mist droplets into the fluidized bed reactor through the nozzle, the metal ion reacting with the metallocene ligand to generate a homogeneous metallocene catalyst, and the protective gas carrying the solvent being discharged from the gas outlet of the fluidized bed reactor; (2) the protective gas carrying the solvent discharged from the gas outlet of the fluidized bed reactor entering the condenser, the protective gas obtained after condensation being discharged from the gas outlet of the condenser, and the solvent obtained being discharged from the solvent outlet of the condenser; (3) the protective gas discharged from the gas outlet of the condenser entering the fluidized bed gas purifier, the adsorbent particles in the fluidized bed gas purifier being strongly disturbed to form a fluidized bed, the adsorbent particles adsorbing water and oxygen in the protective gas to obtain purified protective gas and discharge the purified protective gas from the gas outlet of the fluidized bed gas purifier, and the discharged protective gas entering the fluidized bed reactor; after detecting the content of water and oxygen in the protective gas at the gas outlet of the fluidized bed gas purifier by the gas impurity detection assembly, if the content of water and oxygen does not meet the requirements, the protective gas re-enters the fluidized bed gas purifier for purification.

13. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (1), the reaction temperature in the fluidized bed reactor is -40 to 40℃.

14. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (1), the reaction pressure in the fluidized bed reactor is 0.1-2 MPa.

15. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (1), the fluidization speed in the fluidized bed reactor is 0.1-5 m / s.

16. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (1), the crystal size of the solid metallocene ligand is 10-100 μm.

17. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (1), the particle size of the solid metallocene ligand is 500-5000 μm.

18. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (1), the ratio of the use amount of the solid metallocene ligand to the solvent is 50-500 g: 1 L.

19. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (1), the metal ion concentration in the metal ion solution is 0.1-100 g / L.

20. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (2), the temperature in the condenser is -50 to 50℃.

21. The homogeneous metallocene catalyst preparation process of claim 12 wherein, In step (2), the pressure in the condenser is 0.1-2 MPa.

22. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (2), the residence time of the solvent entrained by the protective gas discharged from the gas outlet of the fluidized bed reactor in the condenser is 0.1-20 min.

23. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (3), the temperature in the fluidized bed gas purifier is -50 to 50℃.

24. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (3), the pressure in the fluidized bed gas purifier is 0.1-2 MPa.

25. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (3), the fluidization velocity in the fluidized bed gas purifier is 0.1-5 m / s.

26. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (3), the protective gas meets the requirements if the content of water is less than 5 ppm and the content of oxygen is less than 5 ppm.

27. The homogeneous metallocene catalyst preparation process of claim 12, wherein, In step (3), the purified protective gas discharged from the gas outlet of the fluidized bed gas purifier is compressed by a compressor and then enters the fluidized bed reactor.

28. The homogeneous metallocene catalyst preparation process of claim 27, wherein, In step (3), the pressure of the purified protective gas after compression by the compressor is 0.1-2 MPa, and the temperature is -50 to 50℃.

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