Method and system for anaerobic filling of fixed bed reactor catalyst

Abstract

The invention relates to a method and a system for anaerobic filling of a fixed bed reactor catalyst. The method comprises the following steps: S1, mixing a catalyst and solid carbon dioxide in an external filling container to obtain a filling mixture; and S2, enabling the filling mixture to enter a fixed bed reactor, and carrying out catalyst filling. The catalyst filling work of the fixed bed reactor can be completed through a simple method under the condition that air is isolated, it is guaranteed that the catalyst does not make contact with oxygen, the performance is not damaged, the safety of the filling process is guaranteed, and therefore normal reaction and the service life of the catalyst are not affected.

Description

Technical Field

[0001] The present application relates to the field of catalyst loading, and in particular, to a method and system for anaerobic loading of catalysts in a fixed bed reactor. Background Art

[0002] Fixed bed reactors are widely used in the petrochemical industry. At present, the method of loading catalysts in fixed bed reactors is usually to load the catalysts from the top of the reactor and let the catalysts fall. Manual loading is the most common method. There are generally three methods: bag method, spiral method, and spring method. The bag method is to place the catalyst in a canvas bag, manually place it on the top of the reaction tube, loosen the bag mouth, and let the catalyst fall. This loading method is less efficient. The spiral method and the spring method are to design a loading internal component, and the loading is completed with the help of different structural forms of the internal components. In these loading methods, the catalyst is in an air atmosphere, which is not suitable for the loading of reducing metals, catalysts that will burn or explode when in contact with air, and catalysts that must avoid contact with air during the loading process. When facing the loading of catalysts that cannot come into contact with air, the existing loading methods cannot meet the requirements.

[0003] The quality of catalyst use directly affects the quality and output of products, and even safe production. One of the reasons for improper use of catalysts is improper catalyst loading, which causes the catalyst performance to be damaged, thus affecting the normal progress of the reaction and the service life of the catalyst.

[0004] CN101711963A discloses a fixed bed dense phase filling device, in which the catalyst is thrown out by centrifugal force during the rotation of the turntable, thereby forming a uniform material surface in the reactor.

[0005] CN201521034191.X discloses a catalyst loading machine including a feed hopper, a storage hopper, a feed pipe, a bracket, a first adjustment plate, and a second adjustment plate. By arranging nitrogen pipelines on the feed hopper and the feed pipe to allow nitrogen of a certain pressure to be introduced when loading the catalyst, the reducing catalyst can be prevented from contacting with air during the loading process. However, the feed hopper is not completely isolated from the air, and there is still a risk of contact with the air.

[0006] Although the above disclosed loading methods can complete the catalyst loading of the fixed bed reactor, they cannot solve the problem of anaerobic loading in which the catalyst does not contact oxygen. When the catalyst required for the reaction cannot contact oxygen, the existing disclosed loading methods cannot meet the requirements. Summary of the invention

[0007] The purpose of the present disclosure is to provide a method and system for anaerobic loading of catalysts in a fixed bed reactor, which can avoid the performance being destroyed due to contact with oxygen during the catalyst loading process, and solve the current problem of difficulty in loading catalysts containing active metals in the industry.

[0008] In order to achieve the above object, the present disclosure provides a method for oxygen-free loading of a catalyst in a fixed bed reactor in a first aspect, comprising the following steps:

[0009] S1, mixing the catalyst and solid carbon dioxide in an external filling container to obtain a filling mixture;

[0010] S2, allowing the loading mixture to enter a fixed bed reactor for catalyst loading.

[0011] Optionally, the weight ratio of the catalyst to the solid carbon dioxide in the external filling container is 1:(0.1-100), preferably 1:(0.5-10).

[0012] Optionally, in step S1, the external filling container is a container with a stirring function; the mixing conditions include: a temperature of -30 to 100°C, preferably 0 to 40°C; a stirring speed of 10 to 200 rpm, preferably 30 to 100 rpm; a mixing time of 1 to 200 minutes, preferably 5 to 60 minutes; a working pressure of 0.1 to 5 MPa, preferably 0.1 to 0.5 MPa; and an inert atmosphere is inside the external filling container.

[0013] Optionally, in step S2, the conditions for catalyst loading include: an operating temperature of -30 to 100°C, preferably 0 to 80°C, a temperature rise in the fixed bed reactor during loading of less than 5°C, preferably less than 1°C; a pressure of 0.1 to 10MPa, preferably 0.1 to 5MPa; and an introduction rate of the loading mixture of 1 to 1000Kg / min, preferably 5 to 200Kg / min.

[0014] Optionally, step S2 further includes:

[0015] During the catalyst loading process, supplementary solid carbon dioxide and supplementary gas are introduced into the fixed bed reactor, wherein the supplementary gas is selected from one or more of an inert gas or a carbon dioxide gas;

[0016] Preferably, the inert gas is introduced through the bottom of the fixed bed reactor, and the supplementary solid carbon dioxide is introduced through the top of the fixed bed reactor.

[0017] Optionally, the amount of inert gas supplemented per hour is 0.1 to 10 times the total volume of the fixed bed reactor; preferably, the amount of inert gas supplemented per hour is 1 to 5 times the total volume of the fixed bed reactor; the amount of solid carbon dioxide supplemented is 0.1 to 100 times, preferably 0.5 to 10 times, the amount of catalyst loaded in the fixed bed reactor;

[0018] Optionally, the inert gas is selected from one or more of nitrogen, argon and helium; the oxygen content of the inert gas is less than 10 ppm, preferably less than 3 ppm; the water content is less than 10 ppm, preferably less than 3 ppm.

[0019] Optionally, the method comprises:

[0020] Loading the catalyst layer by layer from bottom to top in the fixed bed reactor;

[0021] Preferably, the steps include:

[0022] During the filling process of each layer of catalyst, a grid support plate is firstly arranged in the fixed bed reactor, and large ceramic balls and small ceramic balls are filled therein; then the filling mixture is introduced into the fixed bed reactor through a filling pipe for filling.

[0023] Optionally, the catalyst contains an active metal component; preferably, the active metal is selected from one or more of sodium, potassium, lithium, magnesium, aluminum and iron;

[0024] Optionally, the catalyst includes a catalyst for preparing 4-methyl-1-pentene by propylene dimerization.

[0025] The second aspect of the present disclosure provides a system for anaerobic loading of catalyst in a fixed bed reactor, the system comprising an external loading container and a fixed bed reactor; the external loading container comprises a catalyst inlet, a solid carbon dioxide inlet and a loading mixture outlet; the fixed bed reactor comprises a loading mixture inlet; the loading mixture outlet of the external loading container is connected to the loading mixture inlet of the fixed bed reactor;

[0026] The ex-situ filling container is configured to mix the catalyst and solid carbon dioxide in the ex-situ filling container to obtain a filling mixture;

[0027] The fixed bed reactor is configured to allow a charging mixture from an external charging container to enter and perform catalyst charging.

[0028] Optionally, the external filling container comprises one of a catalyst kettle, a circular hopper and a square hopper; preferably, the external filling container is a catalyst kettle with a built-in stirrer; the filling mixture outlet is provided at the lower part of the external filling container, and the filling mixture outlet is connected to the filling mixture inlet of the fixed bed reactor through a filling pipe; optionally, the diameter of the filling pipe is 50 to 300 mm; optionally, the filling pipe is selected from a cloth bag or a metal hose;

[0029] Preferably, the fixed bed reactor further comprises a solid carbon dioxide supplement inlet and an inert gas supplement inlet for supplementing solid carbon dioxide and inert gas during the catalyst loading process.

[0030] Through the above technical scheme, the present disclosure provides a method and system for anaerobic loading of catalyst in a fixed bed reactor, wherein the catalyst is loaded into the fixed bed reactor by using an external loading container and solid carbon dioxide (i.e., dry ice); the catalyst and the solid carbon dioxide are mixed in the external loading container, and then the reactor is loaded with the evenly mixed solid carbon dioxide and catalyst. The present disclosure can complete the catalyst loading work of the fixed bed reactor in an air-tight state by a simple method, thereby ensuring that the catalyst does not contact oxygen and its performance is not damaged, and ensuring the safety of the loading process so as not to affect the normal progress of the reaction and the service life of the catalyst. The present disclosure is suitable for fixed bed reactors that require closed loading of catalysts, and can solve the problem of difficulty in loading catalysts containing active metals.

[0031] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0033] Figure 1 This is a schematic structural diagram of a system for oxygen-free loading of catalyst in a fixed bed reactor provided by the present disclosure;

[0034] Figure 2 It is a structural schematic diagram of the filling system adopted in comparative example 4 of the present disclosure.

[0035] Description of Reference Numerals

[0036] 1-cylinder; 2-upper head; 3-lower head; 4-catalyst kettle; 5-solid carbon dioxide interface of catalyst kettle; 6-catalyst interface of catalyst kettle; 7-vent; 8-reactor solid carbon dioxide interface; 9-inert gas interface; 10-catalyst bed; 11-small ceramic balls; 12-large ceramic balls; 13-grid support plate; 14-catalyst loading tube. DETAILED DESCRIPTION

[0037] The specific embodiments of the present disclosure are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure.

[0038] A first aspect of the present disclosure provides a method for anaerobic loading of a fixed bed reactor catalyst, comprising the following steps:

[0039] S1, mixing the catalyst and solid carbon dioxide in an external filling container to obtain a filling mixture;

[0040] S2, allowing the loading mixture to enter a fixed bed reactor for catalyst loading.

[0041] The present disclosure provides a method for anaerobic loading of catalysts in a fixed bed reactor, wherein the catalyst is loaded into the fixed bed reactor by using an external loading container and solid carbon dioxide; the catalyst and the solid carbon dioxide are mixed in the external loading container, and then the reactor is loaded with the evenly mixed solid carbon dioxide and catalyst. The present disclosure can complete the catalyst loading work of the fixed bed reactor in an air-tight state by a simple method, thereby ensuring that the catalyst does not contact oxygen and its performance is not damaged, and ensuring the safety of the loading process so as not to affect the normal progress of the reaction and the service life of the catalyst. The present disclosure is suitable for fixed bed reactors that require sealed loading of catalysts, and can solve the problem of difficulty in loading catalysts containing active metals.

[0042] In the present disclosure, after the solid carbon dioxide (i.e., dry ice) introduced into the fixed bed reactor is mixed with the catalyst and introduced into the reactor, the solid carbon dioxide is distributed around the catalyst, and after the solid carbon dioxide is converted into gaseous CO2, a carbon dioxide protection is formed around the catalyst to achieve the effect of blocking air. The gaseous CO2 can further push the air in the reactor to rise during the rising process until it is discharged from the reactor.

[0043] In one embodiment, the catalyst contains an active metal component; preferably, the active metal is selected from one or more of sodium, potassium, lithium, magnesium, aluminum and iron.

[0044] In a specific embodiment, the catalyst includes a catalyst for preparing 4-methyl-1-pentene by propylene dimerization reaction, and the catalyst may include one or both of sodium and potassium.

[0045] The catalyst in the present disclosure can be purchased from commercial channels or prepared by known methods.

[0046] In one embodiment, the weight ratio of the catalyst to the solid carbon dioxide in the external loading container is 1:(0.1-100), preferably 1:(0.5-10). By mixing the catalyst and the solid carbon dioxide according to the weight ratio in this embodiment, an excellent catalyst oxygen-free loading effect can be achieved.

[0047] In one embodiment, in step S1, the external filling container is a container with a stirring function; the mixing conditions include: a temperature of -30 to 100°C; a stirring speed of 10 to 200 rpm; a mixing time of 1 to 200 minutes; a working pressure of 0.1 to 5 MPa, and an inert atmosphere is inside the external filling container.

[0048] In a preferred embodiment, in step S1, the mixing conditions include: temperature of 0 to 40°C; stirring speed of 30 to 100 rpm; mixing time of 5 to 60 minutes; and working pressure of 0.1 to 0.5 MPa. The mixing conditions in this embodiment can achieve a more uniform mixing effect of the catalyst and the solid carbon dioxide in the external filling container.

[0049] In one embodiment, in step S2, the catalyst loading conditions include: an operating temperature of -30 to 100°C, a temperature rise of 5°C or less in the fixed bed reactor during loading; a pressure of 0.1 to 10 MPa; and an introduction rate of the loading mixture of 1 to 1000 Kg / min.

[0050] In a preferred embodiment, in step S2, the catalyst loading conditions include: an operating temperature of 0 to 80°C, a temperature rise of 1°C or less in the fixed bed reactor during loading; a pressure of 0.1 to 5 MPa; and an introduction rate of the loading mixture of 50 to 200 kg / min. According to the conditions of this embodiment, a better loading effect can be ensured.

[0051] In the present disclosure, when the temperature rise during the filling process exceeds the above range, it can be controlled by the following methods, such as adjusting (or increasing) the amount of supplementary solid carbon dioxide (or the ratio to the amount of loaded catalyst) and increasing the inert gas flow rate, so that the temperature rise is within the above temperature rise range of the present disclosure.

[0052] In a preferred implementation, step S2 further includes:

[0053] During the catalyst loading process, supplementary solid carbon dioxide and supplementary gas are introduced into the fixed bed reactor, wherein the supplementary gas is selected from one or more of an inert gas or a carbon dioxide gas;

[0054] Preferably, the inert gas is introduced through the bottom of the fixed bed reactor, and the supplementary solid carbon dioxide is introduced through the top of the fixed bed reactor.

[0055] In one specific embodiment, the amount of inert gas supplemented per hour is 0.1 to 10 times the total volume of the fixed bed reactor; preferably, the amount of inert gas supplemented per hour is 1 to 5 times the total volume of the fixed bed reactor;

[0056] The amount of solid carbon dioxide added is 0.1 to 100 times, preferably 0.5 to 10 times, the amount of catalyst loaded in the fixed bed reactor.

[0057] In a specific embodiment, the inert gas is selected from one or more of nitrogen, argon and helium; the oxygen content of the inert gas is less than 10 ppm, preferably less than 3 ppm; the water content is less than 10 ppm, preferably less than 3 ppm.

[0058] The present disclosure further facilitates avoiding contact between the catalyst and oxygen by supplementing solid carbon dioxide and inert gas during the filling process, and the sources of solid carbon dioxide and inert gas are extensive and easily available.

[0059] In the present disclosure, the bed layer in the fixed bed reactor may be one layer or multiple layers.

[0060] In a specific embodiment, when the reactor is provided with a multi-layer bed, the method comprises:

[0061] Loading the catalyst layer by layer from bottom to top in the fixed bed reactor;

[0062] Preferably, the steps include:

[0063] During the catalyst loading process of each layer, a grid support plate is first installed in the fixed bed reactor, and large and small ceramic balls are loaded; then the loading mixture is introduced into the fixed bed reactor through a loading pipe for filling. After the catalyst loading of the current bed is completed, the grid support plate, large and small ceramic balls are repeatedly installed, and the catalyst loading of the next bed is carried out until the closed reactor is completed. During the repeated installation process, an inert gas is continuously introduced into the reactor to ensure that the loaded catalyst does not come into contact with air.

[0064] In the present disclosure, the grid support plate, the large ceramic balls and the small ceramic balls are all conventional choices in the art, and the arrangement method is also conventional operation in the art.

[0065] The second aspect of the present disclosure provides a system for anaerobic loading of catalyst in a fixed bed reactor, the system comprising an external loading container and a fixed bed reactor; the external loading container comprises a catalyst inlet, a solid carbon dioxide inlet and a loading mixture outlet; the fixed bed reactor comprises a loading mixture inlet; the loading mixture outlet of the external loading container is connected to the loading mixture inlet of the fixed bed reactor;

[0066] The ex-situ filling container is configured to mix the catalyst and solid carbon dioxide in the ex-situ filling container to obtain a filling mixture;

[0067] The fixed bed reactor is configured to allow a charging mixture from an external charging container to enter and perform catalyst charging.

[0068] The fixed bed reactor disclosed in the present invention is a conventional device structure in the art.

[0069] In one embodiment, the external filling container includes one of a catalyst kettle, a circular hopper and a square hopper; preferably, the external filling container is a catalyst kettle with a built-in agitator; the filling mixture outlet is provided at the lower part of the external filling container, and the filling mixture outlet is connected to the filling mixture inlet of the fixed bed reactor through a filling pipe.

[0070] In a specific implementation manner, the diameter of the filling tube is 50 to 300 mm; the filling tube is selected from a cloth bag or a metal hose.

[0071] In a preferred embodiment, the fixed bed reactor further comprises a solid carbon dioxide supplement inlet and an inert gas supplement inlet for supplementing solid carbon dioxide and inert gas or carbon dioxide gas during the catalyst loading process.

[0072] In the present disclosure, a solid carbon dioxide supplementary inlet is disposed at the top of the fixed bed reactor (such as an upper end cap), and an inert gas supplementary inlet is disposed at the bottom of the fixed bed reactor (such as a lower end cap).

[0073] In a specific implementation manner, the present disclosure is used Figure 1 The specific process of the system shown for oxygen-free loading of catalyst in a fixed bed reactor includes:

[0074] The prepared catalyst is added to the catalyst kettle 4 through the catalyst kettle catalyst interface 6, and solid carbon dioxide is added to the kettle through the catalyst kettle solid carbon dioxide interface 5 at this time, the operating temperature and pressure in the kettle are adjusted to appropriate values, and the stirring kettle is started to stir, and the solid carbon dioxide and the catalyst are stirred evenly. The fixed bed reactor bed layer is first installed with a grid support plate 13, and then the large ceramic balls 12 and the small ceramic balls 11 are loaded, and then the solid carbon dioxide and the catalyst mixed evenly are loaded into the fixed bed reactor through the catalyst loading pipe 14. At the same time, the reactor is supplemented with solid carbon dioxide and inert gas through the reactor solid carbon dioxide interface 8 and the inert gas interface 9, and the inert gas is continuously introduced, and the solid carbon dioxide is continuously supplemented with the loading of the catalyst. After the catalyst loading of the current bed is completed, the grid support plate 13, the large ceramic balls 12 and the small ceramic balls 11 are repeatedly installed, and the catalyst loading of the next bed is carried out until the closed reactor is fully completed.

[0075] The present disclosure is further described in detail by way of examples. The raw materials used in the examples can all be obtained through commercial sources.

[0076] The catalyst is a propylene catalyst prepared by referring to the method disclosed in CN115193462A (specifically Example 4): comprising a carrier and Na and K loaded thereon, the carrier is mixed with a modifier solution through an alkali metal salt, the alkali metal salt is potassium carbonate and sodium carbonate, and the modifier solution is a crown ether solution.

[0077] Dry ice was purchased from commercial sources. Nitrogen gas was used as the inert gas.

[0078] Example 1

[0079] Specifications of external filling container: catalyst kettle with inner diameter of 2000mm and height of 3000mm;

[0080] Specifications of the fixed bed reactor: The inner diameter of the reactor is 3000mm, the height is 6500mm, there are two catalyst beds, and the catalyst filling height of a single bed is 2000mm.

[0081] use Figure 1 The loading system shown in the figure performs oxygen-free loading of catalyst in a fixed bed reactor, specifically comprising the following steps:

[0082] (1) The catalyst and dry ice are mixed in an off-site filling container to obtain a filling mixture; wherein the weight ratio of the catalyst to the dry ice is 1:5; the off-site filling container has a stirring function; the mixing conditions include: a temperature of 25° C., a stirring speed of 50 rpm, a mixing time of 40 min, and a working pressure of 0.2 MPa.

[0083] (2) allowing the loading mixture to enter the fixed bed reactor for catalyst loading; wherein the catalyst loading conditions include: operating temperature of 25°C, controlling the temperature rise in the fixed bed reactor to be below 1°C during the loading process; pressure of 0.2MPa; and introduction rate of the loading mixture of 100Kg / min. During the catalyst loading process, additional dry ice and inert gas are introduced into the fixed bed reactor, and the amount of inert gas added per hour is 3 times the total volume of the fixed bed reactor; the amount of dry ice added is 5 times the amount of catalyst;

[0084] The above process is followed to complete the loading of one layer of catalyst; the reactor of this embodiment is loaded with 2 layers in total.

[0085] After the filling is completed, the reactor is closed until the reaction material is fed to conduct a reaction performance test, which specifically includes the following steps;

[0086] Propylene was used as raw material, and the propylene catalyst prepared above was used to carry out propylene dimerization reaction. The reaction conditions were temperature 155°C, pressure 7Mpa, space velocity 0.6h -1 After the propylene dimerization reaction was stable for 2 hours, the reactor outlet material 4-methyl-1-pentene entered the online chromatographic analyzer for composition analysis to obtain propylene conversion rate data. The propylene conversion rate calculation formula is shown in the following formula (1).

[0087]

[0088] Example 2

[0089] use Figure 1 The loading system shown in the figure performs oxygen-free loading of catalyst in a fixed bed reactor, specifically comprising the following steps:

[0090] (1) The catalyst and dry ice are mixed in an off-site filling container to obtain a filling mixture; wherein the weight ratio of the catalyst to the dry ice is 1:10; the off-site filling container has a stirring function; the mixing conditions include: a temperature of 35° C., a stirring speed of 80 rpm, a mixing time of 50 min, and a working pressure of 0.4 MPa.

[0091] (2) The loading mixture is introduced into a fixed bed reactor for catalyst loading; wherein the catalyst loading conditions include: an operating temperature of 35°C, a temperature rise in the fixed bed reactor during loading is controlled to be below 3°C; a pressure of 0.4MPa; and an introduction rate of the loading mixture of 200Kg / min. During the catalyst loading process, additional dry ice and inert gas are introduced into the fixed bed reactor, and the amount of inert gas added per hour is 5 times the total volume of the fixed bed reactor; the amount of dry ice added is 3 times the amount of catalyst;

[0092] According to the above process, one layer of catalyst is loaded; the reactor of this embodiment is loaded with 2 layers in total. After loading is completed, the reactor is closed until the reaction material is fed to perform the reaction performance test, and the specific process is the same as in Example 1.

[0093] Example 3

[0094] use Figure 1 The loading system shown in the figure performs oxygen-free loading of catalyst in a fixed bed reactor, specifically comprising the following steps:

[0095] (1) The catalyst and dry ice are mixed in an off-site filling container to obtain a filling mixture; wherein the weight ratio of the catalyst to the dry ice is 1:110; the off-site filling container has a stirring function; the mixing conditions include: a temperature of -40°C, a stirring speed of 5 rpm, a mixing time of 250 min, and a working pressure of 0.05 MPa.

[0096] (2) allowing the loading mixture to enter the fixed bed reactor for catalyst loading; wherein the catalyst loading conditions include: operating temperature of -40°C, controlling the temperature rise in the fixed bed reactor to be below 8°C during the loading process; pressure of 0.05MPa; introduction rate of the loading mixture of 1500Kg / min. During the catalyst loading process, additional dry ice and inert gas are introduced into the fixed bed reactor, the amount of inert gas added per hour is 0.05 times the total volume of the fixed bed reactor; the amount of dry ice added is 0.05 times the amount of catalyst;

[0097] According to the above process, one layer of catalyst is loaded; the reactor of this embodiment is loaded with 2 layers in total. After loading is completed, the reactor is closed until the reaction material is fed to perform the reaction performance test, and the specific process is the same as in Example 1.

[0098] Example 4

[0099] This embodiment refers to the method of embodiment 1, and the difference from embodiment 1 is that:

[0100] During the catalyst loading process, no additional dry ice and inert gas were introduced into the fixed bed reactor; the remaining processes and conditions were the same as those in Example 1. After the loading was completed, the reactor was closed until the reaction material was fed to perform the reaction performance test, and the specific process was the same as in Example 1.

[0101] Example 5

[0102] This embodiment refers to the method of Example 1, but differs from Example 1 in that: the catalyst and solid carbon dioxide are mixed in an off-vessel filling container under the following conditions to obtain a filling mixture; wherein the weight ratio of the catalyst to dry ice is 1:50; the off-vessel filling container has a stirring function; the mixing conditions include: a temperature of 60°C, a stirring speed of 150 rpm, a mixing time of 100 min, and a working pressure of 1.0 MPa.

[0103] The remaining process and conditions are the same as those in Example 1. After the filling is completed, the reactor is closed until the reaction material is fed to perform the reaction performance test. The specific process is the same as in Example 1.

[0104] Example 6

[0105] This embodiment refers to the method of embodiment 1, and the difference from embodiment 1 is that: the loading mixture is introduced into the fixed bed reactor for catalyst loading according to the following conditions; the catalyst loading conditions include: the operating temperature is -5°C, and the temperature rise in the fixed bed reactor is controlled to be below 5°C during the loading process; the pressure is 6.0MPa; the introduction rate of the loading mixture is 2Kg / min. During the catalyst loading process, dry ice and inert gas are introduced into the fixed bed reactor, and the amount of inert gas added per hour is 0.5 times the total volume of the fixed bed reactor; the amount of dry ice added is 0.1 times the amount of catalyst;

[0106] The remaining process and conditions are the same as those in Example 1. After the filling is completed, the reactor is closed until the reaction material is fed to perform the reaction performance test. The specific process is the same as in Example 1.

[0107] Comparative Examples 1 to 3

[0108] This comparative example is used to illustrate the catalytic performance of the prepared propylene catalyst after contact with air in a small evaluation device.

[0109] The prepared propylene catalyst was loaded into a 10 ml evaluation device, and after being exposed to air for 0 min (Comparative Example 1), 60 min (Comparative Example 2), and 120 min (Comparative Example 3), nitrogen was purged, and the propylene raw material was preheated and sent to a fixed bed reactor for dimerization to generate 4-methyl-1-pentene. The reaction conditions were temperature 155°C, pressure 7 MPa, and space velocity 0.6 h -1 The materials at the reactor outlet enter the online chromatograph for composition analysis to obtain propylene conversion rate data.

[0110] Comparative Example 4

[0111] Use attached Figure 2 The fixed bed reactor shown has two beds arranged in the reactor, wherein the inner diameter of the reactor is 3000 mm, the height is 6500 mm, and the catalyst loading height of the single bed is 2000 mm.

[0112] The catalyst was exposed to air and loaded into a fixed bed reactor by a bag method. After nitrogen purging, propylene was introduced to start propylene dimerization reaction. After loading, the reactor was closed until the reaction was fed to perform a reaction performance test. The specific process was the same as that in Example 1. When the reaction was stable for 2 hours, the material at the reactor outlet was fed into an online chromatograph for composition analysis to obtain propylene conversion data of the loaded catalyst under an aerobic environment.

[0113] The propylene conversion data obtained in the above comparative examples 1 to 3 are listed in the following table 1. The propylene conversion data obtained in the examples and comparative example 4 are listed in the following table 2.

[0114] Table 1

[0115] Comparative Example 1 Comparative Example 2 Comparative Example 3 Catalyst in aerobic environment time / min 0 60 120 Propylene conversion rate / % 85 40 10

[0116] Table 2

[0117] Propylene conversion rate / % Example 1 85 Comparative Example 4 10 Example 2 83 Example 3 60 Example 4 70 Example 5 78 Example 6 76

[0118] According to the data in Table 1 above, it can be seen that when not in contact with air, the propylene catalyst can achieve a propylene conversion rate of 85%; as the contact time between the catalyst and air increases, the propylene conversion rate decreases accordingly.

[0119] According to the data in Table 2 above, the propylene conversion rate of the reactor loaded with catalyst under aerobic environment in Comparative Example 4 is only 10%, indicating that the catalyst has been seriously deactivated and its life span has been reduced, and it cannot meet the process requirements of long-term operation.

[0120] Example 1 adopts the anaerobic filling method and system provided by the present application, and the propylene conversion rate obtained is 85%, which is the same as the propylene conversion rate obtained in the evaluation device of Comparative Example 1 (without contact with air), indicating that the method provided by the present application achieves the effect of anaerobic filling, the catalyst life can meet the use requirements, and can meet the process requirements of long-term operation.

[0121] Comparing Example 1 with Example 3, it can be seen that Example 1 adopts the mixing conditions and catalyst loading conditions provided by the present disclosure, and the propylene conversion rate of the fixed bed reactor after loading in Example 1 is higher, achieving the effect of anaerobic loading.

[0122] Comparing Example 1 with Example 4, it can be seen that in Example 1, dry ice and inert gas are supplemented during the catalyst loading process. The propylene conversion rate of the fixed bed reactor after loading in Example 1 is higher, and the effect of anaerobic loading is achieved.

[0123] Comparing Example 1 with Example 5 and Example 6, it can be seen that the conditions for mixing the catalyst and solid carbon dioxide in the external filling container and the conditions for loading the mixture into the fixed bed reactor for catalyst loading in Example 1 are both within the optimized process conditions. Compared with Example 5 (the mixing conditions in the external filling container were not optimized) and Example 6 (the catalyst loading was not optimized), the propylene conversion rate in the loaded reactor in Example 1 is the best.

[0124] The preferred embodiments of the present disclosure are described in detail above; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0125] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0126] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A method for anaerobic loading of catalyst in a fixed bed reactor, characterized in that: The following steps are involved: S1, mixing the catalyst and solid carbon dioxide in an external filling container to obtain a filling mixture; S2, allowing the loading mixture to enter a fixed bed reactor for catalyst loading.

2. The method according to claim 1, characterized in that: The weight ratio of the catalyst to the solid carbon dioxide in the external filling container is 1:(0.1-100), preferably 1:(0.5-10).

3. The method according to claim 1, characterized in that In step S1, the external filling container is a container with a stirring function; the mixing conditions include: a temperature of -30 to 100°C, preferably 0 to 40°C; a stirring speed of 10 to 200 rpm, preferably 30 to 100 rpm; a mixing time of 1 to 200 minutes, preferably 5 to 60 minutes; a working pressure of 0.1 to 5 MPa, preferably 0.1 to 0.5 MPa; and an inert atmosphere is inside the external filling container.

4. The method according to claim 1, characterized in that: In step S2, the conditions for loading the catalyst include: an operating temperature of -30 to 100°C, preferably 0 to 80°C; a temperature rise of 5°C or less in the fixed bed reactor during loading, preferably a temperature rise of 1°C or less; a pressure of 0.1 to 10 MPa, preferably 0.1 to 5 MPa; an introduction rate of 1 ～ 1000Kg / min, preferably 5-200Kg / min.

5. The method according to claim 1, characterized in that: Step S2 also includes: During the catalyst loading process, supplementary solid carbon dioxide and supplementary gas are introduced into the fixed bed reactor, wherein the supplementary gas is selected from one or more of an inert gas or a carbon dioxide gas; Preferably, the inert gas is introduced through the bottom of the fixed bed reactor, and the supplementary solid carbon dioxide is introduced through the top of the fixed bed reactor.

6. The method according to claim 5, characterized in that The amount of inert gas supplemented per hour is 0.1 to 10 times the total volume of the fixed bed reactor; preferably, the amount of inert gas supplemented per hour is 1 to 5 times the total volume of the fixed bed reactor; the amount of solid carbon dioxide supplemented is 0.1 to 100 times the amount of catalyst loaded in the fixed bed reactor, preferably 0.5 to 10 times; Optionally, the inert gas is selected from one or more of nitrogen, argon and helium; the oxygen content of the inert gas is less than 10 ppm, preferably less than 3 ppm; the water content is less than 10 ppm, preferably less than 3 ppm.

7. The method according to claim 1, characterized in that The method includes: Loading the catalyst layer by layer from bottom to top in the fixed bed reactor; Preferably, the steps include: During the filling process of each layer of catalyst, a grid support plate is firstly arranged in the fixed bed reactor, and large ceramic balls and small ceramic balls are filled therein; then the filling mixture is introduced into the fixed bed reactor through a filling pipe for filling.

8. The method according to claim 1, characterized in that The catalyst contains an active metal component; preferably, the active metal is selected from one or more of sodium, potassium, lithium, magnesium, aluminum and iron; Optionally, the catalyst includes a catalyst for preparing 4-methyl-1-pentene by propylene dimerization.

9. A system for anaerobic loading of catalyst in a fixed bed reactor, characterized in that: The system comprises an external loading container and a fixed bed reactor; the external loading container comprises a catalyst inlet, a solid carbon dioxide inlet and a loading mixture outlet; the fixed bed reactor comprises a loading mixture inlet; the loading mixture outlet of the external loading container is connected to the loading mixture inlet of the fixed bed reactor; The ex-situ filling container is configured to mix the catalyst and solid carbon dioxide in the ex-situ filling container to obtain a filling mixture; The fixed bed reactor is configured to allow a charging mixture from an external charging container to enter and perform catalyst charging.

10. The system according to claim 9, characterized in that The external filling container comprises one of a catalyst kettle, a circular hopper and a square hopper; preferably, the external filling container is a catalyst kettle with a stirrer installed therein; the filling mixture outlet is arranged at the lower part of the external filling container, and the filling mixture outlet is connected to the filling mixture inlet of the fixed bed reactor through a filling pipe; optionally, the diameter of the filling pipe is 50 to 300 mm; optionally, the filling pipe is selected from a cloth bag or a metal hose; Preferably, the fixed bed reactor further comprises a solid carbon dioxide supplement inlet and an inert gas supplement inlet for supplementing solid carbon dioxide and inert gas during the catalyst loading process.

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