Impurity removal refining device and method

Abstract

The invention discloses an impurity removing and refining device and method. The device comprises a refining tank, a sodium layer arranged in the refining tank, a feed port, a liquid inlet, an exhaust port, a discharge port, an oil discharge port and a weighing device, wherein the feed port, the liquid inlet, the exhaust port, the discharge port, the oil discharge port and the weighing device are formed in the top of the refining tank; the method comprises the following steps: firstly, weighing a sodium layer in which a storage medium is stored, filling a refining agent in an impurity removing and refining device, weighing the impurity removing and refining device, carrying out nitrogen purging, weighing the storage medium from the impurity removing and refining device, inputting a raw material to be refined into the impurity removing and refining device, carrying out impurity removing and refining treatment, and discharging the material after refining is finished, washing the sodium layer, purging, weighing the impurity-removing and refining device, and judging the refining effect and the residual amount of the refining agent according to the weight change of the impurity-removing and refining device before and after refining. According to the impurity refining device and method, the refining effect and the residual amount of the refining agent are determined through a poor-quality method, expensive special instruments are not needed, the storage and replacement operation of the extremely active refining agent is simple and convenient, and the risk of combustion explosion is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of raw material refining, and in particular relates to a device and method for removing impurities and refining. Background Art

[0002] The raw material refining process is an indispensable step in laboratory and industrial polymerization experiments. It is mainly to reduce the content of impurities such as water, sulfur, oxygen, carbon monoxide and unsaturated hydrocarbons in the raw materials, improve the purity of the raw materials, meet the production index requirements, and avoid adverse effects on the polymerization reaction. In industry, there are four main types of polyethylene production methods, high-pressure gas phase method, solution method and slurry method. The PE resins produced by different polymerization process routes have different characteristics and application ranges. In the solution process, the polymer is dissolved in the solvent. The greatest advantage of the solution process is that the product switching time is short and the gel content in the film material is low. It can produce a full range of products (molecular weight distribution from narrow to wide distribution) and very low density polyethylene (i.e. VLDPE, such as PE plastomers and elastomers), which can be copolymerized with advanced α-olefins and show excellent strength, toughness and sealing. In the production process of the chemical industry, the solution process has strict requirements on the water content of the liquid chemical raw materials used in the production process. The raw materials contain impurities such as water, oxygen, carbon monoxide, etc., resulting in the purity of the raw materials failing to meet the polymerization index requirements. Especially in the solution polymerization process, higher requirements are placed on the purity of raw materials. Based on this, the refining process of raw materials is very important.

[0003] The presence of impurities in the raw materials seriously affects the progress of the polymerization reaction. Water can cause the main catalyst titanium trichloride and the activator triethylaluminum to undergo hydrolysis reaction, directly making the main catalyst inactive. The principle of deactivation of the activator triethylaluminum: Al(C2H5)3+H2O→Al(OH)3+C2H6, the main catalyst hydrolyzes when it encounters water, and the deactivation process is: TiCl3+H2O→Ti(OH)3+HCl, so the water content in the raw materials must be effectively controlled. The presence of water also affects the progress of the polymerization reaction, causing the reaction chain to terminate. The presence of oxygen in the raw materials undergoes a redox reaction with the high-efficiency main catalyst, causing it to be poisoned, which directly affects the progress of the polymerization reaction. The poisoning mechanism is: TiCl3+O2→TiOCl2+TiCl4, TiOCl2→TiCl4+TiO. The presence of oxygen not only seriously affects the reaction activity of the main catalyst, but also directly affects the progress of the polymerization reaction after entering the reactor, causing the polymerization reaction chain to terminate. The presence of CO and CO2 in chemical raw materials not only affects the directional ability of the catalyst, but also causes chain termination during the polymerization reaction, reducing the reaction activity of the catalyst.

[0004] The use of sodium metal for refining takes advantage of the active chemical properties of sodium metal. The outermost layer of the sodium atom has only one electron, which is easy to lose, so it has strong reducing properties. Therefore, the chemical properties of sodium are very active and can react with a large number of inorganic substances, most non-metallic elements and most organic substances. When it undergoes redox reactions with other substances, as a reducing agent, the valence of sodium metal increases from 0 to +1 (due to the ns 1 Electron pairs), usually combined in the form of ionic bonds and covalent bonds, have strong metallic properties and weak ionic oxidizing properties.

[0005] Chinese patent CN 106862579 A discloses a sodium reduction device with a heat insulation layer, including a reaction chamber, a furnace cover, a reaction furnace, a furnace shell, a heating wire, a sodium storage tank, a stirring motor, a sodium reflux condenser, a waste sodium storage tank and a vacuum pump. The reaction furnace is provided with a reaction chamber inside, a furnace shell is provided outside the reaction furnace, a furnace cover is provided above the reaction furnace, heating wires are provided at the bottom and sides of the reaction furnace, and a stirring motor is provided above the furnace cover. The technical structure is reasonably designed and easy to operate and use. A reaction chamber is provided in the reaction furnace, a stirring paddle is provided for stirring operation, a sodium input and a sodium reflux condenser are provided above the furnace cover for sodium supply and sodium reflux operation respectively; a heating wire is provided on the bottom and side of the reaction furnace for heating operation, and has great application value. However, the patent does not provide good protection for the use and storage of active metallic sodium. The chemical properties of metallic sodium are very active, and it is very easy to react chemically or even burn and explode. It needs to be stored in a medium such as liquid paraffin or kerosene. This method has the disadvantage of dangerous operation.

[0006] Chinese patent CN 217042518 U discloses a new type of buffer tank for a sodium metal refiner, including a buffer tank body, a first drain pipe, a second drain pipe, a first return pipe, and a second return pipe are arranged on the top of the buffer tank body, the first return pipe and the second return pipe are connected, a valve is arranged between the first return pipe and the second return pipe, the first drain pipe, the second drain pipe, and the first return pipe are connected to the inside of the buffer tank body, an insulation layer is arranged on the outer wall of the buffer tank body, and an electric heating wire is arranged between the outer wall of the buffer tank body and the insulation layer. In the process of processing sodium metal in the refiner, the utility model sets a buffer tank dedicated to sodium metal, collects the sodium metal carried away by the protective gas, and plays a role in avoiding pipeline blockage by recovering the sodium metal and reusing it, thereby preventing accidents caused by blockage of the drain pipe. However, this technology is used for the recovery of sodium metal, and the refiner has a complex structure, is inconvenient to operate, and is not easy to judge the consumption of sodium metal and the refining effect.

[0007] Chinese patent CN 215312283 U discloses a highly efficient and energy-saving alcohol recovery device, including a sodium alcohol reactor, an air outlet pipe, a reflux pipe, a sodium bed and an exhaust pipe, wherein the top of the sodium alcohol reactor is provided with an air outlet pipe, the end of the air outlet pipe is connected to the bottom of the sodium bed, the bottom of the sodium bed is also provided with a reflux pipe, and the top of the sodium bed is provided with an air outlet pipe; the air outlet pipe transports the alcohol gas generated in the sodium alcohol reactor to the sodium bed, and the alcohol volatilized is absorbed by metallic sodium, and the sodium reacts with the alcohol to generate a high-boiling point sodium alcohol and liquefies and refluxes, thereby realizing recovery, and the non-condensable gas is vented through the vent valve of the exhaust pipe; during the reaction process, one end of the straw is inserted into the interior of the reaction liquid through the fixed hole, the reaction liquid is sucked into the straw by squeezing the air bag, and the reaction liquid sucked by the straw is detected; after the reaction is completed, the fixed rod and the cleaning rod are driven to rotate by the movable shaft, and the product on the inner wall of the sodium alcohol reactor can be cleaned up. However, this technology uses sodium reflux to recover alcohols, and does not involve impurity removal and refining. Summary of the invention

[0008] The purpose of the present invention is to overcome the defects of the prior art and provide a device and method for removing impurities. The method uses sodium metal as a refining agent to react chemically with impurities in the raw material to remove impurities such as water, carbon monoxide, carbon dioxide and sulfur in the raw material, solves the hidden danger of operation caused by the extremely active chemical properties of sodium metal, and performs olefin polymerization after the impurity content in the raw material reaches the specification index, thereby improving the polymerization activity of the catalyst and improving the product quality. The method is particularly suitable for the solution method continuous olefin polymerization process and is suitable for the refining of olefin polymerization monomers.

[0009] The invention discloses a decontamination refining device, which comprises: a refining tank, a sodium layer arranged inside the refining tank, a feed inlet, a liquid inlet and an exhaust port, a discharge port, an oil discharge port and a weighing device arranged on the top of the refining tank.

[0010] In the impurity removal and refining device of the present invention, the sodium layer is composed of a tower plate with dense holes, and the tower plate is filled with metallic sodium.

[0011] In the impurity removal and refining device of the present invention, the number of the sodium layers is one, two or more layers, preferably multiple layers.

[0012] In the impurity removal and refining device of the present invention, the top of the refining tank is also provided with a nitrogen inlet; the discharge port is arranged at the bottom of the refining tank; and the oil discharge port is arranged at the middle of one side of the refining tank.

[0013] The impurity removal and refining device of the present invention has a refining tank which is a cylindrical closed tank body with a volume of 1000ml to 10000ml and a pressure resistance of 2 to 5MPa.

[0014] In the impurity removal and refining device of the present invention, metallic sodium and a storage medium are stored in the sodium layer, and the storage medium includes at least one of liquid paraffin, kerosene, mineral oil, and benzene series.

[0015] The impurity removal and refining device of the present invention has a pressure in the refining tank of 0-3.5 MPa, a temperature of 5-90° C., and a feed rate of 0.5-200 cm / min.

[0016] In the impurity removal and refining device of the present invention, the weighing device is an explosion-proof electronic platform scale with a measuring range of 100g to 200kg and a readability accuracy of 1g to 0.1mg, preferably 0.1mg.

[0017] The present invention also provides a method for removing impurities and refining, comprising: firstly weighing the sodium layer and the storage medium filled in the impurity-removing refining device, weighing the refining device filled with the refining agent, purging with nitrogen, discharging the storage medium from the impurity-removing refining device and weighing it, inputting the raw material to be refined into the impurity-removing refining device for impurity-removing refining treatment, discharging the material after the refining is completed, flushing the sodium layer, purging with nitrogen, weighing the impurity-removing refining device, and judging the refining effect and the remaining amount of the refining agent by the weight change of the impurity-removing refining device before and after refining.

[0018] In the impurity removal and refining method of the present invention, when the weight increases before and after weighing, the refining agent reacts chemically with the impurities in the raw material; when the weight does not change before and after weighing, the refining agent has been completely consumed and needs to be replaced and replenished in time.

[0019] In the impurity removal and refining method of the present invention, the refining agent is metallic sodium; the shape of the metallic sodium is preferably block, strip, filament, sphere or sheet.

[0020] In the impurity removal and purification method of the present invention, the solvent for washing the sodium layer is an alkyl liquid compound that does not react with metallic sodium, preferably hexane, isopentane or isobutane.

[0021] The impurity refining device of the present invention is provided with a sodium layer inside and a weighing device, which can weigh before and after refining, and judge the refining effect and the remaining amount of the refining agent by the weight change of the impurity-removing refining device. The impurity-removing refining device method of the present invention removes impurities in the raw material to be refined by a method of chemically reacting impurities in the raw material to be refined with the refining agent in the impurity-removing refining device, so that the refined raw material meets the specifications required for the polymerization test. The impurity-refining device and method of the present invention are advanced in that the refining effect and the remaining amount of the refining agent are determined by the method of mass difference, without the need for expensive special instruments, and the storage and replacement of extremely active refining agents are simple and easy to operate, avoiding the risk of combustion and explosion. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of a miscellaneous refining device according to an embodiment of the present invention.

[0023] Wherein, the reference numerals are:

[0024] Refining tank 1

[0025] Feed port 2

[0026] Discharge port 3

[0027] Sodium layer 4

[0028] Liquid inlet 5

[0029] Exhaust port 6

[0030] Nitrogen inlet 7

[0031] Oil drain port 8 DETAILED DESCRIPTION

[0032] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments to further understand the purpose, solution and effect of the present invention, but it is not intended to limit the scope of protection of the claims attached to the present invention.

[0033] Certain words are used in this specification to refer to specific components or parts. A person of ordinary skill in the art should understand that technical users or manufacturers may refer to the same component or part by different nouns or terms. This specification does not use the difference in name as a way to distinguish components or parts, but uses the difference in function of components or parts as the criterion for distinction. The words "include" and "comprise" mentioned in this specification are open-ended terms and should be interpreted as "including but not limited to". In addition, the word "connect" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connection through other devices.

[0034] It should be noted that, in the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and "about", or "approximately", "substantially", "left and right" and the like indicating directions or positional relationships or parameters are all based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description content, and do not indicate or imply that the referred device or element must have a specific direction, specific size, or be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0035] Figure 1 The structure diagram of the impurity removal refining device of one embodiment of the present invention is shown in FIG. In this embodiment, the impurity removal refining device of the present invention comprises: a refining tank 1, a feed port 2, a discharge port 3, a sodium layer 4, a liquid inlet 5, an exhaust port 6, a nitrogen inlet 7, an oil discharge port 8 and a weighing device (not shown in the figure).

[0036] The refining tank 1 is a cylindrical closed tank with a volume of 1000ml to 10000ml and a pressure resistance of 2 to 5MPa. The pressure inside the refining tank 1 is 0 to 3.5MPa, the temperature is 5 to 90°C, and the feed rate is 0.5 to 200cm / min.

[0037] The feed port 2 is arranged at the top of the refining tank 1 for inputting the raw materials to be refined. The discharge port 3 is arranged at the bottom of the refining tank 1 for outputting the refined materials.

[0038] The sodium layer 4 is arranged inside the refining tank, and the sodium layer 4 is composed of a tower plate with dense holes, and the tower plate is filled with metallic sodium. The sodium layer 4 stores metallic sodium and a storage medium, and the storage medium includes at least one of liquid paraffin, kerosene, mineral oil, and benzene series. However, it is worth noting that the present invention does not particularly limit the number of sodium layers, and the number of sodium layers can be one layer, two layers, or more layers depending on the processing volume.

[0039] The liquid inlet 5 is provided at the top of the refining tank 1 for the entry of the solvent for eluting the sodium layer. The exhaust port 6 is provided at the top of the refining tank 1. The nitrogen inlet 7 is provided at the top of the refining tank 1, and nitrogen is input from the nitrogen inlet 7 to purge the refining tank 1. The oil discharge port 8 is provided in the middle of one side of the refining tank 1 for the discharge of the storage medium.

[0040] The weighing device is preferably an explosion-proof electronic platform scale with a measuring range of 100g to 200kg and a readable accuracy of 1g to 0.1mg, preferably 0.1mg.

[0041] The present invention also provides a method for removing impurities and refining, comprising: firstly weighing the sodium layer and the storage medium filled in the impurity-removing refining device, weighing the refining device filled with the refining agent, purging with nitrogen, discharging the storage medium from the impurity-removing refining device and weighing it, inputting the raw material to be refined into the impurity-removing refining device for impurity-removing refining treatment, discharging the material after the refining is completed, flushing the sodium layer, purging with nitrogen, weighing the impurity-removing refining device, and judging the refining effect and the remaining amount of the refining agent by the weight change of the impurity-removing refining device before and after refining.

[0042] In the impurity removal and refining method of the present invention, when the weight increases before and after weighing, the refining agent reacts chemically with the impurities in the raw material; when the weight does not change before and after weighing, the refining agent has been completely consumed and needs to be replaced and replenished in time.

[0043] In the impurity removal and refining method of the present invention, the refining agent is metallic sodium; the shape of the metallic sodium is preferably block, strip, filament, sphere or sheet.

[0044] In the impurity removal and purification method of the present invention, the solvent for washing the sodium layer is an alkyl liquid compound that does not react with metallic sodium, preferably hexane, isopentane or isobutane.

[0045] The impurity removal and refining device and method of the present invention are applicable to solvents, organic solvents and polymerization monomers of synthetic rubber required for various polymerization reactions. The organic solvent can be selected from at least one of aliphatic hydrocarbon solvents, alcohol solvents, fatty acid ester solvents, ketone solvents, halogenated alkyl solvents and benzene solvents.

[0046] Preferably, the alcohol solvent can be selected from at least one of methanol, ethanol, isopropanol and n-butanol; the fatty acid ester solvent can be selected from at least one of methyl acetate, ethyl acetate, propyl acetate and butyl acetate; the ketone solvent can be selected from at least one of acetone, butanone, methyl ethyl ketone, cyclohexanone, isopropyl ketone, methyl butyl ketone, methyl isobutyl ketone, methyl isobutyl ketone, methyl ethyl ketone, methyl amyl ketone and cyclohexanone; the halogenated alkyl solvent can be selected from at least one of dichloromethane, n-hexane and 1,2-dichloroethane; the benzene solvent can be selected from at least one of benzene, toluene and xylene; the aliphatic hydrocarbon solvent is at least one of n-pentane, isopentane, methylcyclopentane, 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane, 2,2-dimethylbutane, n-hexane, cyclohexane, n-heptane and n-octane.

[0047] Preferably, the solvent for the synthetic rubber is one or more of n-pentane, isopentane, methylcyclopentane, 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane, 2,2-dimethylbutane, n-hexane, cyclohexane, n-heptane and n-octane.

[0048] Preferably, the polymerizable monomers include C5 to C 14 The olefin is preferably at least one of 4-methyl-1-pentene, 1-hexene and 1-octene.

[0049] In the actual production process, the sodium layer 4 and the storage medium of the sodium layer 4 are filled into the refining tank 2, the filled sodium layer 4 and the storage medium of the sodium layer 4 are weighed and recorded, the raw material to be refined enters the impurity removal refining device from the feed port 2, and the raw material is passed through the multi-layer sodium layer 4 at a linear speed of 0.5 to 20 cm / min for impurity removal and refining treatment, and the refined raw material is discharged from the discharge port 3 for further polymerization reaction; after multiple refining, when there is no obvious weight change in the refining tank 1, the exhaust port 6 is opened for exhaust, and the storage medium in the impurity removal refining device is discharged from the oil discharge port 8 and weighed; an alkyl liquid compound that does not react with metallic sodium is injected from the liquid inlet 5 to flush the sodium layer, the valve of the nitrogen inlet 7 is opened, and nitrogen is used for comprehensive purge, and the impurity removal refining device is weighed, and the impurity removal and refining process is completed.

[0050] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A decontamination and refining device, characterized in that: include: A refining tank, a sodium layer arranged inside the refining tank, a feed inlet, a liquid inlet and an exhaust port, a discharge port, an oil discharge port and a weighing device arranged on the top of the refining tank.

2. The impurity removal and refining device according to claim 1, characterized in that: The sodium layer is composed of a tower plate with dense pores, and the tower plate is filled with metallic sodium.

3. The impurity removal and refining device according to claim 1, characterized in that: The number of the sodium layer is one, two or more layers.

4. The impurity removal and refining device according to claim 1, characterized in that: The top of the refining tank is also provided with a nitrogen inlet; the discharge port is arranged at the bottom of the refining tank; and the oil discharge port is arranged at the middle of one side of the refining tank.

5. The impurity removal and refining device according to claim 1, characterized in that: The refining tank is a cylindrical closed tank with a capacity of 1000ml to 10000ml and a pressure resistance of 2 to 5MPa.

6. The impurity removal and refining device according to claim 1, characterized in that: The sodium layer stores metallic sodium and a storage medium, wherein the storage medium includes at least one of liquid paraffin, kerosene, mineral oil, and benzene series.

7. The impurity removal and refining device according to claim 1, characterized in that: The pressure in the refining tank is 0-3.5 MPa, the temperature is 5-90° C., and the feed rate is 0.5-200 cm / min.

8. The impurity removal and refining device according to claim 1, characterized in that: The weighing device is an explosion-proof electronic platform scale with a measuring range of 100g to 200kg and a readable accuracy of 1g to 0.1mg.

9. A method for removing impurities and refining, characterized in that: include: First, the sodium layer and storage medium filled in the impurity removal refining device are weighed, and the refining device filled with the refining agent is weighed and purged with nitrogen. The storage medium is discharged from the impurity removal refining device and weighed, and the raw material to be refined is input into the impurity removal refining device for impurity removal refining treatment. After the refining is completed, the material is discharged, the sodium layer is flushed, purged with nitrogen, and the impurity removal refining device is weighed. The refining effect and the remaining amount of refining agent are judged by the weight change of the impurity removal refining device before and after refining.

10. The impurity removal and purification method according to claim 9, characterized in that: When the weight increases before and after weighing, the refining agent reacts chemically with the impurities in the raw materials; when the weight does not change before and after weighing, the refining agent has been completely consumed and needs to be replaced and replenished in time.

11. The impurity removal and purification method according to claim 9, characterized in that: The refining agent is metallic sodium; the shape of the metallic sodium is preferably in the form of blocks, strips, filaments, balls, or sheets.

12. The impurity removal and purification method according to claim 9, characterized in that: The solvent for flushing the sodium layer is an alkyl liquid compound that does not react with metallic sodium.

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