Regeneration method and decolorization method of silica gel for rubber polymer solution

Abstract

The invention discloses a regeneration method and a decolorization method of silica gel for a rubber polymer solution. The regeneration method comprises the following steps: washing adsorbed silica gel by using a non-polar solvent; the non-polar solvent is selected from at least one of aliphatic hydrocarbons; drying the washed silica gel to obtain dry silica gel; contacting the obtained dry silica gel with a polar solvent for silica gel decoloration; the polar solvent is selected from one or more of ethers, halogenated alkanes, furans and esters. The regeneration method disclosed by the invention is simple in treatment process and easy to industrialize. The regenerated silica gel is low in chromaticity and good in reuse effect.

Description

Technical Field

[0001] This invention relates to the field of chemical regeneration technology, and more specifically, to a method for regenerating and decolorizing silica gel for rubber polymer solutions. Background Technology

[0002] Silica gel possesses excellent adsorption properties and a high surface area, making it widely used in the chemical, pharmaceutical, and food industries, with decolorization being its most prevalent application. Silica gel particles are spherical and porous, capable of adsorbing organic substances such as dyes, impurities, and pigments, thus decolorizing them. Silica gel decolorization is widely used for various liquid and solid organic substances, such as chemicals, pharmaceuticals, food, and alcoholic beverages. However, directly discarding silica gel after adsorbing colored substances would have adverse environmental impacts and increase product production costs.

[0003] Currently, there are several methods for regenerating silica gel after it has adsorbed colored substances: The first method is alkaline boiling, but the quality of the recovered silica gel is not high, and the structure of the silica gel is easily damaged, resulting in a significant reduction in the efficiency of decolorization; the second method is high-temperature calcination, which causes serious pollution from exhaust gas emissions; the third method is solvent extraction, which is more targeted, but requires different extractants depending on the different production systems and pigments adsorbed by the silica gel. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems of complex processing steps, low processing efficiency, and poor elution effect of existing extractants on the specific pigments in rubber polymers adsorbed by silica gel in the prior art. This invention provides a method for decolorizing and regenerating silica gel in rubber polymer solutions. This regeneration method can reduce the content of colored substances in silica gel, simplify the processing steps, improve the processing efficiency, and realize the recovery of silica gel.

[0005] To achieve the above objectives, the first aspect of the present invention provides a method for regenerating silica gel for rubber polymer solutions, the regeneration method comprising the following steps:

[0006] The adsorbed silica gel is washed with a non-polar solvent; the non-polar solvent is selected from at least one of aliphatic hydrocarbons.

[0007] The washed silica gel is dried to obtain dry silica gel;

[0008] The obtained dry silica gel is decolorized by contacting it with a polar solvent; the polar solvent is selected from one or more of ethers, haloalkanes, furans and esters.

[0009] A second aspect of the present invention provides a method for decolorizing a rubber polymer solution, the method comprising the following steps:

[0010] The rubber polymer solution is mixed with silica gel for decolorization;

[0011] The adsorbed silica gel is then separated from the rubber polymer solution;

[0012] The adsorbed silica gel is regenerated using the regeneration method described in the first aspect above.

[0013] The beneficial technical effects achieved by the present invention through the above technical solution are as follows:

[0014] (1) The silica gel regeneration process is simple and efficient.

[0015] (2) The color of the recycled silicone products can be kept at a low level, which ensures the stability of product quality.

[0016] (3) For rubber systems, the same batch of silicone can be regenerated multiple times during use, which significantly reduces the production cost of the decolorization step of rubber products. The rubber products are colorless and transparent and can be applied to high-end manufacturing fields. Attached Figure Description

[0017] Figure 1 These are images of the lithium-based rubber polymer solution in Example 1 before decolorization;

[0018] Figure 2 This is a picture of the lithium-based rubber polymer solution after decolorization in Example 1. Detailed Implementation

[0019] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0020] The first aspect of this invention provides a method for regenerating silica gel for rubber polymer solutions, the regeneration method comprising the following steps:

[0021] The adsorbed silica gel is washed with a non-polar solvent; the non-polar solvent is selected from at least one of aliphatic hydrocarbons.

[0022] The washed silica gel is dried to obtain dry silica gel;

[0023] The obtained dry silica gel is decolorized by contacting it with a polar solvent; the polar solvent is selected from one or more of ethers, haloalkanes, furans and esters.

[0024] According to a preferred embodiment of the present invention, the nonpolar solvent is selected from C6-C. 10One or more of alkanes or cycloalkanes; preferably, the nonpolar solvent is one or more of hexane, cyclohexane, n-heptane, octane, nonane, and decane.

[0025] According to a preferred embodiment of the present invention, the volume ratio of the silica gel adsorbing the colored substance to the nonpolar solvent is 1:1 to 1:10, for example, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, and any value within the range of any two values, preferably 1:2 to 1:5.

[0026] According to a preferred embodiment of the present invention, the washing conditions include: a temperature of 20-60°C, a pressure of 0.03-0.1 MPa, and a time of 1-120 min; preferably, the washing conditions include: a temperature of 40-60°C, a pressure of 0.03-0.05 MPa, and a time of 30-60 min.

[0027] According to the present invention, the washing method can be any method that ensures sufficient contact between the silica gel and the non-polar solvent. Preferably, the washing method is selected from one or more of mechanical stirring, ultrasonication, oscillation, and a fixed bed structure.

[0028] According to a preferred embodiment of the present invention, the drying temperature is 20-60°C and the drying time is 10-240 min; preferably, the drying temperature is 50-60°C and the drying time is 10-180 min.

[0029] According to the present invention, the drying process can be carried out in a vacuum drying oven or a forced-air drying oven.

[0030] According to a preferred embodiment of the present invention, the polar solvent is selected from one or more of diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, dichloromethane, trichloromethane, carbon tetrachloride, tetrahydrofuran, and phthalates.

[0031] Preferably, the polar solvent is a mixed solvent composed of ethers and haloalkanes, wherein the volume ratio of ethers to haloalkanes is 1-5:1, for example, 1:1, 1:2, 1:3, 1:4, 1:5, or any value within the range of any two values.

[0032] Preferably, the polar solvent is a mixed solvent composed of ethers, tetrahydrofurans, and esters, wherein the volume ratio of the ethers, tetrahydrofurans, and esters is 1-5:1-5:1, for example, 1:1:1, 1:2:1, 1:3:1, 1:4:1, 1:5:1, 2:1:1, 2:2:1, 2:3:1, 2:4:1, 2:5:1, 3:3:1, 3:5:1, 4:4:1, 5:4:1, 5:5:1, and any value within the range of any two values.

[0033] According to a preferred embodiment of the present invention, the volume ratio of the dry silica gel to the polar solvent is 1:1-10, for example, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, and any value within the range of any two values, preferably 1:2-5.

[0034] According to a preferred embodiment of the present invention, the conditions for contacting dry silica gel with a polar solvent include: a temperature of 20-60°C, a pressure of 0.03-0.1 MPa, and a time of 10-120 min; preferably, the conditions for contacting dry silica gel with a polar solvent include: a temperature of 30-60°C, a pressure of 0.03-0.05 MPa, and a time of 10-90 min.

[0035] According to the present invention, the contact method is any method that can achieve sufficient contact between the dry silica gel and the polar solvent. Preferably, the contact method is selected from one or more of mechanical stirring, ultrasonication, oscillation, and fixed bed structure.

[0036] According to the present invention, the regeneration method further includes a step of drying the decolorized silica gel, wherein the drying temperature is 20-100℃ and the time is 10min-8h; preferably, the drying temperature is 50-100℃ and the time is 30min-8h.

[0037] According to the present invention, the drying process can be carried out in a vacuum drying oven or a forced-air drying oven.

[0038] According to the present invention, the color of the decolorized silica gel is below 10.

[0039] This invention provides a method for decolorizing a rubber polymer solution, the method comprising the following steps:

[0040] A rubber polymer solution containing colored substances is mixed with silica gel for decolorization;

[0041] The polymer solution was separated from the silica gel that adsorbed the colored substances.

[0042] The silica gel that has adsorbed colored substances is regenerated using the regeneration method described in the first aspect above.

[0043] According to a preferred embodiment of the present invention, the rubber polymer solution is selected from one or more of lithium-based rubber polymers, nickel-based rubber polymers, cobalt-based rubber polymers, and rare earth-based rubber polymers.

[0044] According to a preferred embodiment of the present invention, the rubber polymer solution is diluted before mixing with the silica gel.

[0045] Preferably, the solvent used for dilution is one or a mixture of two or more of hexane, cyclohexane, and heptane; the concentration of the rubber polymer in the diluted solution is 0.5-20 wt%, for example, 0.5 wt%, 1 wt%, 5 wt%, 8 wt%, 10 wt%, 15 wt%, 18 wt%, 20 wt%, and any value within any range of any two values, preferably 5-20 wt%.

[0046] According to a preferred embodiment of the present invention, the amount of silica gel added is 5-20 wt% of the total mass of the diluted rubber polymer solution, for example, 5 wt%, 8 wt%, 10 wt%, 15 wt%, 18 wt%, 20 wt%, and any value within any range of any two values, preferably 10-20 wt%.

[0047] According to a preferred embodiment of the present invention, before mixing the rubber polymer solution with the silica gel, the silica gel is first soaked, washed and dried with a solvent.

[0048] Preferably, the solvent is one or a mixture of two or more of hexane, cyclohexane, and heptane.

[0049] According to the present invention, it is preferable to use a solvent for diluting rubber polymers to soak and wash the silicone to remove impurities from the silicone, and then dry the silicone at a drying temperature of 30℃-60℃.

[0050] According to a preferred embodiment of the present invention, the separation is performed using a funnel with a sand core.

[0051] According to the present invention, the separation method is solid-liquid separation, and preferably a funnel with a sand core is used to achieve the separation of silica gel and adhesive liquid.

[0052] According to this invention, a rubber polymer solution is mixed with silica gel for decolorization. The mixing method can be any method that ensures sufficient contact between the silica gel and the polymer solution, such as mechanical stirring, ultrasound, oscillation, or a fixed-bed structure. The mixing time is 30 minutes to 6 hours. The silica gel and rubber polymer solution are then separated using a solid-liquid separation device. Regeneration is then performed using the regeneration method described in the first aspect, specifically including washing, drying, and extraction. A non-polar solvent is used for washing to remove all polymer adsorbed on the silica gel surface. After drying, a polar solvent is used to extract the colored substances adsorbed on the silica gel, thus regenerating the silica gel, achieving waste utilization, protecting the environment, and increasing revenue.

[0053] After regeneration using the method of this invention, the color of the decolorized silica gel is below 10, and the color of the decolorized rubber polymer solution is below 10.

[0054] According to a particularly preferred embodiment of the present invention, a method for decolorizing a rubber polymer solution specifically includes the following steps:

[0055] (1) Decolorization of rubber solution: A rubber polymer solution containing colored substances is diluted to a certain concentration, a certain mass of silica gel is added, and the mixture is thoroughly mixed to achieve the purpose of decolorization.

[0056] The rubber polymer solution includes, but is not limited to, the following types of rubber polymers: lithium-based, nickel-based, cobalt-based, and rare-earth-based rubber polymers. The concentration of the diluted rubber polymer solution is 0.5-20 wt%.

[0057] The added silica gel needs to be soaked and washed in advance with the solvent used in the rubber polymer system to remove impurities. Then, the silica gel is dried at a temperature of 30℃-60℃. The mass of the added silica gel is 5%-20% of the mass of the diluted adhesive solution.

[0058] (2) Solid-liquid separation: The separation of silica gel and polymer solution in step (1) is achieved by using solid-liquid separation equipment.

[0059] (3) Washing: The silica gel separated from step (2) after adsorbing colored substances is added to a certain amount of non-polar solvent and washed under certain temperature and pressure conditions to wash away all the polymer adsorbed by the silica gel.

[0060] (4) Drying: Dry the washed silica gel obtained in step (3) to obtain dry silica gel.

[0061] (5) Extraction: The dry silica gel obtained in step (4) is added to a certain volume of polar solvent under certain temperature and pressure conditions, and after full contact, the decolorized silica gel is obtained.

[0062] (6) Drying: The silica gel obtained in step (5) is dried to obtain the regenerated silica gel.

[0063] The present invention will be described in detail below through preparation examples and embodiments, but the scope of protection of the present invention is not limited to the following description.

[0064] Unless otherwise specified in the following examples and comparative examples, all conditions were performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments used, unless otherwise specified, are all commercially available products.

[0065] Colorimetry: The platinum-cobalt colorimetric method was used.

[0066] Example 1

[0067] (1) Decolorization of the adhesive: Take 400g of lithium butadiene polymer, dilute it to 20% (wt) with a mixed solvent of hexane and cyclohexane (mass ratio 1:1), add 100g of washed silica gel, and stir mechanically for 30min.

[0068] (2) Solid-liquid separation: The silica gel and the adhesive liquid from step (1) are separated using a funnel with a sand core to obtain a decolorized lithium butadiene polymer solution and silica gel after adsorption of colored substances. Figure 1 and Figure 2 These are images of the lithium-based butadiene polymer solution before and after decolorization. Figure 1 and Figure 2 As can be seen from the comparison, the decolorized lithium-based butadiene polymer solution is almost transparent, indicating that its color intensity is low after decolorization.

[0069] (3) Washing: The silica gel obtained from step (2) after adsorbing the colored substances was added to a mixed solvent of hexane and cyclohexane (mass ratio 1:1). The volume ratio of silica gel to the mixed solvent was 1:2. The pressure was 0.03 MPa, and the silica gel was washed in an ultrasonic bath at 30°C for 30 min.

[0070] (4) Drying: Place the washed silica gel obtained in step (3) into a vacuum drying oven and dry at 50°C for 60 minutes to obtain dry silica gel.

[0071] (5) Extraction: The dry silica gel obtained in step (4) is added to diethyl ether under normal pressure. The volume ratio of silica gel to diethyl ether is 1:3, the pressure is 0.03 MPa, and the silica gel is obtained after sonication for 10 min.

[0072] (6) Drying: Place the silica gel obtained in step (5) into a vacuum drying oven and dry at 50°C for 10 minutes to obtain the regenerated silica gel. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, A1.

[0073] Example 2

[0074] (1) Decolorization of the adhesive: Take 400g of nickel-based butadiene polymer, dilute it to 5% (wt) with n-heptane, add 400g of washed silica gel, and stir mechanically for 30min.

[0075] (2) Solid-liquid separation: The silica gel and the gel solution from step (1) are separated using a funnel with a sand core to obtain a decolorized nickel-based butadiene polymer solution and silica gel after adsorption of colored substances.

[0076] (3) Washing: The silica gel obtained from step (2) after adsorbing the colored substances was added to n-heptane. The volume ratio of silica gel to n-heptane was 1:1. The pressure was 0.04 MPa. The silica gel was mechanically stirred in a three-necked flask at 40°C for 60 min.

[0077] (4) Drying: Place the washed silica gel obtained in step (3) into a vacuum drying oven and dry at 50°C for 120 minutes to obtain dry silica gel.

[0078] (5) Extraction: The dry silica gel obtained in step (4) is added to chloroform under normal pressure. The volume ratio of silica gel to solvent is 1:10. After sonication for 10 min, decolorized silica gel is obtained.

[0079] (6) Drying: Place the silica gel obtained in step (5) into a vacuum drying oven and dry at 50°C for 30 minutes to obtain dry silica gel, which is the regenerated silica gel. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, A2.

[0080] Example 3

[0081] (1) Decolorization of the adhesive: Take 400g of rare earth butadiene polymer, dilute it to 10% (wt) with cyclohexane, add 400g of washed silica gel, and stir mechanically for 50min.

[0082] (2) Solid-liquid separation: The silica gel and the gel liquid from step (1) are separated using a funnel with a sand core to obtain a decolorized rare earth butadiene polymer solution and silica gel after adsorption of colored substances.

[0083] (3) Washing: The silica gel obtained from step (2) after adsorbing the colored substances was added to cyclohexane at a volume ratio of 1:10 and a pressure of 0.03 MPa. The mixture was mechanically stirred in a three-necked flask and washed for 30 min.

[0084] (4) Drying: Place the washed silica gel obtained in step (3) into a vacuum drying oven and dry at 50°C for 60 minutes to obtain dry silica gel.

[0085] (5) Extraction: The dry silica gel obtained in step (4) is added to tetrahydrofuran solvent under normal pressure. The volume ratio of silica gel to solvent is 1:1. After sonication for 10 min, decolorized silica gel is obtained.

[0086] (6) Drying: Place the silica gel obtained in step (5) into a vacuum drying oven and dry at 100°C for 4 hours to obtain dry silica gel, which is the regenerated silica gel. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, A3.

[0087] Example 4

[0088] (1) Decolorization of the adhesive: Take 400g of lithium butadiene polymer, dilute it to 16% (wt) with a mixed solvent of hexane and cyclohexane (mass ratio 1:1), add 500g of washed silica gel, and stir mechanically for 30min.

[0089] (2) Solid-liquid separation: The silica gel and the adhesive liquid from step (1) are separated using a funnel with a sand core to obtain a decolorized lithium butadiene polymer solution and silica gel after adsorption of colored substances.

[0090] (3) Washing: The silica gel obtained from step (2) after adsorbing the colored substances was added to a mixed solvent of hexane and cyclohexane (mass ratio 1:2). The volume ratio of silica gel to the mixed solvent was 1:5. The pressure was 0.03 MPa, and the silica gel was washed in an ultrasonic bath at 30°C for 30 min.

[0091] (4) Drying: Place the washed silica gel obtained in step (3) into a vacuum drying oven and dry at 50°C for 60 minutes to obtain dry silica gel.

[0092] (5) Extraction: The dry silica gel obtained in step (4) is added to a mixed solvent of diethyl ether and chloroform (volume ratio 3:1) under normal pressure. The volume ratio of silica gel to mixed solvent is 1:2. The pressure is 0.03 MPa. After sonication for 10 min, decolorized silica gel is obtained.

[0093] (6) Drying: Place the silica gel obtained in step (5) into a vacuum drying oven and dry at 100°C for 4 hours to obtain the regenerated silica gel. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, A4.

[0094] Example 5

[0095] (1) Decolorization of the adhesive: Take 400g of lithium butadiene polymer, dilute it to 20% (wt) with a mixed solvent of hexane and cyclohexane (mass ratio 1:1), add 100g of washed silica gel, and stir mechanically for 30min.

[0096] (2) Solid-liquid separation: The silica gel and the adhesive liquid from step (1) are separated using a funnel with a sand core to obtain a decolorized lithium butadiene polymer solution and silica gel after adsorption of colored substances.

[0097] (3) Washing: The silica gel obtained from step (2) after adsorbing the colored substances was added to a mixed solvent of hexane and cyclohexane (mass ratio 1:4). The volume ratio of silica gel to the mixed solvent was 1:2. The pressure was 0.03 MPa, and the silica gel was washed in an ultrasonic bath at 30°C for 30 min.

[0098] (4) Drying: Place the washed silica gel obtained in step (3) into a vacuum drying oven and dry at 50°C for 60 minutes to obtain dry silica gel.

[0099] (5) Extraction: The dry silica gel obtained in step (4) is added to a mixed solvent of ethylene glycol methyl ether, tetrahydrofuran and dimethyl phthalate (volume ratio 2:2:1) under normal pressure. The volume ratio of silica gel to mixed solvent is 1:5. The pressure is 0.03 MPa. After sonication for 10 min, decolorized silica gel is obtained.

[0100] (6) Drying: Place the silica gel obtained in step (5) into a vacuum drying oven and dry at 100°C for 8 hours to obtain the regenerated silica gel. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, A5.

[0101] Example 6

[0102] (1) Decolorization of the adhesive: Take 400g of lithium butadiene polymer, dilute it to 20% (wt) with a mixed solvent of hexane and cyclohexane (mass ratio 1:1), add 100g of washed silica gel, and stir mechanically for 30min.

[0103] (2) Solid-liquid separation: The silica gel and the adhesive liquid from step (1) are separated using a funnel with a sand core to obtain a decolorized lithium butadiene polymer solution and silica gel after adsorption of colored substances.

[0104] (3) Washing: The silica gel obtained from step (2) after adsorbing the colored substances was added to a mixed solvent of hexane and cyclohexane (mass ratio 1:5). The volume ratio of silica gel to the mixed solvent was 1:3. The pressure was 0.03 MPa, and the silica gel was washed in an ultrasonic bath at 30°C for 30 min.

[0105] (4) Drying: Place the washed silica gel obtained in step (3) into a vacuum drying oven and dry at 50°C for 60 minutes to obtain dry silica gel.

[0106] (5) Extraction: The dry silica gel obtained in step (4) is added to a mixed solvent of diethyl ether, tetrahydrofuran and dimethyl phthalate (volume ratio 5:2:1) under normal pressure. The volume ratio of silica gel to mixed solvent is 1:3. The pressure is 0.03 MPa. After sonication for 10 min, decolorized silica gel is obtained.

[0107] (6) Drying: Place the silica gel obtained in step (5) into a vacuum drying oven and dry at 100°C for 8 hours to obtain the regenerated silica gel. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, A6.

[0108] Comparative Example 1

[0109] The regeneration method is the same as in Example 1, except that the solvent used for extraction in step (5) is the non-polar solvent hexane. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, D1.

[0110] Comparative Example 2

[0111] The regeneration method is the same as in Example 1, except that the volume ratio of silica gel to solvent in step (5) is 2:1. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in D2 of Table 1.

[0112] Comparative Example 3

[0113] The regeneration method is the same as in Example 1, except that in step (3), the volume ratio of silica gel to mixed solvent is 2:1. The color of the silica gel before and after regeneration, as well as the color of the product after decolorization using the silica gel, are shown in Table 1, D3.

[0114] Table 1

[0115]

[0116] As can be seen from the results in Table 1, the silica gel regenerated using the regeneration method of the present invention has a lower color, and the product treated with the regenerated silica gel also has a lower color.

[0117] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for regenerating silica gel used for a rubber polymer solution, characterized by, The regeneration method comprises the following steps: The washed silica gel is dried to obtain dry silica gel; The dry silica gel is contacted with a polar solvent to decolorize the silica gel; the polar solvent is selected from one or more of ethers, halogenated alkanes, furans and esters. The volume ratio of the adsorbed silica gel to the non-polar solvent is 1:1-10, preferably 1:2-5.

2. The regeneration method according to claim 1, wherein, said non-polar solvent is selected from one or more of C6-C 10 alkanes or cycloalkanes; The washing conditions include a temperature of 20-60°C, a pressure of 0.03-0.1 MPa and a time of 1-120 min.

3. The regeneration method according to claim 1 or 2, wherein, The drying temperature is 20-60°C and the time is 10-240 min. The polar solvent is selected from one or more of diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, dichloromethane, trichloromethane, carbon tetrachloride, tetrahydrofuran and phthalate esters; 4. The regeneration method according to any one of claims 1 to 3, wherein Preferably, the polar solvent is a mixed solvent composed of ethers and halogenated alkanes, wherein the volume ratio of the ethers to the halogenated alkanes is 1-5:

1. Preferably, the polar solvent is a mixed solvent composed of ethers, tetrahydrofuran and esters, wherein the volume ratio of the ethers to the tetrahydrofuran to the esters is 1-5:1-5:

1. The volume ratio of the dry silica gel to the polar solvent is 1:1-10, preferably 1:2-5.

5. The regeneration method according to any one of claims 1 to 4, wherein The contacting conditions include a temperature of 20-60°C, a pressure of 0.03-0.1 MPa and a time of 10 min-120 min. The decolorization method comprises the following steps:

6. A method for decolorizing a rubber polymer solution, characterized by, The rubber polymer solution is mixed with silica gel to decolorize; The adsorbed silica gel is separated from the rubber polymer solution; The adsorbed silica gel is regenerated by the regeneration method of any one of claims 1-5. The rubber polymer solution is selected from one or more of lithium-based rubber polymers, nickel-based rubber polymers, cobalt-based rubber polymers and rare earth-based rubber polymers.

7. The decolorizing method according to claim 6, wherein, Before the rubber polymer solution is mixed with silica gel, the rubber polymer solution is diluted; 8. The decolorizing method according to claim 6 or 7, wherein, Preferably, the solvent used for dilution is one or a mixture of two or more of hexane, cyclohexane and heptane; the concentration of the rubber polymer in the diluted solution is 0.5-20 wt%. Preferably, the silica gel is added in an amount of 5-20 wt% of the total mass of the diluted rubber polymer solution. Before the rubber polymer solution is mixed with silica gel, the silica gel is soaked, washed and dried with a solvent; 9. The decolorization method according to any one of claims 6 to 8, wherein, Preferably, the solvent is one or a mixture of two or more of hexane, cyclohexane and heptane. The separation is performed by a funnel with a sand core.

10. The decolorization method according to any one of claims 6 to 9, wherein ​

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