Method for continuously dechlorinating degraded sulfolane and device for continuously dechlorinating degraded sulfolane

Abstract

The invention relates to the technical field of degraded sulfolane treatment, and discloses a degraded sulfolane continuous dechlorination method and a degraded sulfolane continuous dechlorination device, the method comprises the following steps: sending degraded sulfolane into a purification reactor for purification; wherein in the material flow direction, a first resin bed layer and a second resin bed layer are sequentially arranged in the purification treatment reactor, the first resin bed layer is filled with alkalescent anion resin, and the filling density of the first resin bed layer is 0.5-0.9 g / mL; the second resin bed layer is filled with strongly basic anion resin, and the filling density of the second resin bed layer is 0.55-1g / mL; when the pH value of the degraded sulfolane is less than or equal to 7, enabling the degraded sulfolane to continuously flow through the first resin bed layer and the second resin bed layer; when the pH value of the degraded sulfolane is larger than 7, the degraded sulfolane flows through the second resin bed layer, by means of the method, the treatment rate of the degraded sulfolane can be increased, and the chlorine ion content of the treated sulfolane is low.

Description

Technical Field

[0001] This invention relates to the field of degraded sulfolane treatment technology, specifically to a method and apparatus for continuous dechlorination of degraded sulfolane. Background Technology

[0002] Sulfolane is one of the ideal solvents for extracting aromatics from reformed and cracked gasoline, and it is widely used in the petrochemical industry. After a period of operation, the solvent in the extraction unit deteriorates, causing the solvent in the extraction system to darken in color, the pH value to drop, severe corrosion of the equipment, and scale buildup that clogs the unit. This seriously affects the normal operation of the aromatics extraction unit and increases solvent loss.

[0003] Dong Zhi et al., in their paper "Summary of Industrial Application of Degraded Sulfolane Regeneration Technology" (Refining Technology and Engineering, 2021, 51(8):9-12), disclosed a technology for treating degraded sulfolane using ion exchange. This technology involves a reversible ion exchange transfer reaction at the interface between the solid resin and the solution, removing acidic components and chloride ions from the solvent. This significantly improves the quality of the sulfolane solvent in the aromatic hydrocarbon extraction system, resulting in a significant increase in the pH value and a significant decrease in the chloride content. Li Lin et al., in their paper "Application of Online Purification Technology for Sulfolane Solvent in Aromatic Hydrocarbon Extraction Units" (China & Foreign Energy, 2022, 27(4):78-82), used a combination of adsorption filtration and ion exchange to remove degraded substances from the sulfolane solvent, thereby regenerating the solvent. The ion exchange uses a composite ion exchange resin, which contains both special resin groups for removing acidic degradation products of sulfolane and groups for efficiently removing chloride ions. The acidic substances, such as sulfonic acid, produced by the deterioration of the sulfolane solvent replace the original ions on the resin and are retained by the resin, thus removing these acidic substances from the sulfolane. CN115672410A describes a regeneration system and method for regenerating sulfolane. The regeneration system includes a first resin exchange column and a second resin exchange column connected in parallel, which operate alternately to perform ion exchange on the pretreated sulfolane flowing through, regenerating it to obtain regenerated sulfolane. However, this does not fundamentally extend the regeneration cycle of the exchange resin columns. Regenerating sulfolane using only macroporous weak-base anion exchange resin results in poor dechlorination at higher pH values. CN101284826A describes a tank connected in series containing a sulfonic acid-based polystyrene macroporous strong acid cation exchange resin and an ammonium-based polystyrene macroporous strong-base anion exchange resin. Under pressure, the material flows sequentially through the cation exchange resin tank and the anion exchange resin tank, resulting in the decolorized finished product. However, the sulfolane flows slowly through the resin columns, limiting the throughput per unit time. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems of slow purification speed and unsatisfactory dechlorination effect of existing technologies for degraded sulfolane, and to provide a method and apparatus for continuous dechlorination of degraded sulfolane. This method has the characteristics of high chlorine removal rate and good deep dechlorination effect.

[0005] To achieve the above objectives, the present invention provides a method for continuous dechlorination of degraded sulfolane, the method comprising: feeding the degraded sulfolane into a purification reactor for purification;

[0006] Along the flow direction, the purification reactor is provided with a first resin bed and a second resin bed in sequence. The first resin bed is filled with a weakly basic anion exchange resin with a packing density of 0.5-0.9 g / mL. The second resin bed is filled with a strongly basic anion exchange resin with a packing density of 0.55-1 g / mL.

[0007] When the pH of the degraded sulfolane is ≤7, the degraded sulfolane is continuously flowed through the first resin bed and the second resin bed.

[0008] When the pH of the degraded sulfolane is greater than 7, the degraded sulfolane is allowed to flow through the second resin bed.

[0009] A second aspect of the present invention provides an apparatus for continuous dechlorination of degraded sulfolane, the apparatus comprising: a degraded sulfolane supply unit 5, a pH detector 3, and a purification reactor connected sequentially along a material flow method;

[0010] The pH detector is used to measure the pH value of the degraded sulfolane from the degraded sulfolane supply unit.

[0011] Along the flow direction, the purification reactor is sequentially provided with a first resin bed 1 and a second resin bed 2. The first resin bed 1 is filled with a weakly basic anion exchange resin, and the second resin bed 2 is filled with a strongly basic anion exchange resin.

[0012] The top of the first resin bed 1 and the second resin bed 2 are respectively provided with sealing devices 4, which are used to compact the resin filled in the first resin bed and the second resin bed.

[0013] The degraded sulfolane supply unit is connected to the inlets of the first resin bed 1 and the second resin bed 2 via pipelines, and the connection of the pipelines is controlled by at least one control valve installed on the pipelines.

[0014] The above technical solution selectively passes degraded sulfolane through resin layers packed with different types of anion exchange resins based on the pH value of the sulfolane. By controlling the packing density of the anion exchange resins in the two resin layers, the purification treatment route can be flexibly adjusted for different degraded sulfolane raw materials. The operation is simple, and the chloride ion content of the treated sulfolane can be less than or equal to 1 mg / L, with a chloride removal rate of ≥90%. Furthermore, it can improve the treatment rate of degraded sulfolane and achieve a high processing capacity per unit time. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a device for continuous dechlorination of degraded sulfolane in some embodiments of the present invention;

[0016] Figure 2 yes Figure 1 A schematic diagram of the middle sealing device.

[0017] Explanation of reference numerals in the attached figures

[0018] 1. First resin layer; 2. Second resin layer; 3. pH detector

[0019] 4. Sealing device; 5. Deteriorated sulfolane supply unit

[0020] 6. Purification sulfolane outlet 41. Sealing cap 42. Spring

[0021] 43 Wire mesh 44 Sealing ring 45 Flow guide groove

[0022] 46 End Caps Detailed Implementation

[0023] 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.

[0024] The first aspect of the present invention provides a method for continuous dechlorination of degraded sulfolane, the method comprising: feeding the degraded sulfolane into a purification reactor for purification;

[0025] Along the flow direction, the purification reactor is provided with a first resin bed and a second resin bed in sequence. The first resin bed is filled with a weakly basic anion exchange resin with a packing density of 0.5-0.9 g / mL. The second resin bed is filled with a strongly basic anion exchange resin with a packing density of 0.55-1 g / mL.

[0026] When the pH of the degraded sulfolane is ≤7, the degraded sulfolane is continuously flowed through the first resin bed and the second resin bed.

[0027] When the pH of the degraded sulfolane is greater than 7, the degraded sulfolane is allowed to flow through the second resin bed.

[0028] In this invention, the degraded sulfolane is selectively passed through resin layers packed with different types of anion exchange resins according to its pH value. By controlling the packing density of the anion exchange resins in the two resin layers, the purification treatment route can be flexibly adjusted for different degraded sulfolane raw materials. The operation is simple, and the chloride ion content of the treated sulfolane can be less than or equal to 1 mg / L, with a chloride removal rate of ≥90%. Furthermore, it can improve the treatment rate of degraded sulfolane and achieve a high processing capacity per unit time.

[0029] In this invention, the packing density refers to the wet apparent density of the resin, which is determined in accordance with GB-T8330-1987.

[0030] According to some preferred embodiments of the present invention, the packing density of the first resin bed is 0.6-0.8 g / mL.

[0031] According to some preferred embodiments of the present invention, the packing density of the second resin bed is 0.65-0.9 g / mL.

[0032] In this invention, the terms "weakly basic anion exchange resin" and "strongly basic anion exchange resin" have conventional definitions in the art and are distinguished based on the different anion groups they contain. Weakly basic anion exchange resins contain weakly basic groups, such as primary amine groups (also known as primary amino groups) -NH2, secondary amine groups (secondary amino groups) -NHR, or tertiary amine groups (tertiary amino groups) -NR2, which can dissociate into OH groups in water. - It exhibits weak alkalinity. Strongly alkaline anion exchange resins primarily contain stronger reactive groups, such as quaternary ammonium-N... + R3.

[0033] Both the weakly basic anion exchange resin and the strongly basic anion exchange resin can be commercially available products, and the present invention does not have any particular limitations on this.

[0034] According to some preferred embodiments of the present invention, the weakly basic ion exchange resin is selected from at least one of D301, D315, IRA68, and IRA93.

[0035] According to some preferred embodiments of the present invention, the strongly basic anion exchange resin is selected from at least one of D296, D352, IRA900, and IRA401.

[0036] According to some preferred embodiments of the present invention, the volume ratio of the weakly basic anion exchange resin packed in the first resin bed to the strongly basic anion exchange resin packed in the second resin bed is (1-10):1, for example, it can be a specific volume ratio or any range between 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, etc. Preferably, the volume ratio of the weakly basic anion exchange resin packed in the first resin bed to the strongly basic anion exchange resin packed in the second resin bed is (1-5):1. In the present invention, the above volume ratio refers to the volume ratio after packing, that is, the volume ratio after compaction.

[0037] According to the present invention, in order to further extend the continuous operation cycle of the purification treatment, preferably, the second resin bed is also filled with a weakly basic anion exchange resin. In the above preferred embodiment, the type of weakly basic anion exchange resin in the second resin bed can be the same as or different from the type of weakly basic anion exchange resin in the first resin bed. The present invention does not particularly limit the filling method of the weakly basic anion exchange resin and the strong basic anion exchange resin in the second resin bed; it can be mixed filling or layered filling, preferably uniformly mixed filling, and satisfying the above-mentioned bed filling density.

[0038] According to some preferred embodiments of the present invention, in the second resin bed, the volume ratio of the weakly basic anion exchange resin to the strongly basic anion exchange resin is (0.1-2):1, for example, it can be a specific volume ratio or any range between two such ratios, such as 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.2:1, 1.4:1, 1.6:1, 1.8:1, 2:1, etc. Preferably, in the second resin bed, the volume ratio of the weakly basic anion exchange resin to the strongly basic anion exchange resin is (0.1-0.5):1.

[0039] This invention does not impose any particular limitations on the specific flow conditions of the degraded sulfolane in the purification reactor. As long as the above-mentioned selective treatment method is met, the purification effect of the degraded sulfolane can be improved. In order to further improve the dechlorination efficiency and extend the continuous operation cycle, preferably, when the pH of the degraded sulfolane is ≤7, the linear flow rate of the degraded sulfolane is controlled at 0.5-8 m / h, preferably 0.8-6 m / h.

[0040] When the pH of the degraded sulfolane is ≤7, the degraded sulfolane can flow through the first and second resin beds at any temperature; the contact temperatures of the two resin beds can be the same or different. Preferably, the temperature of the first resin bed is 40-70°C, more preferably 40-60°C. Preferably, the temperature of the second resin bed is 30-60°C, more preferably 30-55°C.

[0041] According to some preferred embodiments of the present invention, when the pH of the degraded sulfolane is >7, the linear flow rate of the degraded sulfolane is controlled to be 0.5-8 m / h, preferably 0.8-6 m / h.

[0042] Preferably, the temperature of the second resin bed is 40-60°C.

[0043] According to the present invention, the method further includes: regenerating the anion exchange resin packed in the purification reactor. Those skilled in the art can choose to perform regeneration at any time according to actual needs.

[0044] According to some preferred embodiments of the present invention, when the chlorine content in the effluent stream from the purification reactor is higher than 1 mg / L, the feed of deteriorated sulfolane is stopped, and the regenerated solution is sent into the purification reactor for regeneration treatment.

[0045] The present invention has a wide range of options for the regeneration solution, and can use conventional regeneration solutions in the art. Preferably, the regeneration solution is an alkaline solution, and more preferably an aqueous solution of sodium hydroxide and / or potassium hydroxide.

[0046] Preferably, the concentration of the regeneration solution is 1-5 wt%, more preferably 2-3.5 wt%.

[0047] According to some preferred embodiments of the present invention, the linear flow rate of the regenerated solution fed into the purification reactor is 4-16 m / h, preferably 4-14 m / h.

[0048] According to the present invention, preferably, the temperature of the regeneration process is 10-30°C.

[0049] According to some preferred embodiments of the present invention, the ratio of the volume of the regenerated solution to the total volume of the resin in the purification reactor is (6-20):1, preferably (8-16):1.

[0050] According to some preferred embodiments of the present invention, the regeneration process further includes: first injecting an eluent into a purification reactor, and then sending the regeneration solution into the purification reactor.

[0051] The eluent is used to remove any residual deposited impurities (such as ferric hydroxide) that may remain in the anion exchange resin. Preferably, the eluent is an acid solution, preferably an aqueous solution of an inorganic acid, such as an aqueous solution of nitric acid and / or sulfuric acid.

[0052] Preferably, the concentration of the acid solution is 1-5 wt%, more preferably 2-3.5 wt%.

[0053] According to some preferred embodiments of the present invention, the linear flow rate of the eluent fed into the purification reactor is 4-16 m / h, preferably 4-14 m / h.

[0054] According to some preferred embodiments of the present invention, the volume ratio of the eluent to the total volume of the resin in the purification reactor is (1-20):1, preferably (8-16):1.

[0055] The present invention does not have any particular limitation on the washing method, and water can be used for rinsing.

[0056] A second aspect of the present invention provides an apparatus for continuous dechlorination of degraded sulfolane, the apparatus comprising: a degraded sulfolane supply unit 5, a pH detector 3, and a purification reactor connected sequentially along a material flow method;

[0057] The pH detector is used to measure the pH value of the degraded sulfolane from the degraded sulfolane supply unit.

[0058] Along the flow direction, the purification reactor is sequentially provided with a first resin bed 1 and a second resin bed 2. The first resin bed 1 is filled with a weakly basic anion exchange resin, and the second resin bed 2 is filled with a strongly basic anion exchange resin.

[0059] The top of the first resin bed 1 and the second resin bed 2 are respectively provided with sealing devices 4, which are used to compact the resin filled in the first resin bed and the second resin bed.

[0060] The degraded sulfolane supply unit is connected to the inlets of the first resin bed 1 and the second resin bed 2 via pipelines, and the connection of the pipelines is controlled by at least one control valve installed on the pipelines.

[0061] In this invention, any conventional sealing device in the art can be selected, as long as it can achieve the purpose of compacting the resin packed in the first and second resin beds. Preferably, the sealing device is an elastic sealing device.

[0062] According to some preferred embodiments of the present invention, such as Figure 2 As shown, the elastic sealing device includes an end cap 46, a guide groove 45, a sealing cap 41, and a wire mesh 43. A spring 42 is provided between the end cap and the sealing cap. The sealing cap 41 is in contact with the spring 42, and the spring 42 is movably connected to the end cap 46, allowing the sealing cap to move up and down within the purification reactor. Preferably, the sealing device further includes a sealing ring 44 nested outside the sealing cap.

[0063] In this invention, the pH detector can be selected from any online pH meter, as long as it can measure the pH value of the deteriorated sulfolane in the main feed line online.

[0064] The present invention will be described in detail below through embodiments.

[0065] Example 1

[0066] Adopting such Figure 1 The deteriorated sulfolane continuous dechlorination device shown is, for example... Figure 1 As shown, the apparatus includes: a degraded sulfolane supply unit, a pH detector, and a purification reactor, sequentially connected along the material flow path; a first resin bed 1 and a second resin bed 2 are sequentially arranged in the purification reactor along the material flow direction, and the first resin bed 1 and the second resin bed 2 are connected by a pipeline equipped with a three-way valve. The first resin bed 1 is filled with a weakly basic anion exchange resin D301; the second resin bed 2 is mixed with a strongly basic anion exchange resin D296 and a weakly basic anion exchange resin D301. The volume ratio of the weakly basic anion exchange resin D301 in the first resin bed to the strongly basic anion exchange resin D296 and the weakly basic anion exchange resin D301 in the second resin bed is 1:0.9:0.1. The packing density of the first resin bed is 0.8 g / mL, and the packing density of the second resin bed is 0.85 g / mL.

[0067] The pH detector is an online pH meter, PHG-21D, from Shanghai Instrument & Electronics Scientific Instruments Co., Ltd.

[0068] The pH value of the degraded sulfolane was measured to be 3.5, and the chloride ion content was 160 mg / L. The control valve on the pipeline was adjusted to allow the degraded sulfolane to enter the purification reactor from the top. The degraded sulfolane flowed sequentially through the first and second resin beds at a linear flow rate of 6 m / h. The temperature of the first resin bed was controlled at 44℃, and the temperature of the second resin bed at 43℃.

[0069] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 0.3 mg / L.

[0070] After 12 hours of continuous operation, the chlorine content in the effluent from the purification reactor exceeded 1 mg / L. The feed of degraded sulfolane was stopped, and the sulfolane material was removed. First, an eluent (3 wt% H₂SO₄ solution) was fed into the purification reactor at a linear flow rate of 10 m / h and a temperature of 25°C. The volume ratio of the eluent to the total volume of anion exchange resin in the purification reactor was 1:1. After washing with water, a regeneration solution (3 wt% NaOH solution) was fed into the purification reactor at a linear flow rate of 10 m / h and a temperature of 25°C. The volume ratio of the regeneration solution to the total volume of anion exchange resin in the purification reactor was 8:1.

[0071] Then repeat the above dechlorination process of sulfolane.

[0072] Example 2

[0073] Adopting such Figure 1 The deteriorated sulfolane continuous dechlorination device shown is, for example... Figure 1 As shown, the apparatus includes: a degraded sulfolane supply unit, a pH detector, and a purification reactor, sequentially connected along the material flow path; a first resin bed 1 and a second resin bed 2 are sequentially arranged in the purification reactor along the material flow direction, and the first resin bed 1 and the second resin bed 2 are connected by a pipeline equipped with a three-way valve. The first resin bed 1 is filled with a weakly basic anion exchange resin D315; the second resin bed 2 is mixed with a strongly basic anion exchange resin D352 and a weakly basic anion exchange resin D315. The volume ratio of the weakly basic anion exchange resin D315 in the first resin bed to the strongly basic anion exchange resin D352 and the weakly basic anion exchange resin D315 in the second resin bed is 1:0.8:0.2. The packing density of the first resin bed is 0.8 g / mL, and the packing density of the second resin bed is 0.83 g / mL.

[0074] The pH detector is an online pH meter, PHG-21D, from Shanghai Instrument & Electronics Scientific Instruments Co., Ltd.

[0075] The pH value of the degraded sulfolane was measured to be 3.5, and the chloride ion content was 200 mg / L. The control valve on the pipeline was adjusted to allow the degraded sulfolane to enter the purification reactor from the top. The degraded sulfolane flowed sequentially through the first and second resin beds at a linear flow rate of 5 m / h. The temperature of the first resin bed was controlled at 49°C, and the temperature of the second resin bed at 40°C.

[0076] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 0.4 mg / L.

[0077] Example 3

[0078] The purification treatment device of Example 1 was used.

[0079] The pH value of the degraded sulfolane was measured to be 8.5, and the chloride ion content was 10 mg / L. The control valve on the pipeline was adjusted to allow the degraded sulfolane to enter the purification reactor from the middle, flowing through the second resin bed at a linear flow rate of 4 m / h. The temperature of the second resin bed was controlled at 46℃.

[0080] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 0.5 mg / L.

[0081] Example 4

[0082] The method is the same as in Example 1, except that the packing density of the first resin bed is 0.58 g / mL and the packing density of the second resin bed is 0.62 g / mL.

[0083] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 0.6 mg / L.

[0084] Example 5

[0085] The method is the same as in Example 1, except that the first resin bed is filled with a weakly basic anion exchange resin D301, and the second resin bed is filled with a strongly basic anion exchange resin D296; the volume ratio of the resin in the first resin bed to the second resin bed is 1:1.

[0086] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 0.5 mg / L.

[0087] Example 6

[0088] The method is the same as in Example 1, except that the volume ratio of the weakly basic anion exchange resin D301 in the first resin bed, the strongly basic anion exchange resin D296 in the second resin bed, and the weakly basic anion exchange resin D301 is 1:0.3:0.7.

[0089] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 1 mg / L.

[0090] Example 7

[0091] The method is the same as in Example 1, except that the degraded sulfolane is sequentially flowed through the first and second resin beds at a linear flow rate of 6 m / h. The temperature of the first resin bed is controlled at 40°C, and the temperature of the second resin bed is controlled at 60°C.

[0092] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 1 mg / L.

[0093] Comparative Example 1

[0094] The method is the same as in Example 6, except that the purification device does not include an elastic sealing device. The packing density of the first resin bed is 0.48 g / mL, and the packing density of the second resin bed is 0.53 g / mL.

[0095] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 1.3 mg / L.

[0096] Comparative Example 2

[0097] The method is the same as in Example 5, except that the first resin bed is filled with a strong basic anion exchange resin D296, and the second resin bed is filled with a weak basic anion exchange resin D301.

[0098] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 2.5 mg / L.

[0099] Comparative Example 3

[0100] The method is the same as in Example 1, except that the control valve on the pipeline is adjusted to allow the degraded sulfolane to enter the purification reactor from the middle and be directly fed into the second resin bed.

[0101] The purified product was collected from the purification sulfolane outlet 6 at the bottom of the purification processor, and the chloride ion content was measured to be 3.3 mg / L.

[0102] 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 continuous dechlorination of degraded sulfolane, characterized in that, The method includes: feeding degraded sulfolane into a purification reactor for purification; Along the flow direction, the purification reactor is provided with a first resin bed and a second resin bed in sequence. The first resin bed is filled with a weakly basic anion exchange resin with a filling density of 0.5-0.9 g / mL. The second resin bed is filled with a strongly basic anion exchange resin with a filling density of 0.55-1 g / mL. When the pH of the degraded sulfolane is ≤7, the degraded sulfolane is continuously flowed through the first resin bed and the second resin bed. When the pH of the degraded sulfolane is greater than 7, the degraded sulfolane is allowed to flow through the second resin bed.

2. The method according to claim 1, wherein, The packing density of the first resin bed is 0.6-0.8 g / mL; And / or, the packing density of the second resin bed is 0.65-0.9 g / mL.

3. The method according to claim 1 or 2, wherein, The anionic groups contained in the weakly basic anion exchange resin are selected from at least one of primary amine, secondary amine and tertiary amine groups, preferably at least one of D301, D315, IRA68 and IRA93; Preferably, the anionic group contained in the strongly basic anion exchange resin is a quaternary ammonium group, preferably at least one of D296, D352, IRA900, and IRA401; Preferably, the volume ratio of the weakly basic anion exchange resin packed in the first resin bed to the strongly basic anion exchange resin packed in the second resin bed is (1-10):1, more preferably (1-5):

1.

4. The method according to any one of claims 1-3, wherein, The second resin column is also filled with a weakly basic anion exchange resin. Preferably, in the second resin column, the volume ratio of weakly basic anion exchange resin to strongly basic anion exchange resin is (0.1-2):1, more preferably (0.1-0.5):

1.

5. The method according to any one of claims 1-4, wherein, When the pH of the degraded sulfolane is ≤7, the linear flow rate of the degraded sulfolane is controlled to be 0.5-8 m / h, preferably 0.8-6 m / h; Preferably, the temperature of the first resin bed is 40-70°C, and more preferably 40-60°C; Preferably, the temperature of the second resin bed is 30-60°C, and more preferably 30-55°C.

6. The method according to any one of claims 1-5, wherein, When the pH of the degraded sulfolane is greater than 7, the linear flow rate of the degraded sulfolane is controlled to be 0.5-8 m / h, preferably 0.8-6 m / h; Preferably, the temperature of the second resin bed is 40-60°C.

7. The method according to any one of claims 1-6, wherein, The method further includes: when the chlorine content in the effluent from the purification reactor is higher than 1 mg / L, regenerating the anion exchange resin packed in the purification reactor. Preferably, the regeneration process includes: feeding the regeneration solution into a purification reactor and contacting it with the packed anion exchange resin; Preferably, the regeneration solution is an alkaline solution, preferably an aqueous solution of sodium hydroxide and / or potassium hydroxide; Preferably, the concentration of the regeneration solution is 1-5 wt%, more preferably 2-3.5 wt%. Preferably, the linear flow rate of the regenerated solution fed into the purification reactor is 1-15 m / h, more preferably 1-10 m / h; Preferably, the regeneration treatment temperature is 10-30℃; Preferably, the ratio of the volume of the regenerated solution to the total volume of the resin in the purification reactor is (5-20):1, more preferably (8-15):

1.

8. The method according to claim 7, wherein, The regeneration process further includes: first injecting an eluent into the purification reactor, then washing, and then sending the regeneration solution into the purification reactor; Preferably, the eluent is an acid solution, preferably an aqueous solution of nitric acid and / or sulfuric acid.

9. An apparatus for continuous dechlorination of degraded sulfolane, characterized in that, The device includes: a degraded sulfolane supply unit (5), a pH detector (3), and a purification reactor, which are connected sequentially along the logistics method; The pH detector is used to measure the pH value of the degraded sulfolane from the degraded sulfolane supply unit. Along the flow direction, the purification reactor is sequentially provided with a first resin bed (1) and a second resin bed (2), wherein the first resin bed (1) is filled with a weakly basic anion exchange resin and the second resin bed (2) is filled with a strongly basic anion exchange resin. The first resin bed (1) and the second resin bed (2) are respectively provided with sealing devices (4) for compacting the resin filled in the first resin bed and the second resin bed. The degraded sulfolane supply unit is connected to the inlet of the first resin bed (1) and the second resin bed (2) through pipelines, and the connection of the pipelines is controlled by at least one control valve installed on the pipelines.

10. The apparatus according to claim 9, wherein, The sealing device (4) includes an end cap (46), a guide groove (45), a sealing cap (41), and a wire mesh (43). A spring (42) is provided between the end cap and the sealing cap. The sealing cap (41) is in contact with the spring (42), and the spring (42) is movably connected to the end cap (46), so that the sealing cap moves up and down inside the purification reactor.

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