A method for adsorption separation of cymene oxidation products

Abstract

The invention discloses an adsorption separation method for cymene oxidation products, wherein the cymene oxidation products contain cymene, tertiary peroxide TCHP of cymene and primary peroxide PCHP of cymene, and the adsorption separation method uses the cymene oxidation products as raw materials, adopts a simulated moving adsorption bed to perform adsorption separation on the cymene oxidation products, the stationary phase of the simulated moving adsorption bed is a weakly basic anion exchange resin, and the temperature of the adsorption separation is 15-45° C. The adsorption separation method of the invention can effectively separate TCHP and PCHP, and the obtained TCHP can be used for subsequent acid hydrolysis reaction to prepare a target product of p-methylphenol, and the obtained PCHP can be used for subsequent preparation of byproducts such as cuminaldehyde or cuminol.

Description

Technical Field

[0001] The invention relates to an adsorption separation method for cymene oxidation products. Background Art

[0002] p-Methylphenol is an important chemical raw material and an important raw material for synthesizing fine chemical products such as BHT (2,6-di-tert-butyl-p-cresol), anisaldehyde, and p-hydroxybenzaldehyde. There are two main methods for preparing p-methylphenol, one is the sulfuric acid sulfonation method, and the other is the cymene oxidation method (isopropyltoluene oxidation method). Among them, the cymene oxidation method is a green method for producing p-methylphenol. This method uses cymene as a raw material, and obtains p-methylphenol through a hydroperoxidation reaction and acid hydrolysis of the hydroperoxide product. Compared with the sulfuric acid sulfonation method, this method consumes less acid and alkali and has a cleaner process.

[0003] The reaction route of producing p-methylphenol (p-cresol) by cymene oxidation is as follows:

[0004]

[0005] Among them, cymene oxidation simultaneously produces two peroxides: tertiary peroxide (TCHP) and primary peroxide (PCHP). Tertiary peroxide (TCHP) is hydrolyzed by acid to obtain the target product p-methylphenol. Primary peroxide (PCHP) is decomposed by acid hydrolysis to isopropylphenol and formaldehyde, and formaldehyde will react with the target product p-methylphenol to formaldehyde condensation, thereby reducing its yield.

[0006] To address this problem, the prior art generally involves alkaline hydrolysis of the cymene oxidation product (containing TCHP and PCHP) to destroy PCHP and generate cuminaldehyde. Cumyl alcohol The cymene oxidation product is then concentrated and acid-hydrolyzed to obtain a mixture of p-methylphenol, cuminaldehyde and cuminol, which is then separated by distillation to obtain the target product p-methylphenol. However, in this process route, the byproducts cuminaldehyde and cuminol generated by PCHP are mixed with the target product p-methylphenol in the acid hydrolysis solution, and the acid hydrolysis solution has complex components, which increases the difficulty of separating the target product p-methylphenol on the one hand, and makes it difficult to recycle the byproducts cuminaldehyde and cuminol on the other hand, resulting in a partial waste of resources. Summary of the invention

[0007] In view of the shortcomings and deficiencies of the prior art, the present invention provides an adsorption separation method for cymene oxidation products, which can effectively separate tertiary peroxide TCHP and primary peroxide PCHP in cymene oxidation products, and the separated tertiary peroxide TCHP can be subjected to acid hydrolysis to obtain p-methylphenol which is easy to separate and purify, while the separated primary peroxide PCHP has a high purity and can be used to prepare cuminaldehyde and cuminol.

[0008] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0009] The invention discloses an adsorption separation method for cymene oxidation products, wherein the cymene oxidation products contain cymene, tertiary peroxide TCHP of cymene and primary peroxide PCHP of cymene. The adsorption separation method uses the cymene oxidation products as raw materials and adopts a simulated moving adsorption bed to perform adsorption separation on the cymene oxidation products. The stationary phase of the simulated moving adsorption bed is a weakly basic anion exchange resin. The temperature of the adsorption separation is 15-45°C.

[0010] The cymene oxidation product of the present invention refers to a mixture system obtained by subjecting cymene to a hydroperoxidation reaction.

[0011] In some embodiments of the present invention, the weakly basic anion exchange resin is selected from a combination of one or more of Amberlyst A21, IRA96 RF, Amberlite FPA51, Amberlite FPA53, Amberlite FPA54, Amberlite FPA55, Amberlite IRA743 and Amberlite PWA7.

[0012] In some embodiments of the present invention, the mobile phase of the simulated mobile adsorption bed is selected from a combination of one or more of methyl isobutyl ketone MIBK, cymene PCY and acetone. Pure cymene (isopropyl toluene), as an aromatic hydrocarbon, has a good solvent effect on organic matter and is also a solvent, which can be used as the mobile phase of the present invention.

[0013] In some embodiments of the present invention, the simulated moving adsorption bed is selected from a semi-continuous simulated moving adsorption bed or a fully continuous sequential simulated moving adsorption bed, wherein the fully continuous sequential simulated moving adsorption bed is more conducive to industrialization.

[0014] In some embodiments of the present invention, the cymene oxidation product includes 10-65% of tertiary peroxide TCHP of cymene, 5-15% of primary peroxide PCHP of cymene and 20-80% of cymene in terms of mass percentage, wherein the cymene is the residual cymene raw material that has not undergone oxidation reaction.

[0015] In some embodiments of the present invention, the cymene oxidation product further comprises 0.5-5.0% trimethylbenzyl alcohol, 0.1-1.0% p-methylacetophenone, 0.1-1.0% cuminaldehyde and 0.1-1.0% cuminol in terms of mass percentage. The above substances are small amounts of byproducts produced by the hydroperoxidation of cymene.

[0016] The inventors have found through research that the adsorption capacity of the weakly basic anion exchange resin for the primary peroxide PCHP of cymene is significantly stronger than that for the tertiary peroxide TCHP of cymene, and when adsorbed at a relatively low temperature, the weakly basic anion exchange resin has a relatively weak alkalinity, and the weak alkalinity and low temperature are not sufficient to significantly decompose the primary peroxide PCHP of cymene. Therefore, the PCHP adsorbed by the weakly basic anion exchange resin hardly decomposes, and then the weakly basic anion exchange resin can be used as the stationary phase of the simulated mobile adsorption bed, and a suitable mobile phase can be used to efficiently separate PCHP and TCHP, and after separation, PCHP and TCHP with high purity can be obtained respectively. The obtained TCHP can be used for the subsequent acidolysis reaction to prepare the target product of p-methylphenol, and the obtained PCHP can be used for the subsequent preparation of cuminaldehyde or cuminol, which avoids the mixing of cuminaldehyde or cuminol obtained by the alkaline hydrolysis of PCHP in the prior art in TCHP, resulting in the presence of cuminaldehyde or cuminol in p-methylphenol after the subsequent acidolysis reaction, resulting in the difficulty in separating p-methylphenol.

[0017] In some embodiments of the present invention, the simulated moving adsorption bed is divided into four regions, namely:

[0018] Zone I: from the mobile phase input point to the PCHP extraction point of the primary peroxide of cymene;

[0019] Zone II: from the PCHP extraction point of the primary peroxide of cymene to the feeding point of the cymene oxidation product;

[0020] Zone III: From the feed point of cymene oxidation product to the extraction point of TCHP of tertiary peroxide of cymene;

[0021] Zone IV: From the extraction point of TCHP, the tertiary peroxide of cymene, to the input point of the mobile phase.

[0022] The functions of the above-mentioned areas are as follows:

[0023] Zone I: The stationary phase weakly basic anion exchange resin adsorbed with PCHP is desorbed by the mobile phase in this zone to obtain a mobile phase solution of PCHP without TCHP, and the stationary phase resin returns to zone IV;

[0024] Zone II: Since TCHP has a weaker adsorption on the stationary phase resin, it is easier to be eluted by the mobile phase, while PCHP is more difficult to be eluted. After refining in Zone II, the stationary phase resin contains almost only PCHP and is sent to Zone I for elution; the eluent of the mobile phase contains TCHP and PCHP, which is mixed with the feed of cymene oxidation product and then enters Zone III.

[0025] Zone III: TCHP and PCHP in the raw material of cymene oxidation product and the mobile phase eluent are adsorbed in this zone, PCHP is almost completely adsorbed by the stationary phase resin, while a small amount of TCHP is adsorbed by the stationary phase resin. A mobile phase solution of TCHP and cymene PCY containing almost no PCHP is obtained at the outlet of this zone, and the stationary phase resin phase adsorbed with TCHP and PCHP is sent to Zone II for refining;

[0026] Zone IV: The stationary phase resin adsorbs TCHP in this zone to obtain clean cymene PCY and returns to zone I. The cymene PCY can serve as part of the mobile phase, which can save part of the mobile phase; the stationary phase resin enters zone III to adsorb PCHP and TCHP.

[0027] In some embodiments of the present invention, the simulated moving adsorption bed is formed by 4 to 24 identical chromatography columns connected in series, the zone I is formed by 0.17*N total to 0.25*N total identical chromatography columns connected in series, the zone II is formed by 0.3*N total to 0.45*N total identical chromatography columns connected in series, the zone III is formed by 0.23*N total to 0.35*N total identical chromatography columns connected in series, and the zone IV is formed by 0.1*N total to 0.15*N total identical chromatography columns connected in series, wherein N total is the total number of chromatography columns of the simulated moving adsorption bed.

[0028] In some embodiments of the present invention, the ratio of the flow rate of the mobile phase to the feed flow rate of the cymene oxidation product is 0.4-5.0:1.

[0029] In some embodiments of the present invention, the ratio of the withdrawal flow rate of the primary peroxide PCHP of cymene to the feed flow rate of the cymene oxidation product is 0.2-3.5:1.

[0030] In some embodiments of the present invention, the ratio of the withdrawal flow rate of the tertiary peroxide TCHP of cymene to the feed flow rate of the cymene oxidation product is 1.2-2.5:1.

[0031] The cymene oxidation product and the mobile phase are feeds, the primary peroxide PCHP of cymene and the tertiary peroxide TCHP of cymene are discharges, and the total feed rate is equal to the total discharge rate. Therefore, the sum of the flow rates of the cymene oxidation product and the mobile phase is equal to the sum of the flow rates of the primary peroxide PCHP of cymene and the tertiary peroxide TCHP of cymene.

[0032] In some embodiments of the present invention, the produced liquid obtained from the production point of the primary peroxide PCHP of cymene contains the primary peroxide PCHP of cymene and the tertiary peroxide TCHP of cymene, and the primary peroxide PCHP of cymene accounts for 55.0%-99.0% of the total mass of the two, preferably 65.0%-99.0%, more preferably 75.0%-99.0%, further preferably 80.0%-99.0%, and even more preferably 90.0%-99.0%.

[0033] In some embodiments of the present invention, the produced liquid obtained from the tertiary peroxide TCHP production point of cymene contains primary peroxide PCHP of cymene and tertiary peroxide TCHP of cymene, and the tertiary peroxide TCHP of cymene accounts for 93.0%-99.9% of the total mass of the two, preferably 97.0%-99.9%.

[0034] In some embodiments of the present invention, the mobile phase is methyl isobutyl ketone, and the ratio of the flow rate of the mobile phase to the feed flow rate of the cymene oxidation product is 0.5-1.5:1.

[0035] In some embodiments of the present invention, the mobile phase is cymene, and the ratio of the flow rate of the mobile phase to the feed flow rate of the cymene oxidation product is 3-5:1.

[0036] In some embodiments of the present invention, the recovery rate of the tertiary peroxide TCHP of the cymene by the adsorption separation method is 90.0%-99.9%, preferably 92.0%-99.9%.

[0037] In some embodiments of the present invention, the recovery rate of the primary peroxide PCHP of cymene by the adsorption separation method is 60.0%-99.5%, preferably 90.0%-99.5% or more.

[0038] The present invention further provides a method for producing p-methylphenol, which comprises the following steps: 1) using cymene as a raw material to perform a hydroperoxidation reaction to obtain a cymene oxidation product; 2) using the above-mentioned adsorption separation method for cymene oxidation products to perform adsorption separation on the cymene oxidation product to obtain tertiary peroxide TCHP of cymene; 3) acid hydrolyzing the tertiary peroxide TCHP of cymene to obtain the p-methylphenol.

[0039] Compared with the prior art, the present invention has the following advantages:

[0040] The invention adopts weakly basic anion exchange resin as the stationary phase of the simulated mobile adsorption bed, and by controlling the adsorption separation temperature to be relatively low at 15-45° C., the simulated mobile adsorption bed can effectively separate the tertiary peroxide TCHP and the primary peroxide PCHP in the cymene oxidation product, and obtains PCHP and TCHP with high purity respectively after separation. The obtained TCHP can be used for the subsequent acid hydrolysis reaction to prepare the target product of p-methylphenol, and the obtained PCHP can be used for the subsequent preparation of cuminaldehyde or cuminol, thereby avoiding the mixing of cuminaldehyde or cuminol obtained by alkaline hydrolysis of PCHP in TCHP in the prior art, resulting in p-methylphenol containing cuminaldehyde or cuminol after the subsequent acid hydrolysis reaction, and making it difficult to separate p-methylphenol.

[0041] The adsorption separation method of the present invention can achieve a high recovery rate of the tertiary peroxide TCHP of cymene and the primary peroxide PCHP of cymene.

[0042] The adsorption separation method of the present invention can achieve that in the produced liquid obtained from the TCHP production point of the tertiary peroxide of cymene (i.e., the TCHP-rich phase), TCHP accounts for more than 97.0% of the total mass of TCHP and PCHP; in the produced liquid obtained from the PCHP production point of the primary peroxide of cymene (i.e., the PCHP-rich phase), PCHP accounts for more than 93.0% of the total mass of PCHP and TCHP; that is, the separation effect of the two is significant. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The separation schematic diagram of the simulated moving adsorption bed of the present invention is shown in the figure, taking methyl isobutyl ketone MIBK as the mobile phase, wherein PCY is cymene, TCHP is the tertiary peroxide of cymene, and PCHP is the primary peroxide of cymene. DETAILED DESCRIPTION

[0044] The main innovation of the present invention is that a weakly basic anion exchange resin is used as the stationary phase of the simulated mobile adsorption bed, and the adsorption separation temperature is controlled to be relatively low at 25 to 45° C. Since the adsorption capacity of the weakly basic anion exchange resin to the primary peroxide PCHP of cymene is significantly stronger than that to the tertiary peroxide TCHP of cymene, and the peroxide PCHP is prone to decomposition only when the alkalinity is relatively strong and the temperature is relatively high, the use of the weakly basic anion exchange resin and low temperature conditions can, on the one hand, inhibit the decomposition of PCHP, and on the other hand, can utilize the difference in the adsorption capacity of the resin to PCHP and TCHP to effectively separate the two.

[0045] Taking methyl isobutyl ketone MIBK as the mobile phase, the entire separation process of the simulated moving adsorption bed of the present invention is described as follows: Figure 1As shown, after the raw material of cymene oxidation product (containing main components such as PCY, PCHP, TCHP, etc., represented by the abbreviation PCY / PCHP / TCHP) passes through zone III, the PCHP therein combines with the stationary phase resin, and the mobile phase solution of high purity PCY / TCHP flows out from the nodes of zones III and IV; part of the mobile phase solution of PCY / TCHP passes through zone IV, and after the stationary phase resin in zone IV completely adsorbs TCHP, the PCY that contains almost no TCHP returns to zone I to serve as part of the elution solvent; and the stationary phase resin adsorbed with PCHP is washed by MIBK / PCHP in zone II to remove the residual TCHP in the resin; the stationary phase resin that contains almost no TCHP is eluted in zone I by the mobile phase MIBK just fed and the recycled PCY, and high purity PCHP is obtained at the nodes of zones I and II, and PCHP and TCHP can be separated. Among them, the stationary phase resin circulation is a schematic diagram of the countercurrent principle. In actual operation, the inlet and outlet are constantly switched with the column to obtain the effect of countercurrent contact between the stationary phase resin and the mobile phase.

[0046] The present invention is further described below in conjunction with the examples. However, the present invention is not limited to the following examples. The implementation conditions used in the examples can be further adjusted according to the different requirements of specific use, and the implementation conditions not specified are conventional conditions in the industry. The technical features involved in each embodiment of the present invention can be combined with each other as long as they do not conflict with each other.

[0047] Example 1

[0048] This embodiment provides an adsorption separation method for cymene oxidation products, which uses a sequential simulated moving bed for separation. The stationary phase of the sequential simulated moving bed is Amberlyst A21 resin, and the sequential simulated moving bed is formed by 12 identical chromatography columns connected in series, which are divided into 4 regions, namely:

[0049] Zone I: from the mobile phase input point to the PCHP extraction point of the primary peroxide of cymene;

[0050] Zone II: from the PCHP extraction point of the primary peroxide of cymene to the feeding point of the cymene oxidation product;

[0051] Zone III: From the feed point of cymene oxidation product to the extraction point of TCHP of tertiary peroxide of cymene;

[0052] Zone IV: from the extraction point of TCHP, the tertiary peroxide of cymene, to the input point of the mobile phase;

[0053] Among them, the 1st to 3rd chromatography columns are zone I, the 4th to 7th chromatography columns are zone II, the 8th to 10th chromatography columns are zone III, and the 11th to 12th chromatography columns are zone IV.

[0054] The specific steps of adsorption separation are as follows: after the resin is loaded, the mobile phase pump is turned on to replace the solvent in the system with the mobile phase, and then the mobile phase pump, feed pump and circulation pump are turned on at the set flow rate, and the TCHP-enriched phase and PCHP-enriched phase are sampled and analyzed regularly until the results are stable.

[0055] During adsorption separation, process parameters such as feed composition of cymene oxidation product, type of stationary phase resin, type of mobile phase, flow rates of cymene oxidation product, mobile phase, PCHP extraction and TCHP extraction, and adsorption separation temperature are shown in Table 1-2.

[0056] The components and their contents in the produced liquid obtained from the TCHP production point (i.e., TCHP-enriched phase) and the produced liquid obtained from the PCHP production point (i.e., PCHP-enriched phase) were determined by chromatography. The chromatographic conditions were: chromatographic column Kromasil C18, detector DAD, injection volume 10 μL, mobile phase 95% acetonitrile / 5% water, and flow rate 1 mL / min.

[0057] The proportion of TCHP in the TCHP-enriched phase to the total mass of TCHP and PCHP TCHP / (TCHP+PCHP), the proportion of PCHP in the PCHP-enriched phase to the total mass of TCHP and PCHP PCHP / (TCHP+PCHP), and the recoveries of TCHP and PCHP were calculated respectively. The results are shown in Table 3-4.

[0058] Example 2-12

[0059] Example 2-5 provides an adsorption separation method for cymene oxidation products, which adopts a sequential simulated moving bed for separation. The setting of the sequential simulated moving bed and the specific steps of separation are basically the same as those in Example 1, with the only difference being that the operating conditions include the feed composition of the cymene oxidation product, the type of mobile phase, the type of stationary phase resin, the flow rate of some materials, etc., as shown in Table 1-2.

[0060] The corresponding separation results are shown in Table 3-4.

[0061] Comparative Example 1

[0062] This comparative example provides an adsorption separation method for cymene oxidation products, which adopts a sequential simulated moving bed for separation. The setting of the sequential simulated moving bed and the specific steps of separation are basically the same as those in Example 1, with the only difference being that the type of stationary phase resin is replaced with silica gel, as shown in Table 1-2.

[0063] The corresponding separation results are shown in Table 3-4.

[0064] Comparative Example 2

[0065] This comparative example provides an adsorption separation method for cymene oxidation products, which adopts a sequential simulated moving bed for separation. The setting of the sequential simulated moving bed and the specific steps of separation are basically the same as those in Example 1, with the only difference being that the type of stationary phase resin is replaced by a strongly basic anion exchange resin Amberlyst A26OH, as shown in Table 1-2.

[0066] The corresponding separation results are shown in Table 3-4.

[0067] Comparative Example 3

[0068] This comparative example provides an adsorption separation method for cymene oxidation products, which adopts a sequential simulated moving bed for separation. The setting of the sequential simulated moving bed and the specific steps of separation are basically the same as those in Example 1, with the only difference being that the adsorption separation temperature in the operating conditions is increased to 60°C, as shown in Table 1-2.

[0069] The corresponding separation results are shown in Table 3-4.

[0070] Table 1 Raw material composition of each embodiment and comparative example (mass percentage)

[0071]

[0072] Table 2 Operating conditions of each embodiment and comparative example

[0073]

[0074]

[0075] Table 3 Separation results of various embodiments and comparative examples (mass percentage)

[0076]

[0077] Table 4 Separation results of various embodiments and comparative examples (mass percentage)

[0078]

[0079]

[0080] As shown in Tables 3-4, when silica gel is used as the stationary phase of the simulated mobile adsorption bed, TCHP and PCHP cannot be effectively separated. When a strong basic anion exchange resin is used as the stationary phase of the simulated mobile adsorption bed, since the strong basic anion exchange resin can be used as a catalyst for the decomposition of PCHP, it will cause PCHP to be partially decomposed, and the products of PCHP decomposition are cuminaldehyde and cuminol, and water molecules are produced at the same time, resulting in an increase in the content of cuminaldehyde and cuminol in the TCHP-enriched phase, and the presence of a small amount of water, ultimately resulting in a significant decrease in the PCHP recovery rate. When the weakly basic anion exchange resin of the present invention is used as the stationary phase of the simulated mobile adsorption bed, but the adsorption separation temperature is high, the peroxide PCHP will also be partially decomposed, the content of cuminaldehyde and cuminol in the TCHP-enriched phase will also increase, and the PCHP recovery rate will be significantly reduced. In fact, there is competition between the adsorption of PCHP by the alkaline anion exchange resin and the decomposition reaction under the catalysis of the alkaline anion exchange resin. When the alkalinity is stronger and the temperature is higher, PCHP is more inclined to decompose, while when the alkalinity is weaker and the temperature is lower, PCHP is more inclined to be adsorbed and less likely to decompose.

[0081] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

[0082] The endpoints and any values ​​of the ranges disclosed in this article 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 each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

Claims

1. A method for the adsorption separation of cymene oxidation products, wherein the cymene oxidation products contain cymene, tertiary peroxide TCHP of cymene and primary peroxide PCHP of cymene, characterized in that: The adsorption separation method uses cymene oxidation products as raw materials, adopts a simulated moving adsorption bed to perform adsorption separation on the cymene oxidation products, the stationary phase of the simulated moving adsorption bed is a weakly basic anion exchange resin, and the temperature of the adsorption separation is 15-45°C.

2. The method for adsorption separation of cymene oxidation products according to claim 1, characterized in that: The weakly basic anion exchange resin is selected from one or more combinations of Amberlyst A21, IRA96 RF, Amberlite FPA51, Amberlite FPA53, Amberlite FPA54, Amberlite FPA55, Amberlite IRA743 and Amberlite PWA7.

3. The method for adsorption separation of cymene oxidation products according to claim 1, characterized in that: The mobile phase of the simulated moving adsorption bed is selected from a combination of one or more of methyl isobutyl ketone, cymene and acetone; and / or, the simulated moving adsorption bed is selected from a semi-continuous simulated moving adsorption bed or a fully continuous sequential simulated moving adsorption bed.

4. The method for adsorption separation of cymene oxidation products according to claim 1, characterized in that: According to mass percentage, the cymene oxidation product includes 10-65% of tertiary peroxide TCHP of cymene, 5-15% of primary peroxide PCHP of cymene and 20-80% of cymene.

5. The method for adsorption separation of cymene oxidation products according to claim 4, characterized in that: According to mass percentage, the cymene oxidation product also includes 0.5-5.0% trimethylbenzyl alcohol, 0.1-1.0% p-methylacetophenone, 0.1-1.0% cuminaldehyde and 0.1-1.0% cuminol.

6. The method for adsorption separation of cymene oxidation products according to claim 1, characterized in that: The simulated moving adsorption bed is divided into four areas, namely: Zone I: from the mobile phase input point to the PCHP extraction point of the primary peroxide of cymene; Zone II: from the PCHP extraction point of the primary peroxide of cymene to the feeding point of the cymene oxidation product; Zone III: From the feed point of cymene oxidation product to the extraction point of TCHP of tertiary peroxide of cymene; Zone IV: From the extraction point of TCHP, the tertiary peroxide of cymene, to the input point of the mobile phase.

7. The method for adsorption separation of cymene oxidation products according to claim 6, characterized in that: The simulated mobile adsorption bed is formed by connecting 6 to 24 identical chromatography columns in series, the zone I is formed by connecting 0.17*N total to 0.25*N total identical chromatography columns in series, the zone II is formed by connecting 0.3*N total to 0.45*N total identical chromatography columns in series, and the zone III is formed by connecting The zone is formed by connecting the same chromatography columns of 0.23*N total to 0.35*N total in series, and the IV zone is formed by connecting the same chromatography columns of 0.1*N total to 0.15*N The total number of chromatography columns with the same number of roots is connected in series, where N is the total number of chromatography columns of the simulated mobile adsorption bed.

8. The method for adsorption separation of cymene oxidation products according to claim 6, characterized in that: The ratio of the flow rate of the mobile phase to the feed flow rate of the cymene oxidation product is 0.4-5.0:

1.

9. The method for adsorption separation of cymene oxidation products according to claim 6, characterized in that: The ratio of the production flow rate of the primary peroxide PCHP of cymene to the feed flow rate of the oxidation product of cymene is 0.2-3.5:1; and / or the ratio of the production flow rate of the tertiary peroxide TCHP of cymene to the feed flow rate of the oxidation product of cymene is 1.2-2.5:

1.

10. The method for adsorption separation of cymene oxidation products according to claim 6, characterized in that: The produced liquid obtained from the production point of the primary peroxide PCHP of cymene contains the primary peroxide PCHP of cymene and the tertiary peroxide TCHP of cymene, and the primary peroxide PCHP of cymene accounts for 55.0%-99.0% of the total mass of the two; and / or, the produced liquid obtained from the production point of the tertiary peroxide TCHP of cymene contains the primary peroxide PCHP of cymene and the tertiary peroxide TCHP of cymene, and the tertiary peroxide TCHP of cymene accounts for 93.0%-99.9% of the total mass of the two.

11. The method for adsorption separation of cymene oxidation products according to claim 6, characterized in that: The mobile phase is methyl isobutyl ketone, and the ratio of the flow rate of the mobile phase to the feed flow rate of the cymene oxidation product is 0.5-1.5:

1.

12. The method for adsorption separation of cymene oxidation products according to claim 6, characterized in that: The mobile phase is cymene, and the ratio of the flow rate of the mobile phase to the feed flow rate of the cymene oxidation product is 3-5:

1.

13. The method for adsorption separation of cymene oxidation products according to claim 1, characterized in that: The recovery rate of the tertiary peroxide TCHP of the cymene by the adsorption separation method is 90.0%-99.9%; and / or the recovery rate of the primary peroxide PCHP of the cymene by the adsorption separation method is 60.0%-99.5%.

14. A method for producing p-methylphenol, characterized in that: The production method comprises the following steps: 1) using cymene as a raw material to carry out a hydroperoxidation reaction to obtain a cymene oxidation product; 2) using the adsorption separation method for cymene oxidation products according to any one of claims 1 to 13 to adsorb and separate the cymene oxidation product to obtain the tertiary peroxide TCHP of cymene; 3) acidolyzing the tertiary peroxide TCHP of cymene to obtain the p-methylphenol.

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