Method for continuously producing cumyl dihydroperoxide

Abstract

The invention relates to the field of fine organic synthesis, in particular to a method for continuously producing cumyl dihydroperoxide. The fibers with specific diameters and surface contact angles are adopted as materials of the coalescence layer of the coalescence filter element, the raffinate oil phase is treated, most alkali in the raffinate oil phase can be removed, the alkali content of the raffinate oil phase is effectively controlled, and the recycled oil phase with the low alkali content is obtained. The recycled oil phase is reused in the oxidation reaction process, so that on one hand, the alkali input can be reduced, the process cost can be reduced, on the other hand, higher selectivity and purity can be realized, and the generation of byproducts can be reduced. The method for continuously producing cumyl dihydroperoxide has the advantages of good economy, high selectivity and few byproducts, and can meet the industrial production requirements.

Description

Technical Field

[0001] This application relates to the field of fine organic synthesis, and in particular to a method for the continuous production of cumene dipperoxide. Background Technology

[0002] The oxidation of dicumylbenzene to cumyl hydroperoxide is an important process route for producing fine chemicals. The resulting cumyl hydroperoxide can be cracked to produce resorcinol, which is widely used in wood adhesives, meta-methyl resins, and UV absorbers. However, this process generates 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene or 4-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene, especially when the alkali concentration in the reaction system is too high. The utilization value of this byproduct is relatively low, leading to a decrease in the economic efficiency of the process.

[0003] Meanwhile, in addition to cumene hydroperoxide and the aforementioned byproducts, the oxidation reaction solution also contains unreacted raw materials, reaction intermediates, and alkaline solutions, requiring purification and separation. After oil-water separation, alkaline extraction can separate cumene hydroperoxide from other raw materials (such as unreacted raw materials and reaction intermediates) in the oil phase. Cubic hydroperoxide enters the alkaline aqueous phase, while other raw materials remain in the raffinate oil phase. Reusing the raffinate oil phase back into the reaction system improves economic efficiency. However, the raffinate oil phase contains a large amount of dissolved sodium hydroxide, which significantly increases the pH of the reaction system when reused, leading to the production of large quantities of 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene or 4-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene.

[0004] Therefore, there is an urgent need to provide an economical, low-byproduct, continuous method for the production of cumene hydrogen peroxide. Summary of the Invention

[0005] Therefore, the main objective of this application is to provide an economical, low-byproduct, continuous method for the production of cumene dihydroperoxide to meet industrial production needs.

[0006] In a first aspect, this application provides a method for the continuous production of cumene hydrogen peroxide, comprising the following steps:

[0007] An oxygen-containing gas is introduced into a first mixture containing the first reaction raw material and the alkali to carry out an oxidation reaction and form an oxidation reaction solution.

[0008] A second reaction ingredient is added to the oxidation reaction solution to form a second mixture;

[0009] The second mixture is subjected to a first oil-water separation to form a first oil phase and a first aqueous phase;

[0010] The first oil phase is extracted with an alkaline solution, and then separated into a raffinate oil phase and a second aqueous phase by oil-water separation.

[0011] The residual oil phase is mixed with water to form an oil-water mixture, which is then separated by a coalescing filter element to form a reusable oil phase and a third aqueous phase. The coalescing layer of the coalescing filter element is made of hydrophilic and hydrophobic fibers. The diameters of the hydrophilic and hydrophobic fibers are each independently 0.1 μm-2 μm. The surface contact angle of the hydrophilic fibers is 10°~60°, and the surface contact angle of the hydrophobic fibers is 110°~160°.

[0012] The recycled oil phase is reused in the oxidation reaction step for oxidation reaction.

[0013] In some embodiments, the mass ratio of the raffinate oil phase to the water is (1-20):1.

[0014] In some embodiments, the mixing conditions in the step of mixing the raffinate oil phase with water include: a stirring intensity of 2 kW / m. 3 ~8kW / m 3 The stay is 1 to 5 hours.

[0015] In some embodiments, the conditions for coalescence separation also include a residence time of 1 to 5 hours.

[0016] In some embodiments, the first reactant and the second reactant each independently comprise diisopropylbenzene;

[0017] Optionally, the diisopropylbenzene includes at least one of m-diisopropylbenzene and p-diisopropylbenzene;

[0018] Optionally, the first reactant and the second reactant may each independently include at least one of m-mono-diisopropylbenzene and p-mono-diisopropylbenzene;

[0019] Optionally, the amount of the second reaction raw material added is 90wt% to 110wt% of the amount of diisopropylbenzene consumed in the oxidation reaction of the first reaction raw material.

[0020] In some embodiments, one or more of the following features are satisfied:

[0021] (1) The oxygen-containing gas includes air;

[0022] (2) The alkali includes at least one of sodium hydroxide and sodium carbonate;

[0023] (3) The pH of the oxidation reaction solution is 9~11.

[0024] In some embodiments, the conditions for the oxidation reaction include: a reaction temperature of 80°C-90°C; and a reaction time of 5h-15h.

[0025] In some embodiments, the first oil-water separation and the second oil-water separation include at least one of centrifugal separation, coalescence separation and sedimentation separation.

[0026] In some embodiments, one or more of the following features are satisfied:

[0027] (1) The alkaline solution includes at least one of sodium hydroxide aqueous solution and sodium carbonate aqueous solution;

[0028] (2) The mass concentration of the alkali in the alkaline solution is 5wt%~10wt%;

[0029] (3) Extraction conditions include: extraction temperature of 10℃~50℃, which can be selected as 15℃~25℃;

[0030] (4) Extraction conditions include: using an extraction tower for multi-stage countercurrent extraction, which can be selected as 3 to 7 stages of countercurrent extraction;

[0031] (5) The mass ratio of the first oil phase to the alkaline solution is 1:(0.8~1.5).

[0032] In some embodiments, the alkali content of the recycled oil phase is 500ppm to 1500ppm, and optionally 500ppm to 1000ppm.

[0033] Studies have found that in the process of oxidizing dicumylbenzene to prepare cumyl hydroperoxide, 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene or 4-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene are produced as byproducts during the oxidation process. Especially when the alkali concentration in the reaction system is too high, the already generated cumyl hydroperoxide will react with the alkali to generate monohydroperoxide or even benzyl alcohol byproducts, leading to a further increase in the above byproducts. The raffinate phase formed after alkali extraction of the oxidation products contains a large amount of cumene hydroperoxide, alcohols, and ketones, which will dissolve a large amount of alkali (such as sodium hydroxide). The alkali content can even reach 3000ppm-4000ppm. When recycled back to the reaction system, it will significantly increase the pH of the reaction system, resulting in a large amount of byproducts of 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene or 4-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene.

[0034] Because the raffinate oil phase has a high peroxide content, it has a high viscosity and good hydrophilicity, making it difficult to remove the alkali it contains.

[0035] Based on this, this application uses a coalescing filter element with a coalescing layer fiber diameter and surface contact angle within a defined range to treat the raffinate oil phase. On the one hand, the coalescing layer fiber has a small diameter, a large specific surface area, and high surface energy, significantly increasing the adsorption sites for polar components such as alkali and water. It can also "absorb" the alkali-containing water film onto the fiber surface, preventing it from short-circuiting out with the oil phase, thus facilitating the separation of polar components such as alkali and water from the oil phase. On the other hand, the coalescing layer's surface contact angle, within a defined range, has moderate hydrophilicity. Water droplets can wet the fibers, but the water film does not easily coat the fibers, making drainage difficult. This facilitates the spread, collision, and growth of water droplets on the fiber surface, leading to separation. This removes most of the alkali from the raffinate oil phase, effectively controlling its alkali content and obtaining a reusable oil phase with low alkali content. The reusable oil phase is then recycled in the oxidation reaction process, reducing alkali input and process costs, while also achieving higher selectivity and purity and reducing the generation of byproducts. This provides an economical, low-byproduct, continuous method for the production of cumene hydrogen peroxide to meet industrial production needs. Detailed Implementation

[0036] The present application will be further described in detail below with reference to specific embodiments. The present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0038] In this article, "one or more" refers to any one, two or more of the listed items.

[0039] In this application, terms such as "first aspect," "second aspect," "third aspect," and "fourth aspect" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, terms such as "first," "second," "third," and "fourth" serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0040] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0041] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0042] Unless otherwise specified, the percentage content mentioned in this application refers to mass percentage for solid-liquid mixtures and solid-phase-solid mixtures, and volume percentage for liquid-phase-liquid mixtures.

[0043] Unless otherwise specified, all percentage concentrations mentioned in this application refer to final concentrations. The final concentration refers to the percentage of the added component in the system after its addition. The concentrations of solutions mentioned in this application (such as lithium fluoride wastewater, lithium bicarbonate solution, etc.) all refer to the concentration at 25°C.

[0044] In this application, the content of organic components in the reaction products or raw materials is determined by liquid chromatography.

[0045] In this application, the reaction selectivity is calculated as follows: Reaction selectivity = Molar amount of diisopropylbenzene generated / Molar amount of diisopropylbenzene consumed × 100%.

[0046] In this application, the alkali content in the raw material is determined by titration, specifically as follows: pure water and the oil phase to be tested are mixed at a 1:1 ratio, and acid-base titration is performed using a Metrohm titrator.

[0047] In this application, the surface contact angle of the coalescing layer fibers was determined according to GB / T 30693-2014.

[0048] Unless otherwise specified, the temperature parameters in this application allow for both isothermal processing and processing within a certain temperature range. The isothermal processing allows temperature fluctuations within the precision range controlled by the instrument. Unless otherwise specified, the processing temperature in this application refers to room temperature. "Room temperature" means 20°C-30°C, and more specifically, 25°C.

[0049] In a first aspect, this application provides a method for the continuous production of cumene hydrogen peroxide, comprising the following steps:

[0050] An oxygen-containing gas is introduced into a first mixture containing the first reaction raw material and the alkali to carry out an oxidation reaction and form an oxidation reaction solution.

[0051] A second reaction ingredient is added to the oxidation reaction solution to form a second mixture;

[0052] The second mixture is subjected to a first oil-water separation to form a first oil phase and a first aqueous phase;

[0053] The first oil phase is extracted with an alkaline solution, and then separated into a raffinate oil phase and a second aqueous phase by oil-water separation.

[0054] The residual oil phase is mixed with water to form an oil-water mixture, which is then separated by a coalescing filter element to form a reusable oil phase and a third aqueous phase. The coalescing layer of the coalescing filter element is made of hydrophilic and hydrophobic fibers. The diameters of the hydrophilic and hydrophobic fibers are each independently 0.1 μm-2 μm. The surface contact angle of the hydrophilic fibers is 10°~60°, and the surface contact angle of the hydrophobic fibers is 110°~160°.

[0055] The recycled oil phase is reused in the oxidation reaction step for oxidation reaction.

[0056] This application utilizes a coalescing filter element with a coalescing layer whose fiber diameter and surface contact angle are within a defined range to treat the raffinate oil phase. On one hand, the coalescing layer fibers have a smaller diameter, resulting in a larger specific surface area and higher surface energy. This significantly increases the adsorption sites for polar components such as alkali and water, and allows the alkali-containing water film to be "absorbed" onto the fiber surface, preventing it from flowing out with the oil phase via a short circuit, thus facilitating the separation of polar components like alkali and water from the oil phase. On the other hand, the coalescing layer's surface contact angle, within a defined range, provides moderate hydrophilicity. Water droplets can wet the fibers, but the water film does not easily coat the fibers, hindering drainage. This promotes the spread, collision, and growth of water droplets on the fiber surface, leading to separation. This process removes most of the alkali from the raffinate oil phase, effectively controlling its alkali content and yielding a reusable oil phase with lower alkali content. The reusable oil phase is then recycled in the oxidation reaction process, reducing alkali input and lowering process costs. Furthermore, it achieves higher selectivity and purity while minimizing the generation of byproducts. This provides an economical, low-byproduct, continuous method for the production of cumene hydrogen peroxide to meet industrial production needs.

[0057] In some embodiments, the diameters of the hydrophilic and hydrophobic fibers can each be independently 0.1 μm, 0.5 μm, 1 μm, 1.5 μm, 2 μm, etc.; the surface contact angle of the hydrophilic fiber can be 10°, 20°, 40°, 60°, etc., and the surface contact angle of the hydrophobic fiber can be 110°, 120°, 130°, 140°, 150°, 160°, etc.

[0058] Understandably, the first mixture may also include impurities, catalyst, and water; the impurities include hydroxydiisopropylbenzene and other impurities generated in the process of oxidizing diisopropylbenzene to prepare cumene dihydroperoxide. Further, in the first mixture, the content of the first reaction raw material is 60wt%~95wt%; the content of impurities is less than 10wt%.

[0059] In some embodiments, the alkali content in the first mixture is 400ppm to 2000ppm, such as 400ppm, 500ppm, 1000ppm, 1500ppm, 2000ppm, etc.

[0060] In some embodiments, the mass ratio of the raffinate oil phase to the water is (1-20):1, for example, 1:1, 5:1, 10:1, 15:1, 20:1, etc.

[0061] In some embodiments, the mixing conditions in the step of mixing the raffinate oil phase with water include: a stirring intensity of 2 kW / m. 3 ~8kW / m 3 For example, 2kW / m 3 4kW / m 3 6kW / m 3 8kW / m 3 The stay duration is 1 hour to 5 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, etc.

[0062] In some embodiments, the conditions for coalescence separation also include a residence time of 1 to 5 hours, such as 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, etc.

[0063] In some embodiments, the first reactant and the second reactant each independently comprise diisopropylbenzene;

[0064] Optionally, the diisopropylbenzene includes at least one of m-diisopropylbenzene and p-diisopropylbenzene;

[0065] Optionally, the first reactant and the second reactant may each independently include at least one of m-mono-diisopropylbenzene and p-mono-diisopropylbenzene;

[0066] Optionally, the amount of the second reaction raw material added is 90wt% to 110wt% of the amount of diisopropylbenzene consumed in the oxidation reaction of the first reaction raw material, such as 90wt%, 95wt%, 100wt%, 105wt%, 110wt%, etc.

[0067] In some embodiments, one or more of the following features are satisfied:

[0068] (1) The oxygen-containing gas includes air;

[0069] (2) The alkali includes at least one of sodium hydroxide and sodium carbonate;

[0070] (3) The pH of the oxidation reaction solution is 9~11, for example 9, 10, 11, etc.

[0071] In some embodiments, the oxygen-containing gas is introduced at a rate of 15 kg / h to 60 kg / h, such as 15 kg / h, 20 kg / h, 30 kg / h, 40 kg / h, 50 kg / h, 60 kg / h, etc.

[0072] In some embodiments, the mass ratio of the first reaction material to the oxygen in the oxygen-containing gas is (1~8):1, for example, 1:1, 2:1, 4:1, 6:1, 8:1, etc.

[0073] In some embodiments, the conditions for the oxidation reaction include: a reaction temperature of 80℃-90℃, such as 80℃, 82℃, 84℃, 86℃, 88℃, 90℃, etc.; and a reaction time of 5h~15h, such as 5h, 7h, 10h, 12h, 15h, etc.

[0074] In some embodiments, the first oil-water separation and the second oil-water separation include at least one of centrifugal separation, coalescence separation and sedimentation separation.

[0075] In some embodiments, one or more of the following features are satisfied:

[0076] (1) The alkaline solution includes at least one of sodium hydroxide aqueous solution and sodium carbonate aqueous solution;

[0077] (2) The mass concentration of the alkali in the alkaline solution is 5wt%~10wt%, for example, 5wt%, 6wt%, 8wt%, 10wt%, etc.;

[0078] (3) Extraction conditions include: extraction temperature 10℃~50℃, which can be selected as 15℃~25℃, such as 10℃, 20℃, 30℃, 40℃, 50℃, etc.;

[0079] (4) Extraction conditions include: using an extraction tower for multi-stage countercurrent extraction, which can be selected as 3 to 7 stages of countercurrent extraction;

[0080] (5) The mass ratio of the first oil phase to the alkaline solution is 1:(0.8~1.5), for example, 1:0.8, 1:1, 1:1.2, 1:1.4, 1:1.5, etc.;

[0081] (6) The rate at which the alkaline solution is introduced is 50 kg / h to 200 kg / h, for example, 50 kg / h, 70 kg / h, 100 kg / h, 150 kg / h, 180 kg / h, 200 kg / h, etc.

[0082] In some embodiments, one or more of the following features are satisfied:

[0083] (1) The alkali content of the recycled oil phase is 500ppm~1500ppm, and can be selected as 500ppm~1000ppm, such as 500ppm, 700ppm, 1000ppm, 1300ppm, 1500ppm, etc.;

[0084] For experimental parameters not specified in the following specific embodiments, please refer to the guidelines given in this application document first, or refer to experimental manuals or other experimental methods known in the art, or refer to the experimental conditions recommended by the manufacturer.

[0085] Unless otherwise specified, all raw materials and reagents used in this application can be purchased commercially. The following is an example.

[0086] Analytical instruments:

[0087] Shimadzu LC-20A liquid chromatograph, chromatographic column: Shimadzu phenyl column, mobile phase: water and acetonitrile in a 1:1 ratio, analysis temperature: 30℃, analysis time: 2h.

[0088] The raw materials are described below:

[0089] Hydrophilic fiber: Modified PTFE fiber, with the following specifications: 60°, average diameter 2μm; 10°, average diameter 0.1μm; 30°, average diameter 1.5μm; 80°, average diameter 3μm; purchased from Shanghai Jinyou Fluorine Materials Co., Ltd.

[0090] Hydrophobic fiber: Modified PTFE fiber, with the following specifications: 160°, average diameter 0.1μm; 110°, average diameter 1.5μm; 130°, average diameter 2μm; 100°, average diameter 3μm; purchased from Shanghai Jinyou Fluorine Materials Co., Ltd.

[0091] Example 1

[0092] S1: The initial solution contains 44 wt% dicumyl peroxide, 6 wt% hydroxydicumyl peroxide, 40 wt% m-dicumyl peroxide, and 500 ppm sodium hydroxide. The remaining components are ketone impurities accumulated in the system. The initial solution and pure water are continuously fed into the S1 oxidation reactor at a rate of 100 kg / h and 12.5 kg / h, respectively, while air is simultaneously introduced at a rate of 42 kg / h to carry out the oxidation reaction. The oxidation temperature is 90℃, and the residence time is 5 h, yielding the oxidation reaction solution.

[0093] S2: Add m-diisopropylbenzene to the obtained oxidation reaction solution (add 100wt% of the amount of diisopropylbenzene consumed in the oxidation reaction in the first reaction feedstock) at a feed rate of 15kg / h to form a second mixture.

[0094] S3: The second mixture is continuously fed into the phase separation tank for the first oil-water separation, and the residence time is controlled at 10h to obtain the first oil phase and the first water phase.

[0095] S4: The first oil phase is subjected to alkaline extraction by passing an 8wt% sodium hydroxide aqueous solution at a rate of 100kg / h for five-stage countercurrent extraction. The mass ratio of the first oil phase to the alkaline solution is 1:0.8, and the extraction temperature is controlled at 25℃ to obtain the raffinate oil phase and the second aqueous phase.

[0096] S5: Mix the raffinate oil phase with water, and thoroughly stir both in a stirred tank. The mass ratio of the raffinate oil phase to water is 1:1; the stirring intensity is 2 kW / m. 3 The stirring residence time was 1 hour. The stirred oil-water mixture was then subjected to oil-water coalescence separation to obtain a reusable oil phase and a third aqueous phase. The hydrophilic and hydrophobic fibers of the coalescing layer of the coalescing filter element were both modified PTFE fibers. The average diameter of the hydrophilic fibers was 2 μm and the surface contact angle was 60°, while the average diameter of the hydrophobic fibers was 0.1 μm and the surface contact angle was 160°. The residence time was 5 hours.

[0097] S6: The oil phase with an alkali content of 600 ppm is recycled and used in reactor S1 for oxidation reaction.

[0098] In the oxidation reaction liquid at the outlet of reactor S1 after reuse, the mass ratio of cumene dihydroperoxide to 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene is 6:1, and the reaction selectivity is 91%.

[0099] Example 2

[0100] S1: The initial solution contains 47.5 wt% dicumyl peroxide, 6.5 wt% hydroxydicumyl peroxide, 34 wt% m-dicumyl peroxide, and 1500 ppm sodium hydroxide. The remaining components are ketone impurities accumulated in the system. The initial solution and pure water are continuously fed into the S1 oxidation reactor at a rate of 100 kg / h and 12.5 kg / h, respectively, while air is simultaneously introduced at a rate of 21 kg / h to carry out the oxidation reaction. The oxidation temperature is 80℃, and the residence time is 15 h, yielding the oxidation reaction solution.

[0101] S2: Add p-diisopropylbenzene to the obtained oxidation reaction solution (add 100wt% of the amount of diisopropylbenzene consumed in the oxidation reaction in the first reaction feedstock) at a feed rate of 7.5 kg / h to form a second mixture.

[0102] S3: The second mixture is continuously fed into a centrifuge for the first oil-water separation. The centrifugation speed is 1000 rpm and the residence time is 1 min to obtain the first oil phase and the first water phase.

[0103] S4: The first oil phase is subjected to alkaline extraction by passing an 8wt% sodium hydroxide aqueous solution at a rate of 80kg / h for five-stage countercurrent extraction. The mass ratio of the first oil phase to the alkaline solution is 1:1.5, and the extraction temperature is controlled at 25℃ to obtain the raffinate oil phase and the second aqueous phase.

[0104] S5: Mix the raffinate oil phase with water, and thoroughly stir both in a stirred tank. The mass ratio of the raffinate oil phase to water is 20:1; the stirring intensity is 8 kW / m. 3 The stirring residence time was 5 hours. The stirred oil-water mixture was then subjected to oil-water coalescence separation to obtain a reusable oil phase and a third aqueous phase. The hydrophilic and hydrophobic fibers of the coalescing layer of the coalescing filter element were both modified PTFE fibers. The average diameter of the hydrophilic fibers was 0.1 μm and the surface contact angle was 10°, while the average diameter of the hydrophobic fibers was 1.5 μm and the surface contact angle was 110°. The residence time was 1 hour.

[0105] S6: The oil phase with an alkalinity of 500 ppm is recycled and used in reactor S1 for oxidation reaction.

[0106] In the oxidation reaction liquid at the outlet of reactor S1 after reuse, the mass ratio of cumene dihydroperoxide to 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene is 8:1, and the reaction selectivity is 92%.

[0107] Example 3

[0108] Compared with Example 1, the difference lies in step S5, which is as follows: the raffinate oil phase is mixed with water, and the two are thoroughly stirred in a stirred tank. The mass ratio of the raffinate oil phase to water is 10:1; the stirring intensity is 5 kW / m. 3 The stirring residence time was 3 hours, and the water flow rate was 12 kg / h. The stirred oil-water mixture was then subjected to oil-water coalescence separation to obtain a reusable oil phase and a third aqueous phase. The hydrophilic and hydrophobic fibers of the coalescing layer of the coalescing filter element were both modified PTFE fibers. The average diameter of the hydrophilic fibers was 1.5 μm, and the surface contact angle was 30°. The average diameter of the hydrophobic fibers was 2 μm, and the surface contact angle was 130°. The residence time was 2 hours.

[0109] The recycled oil phase contains 1000 ppm of alkali. After recycling, the mass ratio of cumene dihydroperoxide to 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene in the oxidation reaction liquid at the outlet of reactor S1 is 7:1, and the reaction selectivity is 91.5%.

[0110] Comparative Example 1

[0111] Compared with Example 1, the difference is that step S5 is omitted, and the raffinate oil phase in reactor S1 is directly oxidized. The raffinate oil phase contains 5000 ppm of alkali.

[0112] In the oxidation reaction liquid at the outlet of reactor S1 after reuse, the mass ratio of cumene dihydroperoxide to 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene is 3:1, and the reaction selectivity is 86%.

[0113] Comparative Example 2

[0114] Compared with Example 1, the difference is that the hydrophilic fiber specifications are: modified PTFE fiber, 80°, with an average diameter of 3μm.

[0115] The recycled oil phase contains 3000 ppm of alkali. After recycling, the mass ratio of cumene dihydroperoxide to 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene in the oxidation reaction liquid at the outlet of reactor S1 is 3:1, and the reaction selectivity is 85%.

[0116] Comparative Example 3

[0117] Compared with Example 1, the difference is that the hydrophobic fiber specifications are: modified PTFE fiber, 100°, with an average diameter of 3μm.

[0118] The recycled oil phase contains 4000 ppm of alkali. After recycling, the mass ratio of cumene dihydroperoxide to 3-(2-hydroxy-2-propyl)-1-(2-hydroperoxy-2-propyl)benzene in the oxidation reaction liquid at the outlet of reactor S1 is 3:1, and the reaction selectivity is 84%.

[0119] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0120] The embodiments described above are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. It should be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A method for continuous production of cumene hydrogen peroxide, characterized in that, Includes the following steps: An oxygen-containing gas is introduced into a first mixture containing the first reaction raw material and the alkali to carry out an oxidation reaction and form an oxidation reaction solution. A second reaction ingredient is added to the oxidation reaction solution to form a second mixture; The second mixture is subjected to a first oil-water separation to form a first oil phase and a first aqueous phase; The first oil phase is extracted with an alkaline solution, and then separated into a raffinate oil phase and a second aqueous phase by oil-water separation. The residual oil phase is mixed with water to form an oil-water mixture, which is then separated by a coalescing filter element to form a reusable oil phase and a third aqueous phase. The coalescing layer of the coalescing filter element is made of hydrophilic and hydrophobic fibers. The diameters of the hydrophilic and hydrophobic fibers are each independently 0.1 μm-2 μm. The surface contact angle of the hydrophilic fibers is 10°~60°, and the surface contact angle of the hydrophobic fibers is 110°~160°. The recycled oil phase is reused in the oxidation reaction step for oxidation reaction.

2. The method as described in claim 1, characterized in that, The mass ratio of the raffinate oil phase to the water is (1-20):

1.

3. The method as described in claim 1, characterized in that, In the step of mixing the raffinate oil phase with water, the mixing conditions include: a stirring intensity of 2 kW / m. 3 ~8kW / m 3 The stay is 1 to 5 hours.

4. The method as described in claim 1, characterized in that, The conditions for coalescence separation also include a residence time of 1 to 5 hours.

5. The method according to any one of claims 1-4, characterized in that, The first reactant and the second reactant each independently comprise diisopropylbenzene; Optionally, the diisopropylbenzene includes at least one of m-diisopropylbenzene and p-diisopropylbenzene; Optionally, the first reactant and the second reactant may each independently include at least one of m-mono-diisopropylbenzene and p-mono-diisopropylbenzene; Optionally, the amount of the second reaction raw material added is 90wt% to 110wt% of the amount of diisopropylbenzene consumed in the oxidation reaction of the first reaction raw material.

6. The method according to any one of claims 1-4, characterized in that, It meets one or more of the following characteristics: (1) The oxygen-containing gas includes air; (2) The alkali includes at least one of sodium hydroxide and sodium carbonate; (3) The pH of the oxidation reaction solution is 9~11.

7. The method according to any one of claims 1-4, characterized in that, The conditions for the oxidation reaction include: a reaction temperature of 80℃-90℃ and a reaction time of 5h-15h.

8. The method according to any one of claims 1-4, characterized in that, The first oil-water separation and the second oil-water separation include at least one of centrifugal separation, coalescence separation and sedimentation separation.

9. The method according to any one of claims 1-4, characterized in that, It meets one or more of the following characteristics: (1) The alkaline solution includes at least one of sodium hydroxide aqueous solution and sodium carbonate aqueous solution; (2) The mass concentration of the alkali in the alkaline solution is 5wt%~10wt%; (3) Extraction conditions include: extraction temperature of 10℃~50℃, which can be selected as 15℃~25℃; (4) Extraction conditions include: using an extraction tower for multi-stage countercurrent extraction, which can be selected as 3 to 7 stages of countercurrent extraction; (5) The mass ratio of the first oil phase to the alkaline solution is 1:(0.8~1.5).

10. The method according to any one of claims 1-4, characterized in that, The alkali content of the recycled oil phase is 500ppm~1500ppm, and can be selected as 500ppm~1000ppm.