Isopropylbenzene oxidation reaction system and method

Abstract

The invention relates to the technical field of cumene oxidation, in particular to a cumene oxidation reaction system and method.The system comprises an oxidation tower and a gas-liquid separator; a bubbling reactor and a microbubble generator are sequentially arranged in the oxidation tower from top to bottom, the bottom of the oxidation tower is connected with gas supply equipment and liquid supply equipment, the top of the oxidation tower is connected with the gas-liquid separator, the top of the gas-liquid separator is connected with condensing equipment and the gas supply equipment, and the gas supply equipment is connected with the liquid supply equipment. The condensation equipment is connected with oxygen analysis equipment, and liquid circulation equipment is arranged between the bottom of the gas-liquid separator and the bottom of the oxidation tower and is used for circularly conveying liquid in the gas-liquid separator into the microbubble generator. By applying the system, the efficiency of generating cumene hydroperoxide by oxidizing cumene can be effectively improved, and the system has the advantages of high cumene hydroperoxide generation rate, high selectivity and high safety.

Description

Technical Field

[0001] The invention relates to the technical field of cumene oxidation, and in particular to a cumene oxidation reaction system and method. Background Art

[0002] As an important chemical raw material, phenol is often used to prepare chemical intermediates and various fine chemicals, such as epoxy resin, phenolic resin, polycarbonate, salicylic acid, etc. At present, more than 90% of phenol in industry is synthesized through the cumene oxidation process route, and acetone is co-produced. The main production steps are as follows: (1) Benzene and propylene undergo alkylation reaction to produce cumene; (2) Cumene is oxidized by air to form cumene hydroperoxide (CHP); (3) CHP is decomposed under acidic conditions to produce equimolar amounts of phenol and acetone. Among them, the oxidation process of cumene is a key step affecting the purity and yield of phenol. However, the traditional cumene oxidation process has many defects, such as slow reaction rate and low selectivity of the target product. In recent years, research on the cumene oxidation process at home and abroad has mainly focused on improving the conversion rate and selectivity. However, the reaction temperature and pressure are high, the cost is also high, and because the cumene oxidation reaction mechanism is relatively complex and is essentially a slow reaction process, the effect of improving the process conditions is also very limited.

[0003] At the same time, there are also solutions using catalysts in the prior art. Although the use of catalysts can significantly improve the oxidation efficiency, it will also make the process more complicated, and many problems in the separation and reuse of catalysts are difficult to solve. In addition, non-catalytic oxidation has also been widely used in industrial applications, but its initial reaction speed is very slow, there is a long induction period, and the target product CHP has low selectivity and low generation rate, which is not conducive to large-scale production.

[0004] Patent Publication No.: CN106588734A discloses a method and device for preparing cumene hydroperoxide by oxidation of cumene, which specifically discloses that cumene and an initiator are introduced into a microreactor group formed by connecting one or more microreactors in series, and a continuous flow oxidation reaction is performed recursively in sequence until the reaction product flows into the last microreactor for oxidation reaction, and finally flash distillation purification; in each oxidation reaction process, oxygen is introduced into all microreactors, and the molar ratio of cumene introduced into the first microreactor to the total oxygen introduced into all microreactors is 0.1:5. This solution solves the problems of large reaction temperature fluctuation, low production efficiency and low yield in traditional processes, but microreactor technology is a forward-looking technology and is still very difficult to realize in industry.

[0005] Therefore, there is an urgent need for a cumene oxidation reaction system and method. Summary of the invention

[0006] The invention provides a cumene oxidation reaction system and method to solve the problems of low efficiency of cumene oxidation to generate cumene hydroperoxide and low selectivity of target product CHP in conventional cumene oxidation reaction equipment in the prior art.

[0007] In order to achieve the above-mentioned object, the present invention provides a cumene oxidation reaction system in a first aspect, the system comprising an oxidation tower and a gas-liquid separator;

[0008] The interior of the oxidation tower is provided with a bubbling reactor and a microbubble generator in sequence from top to bottom; the bottom of the oxidation tower is respectively connected to a gas supply device and a liquid supply device, and the top is connected to the gas-liquid separator; the top of the gas-liquid separator is respectively connected to a condensing device and the gas supply device, and the condensing device is connected to an oxygen analysis device; a liquid circulation device is provided between the bottom of the gas-liquid separator and the bottom of the oxidation tower, and is used for circulating the liquid inside the gas-liquid separator to the inside of the microbubble generator.

[0009] Preferably, the microbubble generator is a ceramic membrane microbubble generator.

[0010] Preferably, the average pore size of the ceramic membrane of the ceramic membrane microbubble generator is 10 nm to 10 μm, the porosity is 30 to 35%, and the transmembrane pressure difference is 0.2 to 0.5 MPa.

[0011] Preferably, the oxidation tower further comprises a first heating device for maintaining the temperature inside the oxidation tower at 90-130° C. during the cumene oxidation reaction.

[0012] Preferably, the gas-liquid separator further comprises a second heating device for maintaining the temperature inside the gas-liquid separator at 90-130° C. during the cumene oxidation reaction.

[0013] Preferably, the condensation equipment comprises a condensation tank and a circulation cooler arranged on the condensation tank, and the circulation cooler is used to maintain the temperature inside the condensation tank at 20-40°C.

[0014] Preferably, the bottom of the condensation tank is connected to the top of the gas-liquid separator, and the top is connected to the oxygen analysis equipment, and a wire mesh corrugated filler is arranged inside the condensation tank.

[0015] Preferably, the system further comprises a reaction pressure control device for maintaining the gauge pressure inside the oxidation tower at 0-0.4 MPa during the cumene oxidation reaction.

[0016] Preferably, the circulating and transporting of the liquid in the gas-liquid separator to the interior of the microbubble generator specifically includes:

[0017] During the cumene oxidation reaction, the liquid in the gas-liquid separator is circulated and transported to the inside of the microbubble generator at a rate of 0-20 L / min, and the liquid level in the gas-liquid separator is maintained at 30-65%.

[0018] Preferably, the gas supply device is used to deliver protective gas and / or reaction gas to the interior of the microbubble generator, and to deliver protective gas to the top of the gas-liquid separator.

[0019] Preferably, the gas supply device is used to introduce reaction gas into the interior of the microbubble generator at a rate of 0-5 L / min during the cumene oxidation reaction.

[0020] Preferably, the protective gas is an inert gas, and the reactive gas is air.

[0021] Preferably, a preheater is provided between the gas supply equipment and the oxidation tower.

[0022] Preferably, the liquid supply device is used to introduce a reaction liquid into the interior of the microbubble generator, and the reaction liquid is a cumene mixed liquid containing 0-15% cumene hydroperoxide.

[0023] A second aspect of the present invention provides a cumene oxidation reaction method, which is implemented using the above-mentioned cumene oxidation reaction system, and the method comprises the following steps:

[0024] S1, the liquid supply device transports the reaction liquid into the oxidation tower, and when the interior of the oxidation tower is filled with the reaction liquid and the liquid level of the reaction liquid in the gas-liquid separator reaches 20-30%, the reaction liquid is stopped from being transported into the oxidation tower;

[0025] S2, the liquid circulation device circulates the liquid inside the gas-liquid separator to the oxidation tower, and maintains the liquid level inside the gas-liquid separator at 20-60%;

[0026] S3, the protective gas preheated to 80-90°C by the preheater is introduced into the oxidation tower, the first heating device maintains the temperature inside the oxidation tower at 80-90°C, the second heating device maintains the temperature inside the gas-liquid separator at 80-90°C, and the circulating cooler maintains the internal temperature of the condensation tank at 20-40°C;

[0027] S4, after the bubble flow in the oxidation tower is stable, the temperature inside the oxidation tower and the temperature inside the gas-liquid separator are both stable at 80-90° C., and the liquid level inside the gas-liquid separator is stable at 20-60%, the temperature inside the oxidation tower and the temperature inside the gas-liquid separator are raised to 90-130° C.;

[0028] S5. The reaction pressure control device is used to maintain the internal gauge pressure of the oxidation tower at 0-0.4MPa; the reaction gas preheated to 80-90°C by the preheater is introduced into the oxidation tower at a rate of 0-5L / min, and the feed rate of the protective gas is gradually reduced to zero, and the liquid in the gas-liquid separator is circulated to the oxidation tower at a rate of 0-20L / min, and the liquid level in the gas-liquid separator is maintained at 30-65%; wherein, the reading of the oxygen analysis device is controlled to always remain at 6-9.5% during the oxidation reaction.

[0029] According to the above technical scheme, based on the isopropylbenzene oxidation reaction system, in actual application, isopropylbenzene is first oxidized by the oxidation tower, and then the gas and liquid are separated by the gas-liquid separator, and the isopropylbenzene component in the gas is recovered by the condensing equipment, and the liquid is circulated to the oxidation tower by the liquid circulation equipment, which can effectively improve the oxidation efficiency of isopropylbenzene, and has the advantages of high isopropylbenzene hydroperoxide generation rate, high selectivity and high safety. Furthermore, by using the oxygen analysis equipment in conjunction with the gas supply equipment, it can further effectively prevent the oxygen concentration at the top of the gas-liquid separator from being too high and from combusting and exploding with the isopropylbenzene gas component, which has the advantage of higher safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the cumene oxidation reaction system.

[0031] Description of Reference Numerals

[0032] Oxidation tower 1; microbubble generator 11; bubbling reactor 12; first heating device 13;

[0033] Gas-liquid separator 2; second heating device 21; reaction liquid storage tank 3; preheater 4;

[0034] Condensation equipment 5; condensation tank 51; wire mesh corrugated filler 511; circulation cooler 52;

[0035] Oxygen analysis equipment6. DETAILED DESCRIPTION

[0036] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0037] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, unless otherwise specified, features defined as "first" and "second" may explicitly or implicitly include one or more of the features; "plurality" means two or more. The term "include" and any variation thereof means non-exclusive inclusion, possible presence or addition of one or more other features, units, components and / or combinations thereof.

[0038] In addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internally connected between two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0039] The first aspect of the present invention provides a cumene oxidation reaction system, such as Figure 1 As shown, the cumene oxidation reaction system includes an oxidation tower 1 and a gas-liquid separator 2;

[0040] The interior of the oxidation tower 1 is sequentially provided with a bubbling reactor 12 and a microbubble generator 11 from top to bottom; the bottom of the oxidation tower 1 is respectively connected to a gas supply device and a liquid supply device, and the top is connected to the gas-liquid separator 2; the top of the gas-liquid separator 2 is respectively connected to a condensation device 5 and the gas supply device; the condensation device 5 is connected to an oxygen analysis device 6; a liquid circulation device is provided between the bottom of the gas-liquid separator 2 and the bottom of the oxidation tower 1, for circulating the liquid inside the gas-liquid separator 2 to the interior of the microbubble generator 11.

[0041] According to the above technical scheme, based on the isopropylbenzene oxidation reaction system, in actual application, isopropylbenzene is first oxidized by the oxidation tower, and then the gas and liquid are separated by the gas-liquid separator, and the isopropylbenzene component in the gas is recovered by the condensing equipment, and the liquid is circulated to the oxidation tower by the liquid circulation equipment, which can effectively improve the oxidation efficiency of isopropylbenzene, and has the advantages of high isopropylbenzene hydroperoxide generation rate, high selectivity and high safety. Furthermore, by using the oxygen analysis equipment in conjunction with the gas supply equipment, it can further effectively prevent the oxygen concentration at the top of the gas-liquid separator from being too high and from combusting and exploding with the isopropylbenzene gas component, which has the advantage of higher safety.

[0042] In the cumene oxidation reaction system of the present invention, in a preferred embodiment, the microbubble generator 11 is a ceramic membrane microbubble generator, which can effectively improve the efficiency of the cumene oxidation reaction, thereby improving the generation rate and selectivity of cumene hydroperoxide.

[0043] In a further preferred embodiment, the ceramic membrane of the ceramic membrane microbubble generator has an average pore size of 10 nm to 10 μm, a porosity of 30 to 35%, and a transmembrane pressure difference of 0.2 to 0.5 MPa. In practical applications, the efficiency of the cumene oxidation reaction can be further significantly improved, thereby improving the generation rate and selectivity of cumene hydroperoxide.

[0044] In the cumene oxidation reaction system of the present invention, in a preferred embodiment, the oxidation tower 1 further comprises a first heating device 13, which is used to maintain the temperature inside the oxidation tower 1 at 90-130°C during the cumene oxidation reaction. Preferably, the first heating device 13 is used to maintain the temperature inside the oxidation tower 1 at 90-110°C during the cumene oxidation reaction. Most preferably, the first heating device 13 is used to maintain the temperature inside the oxidation tower 1 at 100°C during the cumene oxidation reaction. Thus, the efficiency of the cumene oxidation reaction is effectively improved at the temperature level, and the optimal value of the cumene hydroperoxide generation rate and selectivity is obtained. In a specific embodiment, the first heating device 13 comprises a heat transfer oil machine and a hot oil pump. In actual application, the heat transfer oil machine is used to heat the heat transfer oil, and the hot oil pump is used to heat the oxidation tower 1 in a circulating manner, and stabilize it at a set temperature value.

[0045] In the cumene oxidation reaction system of the present invention, in a preferred embodiment, the gas-liquid separator 2 further comprises a second heating device 21, which is used to maintain the temperature inside the gas-liquid separator 2 at 90-130°C during the cumene oxidation reaction. Preferably, the second heating device 21 is used to maintain the temperature inside the gas-liquid separator 2 at 90-110°C during the cumene oxidation reaction. Most preferably, the second heating device 21 is used to maintain the temperature inside the gas-liquid separator 2 at 100°C during the cumene oxidation reaction. Thus, in conjunction with the oxidation tower 1, the efficiency of the cumene oxidation reaction is effectively improved at the temperature level, and the optimal value of the cumene hydroperoxide generation rate and selectivity is obtained. In a specific embodiment, the second heating device 21 is an electric heating furnace.

[0046] In a preferred embodiment of the cumene oxidation reaction system of the present invention, the condensation device 5 includes a condensation tank 51 and a circulating cooler 52 disposed on the condensation tank 51. The circulating cooler 52 can maintain the temperature inside the condensation tank 51 at 20-40°C; and further, by disposing a wire mesh corrugated filler 511 inside the condensation tank 51, the cumene component in the gas can be effectively recovered and explosion-proof can be effectively achieved.

[0047] Further in a preferred embodiment, the bottom of the condensation tank 51 is connected to the top of the gas-liquid separator 2 , and the top is connected to the oxygen analysis equipment 6 .

[0048] In a preferred embodiment, the cumene oxidation reaction system of the present invention further comprises a reaction pressure control device for maintaining the gauge pressure inside the oxidation tower 1 at 0-0.4 MPa during the cumene oxidation reaction. Preferably, the reaction pressure control device is used to maintain the gauge pressure inside the oxidation tower 1 at 0.2-0.4 MPa during the cumene oxidation reaction. Most preferably, the gauge pressure inside the oxidation tower 1 is maintained at 0.3 MPa. Thereby, the oxidation efficiency of cumene is further improved at the gauge pressure level inside the oxidation tower 1, and the optimal values ​​of the cumene hydroperoxide generation rate and selectivity are obtained.

[0049] In a preferred embodiment of the cumene oxidation reaction system of the present invention, the liquid inside the gas-liquid separator 2 is circulated and transported to the inside of the microbubble generator 11, specifically comprising:

[0050] During the cumene oxidation reaction, the liquid inside the gas-liquid separator 2 is circulated and transported to the inside of the microbubble generator 11 at a rate of 0-20 L / min, and the liquid level of the liquid inside the gas-liquid separator 2 is maintained at 30-65%, which can effectively improve the oxidation efficiency of cumene. Preferably, the liquid inside the gas-liquid separator 2 is circulated and transported to the inside of the microbubble generator 11 at a rate of 2-8 L / min, and the liquid level of the liquid inside the gas-liquid separator 2 is maintained at 40-60%.

[0051] In a preferred embodiment of the isopropylbenzene oxidation reaction system of the present invention, the gas supply device is used to transport protective gas and / or reaction gas to the interior of the microbubble generator 11, and to transport protective gas to the top of the gas-liquid separator 2.

[0052] In an embodiment of the present invention, in actual application, preferably, the gas supply device is used to pass the reaction gas into the microbubble generator 11 at a rate of 0-5L / min during the oxidation reaction of cumene. More preferably, the gas supply device is used to pass the reaction gas into the microbubble generator 11 at a rate of 2-4L / min during the oxidation reaction of cumene, thereby further improving the oxidation efficiency of cumene. Wherein, the gas supply device is used to deliver protective gas to the top of the gas-liquid separator 2, specifically, according to the oxygen concentration at the top of the gas-liquid separator 2 measured by the oxygen analysis device 6, the amount of protective gas passed is controlled, so as to achieve the effect of diluting the oxygen concentration, and then by maintaining the oxygen concentration at the top of the gas-liquid separator 2 below the limit oxygen concentration, thereby effectively preventing combustion and explosion. Specifically, the protective gas is an inert gas, preferably nitrogen, and the reaction gas is air, preferably oxygen-enriched air; the oxygen concentration in the tail gas is controlled to be 6-9.5%, preferably 6-8%; the oxygen analysis equipment 6 can be an oxygen analyzer, or other equipment with the same function.

[0053] Further in a preferred embodiment, a preheater 4 is provided between the gas supply device and the oxidation tower 1, so that in actual application, the oxidation efficiency of isopropylbenzene can be improved by first heating the protective gas and / or reaction gas to a preset temperature and then introducing the protective gas and / or reaction gas into the oxidation tower 1 for reaction.

[0054] In the isopropylbenzene oxidation reaction system of the present invention, in a preferred embodiment, the liquid supply device is used to pass the reaction liquid into the interior of the microbubble generator 11, and the reaction liquid is a cumene mixed liquid containing 0-15% cumene hydroperoxide. Preferably, the reaction liquid is a cumene mixed liquid containing 5-10% cumene hydroperoxide. Most preferably, the reaction liquid is a cumene mixed liquid containing 8% cumene hydroperoxide. Thereby, at the level of initiator (CHP) concentration, the oxidation efficiency of cumene is further improved, and the optimal values ​​of cumene hydroperoxide generation rate and selectivity are obtained. In a specific embodiment, as Figure 1 As shown, the reaction liquid is stored in a reaction liquid storage tank 3 and transported to the oxidation tower 1 by pumping.

[0055] The second aspect of the present invention also provides a cumene oxidation reaction method, which is implemented using the above-mentioned cumene oxidation reaction system, and the method comprises the following steps:

[0056] S1, the liquid supply device transports the reaction liquid into the oxidation tower 1, and when the interior of the oxidation tower 1 is filled with the reaction liquid and the liquid level of the reaction liquid in the gas-liquid separator 2 reaches 20-30%, the reaction liquid is stopped from being transported into the oxidation tower 1;

[0057] In step S1, preferably, when the liquid level of the reaction liquid inside the gas-liquid separator 2 reaches 20%, the reaction liquid is stopped from being transported into the oxidation tower 1.

[0058] S2, the liquid circulation device circulates the liquid in the gas-liquid separator 2 to the oxidation tower 1, and maintains the liquid level in the gas-liquid separator 2 at 20-60%;

[0059] S3, the protective gas preheated to 80-90°C by the preheater 4 is introduced into the oxidation tower 1, the first heating device 13 maintains the temperature inside the oxidation tower 1 at 80-90°C, the second heating device 21 maintains the temperature inside the gas-liquid separator 2 at 80-90°C, and the circulating cooler 52 maintains the internal temperature of the condensation tank 51 at 20-40°C;

[0060] In step S3, preferably, the protective gas preheated to 80°C by the preheater 4 is introduced into the oxidation tower 1, so that the temperature inside the oxidation tower 1 is maintained at 80°C, the temperature inside the gas-liquid separator 2 is maintained at 80°C, and the internal temperature of the condensation tank 51 is maintained at 20°C.

[0061] S4, after the bubble flow in the oxidation tower 1 is stable, the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are both stable at 80-90°C, and the liquid level inside the gas-liquid separator 2 is stable at 20-60%, the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 90-130°C;

[0062] In step S4, preferably, after the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are both stabilized at 80°C, and the liquid level inside the gas-liquid separator 2 is stabilized at 20-60%, the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 90-110°C.

[0063] S5. The reaction pressure control device is used to maintain the internal gauge pressure of the oxidation tower 1 at 0-0.4MPa; the reaction gas preheated to 80-90°C by the preheater 4 is introduced into the oxidation tower 1 at a rate of 0-5L / min, and the rate of the protective gas is gradually reduced to zero, and the liquid in the gas-liquid separator 2 is circulated to the oxidation tower 1 at a rate of 0-20L / min, and the liquid level of the liquid in the gas-liquid separator 2 is maintained at 30-65%; wherein, the reading of the oxygen analysis device is controlled to always remain at 6-9.5% during the oxidation reaction.

[0064] In step S5, preferably, the gauge pressure inside the oxidation tower 1 is maintained at 0.2-0.4MPa, and the reaction gas preheated to 80°C by the preheater 4 is introduced into the oxidation tower 1 at a rate of 2-4L / min; the liquid inside the gas-liquid separator 2 is circulated to the oxidation tower 1 at a rate of 2-8L / min, and the liquid level of the liquid inside the gas-liquid separator 2 is maintained at 40-60%; during the oxidation reaction, the reading of the oxygen analysis equipment is controlled to always remain at 6-8%.

[0065] The cumene oxidation reaction method of the present invention, in actual application, first oxidizes cumene through the oxidation tower, then separates gas and liquid through the gas-liquid separator, recovers the cumene component in the gas through the condensing equipment, and circulates the liquid into the oxidation tower through the liquid circulation equipment, which can effectively improve the oxidation efficiency of cumene, and has the advantages of high cumene hydroperoxide generation rate, high selectivity and high safety. Furthermore, by using the oxygen analysis equipment in conjunction with the gas supply equipment, it can further effectively prevent the excessive oxygen concentration at the top of the gas-liquid separator from combusting and exploding with the cumene gas component, which has the advantage of higher safety.

[0066] The present invention will be described in detail below through examples, but the protection scope of the present invention is not limited thereto.

[0067] Use Figure 1 The cumene oxidation reaction system shown is implemented, specifically, the system includes an oxidation tower 1 and a gas-liquid separator 2;

[0068] The interior of the oxidation tower 1 is sequentially provided with a bubbling reactor 12 and a microbubble generator 11 from top to bottom; the bottom of the oxidation tower 1 is respectively connected to a gas supply device and a liquid supply device, and the top is connected to the gas-liquid separator 2; the top of the gas-liquid separator 2 is respectively connected to a condensation device 5 and the gas supply device; the condensation device 5 is connected to an oxygen analysis device 6; a liquid circulation device is provided between the bottom of the gas-liquid separator 2 and the bottom of the oxidation tower 1, for circulating the liquid inside the gas-liquid separator 2 to the interior of the microbubble generator 11.

[0069] Specifically, the microbubble generator 11 is a ceramic membrane microbubble generator.

[0070] The ceramic membrane of the ceramic membrane microbubble generator has an average pore size of 300 nm, a porosity of 35%, and a transmembrane pressure difference of 0.3 MPa.

[0071] The oxidation tower 1 further comprises a first heating device 13, which is used to maintain the temperature inside the oxidation tower 1 at 90-130°C during the cumene oxidation reaction.

[0072] The gas-liquid separator 2 further comprises a second heating device 21 for maintaining the temperature inside the gas-liquid separator 2 at 90-130° C. during the cumene oxidation reaction.

[0073] The condensation device 5 includes a condensation tank 51 and a circulation cooler 52 disposed on the condensation tank 51 . The circulation cooler 52 is used to maintain the temperature inside the condensation tank 51 at 20-40° C.

[0074] The bottom of the condensation tank 51 is connected to the top of the gas-liquid separator 2 , and the top is connected to the oxygen analysis device 6 . A metal wire mesh corrugated filler 511 is arranged inside the condensation tank 51 .

[0075] The system also includes a reaction pressure control device for maintaining the pressure inside the oxidation tower 1 at 0-0.4 MPa during the cumene oxidation reaction.

[0076] The circulating and transporting of the liquid in the gas-liquid separator 2 to the inside of the microbubble generator 11 specifically includes:

[0077] During the cumene oxidation reaction, the liquid in the gas-liquid separator 2 is circulated and transported to the inside of the microbubble generator 11 at a rate of 0-20 L / min, and the liquid level in the gas-liquid separator 2 is maintained at 30-65%.

[0078] The gas supply device is used to deliver protective gas and / or reaction gas to the interior of the microbubble generator 11 , and is used to deliver protective gas to the top of the gas-liquid separator 2 .

[0079] The gas supply device is used to introduce reaction gas into the microbubble generator 11 at a rate of 0-5 L / min during the cumene oxidation reaction.

[0080] The protective gas is nitrogen, and the reactive gas is air.

[0081] A preheater 4 is provided between the gas supply device and the oxidation tower 1 .

[0082] The liquid supply device is used to introduce a reaction liquid into the microbubble generator 11 , wherein the reaction liquid is a cumene mixed liquid containing 0-15% cumene hydroperoxide.

[0083] In the actual application process, S1, the liquid supply device transports the reaction liquid into the oxidation tower 1, and when the interior of the oxidation tower 1 is filled with the reaction liquid and the internal reaction liquid level of the gas-liquid separator 2 reaches 20%, the reaction liquid is stopped from being transported into the oxidation tower 1;

[0084] S2, the liquid circulation device circulates the liquid in the gas-liquid separator 2 to the oxidation tower 1, and maintains the liquid level in the gas-liquid separator 2 at 50%;

[0085] S3, the protective gas preheated to 80°C by the preheater 4 is introduced into the oxidation tower 1, the first heating device 13 maintains the temperature inside the oxidation tower 1 at 80°C, the second heating device 21 maintains the temperature inside the gas-liquid separator 2 at 80°C, and the circulating cooler 52 maintains the internal temperature of the condensation tank 51 at 20°C;

[0086] S4, after the bubble flow in the oxidation tower 1 is stable, the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are both stable at 80°C, and the liquid level inside the gas-liquid separator 2 is stable at 50%, the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 90-130°C;

[0087] S5. The reaction pressure control device is used to maintain the pressure inside the oxidation tower 1 at 0-0.4MPa, and the reaction gas preheated to 80°C by the preheater 4 is introduced into the oxidation tower 1 at a rate of 0-5L / min, and the rate of the protective gas is reduced to zero; at the same time, the liquid inside the gas-liquid separator 2 is circulated to the oxidation tower 1 at a rate of 0-20L / min, and the liquid level of the liquid inside the gas-liquid separator 2 is maintained at 30-65%; wherein, the reading of the oxygen analysis device is controlled to be maintained at 6-8% during the oxidation reaction.

[0088] Example 1

[0089] Based on the above-mentioned isopropylbenzene oxidation reaction system and implementation method, the reaction liquid is an isopropylbenzene mixed liquid containing 3% isopropylbenzene hydroperoxide, the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 90°C, the surface pressure inside the oxidation tower 1 is maintained at 0, air is introduced into the oxidation tower 1 at a rate of 2L / min, and the liquid inside the gas-liquid separator is circulated into the oxidation tower 1 at a rate of 2L / min. After the reaction lasts for 6 hours, the liquid sample is analyzed by liquid chromatography and indirect iodine titration.

[0090] According to the test, the generation rate of CHP is 1.45% / h and the selectivity is 95.5%.

[0091] Example 2

[0092] The process was carried out with reference to Example 1, except that the reaction solution was a cumene mixture containing 5% cumene hydroperoxide.

[0093] According to the test, the generation rate of CHP is 1.55% / h and the selectivity is 95.2%.

[0094] Example 3

[0095] The process was carried out with reference to Example 1, except that the reaction solution was a cumene mixture containing 8% cumene hydroperoxide.

[0096] According to the test, the generation rate of CHP is 1.68% / h and the selectivity is 95.2%.

[0097] Example 4

[0098] The process was carried out with reference to Example 1, except that the reaction solution was a cumene mixture containing 10% cumene hydroperoxide.

[0099] According to the detection, the generation rate of CHP is 1.72% / h and the selectivity is 95.0%.

[0100] Example 5

[0101] The process was carried out with reference to Example 1, except that the reaction solution was a cumene mixture containing 15% cumene hydroperoxide.

[0102] According to the test, the generation rate of CHP is 1.75% / h and the selectivity is 94.5%.

[0103] Example 6

[0104] The method is implemented with reference to Example 3, except that the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 100°C.

[0105] According to the test, the generation rate of CHP is 1.83% / h and the selectivity is 95.3%.

[0106] Example 7

[0107] The method is implemented with reference to Example 6, except that the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 110°C.

[0108] According to the test, the generation rate of CHP is 1.95% / h and the selectivity is 94.6%.

[0109] Example 8

[0110] The method is implemented with reference to Example 6, except that the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 120°C.

[0111] According to the detection, the generation rate of CHP is 1.90% / h and the selectivity is 94.0%.

[0112] Example 9

[0113] The method is implemented with reference to Example 6, except that the temperature inside the oxidation tower 1 and the temperature inside the gas-liquid separator 2 are raised to 130°C.

[0114] According to the test, the generation rate of CHP is 1.72% / h and the selectivity is 92.2%.

[0115] Example 10

[0116] The method is implemented with reference to Example 6, except that air is introduced into the oxidation tower 1 at a rate of 2 L / min, and the liquid in the gas-liquid separator is circulated into the oxidation tower 1 at a rate of 4 L / min.

[0117] According to the detection, the generation rate of CHP is 1.87% / h and the selectivity is 95.0%.

[0118] Embodiment 11

[0119] The method is implemented with reference to Example 6, except that the air is introduced into the oxidation tower 1 at a rate of 2 L / min, and the liquid in the gas-liquid separator is circulated into the oxidation tower 1 at a rate of 1 L / min.

[0120] According to the test, the generation rate of CHP is 1.80% / h and the selectivity is 95.1%.

[0121] Example 12

[0122] The method is implemented with reference to Example 10, except that the gauge pressure inside the oxidation tower 1 is maintained at 0.2 MPa.

[0123] According to the test, the generation rate of CHP is 2.02% / h and the selectivity is 93.6%.

[0124] Example 13

[0125] The method is implemented with reference to Example 10, except that the gauge pressure inside the oxidation tower 1 is maintained at 0.3 MPa.

[0126] According to the test, the generation rate of CHP is 2.15% / h and the selectivity is 93.3%.

[0127] Embodiment 14

[0128] The method is implemented with reference to Example 10, except that the gauge pressure inside the oxidation tower 1 is maintained at 0.4 MPa.

[0129] According to the test, the generation rate of CHP is 2.21% / h and the selectivity is 92.3%.

[0130] Further, based on the above Examples 1-14, the data results are shown in Table 1 below.

[0131] Table 1

[0132]

[0133] As can be seen from Table 1 above, by using the system described in the present invention, the oxidation efficiency of cumene is effectively improved by further optimizing the concentration of cumene hydroperoxide in the reaction liquid (i.e., CHP initiator concentration), the temperature inside the oxidation tower and the gas-liquid separator (i.e., reaction temperature), the gauge pressure inside the oxidation tower (i.e., reaction gauge pressure), and the introduction rate of gas and reaction liquid (i.e., gas-liquid ratio). Ultimately, the optimal values ​​of CHP generation rate and selectivity are obtained, that is, the CHP generation rate is 2.15% / h, and the selectivity is 93.3%. Specifically, as shown in Example 13, at this time, the concentration of cumene hydroperoxide in the reaction liquid is 8%, the temperature inside the oxidation tower and the gas-liquid separator is 100°C, the gauge pressure inside the oxidation tower is 0.3MPa, and the gas-liquid ratio is 1:2.

[0134] The cumene oxidation reaction system and method provided by the present invention oxidizes cumene through the oxidation tower, separates gas and liquid through the gas-liquid separator, recovers cumene components in the gas through the condensing equipment, and circulates the liquid into the oxidation tower through the circulation equipment, which can effectively improve the oxidation efficiency of cumene, and has the advantages of high cumene hydroperoxide generation rate, high selectivity and high safety. Furthermore, by using the oxygen analysis equipment in conjunction with the gas supply equipment, it can further effectively prevent the oxygen concentration at the top of the gas-liquid separator from being too high and from combusting and exploding with the cumene gas component, which has the advantage of higher safety.

[0135] The preferred embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A cumene oxidation reaction system, characterized in that: The system comprises an oxidation tower (1) and a gas-liquid separator (2); The interior of the oxidation tower (1) is provided with a bubbling reactor (12) and a micro-bubble generator (11) in sequence from top to bottom; the bottom of the oxidation tower (1) is connected to a gas supply device and a liquid supply device respectively, and the top is connected to the gas-liquid separator (2); the top of the gas-liquid separator (2) is connected to a condensation device (5) and the gas supply device respectively, and the condensation device (5) is connected to an oxygen analysis device (6); a liquid circulation device is provided between the bottom of the gas-liquid separator (2) and the bottom of the oxidation tower (1), and is used to circulate the liquid inside the gas-liquid separator (2) to the inside of the micro-bubble generator (11).

2. The system according to claim 1, characterized in that The microbubble generator (11) is a ceramic membrane microbubble generator.

3. The system according to claim 2, characterized in that The ceramic membrane of the ceramic membrane microbubble generator has an average pore size of 10 nm to 10 μm, a porosity of 30 to 35%, and a transmembrane pressure difference of 0.2 to 0.5 MPa.

4. The system according to any one of claims 1 to 3, characterized in that: The oxidation tower (1) further comprises a first heating device (13) for maintaining the temperature inside the oxidation tower (1) at 90-130°C during the cumene oxidation reaction.

5. The system according to claim 4, characterized in that The gas-liquid separator (2) further comprises a second heating device (21) for maintaining the temperature inside the gas-liquid separator (2) at 90-130° C. during the cumene oxidation reaction.

6. The system according to claim 1 or 5, characterized in that: The condensation device (5) comprises a condensation tank (51) and a circulation cooler (52) arranged on the condensation tank (51), and the circulation cooler (52) is used to maintain the temperature inside the condensation tank (51) at 20-40°C.

7. The system according to claim 6, characterized in that The bottom of the condensation tank (51) is connected to the top of the gas-liquid separator (2), and the top is connected to the oxygen analysis device (6). A metal wire mesh corrugated filler (511) is arranged inside the condensation tank (51).

8. The system according to claim 1 or 7, characterized in that: The system also includes a reaction pressure control device for maintaining the internal gauge pressure of the oxidation tower (1) at 0-0.4 MPa during the cumene oxidation reaction.

9. The system according to claim 1, characterized in that The step of circulating the liquid in the gas-liquid separator (2) to the interior of the microbubble generator (11) specifically includes: During the cumene oxidation reaction, the liquid inside the gas-liquid separator (2) is circulated and transported to the inside of the microbubble generator (11) at a rate of 0-20 L / min, and the liquid level inside the gas-liquid separator (2) is maintained at 30-65%.

10. The system according to claim 1 or 9, characterized in that: The gas supply device is used to transport protective gas and / or reaction gas to the interior of the microbubble generator (11), and is used to transport protective gas to the top of the gas-liquid separator (2).

11. The system according to claim 10, characterized in that The gas supply device is used to introduce reaction gas into the interior of the microbubble generator (11) at a rate of 0-5 L / min during the cumene oxidation reaction.

12. The system according to claim 10 or 11, characterized in that The protective gas is an inert gas, and the reactive gas is air.

13. The system according to claim 10, characterized in that A preheater (4) is provided between the gas supply equipment and the oxidation tower (1).

14. The system according to claim 1, characterized in that The liquid supply device is used to introduce a reaction liquid into the interior of the microbubble generator (11), wherein the reaction liquid is a cumene mixed liquid containing 0-15% cumene hydroperoxide.

15. A method for oxidation of cumene, characterized in that: The method is implemented using the system described in any one of claims 1 to 14, wherein the method comprises the following steps: S1, the liquid supply device transports the reaction liquid into the oxidation tower (1), and when the interior of the oxidation tower (1) is filled with the reaction liquid and the liquid level of the reaction liquid inside the gas-liquid separator (2) reaches 20-30%, the reaction liquid is stopped from being transported into the oxidation tower (1); S2, the liquid circulation device circulates the liquid in the gas-liquid separator (2) into the oxidation tower (1), and maintains the liquid level in the gas-liquid separator (2) at 20-60%; S3, the protective gas preheated to 80-90° C. by the preheater (4) is introduced into the oxidation tower (1), the first heating device (13) maintains the temperature inside the oxidation tower (1) at 80-90° C., the second heating device (21) maintains the temperature inside the gas-liquid separator (2) at 80-90° C., and the circulating cooler (52) maintains the internal temperature of the condensation tank (51) at 20-40° C.; S4, after the bubble flow in the oxidation tower (1) is stable, the temperature inside the oxidation tower (1) and the temperature inside the gas-liquid separator (2) are both stable at 80-90° C., and the liquid level inside the gas-liquid separator (2) is stable at 20-60%, the temperature inside the oxidation tower (1) and the temperature inside the gas-liquid separator (2) are raised to 90-130° C.; S5. The reaction pressure control device is used to maintain the internal gauge pressure of the oxidation tower (1) at 0-0.4 MPa; the reaction gas preheated to 80-90° C. by the preheater (4) is introduced into the oxidation tower (1) at a rate of 0-5 L / min, and the feed rate of the protective gas is reduced to zero, and at the same time, the liquid in the gas-liquid separator (2) is circulated to the oxidation tower (1) at a rate of 0-20 L / min, and the liquid level in the gas-liquid separator (2) is maintained at 30-65%; wherein, during the oxidation reaction, the reading of the oxygen analysis device (6) is controlled to always remain at 6-9.5%.

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