Fixed bed reactor and application, hydrogenation method for preparing hydrogen peroxide by anthraquinone method, device and method for preparing hydrogen peroxide by anthraquinone method

Abstract

The present application relates to the technical field of hydrogen peroxide, in particular to a fixed bed reactor and application, a hydrogenation method for preparing hydrogen peroxide by anthraquinone method, and a device and method for preparing hydrogen peroxide by anthraquinone method. The fixed bed reactor comprises a reactor cylinder, a liquid phase inlet, N gas phase inlets, a liquid phase outlet and a gas phase outlet arranged on the reactor cylinder in sequence from bottom to top, and N catalyst bed layers and a gas-liquid separation component arranged in the reactor cylinder in sequence from bottom to top; N is a natural number and N is greater than or equal to 2; a gas distributor is arranged below each catalyst bed layer, and the gas distributor is connected with the gas phase inlet; the gas-liquid separation component is divided into a two-phase zone, a liquid phase zone and a gas phase zone; the liquid phase zone is provided with the liquid phase outlet; and the gas phase zone is provided with the gas phase outlet. The fixed bed reactor can strengthen gas-liquid mass transfer, improve catalyst bed utilization, reduce bed temperature rise, and further improve reaction selectivity.

Description

Technical Field

[0001] This invention relates to the field of hydrogen peroxide technology, specifically to a fixed-bed reactor and its application, a hydrogenation method for preparing hydrogen peroxide using the anthraquinone process, and an apparatus and method for preparing hydrogen peroxide using the anthraquinone process. Background Technology

[0002] The anthraquinone process is the mainstream method for industrial hydrogen peroxide production, accounting for over 99% of global industrial hydrogen peroxide production by output. The anthraquinone process includes steps such as hydrogenation, oxidation, extraction, and post-treatment of the circulating working fluid. The efficiency of anthraquinone hydrogenation directly affects the efficiency of the entire production unit and the product concentration. The "hydrogen efficiency" is typically used to characterize anthraquinone hydrogenation efficiency, which is the number of grams of hydrogen peroxide per liter of the hydrogenation reaction liquid (called the "hydrogenation liquid"). Domestic hydrogen peroxide production technology uses a trickle bed hydrogenation process, which generally has a hydrogen efficiency of only 6-7 g / L, resulting in low unit production efficiency. The main reason for this is that in the trickle bed reactor, hydrogen gas is the continuous phase, and the reaction liquid (called the "working liquid") is the dispersed phase, making it easy for flow deviation or channeling to occur within the bed. This leads to localized over-hydrogenation and hot spots within the bed, and also results in a high temperature rise within the bed. The main consequences are as follows:

[0003] (1) The catalyst is easily deactivated and must be regenerated or replaced regularly, which not only consumes steam, but also causes loss of working fluid and precious metals in the catalyst. At present, in the fixed bed hydrogenation process in China, the catalyst needs to be regenerated with steam once every 3-6 months.

[0004] (2) In order to prevent excessive hydrogenation, the anthraquinone conversion rate is usually controlled at a relatively low level (30-40%), which limits hydrogen efficiency and reduces the efficiency of the unit. Compared with the same scale unit with high hydrogen efficiency, the circulating working fluid volume is larger and the power consumption of pumps is greater.

[0005] (3) The working fluid is easily degraded. In industry, a large amount of activated alumina is used to continuously regenerate the circulating working fluid. The activated alumina needs to be replaced frequently, generating a large amount of solid hazardous waste and causing loss of working fluid. For example, producing 1 ton of hydrogen peroxide product requires 5 kg of activated alumina, which will result in a loss of 3 kg of working fluid.

[0006] (4) The device has poor safety and requires the use of a potassium carbonate drying tower to remove saturated water from the circulating working fluid and enhance the regeneration of the working fluid. Since hydrogen peroxide decomposes when it comes into contact with alkali, it poses a serious safety hazard. Every year, there are safety accidents in the hydrogen peroxide device, and 80% of the safety accidents are caused by the system being exposed to alkali in the oxidation and extraction units.

[0007] CN104843648A discloses a fixed-bed hydrogenation reaction system for producing hydrogen peroxide using the anthraquinone process. A nozzle at the top of the hydrogenation tower serves as the working liquid inlet, and hydrogen gas also enters from the top of the reactor via a distributor. To improve the uniformity of gas-liquid distribution within the reactor and reduce the temperature rise of the reactor bed, this hydrogenation reaction system incorporates a heat exchanger layer and a gas-liquid distributor between the catalyst layers. However, this reactor has a complex structure, and the built-in heat exchanger poses a risk of leakage, potentially leading to catalyst deactivation.

[0008] CN1480390A discloses a fixed-bed reactor for hydrogenating anthraquinone working fluid in hydrogen peroxide production. This reactor also features a working fluid sprayer at the top of the reactor shell. To improve gas-liquid contact and mixing within the reactor, the reactor is filled with alternating layers of packing material and catalyst from top to bottom. However, due to the multi-layered packing, this reactor requires increased reactor height and pump energy consumption. Simultaneously, the pressure drop in the reactor also increases significantly, and the catalyst and fine catalyst powder easily clog the packing material, further increasing the reactor pressure drop. Summary of the Invention

[0009] The purpose of this invention is to overcome the problems of low equipment efficiency, low hydrogenation efficiency, easy catalyst deactivation, poor safety, complex structure, and poor economy caused by local over-hydrogenation and local hot spots in the reactor bed in existing hydrogen peroxide processes. This invention provides a fixed-bed reactor and its application, a hydrogenation method for preparing hydrogen peroxide using the anthraquinone process, and an apparatus and method for preparing hydrogen peroxide using the anthraquinone process. This fixed-bed reactor essentially eliminates local over-hydrogenation and local hot spots in the catalyst bed, thereby extending catalyst life and improving equipment efficiency. Furthermore, using this fixed-bed reactor in the anthraquinone process for hydrogen peroxide preparation can effectively improve the selectivity and efficiency of the hydrogenation reaction.

[0010] To achieve the above objectives, the first aspect of the present invention provides a fixed-bed reactor, the fixed-bed reactor comprising: a reactor body, a liquid phase inlet, N gas phase inlets, a liquid phase outlet and a gas phase outlet arranged sequentially from bottom to top on the reactor body, and N catalyst bed layers and a gas-liquid separation component arranged sequentially from bottom to top within the reactor body; wherein, N is a natural number and N≥2;

[0011] A gas distributor is provided below each section of the catalyst bed, and the gas distributor is connected to the gas inlet.

[0012] The gas-liquid separation component is divided into a two-phase region, a liquid phase region, and a gas phase region; the liquid phase region is provided with a liquid phase outlet; and the gas phase region is provided with a gas phase outlet.

[0013] Preferably, the gas-liquid separation component includes a separation component cylinder, and a baffle, an overflow pipe, and an anti-impact baffle disposed within the separation component cylinder.

[0014] Preferably, the area formed by the overflow pipe and the anti-impact baffle is the two-phase region; the area formed by the baffle and the inner wall of the separator cylinder is the liquid phase region; and the area formed by the anti-impact baffle and the inner wall of the separator cylinder is the gas phase region.

[0015] Preferably, the fixed-bed reactor further includes (N-1) circulating liquid phase inlets connected to the liquid phase outlet, and each of the circulating liquid phase inlets is independently arranged on the reactor body.

[0016] Preferably, from bottom to top, the second to the Nth segment, each segment of the catalyst bed has its own independently provided circulating liquid phase inlet below it.

[0017] The second aspect of the present invention provides an application of the fixed-bed reactor provided in the first aspect in a hydrogenation reaction, preferably in the hydrogenation reaction for the preparation of hydrogen peroxide using the anthraquinone process.

[0018] A third aspect of the present invention provides a hydrogenation method for preparing hydrogen peroxide using the anthraquinone process, wherein the hydrogenation method is carried out in a fixed-bed reactor provided in the first aspect;

[0019] The hydrogenation method includes: hydrogen-containing gas entering the reactor cylinder through N gas phase inlets, then being dispersed into hydrogen-containing gas bubbles by N gas distributors, and then contacting the working liquid entering the reactor cylinder through the liquid phase inlet, and then independently undergoing hydrogenation reactions in N catalyst bed sections. The resulting reaction products flow upward into the gas-liquid separation unit for gas-liquid separation, the resulting hydrogenated liquid flows out through the liquid phase outlet, and the resulting hydrogen-containing tail gas is discharged through the gas phase outlet.

[0020] Preferably, the hydrogenation reaction process includes:

[0021] 1) The hydrogen-containing gas bubbles that pass through the first gas phase inlet and the first gas distributor come into first contact with the working fluid and then enter the first catalyst bed to carry out the first hydrogenation reaction to obtain the first reaction product;

[0022] 2) The hydrogen-containing gas bubbles passing through the second gas inlet and the second gas distributor come into a second contact with the first reaction product and then enter the second catalyst bed to carry out a second hydrogenation reaction to obtain the second reaction product;

[0023] 3) The hydrogen-containing gas bubbles passing through the Nth gas phase inlet and the Nth gas distributor come into contact with the (N-1)th reaction product for the Nth time, and then enter the Nth catalyst bed to carry out the Nth hydrogenation reaction to obtain the reaction product.

[0024] A fourth aspect of the present invention provides an apparatus for preparing hydrogen peroxide by anthraquinone method, the apparatus comprising: the fixed-bed reactor, the oxidation reactor, and the extraction tower provided in the first aspect, connected in sequence;

[0025] The fixed-bed reactor is used to perform a hydrogenation reaction between the working fluid and the hydrogen-containing gas, and the reaction products are separated into a hydrogenated liquid and a hydrogen-containing tail gas.

[0026] The oxidation reactor is connected to the liquid phase outlet of the fixed-bed reactor and is used to oxidize the hydrogenated liquid to obtain an oxidized liquid rich in hydrogen peroxide.

[0027] The extraction tower is connected to the outlet of the oxidation reactor and is used to extract the hydrogen peroxide-rich oxidation liquid to obtain a hydrogen peroxide solution and raffinate.

[0028] A fifth aspect of the present invention provides a method for preparing hydrogen peroxide using anthraquinone, the method being carried out in the apparatus provided in the fourth aspect; wherein the method includes the following steps:

[0029] (1) The working fluid and hydrogen-containing gas are subjected to hydrogenation reaction, and the reaction products are separated into gas and liquid to obtain hydrogenated liquid and hydrogen-containing tail gas.

[0030] (2) The hydrogenated liquid is subjected to an oxidation reaction to obtain an oxidized liquid rich in hydrogen peroxide;

[0031] (3) Extract the hydrogen peroxide-rich oxidizing liquid to obtain a hydrogen peroxide solution and a raffinate.

[0032] Compared with the prior art, the present invention has the following advantages:

[0033] (1) The fixed bed reactor provided by the present invention is a gas-liquid co-flow upflow reactor. The catalyst in the N-section (N is a natural number and N≥2) catalyst bed is immersed in the liquid phase. The gas distributor installed under each section of the catalyst bed can disperse the gas phase into tiny bubbles, so that the gas and liquid phases can be in uniform contact in the catalyst bed, enhance gas-liquid mass transfer, improve the utilization rate of the catalyst bed, basically eliminate channeling and bias flow in the bed, as well as the resulting local over-hydrogenation and local hot spots;

[0034] (2) The fixed-bed reactor provided by the present invention is provided with N catalyst bed layers. Each catalyst bed layer is provided with a gas distributor below it. The gas phase enters the reactor cylinder in multiple streams according to the number of catalyst bed layers. This can prevent the already formed micro bubbles from accumulating in the catalyst and reduce the gas-liquid mass transfer effect. In particular, from bottom to top, the second to the Nth catalyst bed layers are provided with a circulating liquid phase inlet below each catalyst bed layer to remove the heat of reaction and reduce the temperature rise of the bed.

[0035] (3) The fixed bed reactor provided by the present invention integrates multiple functions such as reaction, gas-liquid mass transfer, gas-liquid separation and heat extraction. It has a simple and compact structure, is easy to operate, occupies a small area, reduces material consumption, energy consumption and production costs, and improves the inherent safety of the device.

[0036] (4) The fixed-bed reactor provided by the present invention has superior mass and heat transfer performance and can be used for hydrogenation reactions, especially for hydrogenation reactions in the anthraquinone process to prepare hydrogen peroxide. It can improve the selectivity, hydrogen efficiency and equipment efficiency of the hydrogenation reaction. In particular, the hydrogen efficiency can be improved to 8.0-10 g / L, or even above 10 g / L, reducing the amount of circulating working fluid and reducing energy consumption; extending the life of the hydrogenation catalyst and reducing the consumption caused by catalyst regeneration; reducing the amount of regenerated working fluid and reducing the consumption caused by working fluid regeneration and the amount of solid waste generated; eliminating the need for working fluid regeneration in the alkali tower and improving the inherent safety of the equipment. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of a fixed-bed reactor provided by the present invention;

[0038] Figure 2 This is a schematic diagram of an apparatus for preparing hydrogen peroxide using the anthraquinone method provided by the present invention;

[0039] Explanation of reference numerals in the attached figures

[0040] I. Fixed-bed reactor; II. Compressor; III. Circulating liquid cooler; IV. Gas flow controller

[0041] V. Liquid flow controller; VI. Pressure controller; VII. Liquid level controller

[0042] VIII, Oxidation Reactor IX, Extraction Tower X, Gas Flow Control Valve XI, Liquid Flow Control Valve

[0043] XII, Pressure regulating valve; XIII, Liquid level regulating valve

[0044] 1. Reactor shell 2. Liquid phase inlet 3. Gas phase inlet 4. Gas phase outlet

[0045] 5. Liquid phase outlet; 6. Catalyst bed; 7. Gas distributor; 8. Separation component cylinder.

[0046] 9. Baffle plate; 10. Overflow pipe; 11. Anti-surge baffle; 12. Circulating liquid phase inlet.

[0047] 13. Liquid distributor

[0048] 01. Hydrogen-containing gas; 02. Working fluid; 03. Hydrogenated liquid; 04. Hydrogen-containing exhaust gas.

[0049] 05. Pressurized hydrogen-containing exhaust gas; 06. Partial hydrogenated liquid; 07. Cooling hydrogenated liquid; 08. Oxidizing liquid.

[0050] 09. Hydrogen peroxide solution; 010. Raffinate Detailed Implementation

[0051] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0052] In this invention, unless otherwise specified, the top of the tower body refers to 0-10% of the tower body from top to bottom; the upper part of the tower body refers to 10-40% of the tower body from top to bottom; the middle part of the tower body refers to 40-60% of the tower body from top to bottom; the lower part of the tower body refers to 60-90% of the tower body from top to bottom; and the bottom of the tower body refers to 90-100% of the tower body from top to bottom.

[0053] In this invention, unless otherwise specified, "first," "second," and "Nth" do not indicate a sequence or limit the various materials or steps; they are merely used to distinguish or indicate that these are not the same material or step. For example, in "first contact," "second contact," and "Nth contact," "first," "second," and "Nth" are only used to indicate that these are not the same contact.

[0054] The first aspect of the present invention provides a fixed-bed reactor, the fixed-bed reactor comprising: a reactor body, a liquid phase inlet, N gas phase inlets, a liquid phase outlet and a gas phase outlet arranged sequentially from bottom to top on the reactor body, and N catalyst bed layers and a gas-liquid separation component arranged sequentially from bottom to top within the reactor body; wherein, N is a natural number and N≥2;

[0055] A gas distributor is provided below each section of the catalyst bed, and the gas distributor is connected to the gas inlet.

[0056] The gas-liquid separation component is divided into a two-phase region, a liquid phase region, and a gas phase region; the liquid phase region is provided with a liquid phase outlet; and the gas phase region is provided with a gas phase outlet.

[0057] In this invention, unless otherwise specified, the number of specific components in the fixed-bed reactor is one, except for components with a clearly defined number; for example, the number of liquid phase inlet is one; similarly, the number of gas-liquid separation components is also one.

[0058] In this invention, unless otherwise specified, the liquid phase inlet, N gas phase inlets, liquid phase outlet and gas phase outlet arranged sequentially on the reactor cylinder from bottom to top refer to the liquid phase inlet, the first gas phase inlet, the second gas phase inlet, ... the (N-1)th gas phase inlet, the Nth gas phase inlet, the liquid phase outlet and the gas phase outlet being arranged sequentially on the reactor cylinder from bottom to top along the height of the reactor cylinder.

[0059] In this invention, unless otherwise specified, the N-section catalyst bed and gas-liquid separation component arranged sequentially from bottom to top in the reactor cylinder refers to the reactor cylinder having, from bottom to top, a first catalyst bed, a second catalyst bed, ..., an (N-1)th catalyst bed, an Nth catalyst bed, and a gas-liquid separation component arranged sequentially from bottom to top.

[0060] In this invention, the catalyst bed has at least two segments. Preferably, the catalyst bed has 2-8 segments, more preferably 3-5 segments, for example, 3, 4, or 5 segments. In this invention, the type of catalyst packed in the catalyst bed is subject to a wide range of selection; it can be a conventional fixed-bed catalyst, such as a spherical or strip-shaped supported catalyst. This invention does not limit the type of catalyst used.

[0061] In some embodiments of the present invention, preferably, the height-to-diameter ratio of the catalyst bed is 1:0.5-5, for example, 1:0.5, 1:0.8, 1:1, 1:1.5, 1:2, 1:3, and any value within the range of any two values, preferably 1:0.8-3. This is to avoid gas flow deviation or bubble aggregation that could affect the reaction effect and selectivity.

[0062] In some embodiments of the present invention, preferably, the height-to-diameter ratio of the reactor cylinder is 3-30:1, for example, 3:1, 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, and any value within the range of any two values, preferably 5-20:1. Wherein, the height-to-diameter ratio is the ratio of the height of the reactor cylinder to its inner diameter.

[0063] In some embodiments of the present invention, preferably, the height ratio of each section of the catalyst bed to the reactor cylinder is 1:3-20, for example, 1:3, 1:4, 1:5, 1:8, 1:10, 1:12, 1:15, 1:20, and any value within the range of any two values, preferably 1:4-15.

[0064] In some embodiments of the present invention, preferably, the height ratio of the gas-liquid separation component to the reactor cylinder is 1:3-30, for example, 1:3, 1:4, 1:5, 1:8, 1:10, 1:12, 1:15, 1:20, 1:25, 1:30, and any value within the range of any two values, preferably 1:4-15.

[0065] In this invention, unless otherwise specified, the number of catalyst bed segments, the number of gas distributors, and the number of gas phase inlets are the same. That is, an N-segment catalyst bed corresponds to N gas distributors and N gas phase inlets, where N is a natural number and N≥2.

[0066] In this invention, in each catalyst bed segment, the gas phase inlet is connected to the gas distributor, and the gas distributor is located below the catalyst bed. Therefore, the gas phase inlet is also located below the catalyst bed. Preferably, the shortest distance d1 between the gas phase inlet and the lower surface of the catalyst bed is 0.1-1.5 m, for example, 0.1, 0.2, 0.3, 0.5, 0.6, 0.8, 1, 1.2, 1.5, and any value within the range of any two values, preferably 0.2-0.8 m.

[0067] In some embodiments of the present invention, preferably, the gas distributor is selected from perforated tubes or microporous elements; more preferably, the pore size of the perforated tube is 0.5-12 mm, for example, 0.5, 1, 2, 3, 5, 6, 8, 10, 12, or any value within the range of any two values, preferably 1-8 mm; the pore size of the microporous element is 0.2-500 μm, for example, 0.2, 0.5, 1, 10, 20, 30, 50, 60, 80, 100, 120, 150, 180, 200, 300, 400, 500, or any value within the range of any two values, preferably 0.5-200 μm. By dispersing the gas phase into tiny bubbles, the gas and liquid phases are uniformly contacted within the catalyst bed, enhancing gas-liquid mass transfer and improving device efficiency.

[0068] In some embodiments of the present invention, preferably, the microporous element is selected from at least one of sintered membrane tubes, sintered membrane plates, metal sintered mesh tubes, and metal sintered mesh plates.

[0069] In this invention, to further enhance gas-liquid mass transfer and improve device efficiency, preferably, a liquid distributor is disposed below each section of the catalyst bed, and the liquid distributor is positioned below the gas distributor. In this invention, the type of liquid distributor is not limited, and the liquid distributor includes, but is not limited to, a tubular distributor.

[0070] In a preferred embodiment of the present invention, the liquid distributor can be shared with the gas distributor.

[0071] In some embodiments of the present invention, preferably, the gas-liquid separation component includes a separation component cylinder, and a baffle, an overflow pipe, and an anti-impact baffle disposed within the separation component cylinder; more preferably, the area formed by the overflow pipe and the anti-impact baffle is the two-phase region; the area formed by the baffle and the inner wall of the separator cylinder is the liquid phase region; and the area formed by the anti-impact baffle and the inner wall of the separator cylinder is the gas phase region.

[0072] In some embodiments of the present invention, preferably, the ratio of the inner diameter of the separation component cylinder and the reactor cylinder is 0.2-1.5:1, for example, 0.2:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.2:1, 1.5:1, and any value within the range of any two values, preferably 0.5-1:1.

[0073] In this invention, unless otherwise specified, 1:1 < when the ratio of the inner diameters of the separating component cylinder and the reactor cylinder is ≤1.5:1, that is, the separating component cylinder is an expanded diameter section relative to the straight section of the reactor cylinder; 0.2:1 ≤ when the ratio of the inner diameters of the separating component cylinder and the reactor cylinder is <1:1, that is, the separating component cylinder is a reduced diameter section relative to the straight section of the reactor cylinder; when the ratio of the inner diameters of the separating component cylinder and the reactor cylinder is 1:1, the separating component cylinder and the reactor cylinder are straight cylinder sections with equal inner diameters.

[0074] In some embodiments of the present invention, preferably, the included angle α between the partition and the separation component cylinder is 45°-90°, and the included angle β between the partition and the overflow pipe is 90°-145°.

[0075] In some embodiments of the present invention, preferably, the inner diameter ratio of the overflow pipe and the separation component cylinder is 0.15-0.75:1, for example, 0.15:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.75:1, or any of any two values ​​within a range, preferably 0.2-0.6:1. This configuration, by adjusting the range of the two-phase region and the liquid phase region, is more conducive to promoting gas-liquid separation and obtaining the hydrogenation reaction product, i.e., the hydrogenated liquid.

[0076] In some embodiments of the present invention, preferably, the height ratio of the overflow pipe to the separation component cylinder is 0.2-0.95:1, for example, 0.2:1, 0.3:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.95:1, or any of any two values ​​within a range, preferably 0.5-0.8:1. This configuration, by adjusting the range of the two-phase region and the gas phase region, is more conducive to promoting gas-liquid separation and obtaining hydrogen-containing tail gas.

[0077] In some embodiments of the present invention, preferably, the cross-section of the overflow pipe is a regular shape, preferably selected from at least one of quadrilateral, trapezoid, arc and circle, and preferably circular.

[0078] In some embodiments of the present invention, preferably, the anti-rush baffle is disposed above the overflow pipe; more preferably, the shortest distance between the lower edge of the anti-rush baffle and the upper end of the overflow pipe is 0.3-1.2m, for example, 0.3, 0.5, 0.6, 0.8, 1, 1.2, and any value in the range of any two values, preferably 0.3-0.8m.

[0079] In this invention, the structure of the anti-impact baffle is not limited. Preferably, the anti-impact baffle is a conical structure; more preferably, the anti-impact baffle is a conical structure, with an included angle γ of 110°-145°. This configuration can effectively prevent gas-liquid two-phase splashing in the two-phase region and improve the gas-liquid separation effect.

[0080] According to the present invention, preferably, the liquid phase inlet is located at the bottom of the reactor body, and the gas phase outlet is located at the top of the reactor body.

[0081] In some embodiments of the present invention, preferably, a liquid flow controller and a liquid flow regulating valve are provided on the pipe connected to the liquid inlet.

[0082] According to the present invention, preferably, the gas phase outlet is connected to N gas phase inlets; more preferably, a compressor is provided on the pipeline connecting the gas phase outlet and the gas phase inlets.

[0083] According to the present invention, preferably, a gas flow controller is provided on the pipe of each gas phase inlet; more preferably, a gas flow regulating valve is provided on the pipe connecting the gas phase inlet and the gas flow controller, and the gas flow regulating valve is located between the gas phase inlet and the gas flow controller. This configuration allows for the regulation of the gas-liquid contact within the catalyst bed by adjusting the gas flow rate at each gas phase inlet according to reaction requirements, thereby enhancing liquefaction mass transfer, eliminating channeling and flow deviation within the catalyst bed, and preventing localized over-hydrogenation and localized hot spots.

[0084] According to the present invention, preferably, the fixed-bed reactor further includes (N-1) circulating liquid phase inlets connected to the liquid phase outlet, and each of the circulating liquid phase inlets is independently arranged on the reactor body.

[0085] According to the present invention, more preferably, from bottom to top, the second to the Nth segment, each segment of the catalyst bed is independently provided with a circulating liquid phase inlet below it.

[0086] In some embodiments of the present invention, preferably, from bottom to top, the (N-1)th circulating liquid phase inlet is located below the Nth gas phase inlet.

[0087] In some embodiments of the present invention, preferably, the shortest distance d2 between the circulating liquid phase inlet and the bottom of the catalyst bed is 0.2-1.2m, for example, 0.2, 0.3, 0.5, 0.6, 0.8, 1, 1.2, and any value in the range of any two values, preferably 0.3-0.8m.

[0088] In some embodiments of the present invention, preferably, a circulating liquid cooler is provided on the pipe connecting the circulating liquid inlet and the liquid outlet. This cooler is used to remove the heat of reaction, reduce the temperature rise of the catalyst bed, improve reaction selectivity, and thus improve the reaction conversion rate and device efficiency.

[0089] In this invention, to regulate the flow rate of the circulating liquid phase, preferably, a liquid flow controller is also provided on the pipe connecting the circulating liquid phase inlet and the liquid phase outlet, and the liquid flow controller is located before the circulating liquid cooler.

[0090] In some embodiments of the present invention, preferably, a liquid flow regulating valve is also provided on the pipe connecting the circulating liquid phase inlet and the liquid phase outlet, and the liquid flow regulating valve is located between the liquid flow controller and the circulating cooler.

[0091] In this invention, unless otherwise specified, the liquid flow controller being located before the circulating liquid cooler means that, in accordance with the direction of circulating liquid flow, the liquid flow controller, the liquid flow regulating valve, and the circulating liquid cooler are sequentially installed on the pipes at the liquid phase outlet and the circulating liquid phase inlet.

[0092] In some embodiments of the present invention, preferably, a pressure controller is provided at the top of the reactor shell; more preferably, a pressure regulating valve is provided on the pipe connecting the gas phase outlet and the gas phase inlet. In the present invention, the pressure regulating valve controls the pressure controller.

[0093] In some embodiments of the present invention, preferably, a level controller is provided in the liquid phase zone, and a level regulating valve is provided on the pipe connected to the liquid phase outlet. In the present invention, the level regulating valve controls the level controller.

[0094] A schematic diagram of a fixed-bed reactor provided by this invention is shown below. Figure 1 As shown, by Figure 1 It can be seen that the fixed bed reactor I includes: reactor body 1, liquid phase inlet 2, N gas phase inlets 3 (N=3), gas phase outlet 4, liquid phase outlet 5 and (N-1) circulating liquid phase inlets 12 arranged on the reactor body 1, and N catalyst bed layers 6 and gas-liquid separation components arranged sequentially from bottom to top inside the reactor body 1;

[0095] Among them, a gas distributor 7 and a liquid distributor 13 are arranged in sequence below each catalyst bed 6, and the gas distributor 7 is connected to the gas inlet 3.

[0096] The gas-liquid separation component includes a separation component cylinder 8, and a baffle 9, an overflow pipe 10, and an anti-impact baffle 11 disposed inside the separation component cylinder 8, so that the gas-liquid separation component is divided into a two-phase zone, a liquid phase zone, and a gas phase zone; wherein, the liquid phase zone is provided with a liquid phase outlet 5; and the gas phase zone is provided with a gas phase outlet 4.

[0097] Among them, the included angle α between the baffle 9 and the separation component cylinder 8 is 45-90°; the included angle β between the baffle 9 and the overflow pipe 10 is 90-145°; the anti-impact baffle 11 is arranged above the overflow pipe 10, and the included angle γ is 110-145°.

[0098] Among them, the gas phase outlet 4 is connected to N gas phase inlets 3, and a compressor II is installed on the pipeline connecting the gas phase outlet 4 and the gas phase inlets 3; a gas flow controller IV and a gas flow regulating valve X are installed on the pipeline of each gas phase inlet 3.

[0099] Among them, from bottom to top, the second to the Nth section, each section of catalyst bed 6 is independently provided with a circulating liquid inlet 12 below it; the (N-1)th circulating liquid inlet 12 is located below the Nth gas inlet 3; a liquid flow controller V, a liquid flow regulating valve XI and a circulating liquid cooler III are sequentially provided on the pipe connecting the circulating liquid inlet 12 and the liquid outlet 5.

[0100] The reactor cylinder 1 is equipped with a pressure controller VI at the top, and a pressure regulating valve XII is installed on the pipe connecting the gas phase outlet 4, the gas phase inlet 3 and the pressure controller VI.

[0101] The liquid phase zone is equipped with a liquid level controller VII, and the pipe connected to the liquid phase outlet 5 is equipped with a liquid level regulating valve XIII.

[0102] The second aspect of the present invention provides an application of the fixed-bed reactor provided in the first aspect in a hydrogenation reaction, preferably in the hydrogenation reaction for the preparation of hydrogen peroxide using the anthraquinone process.

[0103] A third aspect of the present invention provides a hydrogenation method for preparing hydrogen peroxide using the anthraquinone process, wherein the hydrogenation method is carried out in a fixed-bed reactor provided in the first aspect;

[0104] The hydrogenation method includes: hydrogen-containing gas entering the reactor cylinder through N gas phase inlets, then being dispersed into hydrogen-containing gas bubbles by N gas distributors, and then contacting the working liquid entering the reactor cylinder through the liquid phase inlet, and then independently undergoing hydrogenation reactions in N catalyst bed sections. The resulting reaction products flow upward into the gas-liquid separation unit for gas-liquid separation, the resulting hydrogenated liquid flows out through the liquid phase outlet, and the resulting hydrogen-containing tail gas is discharged through the gas phase outlet.

[0105] In some embodiments of the present invention, preferably, the hydrogenation reaction process includes:

[0106] 1) The hydrogen-containing gas bubbles that pass through the first gas phase inlet and the first gas distributor come into first contact with the working fluid and then enter the first catalyst bed to carry out the first hydrogenation reaction to obtain the first reaction product;

[0107] 2) The hydrogen-containing gas bubbles passing through the second gas inlet and the second gas distributor come into a second contact with the first reaction product and then enter the second catalyst bed to carry out a second hydrogenation reaction to obtain the second reaction product;

[0108] 3) The hydrogen-containing gas bubbles passing through the Nth gas phase inlet and the Nth gas distributor come into contact with the (N-1)th reaction product for the Nth time, and then enter the Nth catalyst bed to carry out the Nth hydrogenation reaction to obtain the reaction product.

[0109] In this invention, unless otherwise specified, the hydrogen efficiency refers to the amount of hydrogen peroxide, expressed in g / L, that is, the amount of hydrogen peroxide (g) that 1 L of working solution can provide when the oxidation step in the oxidation reactor is completed if the yield of the oxidation step is 100%.

[0110] In this invention, the hydrogen-containing gas can be pure hydrogen, or a mixture of pure hydrogen and an inert gas; wherein, nitrogen is preferably the inert gas; preferably, the hydrogen content in the hydrogen-containing gas is 40-100% by volume. After the system stabilizes, pure hydrogen is continuously added to the reactor according to the amount of hydrogen consumed in the reaction; as inert gas is lost, inert gas is intermittently added to the hydrogenation reactor.

[0111] Typically, the working solution is a solution prepared by dissolving an alkyl anthraquinone compound in an organic solvent. Preferably, the alkyl anthraquinone compound is selected from at least one of 2-alkyl-9,10-anthraquinone (i.e., 2-alkyl anthraquinone), 9,10-dialkyl anthraquinone (i.e., dialkyl anthraquinone), and their respective 5,6,7,8-tetrahydro derivatives. In the 2-alkyl-9,10-anthraquinone, the alkyl group can be a C1-C5 alkyl group, and non-limiting examples include methyl, ethyl, sec-butyl, tert-butyl, tert-pentyl, and isopentyl. In the 9,10-dialkyl anthraquinone, the two alkyl groups can be the same or different, and can be selected from C1-C5 alkyl groups, for example, methyl, ethyl, and tert-butyl. The dialkyl group on the 9,10-dialkyl anthraquinone is, for example, 1,3-dimethyl, 1,4-dimethyl, 2,7-dimethyl, 1,3-diethyl, 2,7-di(tert-butyl), or 2-ethyl-6-tert-butyl.

[0112] In some embodiments of the present invention, preferably, the organic solvent is a mixture of a nonpolar compound and a polar compound. The nonpolar compound may be a petroleum fraction with a boiling point above 140°C, whose main component is an aromatic hydrocarbon (heavy aromatic hydrocarbon) with 9 or more carbon atoms, such as isomers of trimethylbenzene, tetramethylbenzene, tert-butylbenzene, methylnaphthalene, and dimethylnaphthalene. The polar compound is preferably at least one of a saturated alcohol, a carboxylic acid ester, a phosphate ester, and a tetrasubstituted urea. The saturated alcohol is typically C7-C6. 11 Saturated alcohols, non-limiting examples of which include: diisobutylmethanol, 3,5,5-trimethylhexanol, and isohepanol. The carboxylic acid ester is, for example, at least one selected from methylcyclohexyl acetate, heptyl acetate, butyl benzoate, and ethyl heptanoate. The phosphate ester is, for example, at least one selected from trioctyl phosphate, tri-2-ethylbutyl phosphate, tri-2-ethylhexyl phosphate, and tri-n-octyl phosphate. The tetrasubstituted urea is, for example, tetra-n-butylurea.

[0113] In some embodiments of the present invention, when the number of catalyst bed segments N = 3, the flow rate ratio of hydrogen-containing gas at the first, second, and third gas phase inlets from bottom to top is 0.6-0.3:0.5-0.2:0.4-0.1. The flow rate of hydrogen-containing gas can be allocated according to the reaction characteristics and actual needs; in the high conversion region, a low space velocity can be used to enhance the reaction.

[0114] In some embodiments of the present invention, preferably, the conditions for the first hydrogenation reaction, the second hydrogenation reaction, ... and the Nth hydrogenation reaction each independently include: a pressure of 0.03-0.35 MPa, preferably 0.05-0.25 MPa; and a temperature of 40-80°C, preferably 45-65°C.

[0115] In some embodiments of the present invention, preferably, m 3 The ratio of the working liquid to the hydrogenation catalyst (in tons) is 1-50:1, for example, 1:1, 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, 40:1, 50:1, and any value within any range of two such values, preferably 5-30:1; wherein the catalyst bed is filled with the hydrogenation catalyst. In this invention, the amount of the working liquid relative to 1 ton of hydrogenation catalyst is 1-50 ml. 3 Preferably 5-30m 3 .

[0116] In this invention, unless otherwise specified, m 3 The ratio of the amount of working fluid to the amount of hydrogenation catalyst (in tons) refers to the ratio of the amount of working fluid to the total amount of hydrogenation catalyst packed in the N-section catalyst bed.

[0117] This invention does not limit the type of hydrogenation catalyst. Preferably, the hydrogenation catalyst is selected from supported catalysts and / or unsupported catalysts, and more preferably from supported catalysts. More preferably, the supported catalyst comprises a support and an active metal, wherein the active metal is selected from at least one of Group VIII, Group IB, and Group IIB metals, and more preferably from at least one of platinum, rhodium, palladium, cobalt, nickel, ruthenium, copper, and rhenium; the support is selected from at least one of activated carbon, silicon carbide, alumina, silicon oxide, silica, titanium dioxide, zirconium dioxide, magnesium oxide, zinc oxide, calcium carbonate, and barium sulfate, and more preferably from alumina and / or silica.

[0118] In some embodiments of the present invention, preferably, the content of the active metal is 0.01-10 wt%, more preferably 0.01-5 wt%, and more preferably 0.1-2 wt%, based on the total weight of the hydrogenation catalyst.

[0119] In some embodiments of the present invention, preferably, the hydrogenation catalyst has a particle diameter of 0.1-10 mm, more preferably 1-10 mm, and more preferably 2-6 mm.

[0120] In some embodiments of the present invention, preferably, the method further includes: returning the hydrogen-containing exhaust gas as a recirculating gas and mixing it with the hydrogen-containing gas; more preferably, pressurizing the hydrogen-containing exhaust gas to obtain pressurized hydrogen-containing exhaust gas as the recirculating gas.

[0121] In some embodiments of the present invention, preferably, the method further includes: returning a portion of the hydrogenated liquid as a circulating hydrogenated liquid to the reactor cylinder through (N-1) circulating liquid phase inlets; more preferably, subjecting a portion of the hydrogenated liquid to a first cooling, and using the resulting cooled hydrogenated liquid as the circulating hydrogenated liquid.

[0122] In some embodiments of the present invention, preferably, the temperature of the cooling hydrogenation liquid is 15-70°C, more preferably 20-50°C, and even more preferably 35-45°C. This setting reduces the temperature rise of the catalyst bed by lowering the temperature of the circulating hydrogenation liquid.

[0123] In some embodiments of the present invention, preferably, the weight ratio of the circulating hydrogenation liquid to the hydrogenation liquid is 10-80:100, for example, 10:100, 15:100, 20:100, 30:100, 40:100, 50:100, 60:100, 80:100, and any value within any range of any two values, preferably 15-60:100, more preferably 15-50:100. This configuration, while reducing the temperature rise of the catalyst bed and ensuring the heat extraction effect of the fixed-bed reactor, minimizes the amount of circulating hydrogenation liquid, thus reducing energy consumption. On the one hand, it can extend the catalyst life and reduce the consumption caused by catalyst regeneration; it can reduce the regeneration load of the working fluid, reducing the consumption caused by working fluid regeneration and the amount of solid waste generated; and it can eliminate the need for working fluid regeneration in the alkali tower, improving the inherent safety of the device.

[0124] In this invention, unless otherwise specified, the hydrogenation liquid includes: a partial hydrogenation liquid and a remaining partial hydrogenation liquid, that is, the hydrogenation liquid includes a circulating hydrogenation liquid and a remaining partial hydrogenation liquid.

[0125] In some embodiments of the present invention, when the number of catalyst bed sections N = 3, the number of circulating liquid phase inlets is 2, and the flow rate ratio of the circulating liquid phase at the first circulating liquid phase inlet to the second circulating liquid phase inlet is 0.3-0.8:0.2-0.7 from bottom to top. This is beneficial for reducing the reaction temperature rise of each catalyst bed.

[0126] A fourth aspect of the present invention provides an apparatus for preparing hydrogen peroxide by anthraquinone method, the apparatus comprising: the fixed-bed reactor, the oxidation reactor, and the extraction tower provided in the first aspect, connected in sequence;

[0127] The fixed-bed reactor is used to perform a hydrogenation reaction between the working fluid and the hydrogen-containing gas, and the reaction products are separated into a hydrogenated liquid and a hydrogen-containing tail gas.

[0128] The oxidation reactor is connected to the liquid phase outlet of the fixed-bed reactor and is used to oxidize the hydrogenated liquid to obtain an oxidized liquid rich in hydrogen peroxide.

[0129] The extraction tower is connected to the outlet of the oxidation reactor and is used to extract the hydrogen peroxide-rich oxidation liquid to obtain a hydrogen peroxide solution and raffinate.

[0130] In this invention, unless otherwise specified, the fixed-bed reactors are all described in accordance with the above-described limitations. Further details are omitted here.

[0131] In this invention, there is a wide range of choices for the type of oxidation reactor, as long as the oxidation reactor can convert the hydrogenated liquid into an oxidation liquid rich in hydrogen peroxide.

[0132] In this invention, the extraction tower can be any known type of tower, such as a packed tower, sieve plate tower, jet tower, pulsed packed tower, etc. Preferably, a liquid distributor can be installed inside the extraction tower, and the oxidizing liquid and the extractant contact countercurrently within the extraction tower.

[0133] According to the present invention, preferably, the raffinate outlet of the extraction tower is connected to the liquid phase inlet of the fixed-bed reactor for returning the raffinate as a circulating working fluid and mixing it into the working fluid.

[0134] A schematic diagram of an apparatus for preparing hydrogen peroxide using the anthraquinone method provided by this invention is shown below. Figure 2 As shown, by Figure 2 It is known that the apparatus includes: a fixed-bed reactor I, an oxidation reactor VIII, and an extraction tower IX connected in sequence;

[0135] Among them, fixed-bed reactor I is used to hydrogenate working liquid 02 and hydrogen-containing gas 01, and the reaction products are separated into gas and liquid to obtain hydrogenated liquid 03 and hydrogen-containing tail gas 04.

[0136] Oxidation reactor VIII is connected to the liquid phase outlet of fixed-bed reactor I and is used to oxidize hydrogenated liquid 03 to obtain oxidized liquid 08 rich in hydrogen peroxide.

[0137] Extraction tower IX is connected to the outlet of oxidation reactor VIII and is used to extract hydrogen peroxide-rich oxidizing liquid 08 to obtain hydrogen peroxide solution 09 and raffinate 010.

[0138] The raffinate outlet of extraction tower IX is connected to the liquid phase inlet of fixed bed reactor I, which is used to return the raffinate as working fluid 010 and mix it into working fluid 02.

[0139] A fifth aspect of the present invention provides a method for preparing hydrogen peroxide using anthraquinone, the method being carried out in the apparatus provided in the fourth aspect; wherein the method includes the following steps:

[0140] (1) The working fluid and hydrogen-containing gas are subjected to hydrogenation reaction, and the reaction products are separated into gas and liquid to obtain hydrogenated liquid and hydrogen-containing tail gas.

[0141] (2) The hydrogenated liquid is subjected to an oxidation reaction to obtain an oxidized liquid rich in hydrogen peroxide;

[0142] (3) Extract the hydrogen peroxide-rich oxidizing liquid to obtain a hydrogen peroxide solution and a raffinate.

[0143] In this invention, in step (2), the oxidation reaction process includes contacting the hydrogenated liquid flowing out of the fixed bed hydrogenation reactor with oxygen in the oxygen-containing gas and performing an oxidation reaction to obtain an oxidized liquid rich in hydrogen peroxide and an oxygen-containing tail gas, wherein the oxygen-containing tail gas refers to the oxygen-containing gas remaining after the oxidation reaction.

[0144] In some embodiments of the present invention, preferably, the conditions for the oxidation reaction include: a temperature of 30-60°C, more preferably 40-55°C; and a pressure of 0.1-0.5 MPa, more preferably 0.2-0.5 MPa. Using these preferred conditions is more conducive to the oxidation reaction of the hydrogenated liquid, thereby improving the oxidation efficiency.

[0145] In this invention, in step (3), the extraction process includes extracting the hydrogen peroxide-rich oxidizing liquid with an extractant to obtain a hydrogen peroxide solution and a raffinate, wherein the hydrogen peroxide solution refers to an aqueous solution of hydrogen peroxide; the extractant includes, but is not limited to, water.

[0146] In some embodiments of the present invention, preferably, the method further includes: returning the hydrogen-containing exhaust gas as a recirculating gas and mixing it with the hydrogen-containing gas.

[0147] In some embodiments of the present invention, preferably, the method further includes: returning a portion of the hydrogenated liquid as a circulating hydrogenated liquid and performing the hydrogenation reaction; more preferably, subjecting a portion of the hydrogenated liquid to a first cooling, and using the resulting cooled hydrogenated liquid as the circulating hydrogenated liquid. In the present invention, the temperature of the cooled hydrogenated liquid is 15-70°C, preferably 20-50°C, and more preferably 35-45°C.

[0148] In some embodiments of the present invention, preferably, the hydrogenated liquid is subjected to a second cooling before the oxidation reaction to obtain a hydrogenated liquid at a temperature of 40-50°C.

[0149] In one embodiment of the present invention, before the oxidation reaction is carried out, the remaining hydrogenated liquid is subjected to a second cooling to obtain a hydrogenated liquid at a temperature of 40-50°C.

[0150] In some embodiments of the present invention, preferably, the method further includes: returning the raffinate as a circulating working fluid and mixing it into the working fluid; more preferably, subjecting the raffinate to a third cooling, and using the resulting cooled raffinate as a circulating working fluid.

[0151] In some embodiments of the present invention, preferably, the temperature of the cooling raffinate is 15-70°C, more preferably 20-50°C, and even more preferably 35-45°C.

[0152] This invention provides a specific implementation method for preparing hydrogen peroxide using the anthraquinone method. Figure 1-2 The process for preparing hydrogen peroxide using the anthraquinone method, as shown, is carried out in this apparatus.

[0153] The apparatus includes: a fixed-bed reactor I, an oxidation reactor VIII, and an extraction tower IX connected in sequence; the raffinate outlet of the extraction tower IX is connected to the liquid phase inlet 2 of the fixed-bed reactor I;

[0154] The fixed-bed reactor I includes: a reactor body 1, a liquid inlet 2, N gas inlets 3 (N is a natural number and N≥2), a gas outlet 4, a liquid outlet 5, and (N-1) circulating liquid inlets 12 arranged on the reactor body 1; and N catalyst bed layers 6 and a gas-liquid separation component arranged sequentially from bottom to top inside the reactor body 1; a gas distributor 7 and a liquid distributor 13 are arranged sequentially below each catalyst bed layer 6, and the gas distributor 7 is connected to the gas inlet 3; the gas-liquid separation component includes a separation component cylinder 8, a baffle 9, an overflow pipe 10, and an anti-impact baffle 11 arranged inside the separation component cylinder 8, so that the gas-liquid separation component is divided into a two-phase zone, a liquid zone, and a gas zone; the liquid zone is provided with a liquid outlet 5; and the gas zone is provided with a gas outlet 4;

[0155] Among them, the included angle α between the baffle 9 and the separation component cylinder 8 is 45-90°; the included angle β between the baffle 9 and the overflow pipe 10 is 90-145°; the anti-impact baffle 11 is arranged above the overflow pipe 10, and the included angle γ is 110-145°.

[0156] Among them, the gas phase outlet 4 is connected to N gas phase inlets 3, and a compressor II is installed on the pipeline connecting the gas phase outlet 4 and the gas phase inlets 3; a gas flow controller IV and a gas flow regulating valve X are installed on the pipeline of each gas phase inlet 3.

[0157] Among them, from bottom to top, the second to the Nth section, each section of catalyst bed 6 is independently provided with a circulating liquid inlet 12 below it; the (N-1)th circulating liquid inlet 12 is located below the Nth gas inlet 3; a liquid flow controller V, a liquid flow regulating valve XI and a circulating liquid cooler III are sequentially provided on the pipe connecting the circulating liquid inlet 12 and the liquid outlet 5.

[0158] The reactor cylinder 1 is equipped with a pressure controller VI at the top, and a pressure regulating valve XII is installed on the pipe connecting the gas phase outlet 4, the gas phase inlet 3 and the pressure controller VI.

[0159] The liquid phase zone is equipped with a liquid level controller VII, and the pipe connected to the liquid phase outlet 5 is equipped with a liquid level regulating valve XIII;

[0160] The method includes the following steps:

[0161] (1) The working liquid 02 and the hydrogen-containing gas 01 are subjected to a hydrogenation reaction, and the reaction products are separated into gas and liquid to obtain hydrogenated liquid 03 and hydrogen-containing tail gas 04; wherein, hydrogenated liquid 03 includes: part of hydrogenated liquid 06 and the remaining part of hydrogenated liquid.

[0162] (2) The remaining hydrogenated liquid after the second cooling is subjected to an oxidation reaction to obtain an oxidized liquid 08 rich in hydrogen peroxide;

[0163] (3) Extract the oxidizing liquid 08 rich in hydrogen peroxide to obtain hydrogen peroxide solution 09 and raffinate 010;

[0164] Among them, the hydrogen-containing tail gas 04 is pressurized to obtain pressurized hydrogen-containing tail gas 05, which is returned as a circulating gas and mixed with hydrogen-containing gas 01.

[0165] In this process, a portion of the hydrogenated liquid 06 is subjected to a first cooling, and the resulting cooled hydrogenated liquid 07 is returned as a circulating hydrogenated liquid and mixed into the fixed-bed reactor I.

[0166] In this process, the raffinate 010 is subjected to a third cooling, and the resulting cooled raffinate is returned as a circulating working fluid and mixed into the working fluid 02.

[0167] According to a particularly preferred embodiment of the present invention, a fixed-bed reactor for the hydrogenation reaction of anthraquinone process to prepare hydrogen peroxide is provided. The fixed-bed reactor comprises: a reactor body, a liquid phase inlet, N gas phase inlets, a liquid phase outlet, (N-1) circulating liquid phase inlets and a gas phase outlet disposed on the reactor body, and N catalyst bed layers and a gas-liquid separation component disposed sequentially from bottom to top within the reactor body; wherein, N is a natural number and N≥2;

[0168] A gas distributor is provided below each section of the catalyst bed, and the gas distributor is connected to the gas inlet.

[0169] The gas-liquid separation component includes a separation component cylinder, and a baffle, an overflow pipe, and an anti-impact baffle disposed within the separation component cylinder. The area formed by the overflow pipe and the anti-impact baffle is a two-phase region; the area formed by the baffle and the inner wall of the separator cylinder is a liquid phase region; the area formed by the anti-impact baffle and the inner wall of the separator cylinder is a gas phase region; and the liquid phase region is provided with a liquid phase outlet.

[0170] The liquid phase inlet is located at the bottom of the reactor shell; the gas phase outlet is located at the top of the reactor shell; and the gas phase outlet is connected to N gas phase inlets.

[0171] Among them, (N-1) of the circulating liquid phase inlets are connected to the liquid phase outlets;

[0172] Among them, from bottom to top, the second segment to the Nth segment, each segment of the catalyst bed has an independently provided circulating liquid phase inlet below it, and the (N-1)th circulating liquid phase inlet is located below the Nth gas phase inlet.

[0173] The present invention will be described in detail below through embodiments.

[0174] The hydrogenation catalyst is a supported catalyst with an average particle size of 3-5 mm. The support for the hydrogenation catalyst is alumina, and the active metal is palladium or platinum. The content of the active metal is 0.3 wt% based on the total weight of the hydrogenation catalyst.

[0175] The working solution is an alkyl anthraquinone compound (2-alkyl-9,10-anthraquinone) dissolved in an organic solvent (petroleum fractions with boiling points above 140°C, C7-C4). 11 A solution prepared from saturated alcohols.

[0176] Hydrogen efficiency determination method: Take 5 mL of hydrogenated liquid into a separatory funnel, then add 10 mL of heavy aromatic hydrocarbon and 20 mL of 1+4H2SO4 solution (H2SO4 to water volume ratio is 1:4); bubble and oxidize the above mixed solution until it is bright yellow or orange-yellow (about 10-15 min); wash the extraction reaction solution with pure water 4-5 times, about 20 mL of water each time; titrate the extract with 0.1 mol / L KMnO4 standard solution until it turns slightly red, and the endpoint is when the color does not fade in 30 seconds;

[0177] Hydrogen efficiency (g·H2O2 / L) = standard solution concentration (0.1mol / L) × standard solution volume (mL) × 17.01 / 5.

[0178] Example 1

[0179] Schematic diagram of a fixed-bed reactor for the anthraquinone process to produce hydrogen peroxide ,like Figure 1 As shown, by Figure 1 As can be seen, the fixed-bed reactor I includes: a reactor body 1, a liquid inlet 2, three gas inlets 3, a gas outlet 4, a liquid outlet 5, and two circulating liquid inlets 12. Within the reactor body 1, three catalyst bed sections 6 and a gas-liquid separation component are arranged sequentially from bottom to top. Below each catalyst bed section 6, a gas distributor 7 and a liquid distributor 13 are arranged sequentially, with the gas distributor 7 connected to the gas inlet 3. The gas-liquid separation component includes a separation component body 8, a baffle 9, an overflow pipe 10, and an anti-surge baffle 11 arranged within the separation component body 8, dividing the gas-liquid separation component into a two-phase zone, a liquid zone, and a gas zone. The liquid zone has a liquid outlet 5, and the gas zone has a gas outlet 4.

[0180] The reactor cylinder 1 has an inner diameter of 550 mm and a height of 6000 mm; each catalyst bed 6 has a height of 820 mm; and the gas-liquid separation component has a height of 800 mm.

[0181] Among them, the shortest distance d1 between the gas phase inlet 3 and the lower surface of the catalyst bed 6 is 0.2m; the gas distributor 7 is selected from microporous elements with a pore size of 10-100μm;

[0182] The ratio of the inner diameters of the separation component cylinder 8 and the reactor cylinder 1 is 1:1; the ratio of the heights of the overflow pipe 10 and the separation component cylinder 8 is 0.5:1; the cross-section of the overflow pipe 10 is circular, and the ratio of the inner diameters of the overflow pipe 10 and the separation component cylinder 1 is 0.5:1; the anti-collision baffle 11 is located above the overflow pipe 10, and the shortest distance between the anti-collision baffle 11 and the overflow pipe 10 is 0.3m; the included angle γ of the anti-collision baffle 11 is 120°.

[0183] Among them, the gas phase outlet 4 is connected to 3 gas phase inlets 3, and a compressor II is installed on the pipeline connecting the gas phase outlet 4 and the gas phase inlets 3; a gas flow controller IV and a gas flow regulating valve X are installed on the pipeline of each gas phase inlet 3.

[0184] In this configuration, from bottom to top, the catalyst bed 6 of the second and third sections is independently equipped with a circulating liquid inlet 12 below each; the first circulating liquid inlet 12 is located below the second gas inlet 3, and the second circulating liquid inlet 12 is located below the third gas inlet 3; a liquid flow controller V, a liquid flow regulating valve XI, and a circulating liquid cooler III are sequentially installed on the pipe connecting the circulating liquid inlet 12 and the liquid outlet 5; a liquid flow controller V and a liquid flow regulating valve XI are installed on the pipe connecting the liquid inlet 2.

[0185] A pressure controller VI is installed on the pipe connecting the gas phase outlet 4 and the top of the reactor body 1; a pressure regulating valve XII is installed on the pipe connecting the gas phase outlet 4, the gas phase inlet 3 and the pressure controller VI; a liquid level controller VII is installed in the liquid phase zone, and a liquid level regulating valve XIII is installed on the pipe connecting the liquid phase outlet 5.

[0186] Schematic diagram of an apparatus for producing hydrogen peroxide via the anthraquinone process. ,like Figure 2 As shown, by Figure 2 It is known that the device includes: the fixed bed reactor I, the oxidation reactor VIII and the extraction tower IX connected in sequence; the raffinate outlet of the extraction tower IX is connected to the liquid phase inlet 2 of the fixed bed reactor I;

[0187] Method for preparing hydrogen peroxide via the anthraquinone process The method includes the following steps:

[0188] (1) Add working fluid O2 (4.8m) 3 / h, temperature 40℃) and hydrogen-containing gas O1 (pure hydrogen, 30Nm 3 The hydrogenation reaction is carried out on the gas, and the reaction products are separated into gas and liquid to obtain hydrogenated liquid O3 (at a temperature of 50°C) and hydrogen-containing tail gas O4.

[0189] The hydrogenation process includes: 1) Hydrogen-containing gas bubbles passing through the first gas inlet and the first gas distributor, after making a first contact with the working liquid, enter the first catalyst bed to carry out a first hydrogenation reaction, obtaining a first reaction product; 2) The hydrogen-containing gas bubbles passing through the second gas inlet and the second gas distributor, after making a second contact with the first reaction product and the first stream of circulating hydrogenation liquid, enter the second catalyst bed to carry out a second hydrogenation reaction, obtaining a second reaction product;

[0190] 3) The hydrogen-containing gas bubbles passing through the third gas phase inlet and the third gas distributor come into third contact with the second reaction product and the second stream of circulating hydrogenation liquid, and then enter the third catalyst bed to carry out the third hydrogenation reaction to obtain the reaction product;

[0191] The flow rate ratio of the hydrogen-containing gas at the three gas phase inlets is 0.5:0.3:0.2; the conditions for the first hydrogenation reaction, the second hydrogenation reaction, and the third hydrogenation reaction are each independent, including a pressure of 0.25 MPa and a temperature of 45 °C.

[0192] The catalyst used in each catalyst bed is 100 kg.

[0193] Specifically, the hydrogen-containing tail gas 04 is pressurized to obtain pressurized hydrogen-containing tail gas 05, which is then returned as a circulating gas and mixed with hydrogen-containing gas 01; a portion of the hydrogenated liquid 06 is subjected to a first cooling process, and the resulting cooled hydrogenated liquid 07 (at a temperature of 40°C) is returned as a circulating hydrogenated liquid for hydrogenation reaction. The weight ratio of the portion of hydrogenated liquid 06 to hydrogenated liquid 03 is 50:100; the flow rate ratio of the first circulating hydrogenated liquid to the second circulating hydrogenated liquid is 0.6:0.4.

[0194] (2) The remaining hydrogenated liquid after the second cooling (temperature 50℃) and 177Nm 3 / h air is used for oxidation reaction (temperature is 50℃, pressure is 0.3MPa) to obtain oxidizing liquid 08 rich in hydrogen peroxide;

[0195] (3) Extract the oxidizing liquid 08 rich in hydrogen peroxide and water to obtain hydrogen peroxide solution 09 and raffinate 010; wherein, the raffinate 010 is subjected to a third cooling, and the resulting cooled raffinate (temperature of 40°C) is returned as a circulating working liquid and mixed into working liquid 02.

[0196] The hydrogen peroxide solution contained 27.5 wt% hydrogen peroxide; the hydrogen efficiency of the hydrogenation liquid was 9.3-9.4 g / L, and the hydrogenation selectivity was 98%-99%; the device operated for 2100 hours, the reactor catalyst activity and selectivity remained stable, no signs of deactivation were observed, and the effective anthraquinone content in the working solution decreased by 5%.

[0197] Example 2

[0198] The fixed-bed reactor according to Example 1 is different in that the fixed-bed reactor I is not equipped with two circulating liquid inlets 12, liquid flow controller V, liquid flow regulating valve XI and circulating liquid cooler III;

[0199] The apparatus according to Example 1 differs in that it contains the fixed-bed reactor described above;

[0200] The method of Example 1 is different except that part of the hydrogenated liquid is not used as the circulating hydrogenated liquid. That is, in step (1), the temperature of hydrogenated liquid 03 is 60°C, and the other conditions are the same to obtain hydrogen peroxide solution.

[0201] The hydrogen peroxide content in the hydrogen peroxide solution was 27.5 wt%; the hydrogen efficiency of the hydrogenation liquid was 8.9-9.1 g / L, and the hydrogenation selectivity was 94-96%; after 2100 h of operation, the activity and selectivity of the reactor catalyst decreased, but no obvious signs of deactivation were observed, and the effective anthraquinone content in the working solution decreased by 10%.

[0202] Example 3

[0203] The fixed-bed reactor according to Example 1;

[0204] The apparatus according to Example 1;

[0205] Following the method of Example 1, except that the weight ratio of part of the hydrogenated liquid to the hydrogenated liquid is 10:100, and the other conditions are the same, a hydrogen peroxide solution is obtained.

[0206] The hydrogen peroxide content in the hydrogen peroxide solution was 27.5 wt%; the hydrogen efficiency of the hydrogenation liquid was 9.0-9.15 g / L, and the hydrogenation selectivity was 95-97%; after 2100 hours of operation, the activity and selectivity of the reactor catalyst decreased, but no obvious signs of deactivation were observed, and the effective anthraquinone content in the working solution decreased by 8%.

[0207] Comparative Example 1

[0208] A fixed-bed reactor (550 mm in diameter, 4000 mm in height) contains a catalyst bed (2500 mm high, filled with hydrogenation catalyst). The catalyst bed is not segmented; that is, there is only one catalyst bed segment, 30 Nm. 3 / h pure hydrogen and 4.8m 3 The working fluid enters from the bottom gas phase inlet and liquid phase inlet and is distributed by the distributor.

[0209] The apparatus according to Example 1 differs in that it contains the fixed-bed reactor described above;

[0210] The method of Example 1 is different except that part of the hydrogenated liquid is not used as the circulating hydrogenated liquid. That is, in step (1), the temperature of hydrogenated liquid 03 is 60°C, and the other conditions are the same to obtain hydrogen peroxide solution.

[0211] The hydrogen peroxide content in the hydrogen peroxide solution was 27.5 wt%; the hydrogen efficiency of the hydrogenation liquid was 8.4-8.9 g / L, and the hydrogenation selectivity was 89-94%; after 1800 h of operation, the activity and selectivity of the reactor catalyst decreased significantly, showing signs of deactivation, and the effective anthraquinone content in the working solution decreased by 15%.

[0212] Comparative Example 2

[0213] The fixed-bed reactor of Comparative Example 1 is different in that it has a capacity of 30 Nm³. 3 / h pure hydrogen and 4.8m 3 The working fluid is fed into the reactor from the top inlet at a temperature of 40°C. The pressure at the top of the reactor is 0.3 MPa, and the temperature at the bottom of the reactor is 60°C. The reaction products flow out from the bottom of the reactor into a gas-liquid separator. The hydrogen-containing tail gas is discharged from the system, and the hydrogenated liquid is transported to the oxidation reactor.

[0214] Inside the oxidation reactor, with 177 Nm 3 / h air reacts to obtain an oxidizing liquid containing hydrogen peroxide; in the extraction tower, the oxidizing liquid and water are extracted to obtain a hydrogen peroxide solution; the raffinate is returned as a circulating working liquid and mixed into the working liquid.

[0215] The hydrogen peroxide content in the hydrogen peroxide solution was 27.5 wt%; the hydrogen efficiency of the hydrogenation liquid was 7.6-8.7 g / L, and the hydrogenation selectivity was 80-92%; after 800 hours of operation, the activity and selectivity of the reactor catalyst decreased significantly, the deactivation phenomenon was obvious, and the effective anthraquinone content in the working solution decreased by 18%.

[0216] By comparing Examples 1-2 and Comparative Examples 1-2, it can be seen that the method provided by the present invention for preparing hydrogen peroxide, especially by adjusting the settings of the fixed-bed reactor, can significantly improve the hydrogen efficiency of fixed-bed alkyl anthraquinone hydrogenation, and the hydrogenation selectivity can be increased to 98%. This effectively improves the selectivity of the hydrogenation reaction, the efficiency of the equipment, and extends the service life of the catalyst, resulting in good economic and social benefits.

[0217] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A hydrogenation method for preparing hydrogen peroxide using the anthraquinone process, characterized in that, The hydrogenation process is carried out in a fixed-bed reactor; The fixed-bed reactor includes: a reactor cylinder, a liquid phase inlet, N gas phase inlets, a liquid phase outlet and a gas phase outlet arranged sequentially from bottom to top on the reactor cylinder, and N catalyst bed layers and a gas-liquid separation component arranged sequentially from bottom to top in the reactor cylinder; wherein, N is a natural number and N≥2; the height-to-diameter ratio of the catalyst bed layer is 1:0.5-5; Each catalyst bed is provided with a gas distributor below it, and the gas distributor is connected to the gas inlet; the shortest distance d1 between the gas inlet and the lower surface of the catalyst bed is 0.1-1.5m; the gas distributor is selected from perforated tubes or microporous elements; The gas-liquid separation component is divided into a two-phase region, a liquid phase region, and a gas phase region; the liquid phase region is provided with a liquid phase outlet; and the gas phase region is provided with a gas phase outlet. The fixed-bed reactor further includes: (N-1) circulating liquid phase inlets connected to the liquid phase outlet, and each circulating liquid phase inlet is independently arranged on the reactor shell; from bottom to top, in the 2nd to the Nth section, each section of the catalyst bed has its own independently arranged circulating liquid phase inlet below it; the shortest distance d2 between the circulating liquid phase inlet and the bottom of the catalyst bed is 0.2-1.2m; The method includes: hydrogen-containing gas entering the reactor cylinder through N gas phase inlets, then being dispersed into hydrogen-containing gas bubbles by N gas distributors, and then contacting the working liquid entering the reactor cylinder through the liquid phase inlet, and undergoing hydrogenation reactions independently in N catalyst bed sections. The resulting reaction products flow upward into the gas-liquid separation unit for gas-liquid separation, and the resulting hydrogenated liquid flows out through the liquid phase outlet, while the resulting hydrogen-containing tail gas is discharged through the gas phase outlet; a portion of the hydrogenated liquid is returned to the reactor cylinder as circulating hydrogenated liquid through (N-1) circulating liquid phase inlets; the weight ratio of the circulating hydrogenated liquid to the hydrogenated liquid is 15-60:

100.

2. The hydrogenation method according to claim 1, wherein, The catalyst bed has 2-8 segments.

3. The hydrogenation method according to claim 2, wherein, The catalyst bed has 3-5 segments.

4. The hydrogenation method according to claim 2, wherein, The height-to-diameter ratio of the catalyst bed is 1:0.8-3.

5. The hydrogenation method according to claim 2, wherein, The shortest distance d1 between the gas phase inlet and the lower surface of the catalyst bed is 0.2-0.8m.

6. The hydrogenation method according to claim 1 or 2, wherein, The aperture of the perforated tube is 0.5-12 mm; the aperture of the microporous element is 0.2-500 μm.

7. The hydrogenation method according to claim 6, wherein, The diameter of the perforated tube is 1-8 mm.

8. The hydrogenation method according to claim 6, wherein, The pore size of the microporous element is 0.5-200μm.

9. The hydrogenation method according to claim 6, wherein, A liquid distributor is provided below each section of the catalyst bed, and the liquid distributor is located below the gas distributor.

10. The hydrogenation method according to any one of claims 1-3, wherein, The gas-liquid separation component includes a separation component cylinder, and a baffle, an overflow pipe, and an anti-impact baffle disposed within the separation component cylinder.

11. The hydrogenation method according to claim 10, wherein, The area formed by the overflow pipe and the anti-impact baffle is the two-phase region; the area formed by the baffle and the inner wall of the separator cylinder is the liquid phase region; and the area formed by the anti-impact baffle and the inner wall of the separator cylinder is the gas phase region.

12. The hydrogenation method according to claim 10, wherein, The ratio of the inner diameter of the separation component cylinder to the inner diameter of the reactor cylinder is 0.2-1.5:

1.

13. The hydrogenation method according to claim 12, wherein, The ratio of the inner diameter of the separation component cylinder to the inner diameter of the reactor cylinder is 0.5-1:

1.

14. The hydrogenation method according to claim 10, wherein, The included angle α between the baffle and the separation component cylinder is 45°-90°, and the included angle β between the baffle and the overflow pipe is 90°-145°.

15. The hydrogenation method according to claim 10, wherein, The ratio of the inner diameter of the overflow pipe to that of the separation component cylinder is 0.15-0.75:

1.

16. The hydrogenation method according to claim 15, wherein, The ratio of the inner diameter of the overflow pipe to the inner diameter of the separation component cylinder is 0.2-0.6:

1.

17. The hydrogenation method according to claim 10, wherein, The height ratio of the overflow pipe to the separation component cylinder is 0.2-0.95:

1.

18. The hydrogenation method according to claim 17, wherein, The height ratio of the overflow pipe to the separation component cylinder is 0.5-0.8:

1.

19. The hydrogenation method according to claim 10, wherein, The anti-rush baffle is positioned above the overflow pipe.

20. The hydrogenation method according to claim 19, wherein, The shortest distance between the lower edge of the anti-collision baffle and the upper end of the overflow pipe is 0.3-1.2m.

21. The hydrogenation method according to claim 20, wherein, The shortest distance between the lower edge of the anti-collision baffle and the upper end of the overflow pipe is 0.3-0.8m.

22. The hydrogenation method according to claim 10, wherein, The anti-impact baffle has a conical structure.

23. The hydrogenation method according to claim 22, wherein, The included angle γ of the conical structure is 110°-145°.

24. The hydrogenation method according to any one of claims 1-4, wherein, The liquid phase inlet is located at the bottom of the reactor shell; the gas phase outlet is located at the top of the reactor shell.

25. The hydrogenation method according to claim 24, wherein, The gas phase outlet is connected to N gas phase inlets.

26. The hydrogenation method according to claim 25, wherein, A compressor is installed on the pipeline connecting the gas phase outlet and the gas phase inlet.

27. The hydrogenation method according to claim 24, wherein, A gas flow controller is installed on the pipe of each gas inlet.

28. The hydrogenation method according to claim 27, wherein, A gas flow regulating valve is installed on the pipeline connecting the gas phase inlet and the gas flow controller, and the gas flow regulating valve is located between the gas phase inlet and the gas flow controller.

29. The hydrogenation method according to claim 1, wherein, From bottom to top, the (N-1)th circulating liquid phase inlet is located below the Nth gas phase inlet.

30. The hydrogenation method according to claim 1, wherein, The shortest distance d2 between the circulating liquid phase inlet and the bottom of the catalyst bed is 0.3-0.8m.

31. The hydrogenation method according to claim 1, wherein, A circulating liquid cooler is installed on the pipe connecting the circulating liquid inlet and the liquid outlet.

32. The hydrogenation method according to claim 1, wherein, A liquid flow controller is also installed on the pipe connecting the circulating liquid inlet and the liquid outlet, and the liquid flow controller is located before the circulating liquid cooler.

33. The hydrogenation method according to claim 1, wherein, A liquid flow regulating valve is also installed on the pipe connecting the circulating liquid phase inlet and the liquid phase outlet, and the liquid flow regulating valve is located between the liquid flow controller and the circulating cooler.

34. The hydrogenation method according to any one of claims 1-5, wherein, A pressure controller is installed at the top of the reactor cylinder.

35. The hydrogenation method according to claim 27, wherein, A pressure regulating valve is installed on the pipeline connecting the gas phase outlet and the gas phase inlet.

36. The hydrogenation method according to claim 35, wherein, The liquid phase region of the gas-liquid separation component is equipped with a liquid level controller.

37. The hydrogenation method according to claim 36, wherein, A liquid level regulating valve is installed on the pipe connected to the liquid phase outlet.

38. The hydrogenation method according to claim 1, wherein, The hydrogenation reaction process includes: 1) The hydrogen-containing gas bubbles that pass through the first gas phase inlet and the first gas distributor come into first contact with the working fluid and then enter the first catalyst bed to carry out the first hydrogenation reaction to obtain the first reaction product; 2) The hydrogen-containing gas bubbles passing through the second gas inlet and the second gas distributor come into a second contact with the first reaction product and then enter the second catalyst bed to carry out a second hydrogenation reaction to obtain the second reaction product; 3) The hydrogen-containing gas bubbles passing through the Nth gas phase inlet and the Nth gas distributor come into contact with the (N-1)th reaction product for the Nth time, and then enter the Nth catalyst bed to carry out the Nth hydrogenation reaction to obtain the reaction product.

39. The hydrogenation method according to claim 38, wherein, The conditions for the first hydrogenation reaction, the second hydrogenation reaction, ... and the Nth hydrogenation reaction each independently include: a pressure of 0.03-0.35 MPa; and a temperature of 40-80 °C.

40. The hydrogenation method according to claim 39, wherein, The conditions for the first hydrogenation reaction, the second hydrogenation reaction, ... and the Nth hydrogenation reaction each independently include: a pressure of 0.05-0.25 MPa; and a temperature of 45-65 °C.

41. The hydrogenation method according to claim 38, wherein, With m 3 The ratio of the working fluid to the hydrogenation catalyst (in tons) is 1-50:1; wherein the catalyst bed is filled with the hydrogenation catalyst.

42. The hydrogenation method according to claim 41, wherein, With m 3 The ratio of the working fluid to the hydrogenation catalyst (in tons) is 5-30:

1.

43. The hydrogenation method according to claim 1, wherein, The hydrogenation method further includes: returning the hydrogen-containing tail gas as a recycle gas and mixing it with the hydrogen-containing gas.

44. The hydrogenation method according to claim 43, wherein, The hydrogen-containing exhaust gas is pressurized, and the resulting pressurized hydrogen-containing exhaust gas is used as the circulating gas.

45. The method according to claim 1, wherein, A portion of the hydrogenated liquid is subjected to a first cooling process, and the resulting cooled hydrogenated liquid is used as the circulating hydrogenated liquid.

46. ​​The method according to claim 45, wherein, The temperature of the cooling hydrogenated liquid is 15-70℃.

47. The method according to claim 46, wherein, The temperature of the cooling hydrogenated liquid is 20-50℃.

48. The method according to claim 47, wherein, The temperature of the cooling hydrogenated liquid is 35-45℃.

49. The method according to claim 1, wherein, The weight ratio of the circulating hydrogenated liquid to the hydrogenated liquid is 15-50:

100.

50. An apparatus for preparing hydrogen peroxide via the anthraquinone process, characterized in that, The apparatus comprises: a fixed-bed reactor, an oxidation reactor, and an extraction tower selected from any one of claims 1-49, connected in sequence; The fixed-bed reactor is used to perform a hydrogenation reaction between the working fluid and the hydrogen-containing gas, and the reaction products are separated into a hydrogenated liquid and a hydrogen-containing tail gas. The oxidation reactor is connected to the liquid phase outlet of the fixed-bed reactor and is used to oxidize the hydrogenated liquid to obtain an oxidized liquid rich in hydrogen peroxide. The extraction tower is connected to the outlet of the oxidation reactor and is used to extract the hydrogen peroxide-rich oxidizing liquid to obtain a hydrogen peroxide solution and raffinate.

51. The apparatus according to claim 50, wherein, The raffinate outlet of the extraction tower is connected to the liquid phase inlet of the fixed-bed reactor, which is used to return the raffinate as a circulating working fluid and mix it into the working fluid.

52. A method for preparing hydrogen peroxide using the anthraquinone process, characterized in that, The method is performed in the apparatus of claim 50 or 51; wherein the method includes the following steps: (1) The working fluid and hydrogen-containing gas are subjected to hydrogenation reaction, and the reaction products are separated into gas and liquid to obtain hydrogenated liquid and hydrogen-containing tail gas; (2) The hydrogenated liquid is subjected to an oxidation reaction to obtain an oxidizing liquid rich in hydrogen peroxide; (3) Extract the hydrogen peroxide-rich oxidizing liquid to obtain a hydrogen peroxide solution and a raffinate.

53. The method according to claim 52, wherein, The method further includes: returning the hydrogen-containing exhaust gas as a recirculating gas and mixing it with the hydrogen-containing gas.

54. The method according to claim 53, wherein, The method further includes: returning a portion of the hydrogenated liquid as a circulating hydrogenated liquid and carrying out the hydrogenation reaction.

55. The method according to claim 54, wherein, A portion of the hydrogenated liquid is subjected to a first cooling process, and the resulting cooled hydrogenated liquid is used as the circulating hydrogenated liquid.

56. The method according to claim 55, wherein, Before the oxidation reaction is carried out, the hydrogenated liquid is subjected to a second cooling.

57. The method according to claim 56, wherein, The method further includes: returning the raffinate as a circulating working fluid and mixing it into the working fluid.

58. The method according to claim 57, wherein, The raffinate is subjected to a third cooling process, and the resulting cooled raffinate is used as the circulating working fluid.

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