CN106430108B - System and method for preparing hydrogen peroxide by anthraquinone method under supergravity condition - Google Patents

Abstract

The invention provides a system and a method for preparing hydrogen peroxide by an anthraquinone process under the condition of supergravity, wherein the system comprises a supergravity rotating packed bed, a gas conveying device, a liquid conveying device, a first preheating device and a second preheating device; the high-gravity rotating packed bed comprises a shell, a reactor and a rotating device, wherein the reactor is positioned in the shell, a catalyst is filled in the wall of the reactor, a through hole is formed in the wall of the reactor, and the reactor is communicated with the shell through the through hole; the rotating device is connected with the reactor and is used for driving the reactor to rotate. The system and the method for preparing the hydrogen peroxide by the anthraquinone method have the advantages of short reaction time, high hydrogenation efficiency, high mass transfer efficiency, simple operation, small equipment volume, small investment and the like when being used for preparing the hydrogen peroxide.

Description

System and method for preparing hydrogen peroxide by anthraquinone method under supergravity condition

Technical Field

The invention belongs to the technical field of hydrogen peroxide preparation, relates to a system and a method for preparing hydrogen peroxide by an anthraquinone method under a hypergravity condition, and particularly relates to a system and a method for preparing hydrogen peroxide by hydrogenation of anthraquinone derivatives under a hypergravity condition.

Background

Hydrogen peroxide is an important chemical raw material and a fine chemical product, and only generates water and active oxygen in the process of participating in chemical reaction, so the hydrogen peroxide has the characteristic of no secondary pollution, is called as a green chemical, and is widely applied to papermaking, spinning, chemical synthesis, electronics, food processing, medicines and environmental protection. Protection and the like. Is one of the fastest growing chemicals used in recent 10 years. The current global production of hydrogen peroxide is growing at a rate of 6% per year, with a total annual plant capacity of about 2800kt (100%), with major focus on large foreign companies. In recent years, the domestic hydrogen peroxide production is developed very rapidly, the market demand is also increased continuously, and in 2009, the capacity and the yield of China jump the first world and are nearly twice of those of the United states. With the increasing national requirements for environmental protection, the application range and the demand of hydrogen peroxide are also expanding day by day, and chemicals which cause serious pollution to the environment are gradually replaced in some fields.

At present, the world production methods of hydrogen peroxide include an isopropanol method, an electrolysis method, a hydrogen-oxygen direct synthesis method, a cathode anode reduction method, a vacuum enrichment method, an anthraquinone method and the like, and along with the influence of production cost and environmental protection, a plurality of methods are gradually eliminated, while the anthraquinone method is the most main method for producing hydrogen peroxide at home and abroad due to mild conditions, high safety and mature process. The anthraquinone process adopts anthraquinone as a working carrier and obtains hydrogen peroxide through the procedures of hydrogenation, oxidation, extraction and the like. The hydrogenation process is the core of the whole process, and the hydrogenation process currently mainly uses a palladium catalyst and a fixed bed process.

Although the technology of the anthraquinone method is nearly mature after being improved, the method has some defects all the time, most fixed bed palladium catalysts are prepared by adopting spherical or strip-shaped carriers to carry active component palladium, but the catalysts are all solid structures, the increase of the surface area is limited, the catalytic activity and the selectivity are difficult to further improve, in the practical industrial application, the solid catalyst has high bulk density, the load of a catalyst bed layer is large after the solid catalyst is filled, and the resistance of the catalyst bed layer is increased in the reaction; on the other hand, the existing fixed bed reactor technology adopts a vertical reactor, hydrogen and working fluid are fed from the top of the fixed bed reactor, the gas phase in the reactor is a continuous phase, the liquid phase is sprayed from the top and descends in a trickle shape in the fixed bed under the action of gravity, the reactor is called a trickle bed, the gas phase hydrogen needs to participate in the reaction and can reach the surface of the catalyst through liquid phase mass transfer, the mass transfer resistance of the gas phase hydrogen is large, the hydrogenation reaction is not facilitated, meanwhile, the local utilization efficiency of the reactor is low due to the phenomenon of uneven distribution of the liquid phase in the axial direction and the radial direction, the local hydrogenation of the catalyst bed layer causes agglomeration, and the bias flow is further intensified, so that the bed resistance rapidly rises and the production operation cannot be carried. Therefore, the improvement of the reactor is strengthened, and the mass transfer between gas and liquid is enhanced, so that the reaction is facilitated.

The technical workers at home and abroad do a great deal of work in the aspects of exploration of hydrogenation processes and design of reactors, and the reasonable design can effectively improve the gas-liquid contact area, control the contact time, play a role in strengthening the gas-liquid contact mixing effect and further improve the production capacity of equipment. Such as:

CN101229915A discloses a method for producing hydrogen peroxide by anthraquinone method and GB 2334028A and JP-Kokai143216 disclose improved methods for hydrogenation trickle bed, the improved working solution and hydrogen flow downwards from the top of the bed or upwards from the bottom of the bed in cocurrent, by adjusting the liquid-gas ratio and the hydrogen pressure, the working solution and hydrogen self-form foam mixture without any foaming device and flow through the catalyst bed layer in cocurrent, the gas-liquid mass transfer is strengthened, but the reaction equipment has larger volume and the defect that the catalyst is easy to break at high flow rate.

The high-gravity rotating packed bed reactor is a new type heat and mass transfer equipment, and has the advantages of small volume and high mass transfer coefficient. The supergravity refers to the force to which a substance is subjected in an environment much larger than the acceleration of gravity of the earth, and the supergravity technology achieves the purpose of simulating a supergravity environment through the action of a centrifugal force field. The core of the technology lies in the great enhancement of the transfer process and the micro-mixing process, so that the technology has great significance for the multiphase process needing the enhancement of the inter-phase transfer process and the mixing and reaction process needing the enhancement of the micro-mixing in the phase or the quasi-homogeneous phase. The supergravity rotating packed bed can greatly strengthen the gas-liquid mass transfer contact effect, and is important to be related to packing except for forming a supergravity field under the condition of high-speed rotation.

CN 102764627a discloses a supergravity rotating packed bed reaction equipment. Consists of a shell, a rotating bed reaction chamber in the shell and a direct transmission mechanism. The wall of the rotating bed is provided with holes, a liquid inlet pipe and an air inlet pipe which are fixed at the top of the shell are arranged in the rotating bed, the direct transmission mechanism is fixedly arranged at the bottom of the rotating bed, the wall of the rotating bed is a porous packing layer, the inner wall of the rotating bed is of a net-shaped structure, and the thickness of the packing layer is 5-20 layers; the bottom of the rotating bed is of a non-porous or porous structure.

At present, the supergravity technology is mostly applied to rectification, extraction, absorption and preparation of superfine powder, for example, CN101774895SA discloses a process and a device for preparing guaiacol by continuously hydrolyzing diazonium salt of anthranilate, the reaction is a liquid-liquid reaction, the core device of the invention comprises a hydrolysis reactor consisting of a supergravity rotating packed bed and a coil pipe, and the invention has the advantages that: the production of by-products can be reduced, the yield is improved to more than 90%, the discharge of three wastes is reduced, the production cost is reduced, the equipment volume is small, the start-stop time is short, and the installation, the operation and the maintenance are convenient. CN 101462933A discloses a method and equipment for synthesizing p-hydroxybenzaldehyde by catalytic oxidation, wherein the reaction involves gas-liquid two phases, and after the supergravity technology is used, the conversion rate of p-cresol is high, the product yield and purity are high, the operation is simple, and the equipment volume is small. CN 1539743A discloses a method for preparing nano zinc sulfide by a hypergravity reaction crystallization method, wherein the reaction relates to gas-liquid-solid three phases, zinc nitrate and hydrogen sulfide gas are used as raw materials, and the nano zinc sulfide prepared by the method has lower cost, uniform particle size, narrow particle size distribution and more complete crystal form compared with the prior art. However, all the fillers introduced above are inert structured fillers, and the fillers have no catalytic property.

So far, no patent report of the application of the hypergravity technology combined with the bulk catalyst filler in the field of hydrogen peroxide preparation exists. The raw materials and process conditions for preparing hydrogen peroxide by the anthraquinone method are different from those in the method, the result of applying the supergravity rotating packed bed to the preparation of hydrogen peroxide by the anthraquinone method is unpredictable, and the process conditions also need to be further researched.

Disclosure of Invention

Aiming at the problems of low mass transfer efficiency, large equipment volume, low production capacity, low catalyst efficiency and the like of a method for synthesizing hydrogen peroxide by catalytic oxidation by taking 2-ethylanthraquinone as a raw material in the prior art, the invention aims to provide a system and a method for preparing hydrogen peroxide by an anthraquinone method under a supergravity condition.

In order to achieve the purpose, the invention adopts the following technical scheme:

one of the purposes of the invention is to provide a system for preparing hydrogen peroxide by an anthraquinone process, which comprises a hypergravity rotating packed bed, a gas conveying device, a liquid conveying device, a first preheating device and a second preheating device;

the high-gravity rotating packed bed comprises a shell, a reactor and a rotating device, wherein the reactor is positioned in the shell, a catalyst is filled in the wall of the reactor, a through hole is formed in the wall of the reactor, and the reactor is communicated with the shell through the through hole; the rotating device is connected with the reactor and is used for driving the reactor to rotate;

the gas conveying device is communicated with a gas inlet arranged on the reactor and/or the shell through a gas conveying pipeline, and the gas conveying pipeline is provided with a first preheating device;

the liquid conveying device is communicated with a liquid inlet arranged on the reactor through a liquid conveying pipeline, and a second preheating device is arranged on the liquid conveying pipeline;

the shell is provided with a gas outlet and a liquid outlet.

As known to those skilled in the art, the system further comprises an oxidation device, an extraction device, a purification device and the like, which are common devices in the field and are not described in detail herein. It is also known to those skilled in the art that the supergravity rotating packed bed is entirely sealed when the liquid inlet, the liquid outlet, the gas inlet and the gas outlet are sealed, and the reactor rotor is communicated with the housing only through the through holes provided in the wall to ensure that gas and liquid enter from the inlet end and must pass through the reactor rotor to participate in the reaction before being discharged.

The super-gravity rotating bed is horizontal or vertical, and is preferably horizontal.

Preferably, a mesh structure is arranged in the through hole.

Preferably, the material of the mesh structure is selected from any one or a combination of at least two of metal, silica gel or polymer material, preferably steel bar, and typical but not limiting combinations such as metal and silica gel, metal and polymer material, silica gel and polymer material, and the like. The design of the through holes and the net-shaped structures positioned in the through holes greatly reduces the catalyst resistance of the reactor. In traditional reactor, because the pressure of pump is lower, the horizontal initial velocity of outflow liquid is little in the liquid distribution pipe, leads to can not be along radial incident catalyst bed, and the wet rate of catalyst is lower, and based on this kind of consideration, the wall of reactor sets up the through-hole to set up network structure in the through-hole, compare in the increase of traditional slit design aperture ratio, be convenient for the circulation of working solution.

Preferably, there are a plurality of through holes, and the interval between adjacent through holes is 1mm to 100cm, such as 2mm, 3mm, 5mm, 8mm, 10mm, 30mm, 50mm, 100mm, 500mm, 1cm, 3cm, 5cm, 8cm, 15cm, 30cm, 50cm, 80cm or 90 cm.

Preferably, the through-hole is circular.

Preferably, the reactor is a hollow cylinder, and a through hole is arranged on the wall of the cylinder.

Preferably, the wall thickness of the cylinder is 5-50mm, such as 8mm, 10mm, 15mm, 18mm, 20mm, 30mm, 40mm or 45mm, etc.

Preferably, the radius of the cylinder is 5-50mm, such as 8mm, 10mm, 15mm, 18mm, 20mm, 30mm, 40mm or 45mm, etc.

Preferably, the housing is shaped as a hollow cylinder, the radius of the housing being 5-500mm, such as 10mm, 20mm, 50mm, 80mm, 100mm, 150mm, 200mm, 300mm, 400mm, 450mm, or the like.

The liquid conveying device comprises a working liquid storage tank and a pump, and the working liquid storage tank is connected with the liquid inlet through the pump.

Preferably, the gas conveying device comprises a hydrogen storage tank and a nitrogen storage tank, and the hydrogen storage tank and the nitrogen storage tank are both connected with the gas inlet through the first preheating device.

Preferably, the system further comprises a condensing device and a product storage tank, wherein an inlet of the condensing device is connected with the liquid outlet; the product storage tank is connected with the liquid outlet of the condensing device and the liquid outlet of the shell.

Preferably, the system also comprises a spraying device which is connected with the liquid conveying device and is used for spraying the working liquid onto the wall of the reactor, so that the contact reaction of the working liquid and the hydrogen is more facilitated.

Preferably, the spray set includes the feed liquor pipe, feed liquor pipe one end opening, the other end is sealed, and the open end of feed liquor pipe links to each other with liquid conveyor, and the blind end of feed liquor pipe stretches into in the reactor, and sets up the through-hole on stretching into the wall of the feed liquor pipe of reactor for on spouting the wall of reactor with the working solution.

The system is provided with two gas inlets and a sealing piston which are matched, wherein one gas inlet is positioned on the shell, and the other gas inlet is positioned on the reactor. The two gas inlets and the sealing piston are arranged to facilitate the forward flow or reverse flow contact of the hydrogen and the working liquid, for example, when the forward flow contact of the hydrogen and the working liquid is required, the gas inlets on the shell are blocked by the sealing piston.

As a preferred technical scheme, the system comprises at least two series-connected hypergravity rotating packed beds, wherein a liquid outlet of the former hypergravity rotating packed bed is connected with a liquid inlet of the latter hypergravity rotating packed bed; the gas conveying device is respectively connected with the gas inlets on the at least two hypergravity rotating packed beds. Preferably the system comprises 1-100 series-connected hypergravity rotating packed beds, the system may comprise 2, 10, 30, 50, 60, 70, 80 or 90 hypergravity rotating packed beds. The number of the rotating packed beds can be determined by the skilled person according to actual needs. The hypergravity rotating packed bed can be used singly or in series, thereby controlling the hydrogen efficiency of 1-20 g.

It is a further object of the present invention to provide a process for the preparation of hydrogen peroxide using the system as described above.

As a preferred technical scheme, the method comprises the following steps:

(1) loading hydrogenation catalyst into the wall of the high-gravity rotating packed bed reactor, and rotating the high-gravity rotating packed bed at 0-3000r/min (such as 10r/min, 50r/min, 100r/min, 300r/min, 500r/min, 800r/min, 1000r/min, 2000r/min, 2300r/min, 2500r/min or 2800 r/min);

(2) introducing both preheated hydrogen and working liquid into the reactor, or respectively introducing the hydrogen and the working liquid into a shell of the supergravity rotating packed bed and the reactor; controlling the pressure in the supergravity rotating packed bed to be 0.1-10MPa, such as 0.15MPa, 0.2MPa, 0.3MPa, 0.5MPa, 1.0MPa, 2MPa, 5MPa, 7MPa, 8MPa or 9MPa, etc., so that the hydrogen and the working solution are in parallel flow, cross flow or countercurrent contact reaction on the surface of the catalyst to obtain a liquid phase reaction product and a gas phase reaction product, and the liquid phase reaction product flows out through the through holes and is subjected to post-treatment to obtain a hydrogen peroxide product.

The invention provides a method for preparing hydrogen peroxide by an anthraquinone process, which mainly replaces a traditional vertical or horizontal reactor with a supergravity reactor. The reaction of anthraquinone hydrogenation to produce hydroanthraquinone is to introduce the working liquid containing anthraquinone and hydrogen into a supergravity rotating packed bed reactor filled with hydrogenation catalyst to produce hydroanthraquinone through the hydrogenation reaction between anthraquinone in the working liquid and hydrogen under the action of the catalyst, and to guide the hydrogenated working liquid containing hydroanthraquinone out of the reactor for further oxidation, extraction and other steps to obtain hydrogen peroxide product.

According to the preparation method of the hydrogen peroxide, the working solution containing the anthraquinone and the hydrogen are respectively introduced into the hypergravity rotating packed bed from the liquid inlet and the gas inlet to carry out countercurrent, cross-flow or cocurrent reaction.

The reaction process of the working solution and the hydrogen gas in counter current comprises the following steps: introducing hydrogen into the outer cavity of the reactor and introducing the hydrogen into the filler filled with the catalyst under the action of gas pressure; after the working solution is introduced into the reactor, the circumferential speed is increased under the action of centrifugal force, and the working solution is gradually distributed on the inner wall of the reactor. In the whole process, the anthraquinone-containing working solution is dispersed and crushed by the catalyst filler to form extremely large and constantly updated microelements, and the zigzag flow channel further aggravates the updating of the interface. The anthraquinone-containing working solution reversely contacts with hydrogen at a very high relative speed under the conditions of high dispersion, high turbulence, strong mixing and rapid interface updating, and the mass transfer process is greatly enhanced. And then, the working solution containing anthraquinone and hydroanthraquinone is thrown to the shell by the reactor, collected and leaves the hypergravity rotating packed bed through the liquid outlet, and the hydrogen leaves the hypergravity rotating packed bed through the gas outlet, so that the whole reaction process is completed.

The reaction process of the working solution and hydrogen cocurrent flow is as follows: the hydrogen and the working solution are both introduced into the inner cavity of the reactor, the circumferential speed of the gas and the liquid is increased in the rotating process, the working solution is gradually distributed on the inner wall of the reactor, the gas and the liquid are in parallel flow contact in the packing layer in the process, and then the hydrogenated liquid and the hydrogen are separated from each other through the gas-liquid outlet and the condenser pipe liquid distributor.

The method for producing hydrogen peroxide by the anthraquinone process provided by the invention mainly changes the hydrogenation process operation in a hydrogenation reactor which utilizes a gravity field to carry out mass transfer in the prior art, and replaces the traditional vertical reactor with a supergravity rotating packed bed, thereby bringing about the effect that the hydrogenation efficiency is obviously improved compared with the hydrogenation efficiency of the traditional trickle bed. In the method, reactants are controlled to enter the reactor from the liquid inlet, the continuous phase is anthraquinone-containing working solution, hydrogen enters the reactor from the gas inlet, and the reactants and the hydrogen are subjected to dispersion, mixing and contact reaction under the action of centrifugal force. Wherein, when the hydrogen meets the catalyst particles, the surface of the catalyst is exposed instantly and is contacted and adsorbed with the hydrogen because the catalyst is continuously updated; when the anthraquinone-containing working solution meets catalyst particles, as a liquid film on the surface of the catalyst is continuously updated, the surface of the catalyst adsorbing hydrogen is instantly exposed and is contacted with the anthraquinone-containing working solution, the gas phase and the liquid phase on the surface of the catalyst are instantly and alternately updated, and mass transfer and hydrogenation reaction are simultaneously carried out at high speed and high efficiency under the action of strong centrifugal force. The gas-liquid in the reactor is updated quickly, so the phenomenon of caking caused by over hydrogenation hardly occurs.

The filling amount of the catalyst in the step (1) is controlled to be 20-200m L, such as 30m L, 40m L0, 50m L1, 70m L, 80m L, 90m L, 100m L, 120m L, 130m L, 150m L or 180m L.

Preferably, the catalyst in step (1) is a supported palladium catalyst, and the carrier in the supported palladium catalyst is a non-spherical granular carrier with a hollow structure, preferably any one or a combination of at least two of raschig rings, wheel rings, porous strips or porous rings, and further preferably raschig rings. The non-spherical granular carrier with the hollow structure is characterized in that proper spaces (regular or irregular) are formed in the carrier body for reducing the bulk ratio and enlarging the external surface area, and the shapes of Raschig rings, wheel rings, porous strips or porous rings and the like are adopted. The specific size of the catalyst particles selected for use in the present invention may be selected according to the specific process conditions, throughput, etc. of the actual industrial application.

Preferably, the supported palladium catalyst has a palladium loading of 0.01 to 1wt%, such as 0.05 wt%, 0.1 wt%, 0.3 wt%, 0.5 wt%, 0.7 wt%, or 0.9 wt%, and the like. According to specific embodiments, the catalyst in the supergravity device can be a commonly used hydrogenation catalyst with various specifications, and is usually a granular supported palladium catalyst such as a sphere or a strip, and the carrier of the catalyst is usually solid spherical or strip alumina. The more preferable catalyst carrier of the invention is a supported palladium catalyst (the supported amount of palladium is 0.01 wt% to 1 wt%) obtained by impregnating Raschig ring alumina, silica or a mixed carrier of alumina and silica with an active component palladium.

Preferably, the catalyst in step (1) is an alumina composite palladium black catalyst, and the mass percentage content of palladium black in the alumina composite palladium black catalyst is preferably 0.1% to 5%, such as 0.3%, 0.5%, 1%, 2%, 3%, or 4%.

Preferably, the alumina composite palladium black catalyst is in a spherical shape with a diameter of 1-100mm (such as a diameter of 2mm, 3mm, 5mm, 10mm, 20mm, 30mm, 50mm, 70mm or 80mm, etc.), has an aspect ratio of 1:1-1:10 (such as an aspect ratio of 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8 or 1:9, etc.), has a Raschig ring shape with a diameter of 1-100mm (such as a diameter of 2mm, 3mm, 5mm, 10mm, 20mm, 30mm, 50mm, 70mm or 80mm, etc.), or has a clover shape with the same size.

The introduction mode of the working solution and the hydrogen in the step (2) is as follows: the working liquid is sprayed out from the liquid inlet pipe and sprinkled on the inner wall of the rotating reactor, the hydrogen axially or radially flows through the catalyst in the wall of the reactor, and the hydrogen and the catalyst are in concurrent, cross-flow or countercurrent contact on the wall of the reactor.

Preferably, the hydrogen flow rate is 1-100L/min, such as 2L/min, 5L 0/min, 8L 1/min, 10L 2/min, 20L 3/min, 30L 4/min, 50L 5/min, 70L 6/min or 90L 7/min, etc., and the working fluid flow rate is 1-100L 8/min, such as 2L 9/min, 5L/min, 8L/min, 10L/min, 20L/min, 30L/min, 50L/min, 70L/min or 90L/min, etc.

Preferably, the volume ratio of the hydrogen to the working fluid in the supergravity rotating packed bed in the step (2) is 10:1 to 15:1, such as 12:1, 11:1, 13:1, 14:1 or 14.5: 1.

Preferably, the working solution in step (2) is composed of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethylanthraquinone, and the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, such as 76:24, 77:23, 78:22 or 79:21, the concentration of the heavy aromatic hydrocarbon is 660-680 m/, such as 662m 0/1, 665m 2/3, 668m 4/5, 670m 6/7, 672m 8/9, 675 m/0 or 678m 1/2, etc., the concentration of the trioctyl phosphate is 210-230m 3/4, such as 212m 5/6, 215m 7/8, 218m 9/, 220m 0/1, 222m 2/3, 225m 4/5, 228m 6/7 or 229m 8/9, etc., and the concentration of the 2-ethylanthraquinone is 110-130g/, such as 112 g/0, 115 g/1, 118 g/2, 120 g/2, 122 g/125 g/2, etc.

Preferably, the temperature of the hydrogen gas and the working solution after preheating in step (2) is 55-75 deg.C, such as 56 deg.C, 57 deg.C, 58 deg.C, 59 deg.C, 60 deg.C, 62 deg.C, 65 deg.C, 68 deg.C, 70 deg.C, 72 deg.C or 74 deg.C.

Preferably, the reaction of step (2) is carried out at 20-100 deg.C, such as 25 deg.C, 26 deg.C, 28 deg.C, 30 deg.C, 35 deg.C, 40 deg.C, 50 deg.C, 60 deg.C, 70 deg.C, 80 deg.C or 90 deg.C.

Preferably, before introducing the hydrogen and the working solution in step (2), the catalyst is further subjected to reduction activation treatment, specifically: heating the high gravity rotary packed bed to 50-80 deg.C, such as 55 deg.C, 60 deg.C, 65 deg.C, 70 deg.C, 75 deg.C or 78 deg.C, introducing hydrogen to reduce and activate for 1-24h, such as 2h, 3h, 5h, 8h, 10h, 12h, 15h, 18h or 20h, and exhausting with nitrogen.

Preferably, the post-processing of step (2) comprises: oxidizing, extracting and purifying the liquid-phase reaction product to obtain a hydrogen peroxide product; condensing the gas phase reaction product to obtain gas phase and liquid phase, mixing the liquid phase and the liquid phase reaction product, and exhausting the gas.

Preferably, the liquid-phase reaction product obtained in the step (2) is returned to the step (1) to be mixed with the working fluid, or the liquid-phase reaction product obtained in the step (2) is used as the working fluid of the next hypergravity rotating packed bed. The obtained liquid phase reaction product can be subjected to a circulating reaction or enter the next hypergravity rotating packed bed to be subjected to a hydrogenation reaction again, so that better hydrogenation efficiency and space-time yield are achieved.

As a preferred technical scheme, the method comprises the following steps:

(1) filling a catalyst into the wall of the supergravity rotating packed bed reactor, heating the supergravity rotating packed bed to 80 ℃, introducing hydrogen to carry out reduction activation for 8 hours, and exhausting nitrogen; rotating the super-gravity rotating packed bed at the speed of 0-3000 r/min;

(2) spraying a working solution with the temperature of 55-75 ℃ from a liquid inlet pipe onto the inner wall of a rotating reactor, enabling a hydrogen gas with the temperature of 55-75 ℃ to flow axially or radially through a catalyst in the reactor wall, and carrying out forward-flow, cross-flow or countercurrent contact reaction on the reactor wall, wherein the hydrogen flow is 1-100L/min, the working solution flow is 1-100L/min, the volume ratio of hydrogen to the working solution is 10:1-15:1, the working solution consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, the concentration of the 2-ethyl anthraquinone is 110-130 g/L, the reaction temperature is 20-100 ℃, controlling the pressure in a supergravity rotating packed bed to be 0.1-10MPa in the reaction process, and enabling the obtained liquid phase reaction products and gas products to flow out through a through hole;

(3) collecting liquid phase reaction products, oxidizing and extracting the liquid phase reaction products to obtain hydrogen peroxide products; condensing the gas phase reaction product to obtain gas and liquid phase, exhausting the gas, and mixing the liquid phase with the liquid phase reaction product.

The preparation method of the hydrogen peroxide provided by the invention takes 2-ethyl anthraquinone and hydrogen as raw materials, takes heavy aromatic hydrocarbon and trioctyl phosphate as solvents, takes a granular supported palladium catalyst as a catalyst, and carries out hydrogenation reaction at the temperature of 20-100 ℃ and the pressure of 0.1-10 MPa.

The specific reaction process for preparing hydrogen peroxide by the anthraquinone method is as follows:

after the reaction is finished, the hydrogenated liquid is sent to an oxidation device for oxidation, and the generated reaction is as follows:

and (4) carrying out an extraction process on the oxidized liquid to obtain a hydrogen peroxide product. In the process, the hydrogenation liquid can be sampled and analyzed, and the hydrogenation efficiency can be calculated.

In conclusion, the method of the invention is to synthesize the hydroanthraquinone by catalytic hydrogenation under the condition of the high gravity generated by the high-speed rotation of the high-gravity rotating packed bed reactor, the oxidation process of the hydroanthraquinone is consistent with that of the traditional method, and finally the hydrogen peroxide is prepared by extraction.

In addition, in addition to the preparation of hydrogen peroxide from 2-ethylanthraquinone, the preparation of hydrogen peroxide from 2-tert-butylanthraquinone, 2-tert-amylanthraquinone or 2-isobutylanthraquinone can also be carried out on the system provided by the present invention.

Compared with the prior art, the invention has the beneficial effects that:

the supergravity rotating packed bed in the system for preparing hydrogen peroxide by the anthraquinone process provided by the invention is the core equipment for preparing hydrogen peroxide products: the synthetic hydroanthraquinone is a centrifugal force field generated by the rotation of a supergravity rotating packed bed, a liquid film becomes thin, liquid drops become small and reach the nanometer and micron level, and a huge phase interface is generated; the updating speed of the liquid film is also greatly improved; the contact between gas and liquid is more sufficient, so that the hydrogenation process is greatly enhanced, the production capacity of the reactor can be improved by more than 30%, the bed resistance is small, and meanwhile, the phenomenon of agglomeration due to excessive hydrogenation cannot occur due to small retention time, and the side reaction is strictly controlled.

Compared with the traditional process, the method for producing the hydrogen peroxide by the anthraquinone process can effectively improve the efficiency of the reactor and fully utilize the catalyst, thereby improving the productivity of the hydrogen peroxide.

The reaction time of the high-gravity rotating packed bed and the method for preparing hydrogen peroxide by using the same provided by the invention is shortened by 50% compared with that of a fixed bed reactor, the hydrogenation efficiency can reach 6 g/L, the mass transfer efficiency can be improved by 50% -200%, the cost is only 10% of that of the fixed bed reactor, the occupied area is obviously reduced, the operation is simple, and the investment is low.

Drawings

FIG. 1 is a schematic diagram of a system for producing hydrogen peroxide by the anthraquinone process provided in example 2.

Fig. 2 is a schematic structural diagram of a counter-current supergravity rotating packed bed for anthraquinone hydrogenation catalytic reaction in a process for producing hydrogen peroxide by an anthraquinone method according to an embodiment of the present invention.

FIG. 3 is a schematic structural diagram of a cocurrent supergravity rotating packed bed for anthraquinone hydrogenation catalytic reaction in the process of producing hydrogen peroxide by an anthraquinone method according to an embodiment of the present invention.

FIG. 4 shows the hydrogenation efficiency and space-time yield of the hydrogenation solution for different cycle times as provided in example 11.

Wherein, in fig. 1: 1-a mass flow controller; 2-a first preheating furnace, 3-a three-way ball valve, 4-a hypergravity rotating packed bed and 5-a second preheating furnace; 6-condenser, 7-product storage tank, 8-liquid taking port, 9-pressure reducing valve, 10-pressure gauge, 11-pump, 12-working liquid storage tank and 13-lofting port;

in fig. 2: 21-liquid inlet pipe, 22-gas outlet, 23-gas inlet, 24-shell, 25-reactor, 26-liquid drop, 27-filler, 28-liquid outlet, 29-bearing, 210-motor;

in fig. 3: 31-liquid inlet pipe, 32-gas inlet, 33-shell, 34-reactor, 35-liquid drop, 36-filler, 37-gas-liquid outlet, 38-bearing and 39-motor.

Detailed Description

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

Example 1

A system for preparing hydrogen peroxide by an anthraquinone method comprises a hypergravity rotating packed bed 4, a gas conveying device, a liquid conveying device, a first preheating furnace 2, a second preheating furnace 5, a condenser 6, a product storage tank and a liquid inlet pipe;

the hypergravity rotating packed bed 4 comprises a shell, a reactor and a rotating device, wherein the reactor is positioned in the shell, the wall of the reactor is filled with a hydrogenation catalyst, the wall of the reactor is provided with through holes, and the reactor is communicated with the shell through the through holes; the rotating device is connected with the reactor and is used for driving the reactor to rotate;

the through holes are circular and are provided with a plurality of through holes; a metal wire mesh is arranged in the through hole; the interval between the adjacent through holes is 1 mm; the reactor is a hollow cylinder; the wall thickness of the cylinder is 21 mm; the radius of the cylinder is 73 mm; the shell is in a hollow cylinder shape, and the radius of the shell is 100 mm;

the top of the reactor of the supergravity rotating packed bed 4 is provided with a liquid inlet, and the bottom of the shell is provided with a liquid outlet; the top of the shell of the supergravity rotating packed bed 4 and the top of the reactor are respectively provided with a gas inlet; the gas outlet may be incorporated with the liquid outlet or provided on the housing or reactor;

the gas conveying device comprises a hydrogen storage tank and a nitrogen storage tank, the hydrogen storage tank and the nitrogen storage tank are respectively connected with one end of a gas conveying pipeline through valves, the other end of the gas conveying pipeline is connected with each gas inlet through a valve, and the first preheating furnace 2 is arranged on the gas conveying pipeline;

the liquid conveying device comprises a working liquid storage tank 12 and a pump, the working liquid storage tank 12 is communicated with a liquid inlet arranged on the reactor through a liquid conveying pipeline, and the pump and the second preheating furnace 5 are arranged on the liquid conveying pipeline;

one end of the liquid inlet pipe is opened, the other end of the liquid inlet pipe is closed, the open end of the liquid inlet pipe is connected with the working liquid storage tank through a pump, the closed end of the liquid inlet pipe extends into the center of the reactor, and a slit is arranged on the wall of the liquid inlet pipe extending into the reactor and used for spraying the working liquid onto the inner wall of the reactor;

the inlet of the condenser 6 is connected with the gas outlet; the product storage tank is connected with the liquid outlet of the condenser 6 and the liquid outlet of the shell.

The method for preparing hydrogen peroxide by using the system comprises the following steps:

(1) filling a catalyst into the wall of the supergravity rotating packed bed reactor, heating the supergravity rotating packed bed to 50-80 ℃, introducing hydrogen to carry out reduction activation for 1-24h, and exhausting nitrogen; rotating the super-gravity rotating packed bed at the speed of 0-3000 r/min;

(2) spraying a working solution with the temperature of 55-75 ℃ from a liquid inlet pipe onto the inner wall of a rotating reactor, enabling a hydrogen gas with the temperature of 55-75 ℃ to flow axially or radially through a catalyst in the reactor wall, and carrying out forward-flow, cross-flow or countercurrent contact reaction on the reactor wall, wherein the hydrogen flow is 1-100L/min, the working solution flow is 1-100L/min, the volume ratio of hydrogen to the working solution is 10:1-15:1, the working solution consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, the concentration of the 2-ethyl anthraquinone is 110-130 g/L, the reaction temperature is 20-100 ℃, controlling the pressure in a supergravity rotating packed bed to be 0.1-10MPa in the reaction process, and enabling the obtained liquid phase reaction products and gas products to flow out through a through hole;

(3) collecting liquid phase reaction products, oxidizing and extracting the liquid phase reaction products to obtain hydrogen peroxide products; condensing the gas phase reaction product to obtain gas and liquid phase, exhausting the gas, and mixing the liquid phase with the liquid phase reaction product.

Example 2

A circulation system for preparing hydrogen peroxide by anthraquinone process is shown in figure 1. The system is the same as that described in example 1, except that the product tank is also connected to the working fluid tank 12.

The method for preparing hydrogen peroxide by using the system comprises the following steps:

(1) filling a catalyst into the wall of the supergravity rotating packed bed reactor, heating the supergravity rotating packed bed to 50-80 ℃, introducing hydrogen to carry out reduction activation for 1-24h, and exhausting nitrogen; rotating the super-gravity rotating packed bed at the speed of 0-3000 r/min;

(2) spraying a working solution with the temperature of 55-75 ℃ from a liquid inlet pipe onto the inner wall of a rotating reactor, enabling a hydrogen gas with the temperature of 55-75 ℃ to flow axially or radially through a catalyst in the reactor wall, and carrying out forward-flow, cross-flow or countercurrent contact reaction on the reactor wall, wherein the hydrogen flow is 1-100L/min, the working solution flow is 1-100L/min, the volume ratio of hydrogen to the working solution is 10:1-15:1, the working solution consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, the concentration of the 2-ethyl anthraquinone is 110-130 g/L, the reaction temperature is 20-100 ℃, controlling the pressure in a supergravity rotating packed bed to be 0.1-10MPa in the reaction process, and enabling the obtained liquid phase reaction products and gas products to flow out through a through hole;

(3) mixing the liquid-phase reaction product with working solution, continuing to perform the step (1) and the step (2), oxidizing and extracting the final liquid-phase reaction product to obtain a hydrogen peroxide product; condensing the gas phase reaction product to obtain gas and liquid phase, exhausting the gas, and mixing the liquid phase with the liquid phase reaction product.

The hypergravity rotating packed bed may be provided with only one gas inlet and only one gas outlet as shown in fig. 2 and 3. FIG. 2 is a schematic structural diagram of a counter-current supergravity rotating packed bed for anthraquinone hydrogenation catalytic reaction in a process for producing hydrogen peroxide by an anthraquinone method, wherein a gas inlet 23 is arranged on a shell 24, and a gas outlet 22 is arranged on a reactor 25; fig. 3 is a schematic structural diagram of a co-current supergravity rotating packed bed for anthraquinone hydrogenation catalytic reaction in the process of producing hydrogen peroxide by using an anthraquinone method, wherein a gas inlet 32 is arranged on a reactor 34, and a gas outlet and a liquid outlet share one port, namely a gas-liquid outlet 37, which is arranged on a shell 33.

Example 3

A multi-stage reaction system for preparing hydrogen peroxide by an anthraquinone process comprises three hypergravity rotating packed beds 4 (a first hypergravity rotating packed bed, a second hypergravity rotating packed bed and a third hypergravity rotating packed bed), a gas conveying device, a liquid conveying device, a first preheating furnace 2, a second preheating furnace 5, a condenser 6, a product storage tank and a liquid inlet pipe;

each high-gravity rotating packed bed 4 comprises a shell, a reactor and a rotating device, wherein the reactor is positioned in the shell, the wall of the reactor is filled with a hydrogenation catalyst, and is provided with through holes, and the reactor is communicated with the shell through the through holes; the rotating device is connected with the reactor and is used for driving the reactor to rotate;

the through holes are circular and are provided with a plurality of through holes; a metal wire mesh is arranged in the through hole; the interval between the adjacent through holes is 1 mm; the reactor is a hollow cylinder; the wall thickness of the cylinder is 21 mm; the radius of the cylinder is 73 mm; the shell is in a hollow cylinder shape, and the radius of the shell is 100 mm;

the top of the reactor of each hypergravity rotating packed bed 4 is provided with a liquid inlet, and the bottom of the shell is provided with a liquid outlet; the top of the shell of each super-gravity rotating packed bed 4 and the top of the reactor are respectively provided with a gas inlet; the gas outlet may be incorporated with the liquid outlet or provided on the housing or reactor;

the liquid outlet of the hypergravity rotating packed bed is connected with the liquid inlet of the hypergravity rotating packed bed; the liquid outlet of the hypergravity rotating packed bed is connected with the liquid inlet of a third liquid packed bed;

the gas conveying device comprises a hydrogen storage tank and a nitrogen storage tank, the hydrogen storage tank and the nitrogen storage tank are respectively connected with one end of a gas conveying pipeline through valves, the other end of the gas conveying pipeline is connected with a gas inlet of each supergravity rotary packed bed 4 through a valve, and the first preheating furnace 2 is arranged on the gas conveying pipeline;

the liquid conveying device comprises a working liquid storage tank 12 and a pump, the working liquid storage tank 12 is communicated with a liquid inlet arranged on the supergravity rotary packed bed reactor through a liquid conveying pipeline, and the pump and the second preheating furnace 5 are arranged on the liquid conveying pipeline;

the reactor comprises three liquid inlet pipes, wherein one end of each liquid inlet pipe is opened, the other end of each liquid inlet pipe is closed, the open end of each liquid inlet pipe is connected with a working liquid storage tank through a pump, the closed end of each liquid inlet pipe extends into the center of the reactor, and a slit is formed in the wall of each liquid inlet pipe extending into the reactor and used for spraying working liquid onto the inner wall of the reactor;

the inlet of the condenser 6 is connected with the liquid outlet of each supergravity rotating packed bed 4; the product storage tank is connected with a liquid outlet of the condenser 6 and a liquid outlet of the hypergravity rotating packed bed shell.

The method for preparing hydrogen peroxide by using the system comprises the following steps:

(1) filling catalysts into the walls of the three high-gravity rotating packed bed reactors, heating the three high-gravity rotating packed bed reactors to 50-80 ℃, introducing hydrogen to carry out reduction activation for 1-24h, and exhausting nitrogen; rotating the three hypergravity rotating packed beds at the speed of 0-3000 r/min;

(2) spraying a working solution with the temperature of 55-75 ℃ from a liquid inlet pipe onto the inner wall of a reactor rotating by a first hypergravity rotating packed bed, enabling a hydrogen gas with the temperature of 55-75 ℃ to flow axially or radially through a catalyst in the reactor wall, and enabling the hydrogen gas and the catalyst to perform forward-current, cross-current or countercurrent contact reaction on the reactor wall, wherein the hydrogen flow is 1-100L/min, the working solution flow is 1-100L/min, the volume ratio of the hydrogen gas to the working solution is 10:1-15:1, the working solution consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-minus 680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, the concentration of the 2-ethyl anthraquinone is 110-minus 130 g/L, the reaction temperature is 20-100 ℃, controlling the pressure in the hypergravity rotating packed bed to be 0.1-0.56MPa in the reaction process, and obtaining a first reaction product and a first liquid phase through-phase reaction product which flows out;

(3) spraying a first liquid-phase reaction product from a liquid inlet pipe onto the inner wall of a reactor rotating by a second super-gravity rotating packed bed, enabling a hydrogen gas at the temperature of 55-75 ℃ to flow axially or radially through a catalyst in the reactor wall, and enabling the hydrogen gas to flow through the catalyst in the reactor wall in a forward, cross-flow or reverse-flow contact reaction, wherein the hydrogen flow is 1-100L/min, the working liquid flow is 1-100L/min, the volume ratio of the hydrogen gas to the working liquid is 10:1-15:1, the working liquid consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, the concentration of the 2-ethyl anthraquinone is 110-130 g/L, the reaction temperature is 20-100 ℃, controlling the pressure in the second super-gravity rotating packed bed to be 0.1-10MPa in the reaction process, and enabling a second liquid-phase reaction product to flow out through a through hole;

(4) spraying a second liquid-phase reaction product from a liquid inlet pipe onto the inner wall of a reactor rotating by a third super-gravity rotating packed bed, enabling the hydrogen with the temperature of 55-75 ℃ to flow axially or radially through a catalyst in the reactor wall, and enabling the hydrogen to flow through the catalyst in the reactor wall in a forward, cross-flow or reverse-flow contact reaction, wherein the hydrogen flow is 1-100L/min, the working fluid flow is 1-100L/min, the volume ratio of the hydrogen to the working fluid is 10:1-15:1, the working fluid consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, the concentration of the 2-ethyl anthraquinone is 110-130 g/L, the reaction temperature is 20-100 ℃, controlling the pressure in the third super-gravity rotating packed bed to be 0.1-0.56MPa in the reaction process, and enabling the third liquid-phase reaction product to flow out through a through hole;

(7) and oxidizing, extracting and purifying the third liquid-phase reaction product to obtain a hydrogen peroxide product.

Example 4

A catalytic hydrogenation reaction using the system of example 1, the method comprising the steps of:

(1) 50m L Raschig ring Pd/Al is filled in a packing cavity of a supergravity rotating packed bed 4 reactor₂O₃Heating the supergravity rotating packed bed 4 to 80 deg.C, introducing hydrogen to reduce and activate for 8h, and exhausting with nitrogen;

(2) introducing hydrogen and working liquid with the temperature of 55 ℃ into a shell and a reactor of a hypergravity rotating packed bed 4 respectively, wherein the working liquid enters the reactor through a liquid inlet arranged in the center of the top of the reactor, the volume ratio of the hydrogen to the working liquid is 12:1, the working liquid consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 78:22, the concentration of the heavy aromatic hydrocarbon is 670m L/L, the concentration of the trioctyl phosphate is 220m L/L, and 2-The concentration of the ethyl anthraquinone is 120 g/L, and the liquid air speed is 12h^-1Space velocity of hydrogen gas of 120h^-1；

(3) The hypergravity rotating packed bed 4 is rotated at the speed of 900r/min, the pressure in the hypergravity rotating packed bed 4 is controlled to be 0.3MPa, hydrogen and working solution are in countercurrent contact reaction on the surface of the catalyst, and the obtained liquid phase reaction product (hydrogenated liquid) and gas phase reaction product flow out through the through hole.

After the hydrogenation reaction is finished, the hydrogenated liquid is discharged from a liquid outlet of the reactor and transferred into an oxidation device (an oxidation tower) to continue the oxidation reaction to generate the anthraquinone and the hydrogen peroxide. And (3) separating the hydrogen peroxide and the anthraquinone working solution from the oxidation product in extraction equipment, and purifying to obtain a hydrogen peroxide product. The separated anthraquinone working solution can be continuously recycled. The oxidation, extraction, purification, working solution treatment and circulation operations are the same as those in the prior art and are not described in detail.

The technological conditions and processes of the comparison method are completely the same, and the difference is only that the hypergravity rotating packed bed 4 is replaced by a traditional vertical reactor which transfers mass by gravity.

Determination of hydrogenation efficiency:

taking 5m L hydrogenated liquid by a pipette into a 500m L separating funnel, adding 20m L aromatic hydrocarbon and 10m L10% phosphoric acid, inserting a gas dispersion tube into the separating funnel, introducing oxygen for about 15 minutes, extracting hydrogen peroxide in the hydrogen peroxide by using distilled water, 20m L each time, extracting for 4 times in total, putting a lower layer aqueous solution into a triangular flask until no hydrogen peroxide exists in an extraction liquid, adding 20m L sulfuric acid into the extraction liquid, titrating by using a potassium permanganate standard solution until the solution becomes reddish and the end point is that the solution does not fade for 30 seconds.

Calculating the hydrogenation efficiency (hydrogen efficiency for short) according to the prior public:

B＝17CV/5

in the formula, B is hydrogenation efficiency with unit g/L, C is potassium permanganate standard solution concentration mol/L, and V is potassium permanganate consumption volume m L by titration.

The hydrogen efficiency of the obtained hydrogenated liquid was measured to be 4.2 g/L by using a conventional vertical reactor, and was measured to be 6.2 g/L by using the method described in example 4 and reacting under the condition of supergravity, and the hydrogen efficiency was increased by 45.2%.

Example 5

A method for preparing hydrogen peroxide by an anthraquinone process, which is the same as that described in example 4 except that hydrogen gas is introduced into the reactor from a gas inlet at the top of the reactor.

The technological conditions and processes of the comparison method are completely the same, and the difference is only that the hypergravity rotating packed bed 4 is replaced by a traditional vertical reactor which transfers mass by gravity.

In the method, hydrogen and working solution are in cocurrent flow to contact and react on the surface of the catalyst, and the hydrogen efficiency is 5.5 g/L which is slightly lower than that of the example 1 by adopting the hydrogen efficiency measuring method which is the same as the example 4.

Example 6

A process for preparing hydrogen peroxide by anthraquinone method features use of Pd/Al as catalyst₂O₃The procedure of example 4 was repeated except that the reaction temperature of hydrogen and the working solution was 60 ℃ in the case of phi 2 × 5mm (phi means diameter) strip.

The technological conditions and processes of the comparison method are completely the same, and the difference is only that the hypergravity rotating packed bed 4 is replaced by a traditional vertical reactor which transfers mass by gravity.

The hydrogen efficiency of the conventional vertical reactor was 3.4 g/L, as measured by the same hydrogen efficiency measurement method as in example 4, and the hydrogen efficiency was 4.7 g/L, which was increased by 38.2% as compared with the conventional vertical reactor, using the method described in example 6.

Example 7

A process for preparing hydrogen peroxide by anthraquinone method features that the catalyst used is spherical Pd/SiO₂The procedure of example 4 was repeated except that the reaction temperature of hydrogen gas and the working solution was 55 ℃ and Φ 2mm (Φ means diameter).

The technological conditions and processes of the comparison method are completely the same, and the difference is only that the hypergravity rotating packed bed 4 is replaced by a traditional vertical reactor which transfers mass by gravity.

The hydrogen efficiency of the conventional vertical reactor was 3.5 g/L, as measured by the same hydrogen efficiency measurement method as in example 4, and the hydrogen efficiency was 4.4 g/L, which was increased by 25.7% as compared with the conventional vertical reactor, using the method described in example 7.

Example 8

A method for preparing hydrogen peroxide by an anthraquinone process, said method comprising the steps of:

(1) filling a catalyst into the wall of the supergravity rotating packed bed reactor, heating the supergravity rotating packed bed to 50 ℃, introducing hydrogen to carry out reduction activation for 24 hours, and exhausting nitrogen; rotating the hypergravity rotating packed bed at 3000 r/min;

(2) spraying working liquid with the temperature of 55 ℃ from a liquid inlet pipe onto the inner wall of a rotating reactor, enabling a hydrogen shaft with the temperature of 75 ℃ to flow through a catalyst in the wall of the reactor, and enabling a hydrogen shaft with the temperature of 75 ℃ to flow on the wall of the reactor to perform forward-flow, cross-flow or countercurrent contact reaction, wherein the hydrogen flow is 100L/min, the working liquid flow is 1L/min, the working liquid consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 77:23, the concentration of the heavy aromatic hydrocarbon is 675m L/L, the concentration of the trioctyl phosphate is 225m L/L, the concentration of the 2-ethyl anthraquinone is 115 g/L, the reaction temperature is 20 ℃, the pressure in a hypergravity rotating packed bed is controlled to be 0.1MPa in the reaction process, and the obtained liquid-phase reaction product and gas-phase reaction product flow out through;

(3) collecting liquid phase reaction products, oxidizing and extracting the liquid phase reaction products to obtain hydrogen peroxide products; condensing the gas phase reaction product to obtain gas and liquid phase, exhausting the gas, and mixing the liquid phase with the liquid phase reaction product.

The technological conditions and processes of the comparison method are completely the same, and the difference is only that the hypergravity rotating packed bed 4 is replaced by a traditional vertical reactor which transfers mass by gravity.

The hydrogen efficiency of the conventional vertical reactor was 6 g/L, as measured by the same hydrogen efficiency measurement method as in example 4, and the hydrogen efficiency of the reactor was 8 g/L, which was increased by 25% as compared with the conventional vertical reactor, using the method described in example 8.

Example 9

A method for preparing hydrogen peroxide by an anthraquinone process, said method comprising the steps of:

(1) filling a catalyst into the wall of the supergravity rotating packed bed reactor, heating the supergravity rotating packed bed to 80 ℃, introducing hydrogen to carry out reduction activation for 1h, and exhausting nitrogen; rotating the high-gravity rotating packed bed at the speed of 1000 r/min;

(2) spraying a working solution with the temperature of 75 ℃ from a liquid inlet pipe onto the inner wall of a rotating reactor, enabling hydrogen with the temperature of 55 ℃ to radially flow through a catalyst in the wall of the reactor, and carrying out forward-flow and cross-flow contact reaction on the wall of the reactor, wherein the hydrogen flow is 100L/min, the working solution flow is 1L/min, the working solution consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 80:20, the concentration of the heavy aromatic hydrocarbon is 660m L/L, the concentration of the trioctyl phosphate is 230m L/L, the concentration of the 2-ethyl anthraquinone is 110 g/L, the reaction temperature is 100 ℃, the pressure in a super-gravity rotating packed bed is controlled to be 10MPa in the reaction process, and the obtained liquid-phase reaction product and gas-phase reaction product flow out through a through hole;

(3) collecting liquid phase reaction products, oxidizing and extracting the liquid phase reaction products to obtain hydrogen peroxide products; condensing the gas phase reaction product to obtain gas and liquid phase, exhausting the gas, and mixing the liquid phase with the liquid phase reaction product.

The technological conditions and processes of the comparison method are completely the same, and the difference is only that the hypergravity rotating packed bed 4 is replaced by a traditional vertical reactor which transfers mass by gravity.

The hydrogen efficiency of the conventional vertical reactor was 5 g/L, as measured by the same hydrogen efficiency measurement method as in example 4, and 9 g/L, as measured by the method described in example 9, increased by 80% as compared with the conventional vertical reactor.

Example 10

A method for preparing hydrogen peroxide by an anthraquinone process, said method comprising the steps of:

(1) filling a catalyst into the wall of the supergravity rotating packed bed reactor, heating the supergravity rotating packed bed to 60 ℃, introducing hydrogen to carry out reduction activation for 12 hours, and exhausting nitrogen; rotating the hypergravity rotating packed bed at the speed of 5 r/min;

(2) spraying working liquid with the temperature of 60 ℃ from a liquid inlet pipe to the inner wall of a rotating reactor, enabling a hydrogen shaft with the temperature of 60 ℃ to flow through a catalyst in the wall of the reactor, and carrying out countercurrent contact reaction on the working liquid and the catalyst on the wall of the reactor, wherein the hydrogen flow is 50L/min, the working liquid flow is 50L/min, the working liquid consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25, the concentration of the heavy aromatic hydrocarbon is 680m L/L, the concentration of the trioctyl phosphate is 210m L/L, the concentration of the 2-ethyl anthraquinone is 130 g/L, the reaction temperature is 70 ℃, the pressure in a supergravity rotating packed bed is controlled to be 5MPa in the reaction process, and the obtained liquid-phase reaction product and gas-phase reaction product flow out through holes;

(3) collecting liquid phase reaction products, oxidizing and extracting the liquid phase reaction products to obtain hydrogen peroxide products; condensing the gas phase reaction product to obtain gas and liquid phase, exhausting the gas, and mixing the liquid phase with the liquid phase reaction product.

The technological conditions and processes of the comparison method are completely the same, and the difference is only that the hypergravity rotating packed bed 4 is replaced by a traditional vertical reactor which transfers mass by gravity.

The hydrogen efficiency of the conventional vertical reactor was 6 g/L, as measured by the same hydrogen efficiency measurement method as in example 4, and the hydrogen efficiency of the reactor was 8 g/L, which was increased by 33% as compared with the conventional vertical reactor, using the method described in example 10.

Example 11

The process conditions for the preparation of hydrogen peroxide on the recycle system described in example 2 are the process conditions described in example 4, the hydrogenation efficiency and space time yield of the hydrogenation liquid with different recycle times are shown in fig. 4, it can be seen that the hypergravity rotating packed bed has very high space time yield without the recycle operation, but the hydrogenation efficiency (hydrogen efficiency) is low, and by increasing the recycle time, although the hydrogen efficiency is improved, the space time yield can be found to be reduced significantly. In addition, the space-time yield of the hypergravity reactor (27.9g (H)₂O₂) the/L (cat.) H is much higher than the space-time yield of a fixed bed reactor (12.7-16.5g (H)₂O₂) The continuous series of super-gravity rotating packed beds which are not operated circularly can not only improve the space time of the process productionThe yield can also ensure that reasonable hydrogen efficiency is obtained.

The applicant declares that the above description is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the scope and disclosure of the present invention.

Claims (34)

1. A system for preparing hydrogen peroxide by an anthraquinone process is characterized by comprising a hypergravity rotating packed bed, a gas conveying device, a liquid conveying device, a first preheating device and a second preheating device;

the high-gravity rotating packed bed comprises a shell, a reactor and a rotating device, wherein the reactor is positioned in the shell, a catalyst is filled in the wall of the reactor, a through hole is formed in the wall of the reactor, and the reactor is communicated with the shell through the through hole; the rotating device is connected with the reactor and is used for driving the reactor to rotate;

the gas conveying device is communicated with a gas inlet arranged on the reactor and/or the shell through a gas conveying pipeline, and the gas conveying pipeline is provided with a first preheating device;

the liquid conveying device is communicated with a liquid inlet arranged on the reactor through a liquid conveying pipeline, and a second preheating device is arranged on the liquid conveying pipeline;

the shell is provided with a gas outlet and a liquid outlet;

the super-gravity rotating bed is horizontal;

the system also comprises a spraying device, wherein the spraying device comprises a liquid inlet pipe, one end of the liquid inlet pipe is opened, the other end of the liquid inlet pipe is closed, the open end of the liquid inlet pipe is connected with the liquid conveying device, the closed end of the liquid inlet pipe extends into the reactor, a through hole is formed in the wall of the liquid inlet pipe extending into the reactor, and the spraying device is used for spraying the working liquid onto the wall of the reactor;

a reticular structure is arranged in the through hole of the reactor;

the system comprises at least two series-connected hypergravity rotating packed beds, wherein a liquid outlet of the previous hypergravity rotating packed bed is connected with a liquid inlet of the next hypergravity rotating packed bed; the gas conveying device is respectively connected with the gas inlets on the at least two hypergravity rotating packed beds.

2. The system of claim 1, wherein the material of the mesh structure is selected from any one of metal, silica gel, or polymer material, or a combination of at least two of the metal, silica gel, or polymer material.

3. The system of claim 2, wherein the mesh structure is rebar.

4. The system of claim 1, wherein the plurality of through holes are spaced 1mm to 10mm apart.

5. The system of claim 1, wherein the through-hole is circular.

6. The system of claim 1, wherein the reactor is a hollow cylinder having a wall with through holes.

7. The system of claim 6, wherein the cylinder has a wall thickness of 5-50 mm.

8. The system of claim 6, wherein the cylinder has a radius of 5-50 mm.

9. The system of claim 1, wherein the housing is in the shape of a hollow cylinder, the housing having a radius of 50-500 mm.

10. The system of claim 1, wherein the liquid delivery device comprises a working liquid reservoir and a pump, the working liquid reservoir being connected to the liquid inlet by the pump.

11. The system of claim 1, wherein the gas delivery device comprises a hydrogen tank and a nitrogen tank, both connected to the gas inlet via a first pre-heating device.

12. The system of claim 1, further comprising a condensing device and a product storage tank, wherein an inlet of the condensing device is connected to the liquid outlet; the product storage tank is connected with the liquid outlet of the condensing device and the liquid outlet of the shell.

13. The system of claim 1, wherein the system is provided with two gas inlets and cooperating sealing pistons, one on the housing and the other on the reactor.

14. The system of claim 1, comprising 1-100 series-connected super-gravity rotating packed beds.

15. A method for preparing hydrogen peroxide by anthraquinone process, characterized in that the method uses the system of any one of claims 1 to 14 to perform hydrogenation reaction of anthraquinone.

16. The method according to claim 15, characterized in that it comprises the steps of:

(1) filling a hydrogenation catalyst in the wall of the high-gravity rotating packed bed reactor, and rotating the high-gravity rotating packed bed at the speed of 1000-;

(2) introducing both preheated hydrogen and working liquid into the reactor, or respectively introducing the hydrogen and the working liquid into a shell of the supergravity rotating packed bed and the reactor; controlling the pressure in the hypergravity rotating packed bed to be 0.1-10MPa, so that the hydrogen and the working solution are in parallel flow, cross flow or countercurrent contact reaction on the surface of the catalyst, the obtained liquid phase reaction product and gas phase reaction product flow out through the through hole, and the liquid phase reaction product is post-treated to obtain the hydrogen peroxide product.

17. The method of claim 16, wherein the loading of the catalyst in step (1) is controlled to be 20-200m L.

18. The method according to claim 16, wherein the catalyst in step (1) is a supported palladium catalyst, and the carrier in the supported palladium catalyst is a non-spherical granular carrier having a hollow structure.

19. The method of claim 18, wherein the carrier is any one of or a combination of at least two of a raschig ring, a wheel ring, a porous strip, or a porous ring.

20. The method of claim 19, wherein the carrier is a raschig ring.

21. The process of claim 18 wherein the supported palladium catalyst has a palladium loading of from 0.01 to 1 weight percent.

22. The method of claim 18, wherein the catalyst of step (1) is an alumina composite palladium black catalyst.

23. The method of claim 22, wherein the palladium black is present in the alumina composite palladium black catalyst in an amount of 0.1 to 5% by weight.

24. The method of claim 22, wherein the alumina composite palladium black catalyst is spherical with a diameter of 1-100mm, has a length-to-diameter ratio of 1:1-1:10, and has a Raschig ring shape with a diameter of 1-100mm, or has a clover shape with the same size.

25. The method of claim 16, wherein the working fluid and hydrogen gas of step (2) are introduced by: the working liquid is sprayed out from the liquid inlet pipe and sprinkled on the inner wall of the rotating reactor, the hydrogen axially or radially flows through the catalyst in the wall of the reactor, and the hydrogen and the catalyst are in concurrent, cross-flow or countercurrent contact on the wall of the reactor.

26. The method of claim 25, wherein the hydrogen flow rate is 1-100L/min and the working fluid flow rate is 1-100L/min.

27. The method of claim 26, wherein the volumetric ratio of hydrogen to the working fluid in the hypergravity rotating packed bed of step (2) is 10:1 to 15: 1.

28. The method as claimed in claim 16, wherein the working solution in step (2) comprises heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, and the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, and the concentration of the 2-ethyl anthraquinone is 110-130 g/L.

29. The method of claim 16, wherein the temperature of the preheated hydrogen gas and the working fluid in step (2) is 55-75 ℃.

30. The method of claim 16, wherein the reaction of step (2) is carried out at 20-100 ℃.

31. The method according to claim 16, wherein before introducing the hydrogen gas and the working solution in step (2), the catalyst is subjected to reduction activation treatment, specifically: heating the hypergravity rotating packed bed to 50-80 ℃, introducing hydrogen to carry out reduction activation for 1-24h, and exhausting nitrogen.

32. The method of claim 16, wherein the post-processing of step (2) comprises: oxidizing, extracting and purifying the liquid-phase reaction product to obtain a hydrogen peroxide product; condensing the gas phase reaction product to obtain gas phase and liquid phase, mixing the liquid phase and the liquid phase reaction product, and exhausting the gas.

33. The method of claim 16, wherein the liquid-phase reaction product obtained in step (2) is returned to step (1) to be mixed with the working fluid, or the liquid-phase reaction product obtained in step (2) is used as the working fluid for the next high-gravity rotating packed bed.

34. The method according to claim 16, characterized in that it comprises the steps of:

(1) filling a catalyst into the wall of the supergravity rotating packed bed reactor, heating the supergravity rotating packed bed to 50-80 ℃, introducing hydrogen to carry out reduction activation for 1-24h, and exhausting nitrogen; rotating the high-gravity rotating packed bed at the speed of 1000-;

(2) spraying a working solution with the temperature of 55-75 ℃ from a liquid inlet pipe onto the inner wall of a rotating reactor, enabling a hydrogen gas with the temperature of 55-75 ℃ to flow axially or radially through a catalyst in the reactor wall, and carrying out forward-flow, cross-flow or countercurrent contact reaction on the reactor wall, wherein the hydrogen flow is 1-100L/min, the working solution flow is 1-100L/min, the volume ratio of hydrogen to the working solution is 10:1-15:1, the working solution consists of heavy aromatic hydrocarbon, trioctyl phosphate and 2-ethyl anthraquinone, the volume ratio of the heavy aromatic hydrocarbon to the trioctyl phosphate is 75:25-80:20, the concentration of the heavy aromatic hydrocarbon is 660-680m L/L, the concentration of the trioctyl phosphate is 210-230m L/L, the concentration of the 2-ethyl anthraquinone is 110-130 g/L, the reaction temperature is 20-100 ℃, controlling the pressure in a supergravity rotating packed bed to be 0.1-10MPa in the reaction process, and enabling the obtained liquid phase reaction products and gas products to flow out through a through hole;

(3) collecting liquid phase reaction products, oxidizing and extracting the liquid phase reaction products to obtain hydrogen peroxide products; condensing the gas phase reaction product to obtain gas and liquid phase, exhausting the gas, and mixing the liquid phase with the liquid phase reaction product.

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