A method for treating reactor deactivation in an epoxide alkane reaction system and its application.

Abstract

This invention discloses a method for treating reactor deactivation in an alkylene oxide reaction system and its application. The alkylene oxide reaction system includes one or more reactors, and the system reacts with organic peroxides, olefins, and solvents as raw materials. The treatment method includes: (1) stopping the feeding of organic peroxides into the reactor; (2) optionally feeding olefins and optionally solvents into the reactor; and (3) feeding solvents into the reactor so that the materials therein flow into a recovery tank. According to this invention, after the feeding of organic peroxides into a reactor in the system is stopped, the residual organic peroxides in the reactor can be completely converted, ensuring the safety of the reaction system; at the same time, the raw material olefins in the reactor can be effectively recovered, saving material consumption.

Description

Technical Field

[0001] This invention relates to the field of epoxide alkane preparation, and particularly to a method for treating reactor deactivation in an epoxide alkane reaction system and its application. Background Technology

[0002] Epoxidized alkanes are important raw materials for organic chemical synthesis. Industrially, epoxidation reactions often use titanium-silicon catalysts. When the catalyst activity decreases or becomes deactivated, the reactor needs to be opened for catalyst replacement. Since the concentration of reactants gradually decreases along the reaction flow direction, the degree of catalyst deactivation is not uniform, especially in epoxidation reaction systems with multiple reactors, where the catalyst deactivation is highest in the logic-first reactor. When the catalyst in the logic-first reactor reaches the replacement threshold, the other reactors can still operate normally. Therefore, under normal operating conditions, it is necessary to separately shut down the reactor with deactivated catalyst, remove the feed, and replace the catalyst.

[0003] Chinese patent CN1325484C discloses an epoxidation system in a fixed-bed reactor, a method for producing ethylene oxide compounds by reacting olefins with hydroperoxide reactants in the presence of a solid epoxidation catalyst, wherein the olefins and hydroperoxide reactants are first reacted in at least two fixed-bed reactors containing fresh catalysts, the olefins being fed sequentially into the reactors, and the hydroperoxides being fed in parallel into the reactors, and then the reactor effluent from the last reactor is passed through at least one other reactor containing at least partially deactivated epoxidation catalysts.

[0004] Chinese patent CN1449392A discloses a method for producing epoxides using peroxides. In at least two reactors arranged in series, each containing a portion of a catalyst, epoxides are produced by reacting olefins and peroxides in the presence of a catalyst and a solvent. According to this method, peroxides are added only in the first reactor, and no fresh peroxides are added to the subsequent one or more reactors. Instead, peroxides present in the medium from the preceding reactors and not consumed in the preceding reactors are used.

[0005] However, existing technologies still suffer from high energy consumption and affect the entire epoxy process. Summary of the Invention

[0006] To overcome the problems existing in the prior art, this invention provides a method for treating reactor deactivation in an epoxide reaction system and its application. The epoxide reaction system uses organic peroxides and olefins as raw materials, reacting them in a catalyst-filled reactor to produce epoxides. When the catalyst in the reactor is deactivated, the feed of organic peroxides to the reactor is stopped, and olefins and optionally a solvent are supplied to the reactor to contact the catalyst. A protective gas is also supplied to the reactor. This effectively solves the problems of incomplete conversion of organic peroxides and olefin recovery in the reactor after the feed of organic peroxides in the epoxide reaction system is stopped, ensuring production safety while saving material consumption and reducing operating costs.

[0007] The first aspect of the present invention provides a method for treating reactor deactivation in an alkyl oxidant reaction system, the alkyl oxidant reaction system comprising one or more reactors, the alkyl oxidant reaction system using organic peroxides, olefins and solvents as raw materials for the reaction, wherein the treatment method comprises: (1) stopping the introduction of organic peroxides into the reactor, (2) optionally introducing olefins and optionally solvents into the reactor, and (3) introducing solvents into the reactor so that the materials therein flow into a recovery tank.

[0008] In step (2), the olefin is preferably the same as the olefin in the raw material, and in step (3), the solvent is preferably the same as the solvent in the raw material.

[0009] During step (1) and / or step (2) and / or step (3), a protective gas is introduced into the reactor; preferably, the protective gas is selected from at least one of nitrogen, carbon dioxide, and inert gas, and more preferably from at least one of helium, neon, argon, nitrogen, and carbon dioxide.

[0010] Before step (2), the concentration of organic peroxides at the reactor outlet is obtained; preferably, the concentration of organic peroxides in the liquid phase for olefin removal in the reactor is obtained as follows:

[0011]

[0012] In the formula: The mass concentration of organic peroxides that do not contain olefins at the reactor outlet; This represents the measured mass concentration of organic peroxides at the reactor outlet. This represents the olefin mass concentration at the reactor outlet.

[0013] When the concentration of organic peroxides in the liquid phase for olefin removal in the reactor is 0-1 wt%, step (2) is skipped, and step (3) is performed directly.

[0014] When the concentration of organic peroxides in the liquid phase for olefin removal in the reactor is greater than 1 wt%, step (2) includes: introducing olefins and optional solvents into the reactor; and simultaneously, obtaining the concentration of organic peroxides in the liquid phase for olefin removal in the reactor in real time, and stopping step (2) and proceeding to step (3) when the concentration changes from greater than 1 wt% to 0-1 wt%.

[0015] After step (3), the pressure of the reactor is released; preferably, the olefin content in the reactor is detected before releasing the pressure of the reactor, and the pressure of the reactor is released when the olefin content in the reactor is less than 5 wt%.

[0016] When a solvent is introduced into the reactor, the linear velocity of the solvent flow in the reactor is in the range of 0.0001 to 0.5 cm / s when the solvent comes into contact with the catalyst in the reactor.

[0017] When olefins are introduced into the reactor, the temperature of the reactor is controlled to be 10–200°C, preferably 40–130°C.

[0018] A second aspect of the present invention is to provide the application of the processing method described in the first aspect of the present invention in the preparation of epoxides.

[0019] A third aspect of the present invention provides a method for preparing epoxides, comprising: reacting raw materials including organic peroxides, olefins, and solvents in a system including at least one reactor to prepare epoxides, wherein each reactor is independently filled with a catalyst, and when the catalyst in one of the reactors is deactivated, the treatment method described in the first aspect of the present invention is used for treatment, while the other reactors normally receive and discharge materials.

[0020] The organic peroxide is selected from at least one of hydrogen peroxide, ethylbenzene hydrogen peroxide, cumene hydrogen peroxide, and tert-butylhydrogen peroxide; and / or, the olefin is selected from C2 to C10 olefins, preferably at least one of ethylene, propylene, and butene; and / or, the solvent is selected from organic solvents, preferably at least one of alcohol solvents, aromatic solvents, and water, more preferably at least one of methanol, isobutane, ethylbenzene, cumene, butadiene, and water.

[0021] In a preferred embodiment, under normal operating conditions, the molar ratio of olefins to organic peroxides in the feedstock is controlled to be 2 to 50.

[0022] Other conditions under normal operating conditions (such as temperature and pressure) can be obtained using existing technologies. For example, controlling the reactor outlet pressure above 5.5 MPa can prevent olefins (such as propylene) from vaporizing at the reaction temperature (since it is a series reaction system, the overall pressure drop of the reaction system gradually increases as the material flows, and the pressure at the reactor outlet is the lowest pressure point in the reaction system. Therefore, controlling the reactor outlet pressure can control the pressure of the entire reaction system to be above 5.5 MPa).

[0023] In a preferred embodiment, deactivation is determined based on the temperature rise inside the reactor.

[0024] In a further preferred embodiment, the reactor is determined to be inactive when the temperature rise inside the reactor is below 10°C. Preferably, the reactor is determined to be inactive when the temperature rise inside the reactor is below 10°C when the temperature inside the reactor is above 110°C.

[0025] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; 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. In the following, various technical solutions can, in principle, be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) According to the present invention, after the organic peroxide in a certain reactor in the system stops feeding, the organic peroxide remaining in the reactor can be completely converted, thus ensuring the safety of the reaction system.

[0028] (2) According to the present invention, after the organic peroxide in a certain reactor in the system stops feeding, the raw material olefin in the reactor can be effectively recovered, saving material consumption;

[0029] (3) According to the present invention, while ensuring production safety, material consumption is saved and operating costs are reduced. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the normal operating condition of the epoxidation system described in this invention. The thick solid line in the diagram represents material flow, and the thin dashed line represents no material flow in that pipeline.

[0031] Figure 1In the diagram, 1 represents an organic peroxide; 2 represents an olefin; 3 represents a solvent; 4 represents the epoxidation reaction product; V1 represents a propylene recovery tank; and R1, R2, and R3 represent epoxidation reactors filled with catalysts.

[0032] Figure 2 This is a schematic diagram of the R1 epoxidation reactor of the epoxidation system described in this invention, showing the stoppage of peroxide feed. In the diagram, organic peroxide solution 1 is directly fed into R2, while olefin 2 continues to be fed into R1. The concentration of organic peroxide at the outlet of R1 (reaction solution without propylene) is continuously monitored.

[0033] Figure 3 This is a schematic diagram of the epoxidation system R1 reactor of the present invention, in which both peroxide and olefin feed are stopped. In the diagram, organic peroxide solution 1 and olefin 2 are directly fed into R2, and solvent 3 is fed into R1 from the bottom of the reactor. The olefin in R1 is recovered to propylene recovery tank V1. Detailed Implementation

[0034] The features and advantages of the present invention will become clearer and more apparent from the following detailed description.

[0035] One of the objectives of this invention is to provide a method for treating reactor deactivation in an alkylene oxide reaction system, the alkylene oxide reaction system comprising one or more reactors, the alkylene oxide reaction system using organic peroxides, olefins and solvents as raw materials for the reaction, wherein the treatment method comprises: (1) stopping the introduction of organic peroxides into the reactor (referring to the reactor with deactivated catalyst), (2) optionally introducing olefins and optionally solvents into the reactor, and (3) introducing solvents into the reactor so that the materials therein flow into a recovery tank.

[0036] Specifically, when the reactor inlet temperature reaches 110℃ (as the operating cycle progresses, the activity of the epoxidation catalyst gradually decreases; the lower the activity, the higher the required reaction temperature), a temperature rise below 10℃ indicates deactivation and the need for catalyst replacement. The epoxidation reaction is exothermic; the higher the conversion rate, the greater the temperature rise. Under the same conditions, higher catalyst activity results in a higher conversion rate. When the reaction temperature has reached 110℃, a very low temperature rise indicates that the catalyst activity has fallen below a certain level, necessitating catalyst replacement.

[0037] In a preferred embodiment, a protective gas is introduced into the reactor during step (1) and / or step (2) and / or step (3).

[0038] In a further preferred embodiment, the protective gas is selected from at least one of nitrogen, carbon dioxide, and inert gases, preferably from at least one of helium, neon, argon, nitrogen, and carbon dioxide.

[0039] In a preferred embodiment, the concentration of organic peroxides at the reactor outlet is obtained before step (2).

[0040] When sampling and analyzing the concentration of organic peroxides at the reactor outlet, it is necessary to reduce the temperature and pressure. During this process, olefins will flash, resulting in a large change in the concentration of olefins in the liquid phase. Therefore, in this invention, the concentration of organic peroxides is calculated based on the liquid phase after deducting olefins.

[0041] In a further preferred embodiment, the concentration of organic peroxides in the liquid phase for olefin removal within the reactor is obtained as follows:

[0042]

[0043] In the formula: The mass concentration of organic peroxides that do not contain olefins at the reactor outlet; The measured value of the organic peroxide mass concentration at the reactor outlet (i.e., the measured value of the sample taken at the reactor outlet; after de-cooling and depressurization sampling, there will still be a certain concentration of olefins in the liquid phase); The above data represents the olefin concentration at the reactor outlet (after decooling and depressurization sampling at the reactor outlet, there will still be a certain concentration of propylene in the liquid phase; the above data represents the concentration of propylene in the liquid phase).

[0044] Among them, the concentration of organic peroxides at the outlet of the fixed-bed reactor was measured. Methods, including but not limited to iodine titration (iodometric method), near-infrared spectroscopy (NIR), or liquid chromatography (LC), for determining the olefin mass concentration at the reactor outlet. Liquid chromatography was used.

[0045] In a preferred embodiment, when the concentration of organic peroxides in the liquid phase for olefin removal in the reactor is 0-1 wt%, step (2) is skipped and step (3) is performed directly.

[0046] When the concentration of organic peroxides is between 0 and 1 wt%, the content is already very low. Introducing olefins into the reactor at this point would be a redundant process, wasting time and manpower and increasing material consumption. Therefore, solvent is directly introduced into the reactor so that the material flows into the recovery tank.

[0047] In a preferred embodiment, when the concentration of organic peroxides in the liquid phase for olefin removal in the reactor is greater than 1 wt%, step (2) includes: introducing olefins and optional solvents into the reactor; simultaneously, obtaining the concentration of organic peroxides in the liquid phase for olefin removal in the reactor in real time, and stopping step (2) and proceeding to step (3) when the concentration changes from greater than 1 wt% to 0-1 wt%.

[0048] When the concentration of organic peroxides is greater than 1 wt%, olefins and optionally a solvent need to be introduced to allow the organic peroxides to react fully. Therefore, preferably, the method of the present invention is used in deactivation reactors where the concentration of organic peroxides in the liquid phase for olefin removal is greater than 1 wt%.

[0049] In a preferred embodiment, the pressure of the reactor is released after step (3).

[0050] In a further preferred embodiment, the olefin content in the reactor is detected before releasing the pressure in the reactor, and the pressure in the reactor is released only when the olefin content in the reactor is below 5 wt%.

[0051] Protective gas is used before, after, or during depressurization.

[0052] In a preferred embodiment, the system includes one or more reactors, each containing a catalyst. Reactor deactivation in this invention refers to catalyst deactivation within the reactor.

[0053] In a further preferred embodiment, when the system includes multiple reactors, the multiple reactors are connected in parallel, in series, in series-parallel, or in parallel-series configurations.

[0054] In a further preferred embodiment, when the catalyst in one of the reactors is deactivated, the deactivated reactor is subjected to the operations described in (1) to (3) above, while the other reactors are fed and discharged normally.

[0055] In a preferred embodiment, the reaction is performed in a pure liquid phase.

[0056] In a further preferred embodiment, the reactor is a fixed-bed reactor.

[0057] In a preferred embodiment, when a solvent is introduced into the reactor, the linear velocity of the solvent flow in the reactor when the solvent contacts the catalyst is in the range of 0.0001 to 0.5 cm / s, for example, 0.0001 cm / s, 0.0005 cm / s, 0.001 cm / s, 0.005 cm / s, 0.01 cm / s, 0.05 cm / s, 0.1 cm / s, 0.2 cm / s, 0.3 cm / s, 0.4 cm / s, or 0.5 cm / s.

[0058] Through extensive experimentation, the inventors discovered that when the solvent linear velocity exceeds 0.5 cm / s, it can damage the catalyst bed. For example, if the linear velocity is greater than the catalyst settling velocity, the catalyst will be entrained, and the bed morphology will be disrupted. When the solvent linear velocity is below 0.0001 cm / s, it will result in an excessively long solvent purging time.

[0059] In a preferred embodiment, when olefins are introduced into the reactor, the temperature of the reactor is controlled to be 10–200°C, preferably 40–130°C, for example 10°C, 30°C, 50°C, 80°C, 100°C, 120°C, 150°C, 180°C or 200°C.

[0060] A second objective of this invention is to provide the application of the processing method described in one objective of this invention in the preparation of epoxides.

[0061] A third objective of this invention is to provide a method for preparing epoxides, comprising: reacting raw materials including organic peroxides, olefins, and solvents in a system including at least one reactor to prepare epoxides, wherein each reactor is independently filled with a catalyst, and when the catalyst in one reactor is deactivated, the treatment method described in one objective of this invention is used for treatment, while the other reactors normally receive and discharge materials.

[0062] In a preferred embodiment, the organic peroxide is selected from at least one of hydrogen peroxide, ethylbenzene hydrogen peroxide, cumene hydrogen peroxide, and tert-butylhydrogen peroxide.

[0063] In a preferred embodiment, the olefin is selected from C2 to C10 olefins, preferably at least one of ethylene, propylene, and butene.

[0064] In a preferred embodiment, the solvent is selected from organic solvents, preferably from at least one of alcohol solvents, aromatic solvents, and water, and more preferably from one or at least one of methanol, isobutane, ethylbenzene, cumene, butylbenzene, and water.

[0065] In a preferred embodiment, under normal operating conditions, the molar ratio of olefins to organic peroxides in the feedstock is controlled to be 2 to 50, for example, 2, 5, 10, 20, 30, 40 or 50.

[0066] In a preferred embodiment, the catalyst is selected from any catalyst disclosed in the prior art that can be used to prepare epoxides from organic peroxides and olefins, preferably but not limited to titanium-containing catalysts, such as titanium silicate molecular sieves and / or titanium dioxide.

[0067] Example

[0068] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0069] It should also be noted that the various specific technical features described in the following embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the various possible combinations will not be described separately in this invention.

[0070] Furthermore, various embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention. The resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0071] Unless otherwise specified, the raw materials used in the examples and comparative examples are all disclosed in the prior art, such as those that can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0072] The reactor was filled with a catalyst prepared according to patent CN104437618B, "Catalyst, Preparation Method and Application for Propylene to Propylene Oxide": 280g of n-hexadecylamine was slowly added to a mixed solution of 2500g deionized water and 1300g ethanol under stirring at 45℃ to form a transparent solution A; 36g of tridecafluorooctyltrimethoxysilane and 30g of tetrabutyl titanate were simultaneously added to a mixed solution of 240g isopropanol and 480g tetraethyl orthosilicate, and stirred for 60min to form solution B; solution B was slowly added to solution A, stirred for 24h, filtered, washed, dried at 120℃ for 12h, and then refluxed in a solution of ethanol and a small amount of hydrochloric acid aqueous solution (0.2mol) for 2h to remove residual template agent, filtered, washed, and filtered again, repeated three times. The filtered product was dried at 120℃ for 24h and heated at 200℃ for 6h under a nitrogen atmosphere to obtain a white solid powder. The reaction mixture had the following molar ratios: Ti / Si = 0.0370, n-hexadecylamine / Si = 0.4873, water / Si = 58.2488, water / alcohol = 4.3056, and tridecafluorooctyltrimethoxysilane / tetraethyl orthosilicate = 0.0333. 100g of the powdered sample prepared above was added to a 250ml cumene bath containing 40g of hexamethyldisilazane. Under rapid stirring and reflux, the temperature was raised to 150℃ and reacted at this temperature for 4 hours. Then, the residual hexamethyldisilazane and cumene solvent were evaporated under vacuum at this temperature, yielding a porous silica catalyst with highly dispersed active components and highly hydrophobic and partially oleophobic properties.

[0073]

Example 1

[0074] Taking a 300,000-ton / year cumene hydrogen peroxide epoxidation system to propylene oxide as an example, the system includes three reactors connected in series, each filled with a catalyst, which is the aforementioned titanium-silicon catalyst.

[0075] In this embodiment, solvent 3 is cumene, olefin is propylene, and organic peroxide is cumene hydrogen peroxide.

[0076] like Figure 1 As shown, under normal operating conditions, 185.8 t / h of cumene hydrogen peroxide 1 and propylene 2 are mixed and fed into the epoxidation reaction system, where the molar ratio of propylene to cumene hydrogen peroxide is 8. The epoxidation reaction system is equipped with three reactors, and the reactor outlet pressure is controlled above 5.5 MPa. The reaction mixture passes through reactors R1, R2 and R3 in sequence, and finally obtains a liquid phase composition containing propylene oxide products. Subsequent components enter the distillation system for separation.

[0077] like Figure 2 As shown, when the catalyst in reactor R1 reaches the catalyst replacement condition, that is, when the inlet temperature reaches 110℃, the temperature rise of reactor R1 is less than 10℃. The feeding of cumene peroxide into reactor R1 is stopped. Since there is still unreacted cumene peroxide in reactor R1 (and the concentration of cumene peroxide in the propylene-free reaction solution is 30wt%), propylene is continued to be fed into R1 until the concentration of cumene peroxide at the outlet of reactor R1 (in the propylene-free reaction solution) is less than 1wt% (then the propylene feeding is stopped; the temperature during the entire propylene feeding process is controlled within 40–130℃).

[0078] like Figure 3 As shown, propylene feeding into reactor R1 is stopped, and it is directly mixed with cumene hydrogen peroxide and then introduced into reactor R2. Since R1 contains a large amount of propylene, cumene solvent is introduced from the bottom of reactor R1 (the linear velocity of the cumene flow within the reactor is controlled within the range of 0.0001–0.5 cm / s) to recover the propylene in reactor R1 to the propylene recovery tank V1. When the propylene content in the reactor is below 5 wt%, reactor R1 is depressurized. Subsequent reactor R1 undergoes solvent discharge recovery, purging, displacement, and solvent replacement operations as needed.

[0079]

Example 2

[0080] Under the same process operating conditions as in Example 1, the difference is that when the catalyst in reactor R3 reaches the catalyst replacement condition, the concentration of cumene hydrogen peroxide in the propylene-free reaction liquid at the reactor outlet is measured to be 0.8 wt%. At this point, reactor R3 is isolated from other reactors, and cumene solvent is directly introduced from the bottom of reactor R3 (the linear velocity of the cumene flow in the reactor is controlled within the range of 0.0001 to 0.5 cm / s). Propylene and cumene in reactor R1 are recovered to propylene recovery tank V1. When the propylene content in the reactor is lower than 5 wt%, reactor R3 is depressurized. Subsequently, reactor R3 undergoes solvent discharge recovery, purging, displacement, and catalyst replacement operations as needed.

[0081]

Example 3

[0082] The process operating conditions are the same as in Example 1, except that when the catalyst in reactor R2 reaches the catalyst replacement condition, the concentration of cumene hydrogen peroxide in the propylene-free reaction solution at the reactor outlet is measured to be 10 wt%. Propylene 2 continues to be introduced into R2 until the concentration of cumene hydrogen peroxide (in the propylene-free reaction solution) at the reactor R2 outlet is below 1 wt% (then the propylene introduction is stopped). Reactor R2 is isolated from other reactors, and solvent cumene is introduced from the bottom of reactor R2 (the linear velocity of the cumene flow in the reactor is controlled within the range of 0.0001 to 0.5 cm / s). The propylene in reactor R2 is recovered to the propylene recovery tank V1. When the propylene content in the reactor is below 5 wt%, reactor R2 is depressurized. Subsequently, reactor R2 undergoes solvent discharge recovery, purging, displacement, and catalyst replacement operations as needed.

[0083] Comparative Example 1

[0084] Repeat the process in Example 1, except that, as Figure 2 As shown, when the feed of cumene hydrogen peroxide 1 to reactor R1 stops, the feed of propylene 2 into R1 also stops, meaning that both cumene hydrogen peroxide 1 and propylene 2 are simultaneously bypassed to reactor R2. Since reactor R1 contains a large amount of incompletely converted cumene hydrogen peroxide, directly replacing it with solvent cumene will result in the loss of cumene hydrogen peroxide in reactor R1, increasing reactant consumption. Furthermore, the process of replacing the cumene hydrogen peroxide with solvent in the return tank V1 can easily lead to thermal decomposition of the cumene hydrogen peroxide, resulting in temperature runaway.

[0085] Comparative Example 2

[0086] Repeat the process in Example 1, except that, as Figure 3As shown, reactor R1 contains a large amount of propylene. Solvent cumene is introduced from the bottom of reactor R1 to recover the propylene from reactor R1 to propylene recovery tank V1. When reactor R1 is depressurized, the propylene content is 10 wt%. During the depressurization process, reactor R1 cools down, leading to a decrease in the temperature of the entire system. This can even cause the byproduct water generated within the system to freeze, severely impacting the overall production efficiency of the system. The possible reason is that due to the high propylene content in reactor R1, the propylene may vaporize during the depressurization process, causing a decrease in the temperature of reactor R1 and the entire system.

[0087] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A method for treating reactor deactivation in an alkylene oxide reaction system, wherein the alkylene oxide reaction system comprises multiple reactors, and the alkylene oxide reaction system uses organic peroxides, olefins, and solvents as raw materials for the reaction, wherein... The treatment method includes: (1) stopping the introduction of organic peroxides into the reactor; (2) optionally introducing olefins and optionally a solvent into the reactor; and (3) introducing a solvent into the reactor so that the material therein flows into a recovery tank. The concentration of organic peroxides at the reactor outlet is obtained before step (2). The concentration of organic peroxides in the liquid phase of the reactor used for olefin removal is obtained as follows: In the formula: The mass concentration of organic peroxides that do not contain olefins at the reactor outlet; This represents the measured mass concentration of organic peroxides at the reactor outlet. The olefin mass concentration at the reactor outlet; When the concentration of organic peroxides in the liquid phase for olefin removal in the reactor is 0~1wt%, step (2) is skipped and step (3) is performed directly. When the concentration of organic peroxides in the liquid phase for olefin removal in the reactor is greater than 1 wt%, step (2) includes: introducing olefins and optional solvents into the reactor; and simultaneously, obtaining the concentration of organic peroxides in the liquid phase for olefin removal in the reactor in real time, and stopping step (2) and proceeding to step (3) when the concentration changes from greater than 1 wt% to 0~1 wt%.

2. The processing method according to claim 1, characterized in that, During step (1) and / or step (2) and / or step (3), a protective gas is introduced into the reactor.

3. The processing method according to claim 2, characterized in that, The protective gas is selected from at least one of helium, neon, argon, nitrogen, and carbon dioxide.

4. The processing method according to claim 1, characterized in that, After step (3), the pressure in the reactor is released.

5. The processing method according to claim 4, characterized in that, Before releasing the pressure in the reactor, the olefin content in the reactor is detected, and the pressure in the reactor is released only when the olefin content in the reactor is below 5 wt%.

6. The processing method according to any one of claims 1 to 5, characterized in that, When a solvent is introduced into the reactor, the linear velocity of the solvent flow in the reactor is in the range of 0.0001~0.5cm / s when the solvent comes into contact with the catalyst in the reactor.

7. The processing method according to claim 6, characterized in that, When olefins are introduced into the reactor, the temperature of the reactor is controlled to be 10~200℃.

8. The processing method according to claim 6, characterized in that, When olefins are introduced into the reactor, the temperature of the reactor is controlled to be 40~130℃.

9. The application of the processing method according to any one of claims 1 to 8 in the preparation of epoxides.

10. A method for preparing epoxides, comprising: Raw materials, including organic peroxides, olefins, and solvents, are reacted in a system comprising at least one reactor to prepare epoxides, wherein each reactor is independently packed with a catalyst, and when the catalyst in one reactor is deactivated, it is treated by the treatment method described in any one of claims 1 to 8, while the other reactors normally feed and discharge materials.

11. The preparation method according to claim 10, characterized in that, The organic peroxide is selected from at least one of ethylbenzene hydroperoxide, cumene hydroperoxide, and tert-butyl hydroperoxide; and / or The olefin is selected from C2-C10 olefins; and / or, The solvent is selected from organic solvents.

12. The preparation method according to claim 10, characterized in that, The olefin is selected from at least one of ethylene, propylene, and butene; and / or, The solvent is selected from at least one of alcohol solvents and aromatic solvents.

13. The preparation method according to claim 10, characterized in that, The solvent is selected from one or more of methanol, ethylbenzene, cumene, and butylbenzene.

14. The preparation method according to any one of claims 10 to 13, characterized in that, The molar ratio of olefins to organic peroxides in the raw materials is controlled to be 2-50.

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