A reaction device, production system and method for preparing MIBK

Abstract

The present application relates to the technical field of one-step preparation of MIBK from acetone, and particularly relates to a reaction device, a production system and a method for preparing MIBK. The reaction device comprises a reactor, a steam pocket, a heat removal medium source and a cold-heat exchange device. The reactor is a shell-and-tube reactor, and the reactor comprises a heat removal medium inlet and a heat removal medium outlet which are connected with a shell pass of the reactor. The heat removal medium inlet is located at a lower part of the reactor, and the heat removal medium outlet is located at an upper part of the reactor. The steam pocket is connected with the heat removal medium source through a pipeline. The steam pocket further comprises a liquid phase outlet and a vapor phase inlet. The liquid phase outlet is connected with the heat removal medium inlet of the reactor through a pipeline, and the vapor phase inlet is connected with the heat removal medium outlet of the reactor through a pipeline. The steam pocket is further connected with the cold-heat exchange device through a pipeline and forms a closed loop circulation. The present application breaks through the design bottleneck that the existing MIBK device cannot be further expanded, and can realize the expansion of the production scale of the MIBK reaction device by using a single reactor. Furthermore, the heat removal of the reaction device of the present application is more stable, and unexpected technical effects are achieved.

Description

Technical Field

[0001] This invention relates to the field of one-step acetone preparation of MIBK, and particularly to a reaction apparatus, production system and method for preparing MIBK. Background Technology

[0002] Methyl isobutyl ketone (MIBK) is an excellent medium-boiling-point solvent with stable chemical properties. It can meet the special requirements of high-grade coatings in terms of solid composition, evaporation rate, leveling properties, coating strength, and appearance. Due to its good solubility, excellent miscibility with other solvents, and suitable boiling point, MIBK has become a major auxiliary solvent for high-grade coatings.

[0003] Currently, the mainstream technology for MIBK production is the one-step acetone process. This process offers advantages such as a short process flow, low investment, high acetone conversion rate, high MIBK selectivity, and low raw material and energy consumption. Acetone and hydrogen react in a fixed-bed reactor under the action of a catalyst to produce MIBK. The condensation, dehydration, and hydrogenation reactions occur simultaneously, and the reaction equations are as follows:

[0004] 2CH3COCH3+H2-----CH3(CH3)CHCH2COCH3+H2O

[0005] The main components of the acetone and hydrogen synthesis MIBK reaction system are: acetone (boiling point 56℃ at normal pressure), MIBK (boiling point 116℃ at normal pressure), and hydrogen. Theoretically, the hydrogenation of acetone is a strongly exothermic reaction with a heat of reaction of 146 kJ / mol. A resin catalyst is used for MIBK preparation. Resin catalysts are easily deactivated at 140℃, leading to reduced conversion rate and equipment corrosion. Therefore, heat removal is crucial. During the reaction, the heat must be removed promptly to avoid hot spots. In the initial stage of the reaction, the temperature needs to be controlled at 90-95℃; in the steady-state stage, the temperature needs to be controlled at 95-100℃; and in the final stage, the temperature needs to be controlled at 120-130℃.

[0006] For a long time, the largest MIBK plant in the Chinese market has only reached a capacity of 15,000 tons, without scaling up from a single reactor. Reactor capacity has always been a design bottleneck. To increase MIBK capacity to 20,000 tons or more, multiple reactors must be connected in parallel to scale up the plant, resulting in increased equipment investment and high operating costs.

[0007] Therefore, how to overcome the design bottleneck that existing MIBK devices cannot be further scaled up has been a goal that the field has been trying to achieve. Summary of the Invention

[0008] The inventors of this invention, through research, believe that the limiting factor for reactor processing capacity lies in the challenge of heat removal, preventing further scaling up of the MIBK single reactor. Effectively controlling the reaction temperature, promptly removing reaction heat, and avoiding the generation of hot spots in the reactor have always been design bottlenecks. Poor heat removal leads to catalyst deactivation, affecting reaction conversion rates. Currently, the conventional heat removal method is hot water heat removal, absorbing reaction heat through the increase in water temperature. This simple method of heat absorption by water temperature change results in slow flow velocity of hot water in the reactor shell side, uneven flow field, low heat transfer coefficient, and poor heat transfer effect. To meet the heat removal requirements, reactors using water heat removal are typically long and slender with a large length-to-diameter ratio, generally 2.6m in diameter and 6m in length, with an length-to-diameter ratio of 2.31. It is impossible to further increase the reactor diameter to reduce the length-to-diameter ratio and achieve stable heat removal using water. This challenge prevents further scaling up of the MIBK single reactor.

[0009] Furthermore, existing technologies not only suffer from the limitation of scaling up the single-reactor scale of the MIBK reactor, but also from unstable heat removal: 1) Due to the use of water for heat removal, the reaction temperature is 90-95℃ in the initial stage of the reaction, while the atmospheric boiling point of hot water is 100℃. Therefore, the latent heat of water cannot be utilized for heat removal; only sensible heat can be used. The hot water is unevenly distributed in the shell side of the reactor, with a low flow rate, resulting in a low heat transfer coefficient and affecting heat exchange efficiency. 2) Simultaneously, to make the reaction more uniform and controllable, the temperature difference between the hot water inlet and outlet in the shell side needs to be minimized. A smaller temperature difference results in a larger hot water circulation volume. For economic reasons, a temperature difference of 5℃ is typically used. In this situation, if the hot water enters from the bottom and exits from the top, the most vigorous reaction occurs at the reactor inlet, where the hot water temperature for heat removal is highest, affecting heat exchange. If the hot water enters from the top and exits from the bottom, the inlet of the reaction tube requires preheating, resulting in poor preheating and affecting reaction activation. Improper heat removal during these processes can easily create reaction hotspots, causing catalyst deactivation and plant shutdown.

[0010] In summary, under current technological conditions, MIBK reaction devices cannot be further scaled up, and the unstable heat removal during the MIBK reaction has always been a bottleneck that needs to be overcome in this field. Through research, the inventors of this invention unexpectedly discovered that the device of this invention can overcome the limitation of existing MIBK reaction devices in terms of scale-up. The reactor of this invention is no longer limited to the slender, high aspect ratio design of existing MIBK reactors (i.e., diameter 2.6m, height 6m). Using the heat removal device of this invention, and employing an organic reagent with a boiling point of 50-80℃ as the heat removal medium, such as acetone, the reactor diameter can be increased to over 9m, and the aspect ratio can be reduced to 0.67. The increased reactor diameter and reduced aspect ratio allow for the scaling up of MIBK reaction device production using a single reactor. Furthermore, the heat removal of the reaction device of this invention is more stable, achieving unexpected technical effects.

[0011] The first aspect of the present invention is to provide a reaction apparatus for preparing MIBK, comprising a reactor, a steam drum, a heat removal medium source, and a heat exchange device;

[0012] The reactor is a shell-and-tube reactor, which includes a reactant inlet and a product outlet connected to the tube side of the reactor. The reactor also includes a heat-removing medium inlet and a heat-removing medium outlet connected to the shell side of the reactor. The heat-removing medium inlet is located at the lower part of the reactor, and the heat-removing medium outlet is located at the upper part of the reactor.

[0013] The steam drum is connected to the heat removal medium source via a pipeline; the steam drum also includes a liquid phase outlet and a vapor phase inlet, the liquid phase outlet is connected to the heat removal medium inlet of the reactor via a pipeline, and the vapor phase inlet is connected to the heat removal medium outlet of the reactor via a pipeline.

[0014] The steam drum is also connected to the heat exchange equipment via pipelines to form a closed-loop circulation.

[0015] According to some preferred embodiments of the present invention, the reaction raw material inlet is connected to a hydrogen source and an acetone source.

[0016] According to some preferred embodiments of the present invention, the heat-relief medium is an organic reagent with a boiling point of 50-80°C.

[0017] The reason for this technological breakthrough lies in the fact that this invention uses a heat-removing medium, preferably an organic reagent with a boiling point of 50-80℃. This utilizes the latent heat of vaporization of the heat-removing medium (such as acetone) instead of hot water for heat removal. Since the reactor shell side is a two-phase system (gas and liquid), the vaporized heat-removing medium has no dead zones in the shell side, avoiding the slow flow velocity and uneven distribution issues associated with water heat removal due to baffles. This results in uniform temperature throughout the shell side, ensuring a consistent temperature from top to bottom on the low-temperature side. The heat transfer temperature difference is constant, the heat transfer coefficient is high, and the heat removal effect is better and more stable. This allows for the scaling up of MIBK reactor production using a single reactor, solving the long-standing bottleneck problem of not being able to scale up MIBK reactor production using a single reactor, achieving unexpected technological benefits.

[0018] Furthermore, in the reaction apparatus for preparing MIBK using this invention, the heat removal medium enters the reactor shell side from the bottom and exits from the top. During this process, the heat removal medium absorbs the heat of reaction. As the temperature rises, the heat removal medium thermally expands, the hot fluid rises, and the cold fluid replaces the hotter fluid in the circulation loop. This thermal expansion creates a density gradient between the reactor shell side inlet (heat removal medium inlet) and the reactor shell side outlet (heat removal medium outlet). This density difference causes the condensate in the steam drum to be continuously siphoned into the reactor shell side, and the heated and vaporized gas-liquid mixture automatically returns to the steam drum, forming a natural circulation. In this invention, the heat removal medium enters the shell side in a liquid state and then vaporizes for heat removal. This allows for heat removal via thermosiphon, eliminating the need for a circulating pump to drive the feed, resulting in lower energy consumption. Moreover, the vaporized heat removal medium, after flowing out of the shell side, can be used as a heat source for other devices, such as the reboiler in the separation unit, thus utilizing the heat. During this process, the vaporized heat removal medium is cooled after heat exchange, returns to the liquid phase, and is recycled as the heat removal medium for the shell side. In this way, compared to water-based heat removal, it can save a heat exchanger and a pump, reducing equipment investment and floor space, while also reducing energy consumption.

[0019] According to some preferred embodiments of the present invention, the heat removal medium is selected from at least one of acetone, methanol, ethanol, and tetrahydrofuran; preferably acetone. Using acetone for heat removal (boiling point 56°C at atmospheric pressure), utilizing the latent heat of vaporization of acetone, the liquid phase of acetone in the shell side of the reactor absorbs heat and vaporizes into a gas phase (temperature adjustable from 85-130°C), achieving a constant shell-side temperature, high heat transfer coefficient, good heat exchange effect, and avoiding reactor overheating. Enlarging the reactor size does not affect the heat removal effect, allowing for a scale-up of the equipment. Since acetone is the process medium, there is no need to consider reactor shell-side leakage, and no pollution issues exist. The vaporized acetone can be used as a heat source for the reboiler in the separation unit, thus utilizing the heat.

[0020] According to some preferred embodiments of the present invention, the steam drum is a horizontal container.

[0021] According to some preferred embodiments of the present invention, the bottom of the steam drum is higher than the top of the reactor; preferably, the height difference between the bottom of the steam drum and the top of the reactor is 1-20m, which is more conducive to the heat dissipation medium and the density difference to generate a better siphon effect.

[0022] According to some preferred embodiments of the present invention, the steam drum includes a heat exchange outlet and a heat exchange inlet connected to the heat exchange equipment. The heat exchange outlet is located at the top of the steam drum, and / or the heat exchange inlet is located on the side wall of the steam drum. In this way, the vapor-phase heat removal medium flows out from the top without interfering with the heat removal medium going to the shell side of the reactor, while also carrying more heat. The location of the heat exchange inlet on the side wall of the steam drum allows the cooled heat removal medium to serve as feedstock for the heat removal medium going to the shell side of the reactor with reduced heat exchange.

[0023] According to some preferred embodiments of the present invention, a heat-removing medium reflux pump is provided in the closed-loop circulation path connecting the steam drum and the heat exchange equipment; preferably, the heat-removing medium reflux pump is provided in the passage connecting the heat exchange equipment and the heat exchange inlet of the steam drum.

[0024] According to some preferred embodiments of the present invention, the inlet of the heat removal medium of the reactor includes a plurality of feed holes distributed circumferentially along the reactor; the liquid phase outlet of the steam drum includes a plurality of liquid outlets disposed at the bottom or lower side wall of the steam drum, each of the liquid outlets being connected to the feed holes of the reactor via pipelines.

[0025] As mentioned above, the heat dissipation medium inlet is located at the lower part of the reactor, which is a shell-and-tube reactor. That is, the heat dissipation medium inlet is provided on the side wall of the lower part of the shell-and-tube reactor. Preferably, multiple feed holes are evenly distributed around the lower side wall of the shell-and-tube reactor, that is, multiple feed holes are preferably evenly distributed around the circumference of the reactor.

[0026] According to the present invention, preferably, the liquid phase of the heat removal medium is drawn out from the bottom of the steam drum, the vapor phase of the heat removal medium is introduced from the top of the steam drum, and the heat removal medium vaporized after absorbing the heat of reaction is collected from the top of the steam drum and sent to a heat exchanger. In the heat exchanger, it condenses into a liquid phase and is then returned to the steam drum. The liquid phase inside the steam drum is drawn out from the bottom of the steam drum and sent to the reactor for heat absorption. Preferably, the liquid phases of the heat removal medium entering the reactor are each connected to the heat removal medium inlet of a separate reactor.

[0027] More preferably, the number of feed holes is 2-20, more preferably 2-4; and / or, the plurality of feed holes are uniformly distributed along the circumference of the reactor. This makes the cooling medium entering the shell side more uniform.

[0028] According to some preferred embodiments of the present invention, the heat removal medium outlet of the reactor includes a plurality of discharge holes preferably evenly distributed along the circumference of the reactor (i.e., a plurality of discharge holes preferably evenly distributed around the upper sidewall of the shell-and-tube reactor); the vapor phase inlet of the steam drum includes a plurality of steam feed inlets disposed at the top of the steam drum; each of the vapor phase inlets is connected to the discharge hole of the reactor via a pipeline; more preferably, the reaction apparatus further includes: a plurality of vapor phase pipelines each connected to the discharge hole of the reactor, and a plurality of collecting pipelines each connected to the steam feed inlet of the steam drum, the collecting pipelines being connected to at least one vapor phase pipeline to collect the material of at least one vapor phase pipeline in the collecting pipeline. Multiple heat removal medium vapor phase outlets enable a more uniform flow path of the heat removal medium within the reactor, resulting in better heat removal effect. The vapor phase pipelines are converged into a main pipe supplying the steam drum, effectively reducing the connecting pipelines between the reactor and the steam drum, which is more advantageous in terms of pipeline layout, pipeline support, and construction workload.

[0029] More preferably, the vapor phase pipeline extends upward from the discharge port, with the height of the extended pipe opening being flush with the height of the reactor. Most preferably, multiple vapor phase pipelines are evenly distributed circumferentially at the top of the reactor. This results in a more uniform flow of the heat-removing medium within the reactor, leading to better heat removal performance.

[0030] More preferably, 2-4 vapor phase pipelines are connected to the same manifold pipeline.

[0031] More preferably, the number of discharge holes is 4-20, more preferably 6-8; and / or, the plurality of discharge holes are evenly distributed along the circumference of the reactor. This results in a more uniform flow of the heat-removing medium within the reactor, leading to better heat removal performance.

[0032] The gas feed inlets are evenly distributed on the top of the gas drum; and / or, the number of gas feed inlets is 2-6.

[0033] As mentioned above, the reactor of the present invention is no longer limited to the slender, high aspect ratio form of existing MIBK reactors. The reactor of the present invention can be either of a high or low aspect ratio. According to some preferred embodiments of the present invention, the aspect ratio of the reactor is 0.2-5, preferably 0.5-3; more preferably, with a fixed reactor height (i.e., length), the reactor of the present invention has a smaller aspect ratio, more preferably 0.5-2.5; even more preferably, the aspect ratio of the reactor is 0.5-1.5, and most preferably 0.5-1. For example, when the height of the reactor is 6m, the reactor diameter can be 9m. As mentioned above, the reactor of the present invention is larger in scale, breaking through the bottleneck of the previous inability to expand the scale.

[0034] According to some preferred embodiments of the present invention, the reactor is a tubular reactor.

[0035] According to some preferred embodiments of the present invention, the reactor tubes are packed with a catalyst, which is an existing catalyst suitable for the one-step production of MIBK from acetone, and the present invention is not particularly limited thereto. For example, the catalyst used in CN112745207A and CN110105183A may be used.

[0036] According to some preferred embodiments of the present invention, the heat exchange device is a device that needs to absorb heat, preferably at least one of a heat exchanger and a reboiler.

[0037] According to some preferred embodiments of the present invention, the shell side of the reactor is provided with baffles. Preferably, the baffles are a combination of one or more of baffle rods and perforated plates, which makes the flow field of the shell-side fluid uniform and facilitates the heat absorption phase change of the heat-removing medium. The baffle rods and perforated plates can be arranged in the prior art, and the present invention is not particularly limited thereto.

[0038] According to some preferred embodiments of the present invention, the heat-relief medium source can optionally provide a preheated heat-relief medium; preferably, the heat-relief medium source can optionally provide the preheated heat-relief medium through heat exchange with a steam network. Thus, at the initial stage of the reaction, the preheated heat-relief medium from the heat-relief medium source can be introduced into the shell side of the reactor, allowing the catalyst in the tube side of the reactor to activate more rapidly. The steam network is conventional equipment in chemical production and will not be described in detail here.

[0039] A second aspect of the present invention is to provide a production system for preparing MIBK, comprising the reaction apparatus for preparing MIBK described in the first aspect, preferably,

[0040] The MIBK production system also includes a preheater, a condenser, a gas-liquid separator, and a separation unit;

[0041] Preheaters are installed in the passages connecting the hydrogen source, the acetone source and the reaction raw material inlet of the reactor.

[0042] The reactor's reaction product outlet is sequentially connected to the condenser, gas-liquid separator, and separation unit.

[0043] According to some preferred embodiments of the present invention, the gas outlet of the gas-liquid separator is connected to the reaction feed inlet of the reactor and the hydrogen source via a pipeline, and the liquid outlet of the gas-liquid separator is connected to the feed inlet of the separation unit.

[0044] According to some preferred embodiments of the present invention, the separation unit includes a plurality of distillation columns connected in series. Preferably, the number of distillation columns is four, named according to the flow direction of the bottom material of each distillation column and the distillate at the top of the column, including a 2-methylpentane distillation column, an acetone distillation column, a water-isopropanol distillation column, and a methyl isobutyl ketone distillation column connected in sequence.

[0045] According to some preferred embodiments of the present invention, a reboiler is provided below the 2-methylpentane distillation column, and the heat exchange outlet of the steam drum is connected to the heat exchange inlet of the steam drum through the reboiler to form a closed loop. At the end of the reaction, as the reaction temperature increases, the temperature of the cooling medium also increases, and it can also be used as the heating medium for the bottom of the acetone column.

[0046] According to some preferred embodiments of the present invention, the passage connecting the top outlet of the acetone distillation column to the acetone source and the inlet of the reactor is connected by a pipeline.

[0047] According to some preferred embodiments of the present invention, an oil-water separator is provided on the pipeline between the water-isopropanol distillation column and the methyl isobutyl ketone distillation column, with the water outlet of the oil-water separator connected to the outside. The oil phase outlet of the oil-water separator is connected to the methyl isobutyl ketone distillation column.

[0048] A third aspect of the present invention is to provide a method for controlling the temperature conditions for preparing MIBK using the reaction apparatus for preparing MIBK described in the first aspect, comprising:

[0049] In the initial stage of the reaction, the heat-removing medium from the heat-removing medium source is preheated and then introduced into the shell side of the reactor to activate the catalyst in the tube side of the reactor. After that, the reaction raw materials are added to the tube side of the reactor to start the acetone hydrogenation reaction.

[0050] After the reaction begins, a liquid-phase heat-removing medium is introduced into the shell side of the reactor. The liquid-phase heat-removing medium vaporizes in the shell side of the reactor, removing part of the heat from the acetone hydrogenation reaction, so that the temperature of the tube side of the reactor is maintained within the target temperature range. Preferably, the temperature of the heat-removing medium in the shell side is 3-5°C lower than the target temperature of the tube side of the reactor.

[0051] The vaporized heat-removing medium obtained by vaporization in the shell side of the reactor rises to the steam drum, is then cooled by a heat exchanger, and returns to the steam drum as a liquid heat-removing medium. The liquid heat-removing medium then enters the shell side of the reactor for heat removal, and the cycle continues.

[0052] According to some preferred embodiments of the present invention, the liquid phase heat removal medium in the steam drum is siphoned into the shell side of the reactor.

[0053] According to some preferred embodiments of the present invention, in the initial stage of the reaction, the temperature of the preheated cooling medium is 85-88°C.

[0054] A fourth aspect of the present invention is to provide a method for preparing MIBK using the production system described in the second aspect:

[0055] Hydrogen and acetone, preheated by a preheater, are introduced into the tube side of the reactor. The acetone and hydrogen are then contacted with a catalyst for a hydrogenation reaction, yielding a reaction product containing MIBK. This MIBK-containing reaction product is then cooled by a condenser, and a gas-liquid separator is used to separate the gaseous and liquid phases. Optionally, the gaseous phase separated by the gas-liquid separator is returned to the tube side of the reactor, and the liquid phase separated by the gas-liquid separator is further separated by a separation unit to obtain the target MIBK product. Preferably,

[0056] The conditions for the hydrogenation reaction include controlling the temperature for preparing MIBK using the method described in the third aspect.

[0057] According to the present invention, the process and process parameters of "passing hydrogen and acetone preheated by a preheater into the tube side of the reactor, contacting the acetone and hydrogen with the catalyst to carry out a hydrogenation reaction to obtain a reaction product containing MIBK" are prior art. The one-step synthesis of MIBK from acetone can be referred to as an example, such as CN112745207A and CN110105183A.

[0058] In this invention, the process and equipment used in "cooling the reaction product containing MIBK in a condenser, separating the gaseous and liquid phases using a gas-liquid separator, returning the gaseous phase separated by the gas-liquid separator to the tube side of the reactor, and separating the liquid phase separated by the gas-liquid separator through multiple series-connected distillation columns to obtain the target MIBK product" can refer to existing technologies, such as the separation methods mentioned in CN00110591.4 and CN102050713 A.

[0059] According to some preferred embodiments of the present invention, the separation unit includes multiple distillation columns connected in series, more preferably four distillation columns connected in sequence as follows: a 2-methylpentane distillation column, an acetone distillation column, a water-isopropanol distillation column, and a methyl isobutyl ketone distillation column; through the distillation separation of the four distillation columns, 2-methylpentane, acetone, a mixture of water and isopropanol, and methyl isobutyl ketone are obtained sequentially; most preferably, the acetone obtained from the distillation separation is returned to the tube side of the reactor. Thus, the feedstock hydrogen and acetone are preheated, and then the reaction is carried out in a fixed-bed reactor. The reaction products and circulating gas are condensed and separated at low temperature into the 2-methylpentane distillation column, unreacted acetone is separated in the acetone distillation column, light component water is separated in the water-isopropanol distillation column, and pure MIBK product is obtained at the top of the methyl isobutyl ketone distillation column, with a high content of condensate in the bottom of the column.

[0060] According to some preferred embodiments of the present invention, water from an oil-water separator is discharged externally via an oil-water separator installed on the pipeline directly between the water-isopropanol distillation column and the methyl isobutyl ketone distillation column. The oil phase from the oil-water separator is then transported to the methyl isobutyl ketone distillation column.

[0061] According to some preferred embodiments of the present invention, a reboiler is provided below the 2-methylpentane distillation column. The heat-removing medium flowing out of the heat exchange outlet of the steam drum exchanges heat with the reboiler and then returns to the steam drum. The bottom temperature of the 2-methylpentane distillation column is around 70°C, which matches the temperature of the heat-removing medium. The vapor phase heat-removing medium in the steam drum can be used as the heating medium for the bottom of the 2-methylpentane distillation column. At the end of the reaction, as the reaction temperature increases, the temperature of the heat-removing medium also increases. The vapor phase heat-removing medium in the steam drum can also be used as the heating medium for the bottom of the acetone column (i.e., the acetone source), thus achieving both cooling of the vapor phase heat-removing medium in the steam drum and fully utilizing its heat.

[0062] Compared with the prior art, the present invention has the following advantages:

[0063] (1) The present invention adopts a new heat removal medium, increases the heat transfer coefficient of the reactor, improves the heat removal effect of the reactor, effectively controls the generation of reaction hot spot temperature, breaks through the bottleneck of reactor size limitation, and realizes the expansion of the production capacity of a single MIBK unit.

[0064] (2) Heat removal is achieved using a thermosiphon method, eliminating the need for a circulating pump and resulting in low energy consumption. Compared to a hot water heat removal process, the reaction apparatus for preparing MIBK in this invention saves one hot water cooler and one hot water circulating pump, reducing space and equipment investment, lowering energy consumption, and achieving better heat removal results.

[0065] (3) Compared with the conventional water cooling technology, the reaction device for preparing MIBK using the present invention has a larger production scale with one reactor; and with the same production scale, the original multiple parallel reactors are changed to a single reactor, which saves more on equipment investment. Attached Figure Description

[0066] Figure 1 This is a schematic diagram of the reaction apparatus for preparing MIBK according to the present invention.

[0067] 1 is the reactor; 2 is the steam drum; 3 is the heat exchange equipment; a is hydrogen from a hydrogen source; b is acetone from an acetone source; c is the heat removal medium from a heat removal medium source.

[0068] 101 is the vapor phase pipeline; 102 is the collection pipeline.

[0069] Figure 2 This is a schematic diagram of the reaction apparatus for preparing MIBK using water cooling in the prior art.

[0070] 1 is the reactor; a is hydrogen from the hydrogen source; b is acetone from the acetone source; A is the hot water tank; B is the hot water circulation pump; C is the hot water cooler.

[0071] Figure 3 This is a schematic diagram of the production system for preparing MIBK in this invention.

[0072] 1 is the reactor; 2 is the steam drum; 4 is the preheater; 5 is the condenser; 6 is the gas-liquid separator; 7 is the 2-methylpentane distillation column; 8 is the acetone distillation column; 9 is the water-isopropanol distillation column; 10 is the methyl isobutyl ketone distillation column; 11 is the oil-water separator; 12 is the reboiler; 13 is the heat removal medium reflux pump.

[0073] a represents hydrogen from a hydrogen source; b represents acetone from an acetone source; and c represents the heat removal medium from a heat removal medium source. Detailed Implementation

[0074] 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.

[0075] 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.

[0076] 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.

[0077] The reaction conditions for preparing MIBK, as well as the subsequent separation and purification conditions, in the following examples and comparative examples can all be referenced from existing technologies.

[0078] 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.

[0079] Example 1

[0080] like Figure 1 As shown, this embodiment 1 provides a reaction apparatus for preparing MIBK, which includes:

[0081] Includes a hydrogen source, an acetone source, reactor 1, a steam drum 2, a heat removal medium source, and a heat exchange device 3;

[0082] The reactor 1 is a tubular reactor; the reactor 1 includes a reactant inlet and a product outlet connected to the tube side of the reactor 1; the reactor 1 also includes a heat-removing medium inlet and a heat-removing medium outlet connected to the shell side of the reactor 1, the heat-removing medium inlet being located at the lower part of the reactor 1, and the heat-removing medium outlet being located at the upper part of the reactor 1; the heat-removing medium inlet of the reactor 1 includes four feed holes evenly distributed along the circumference of the reactor 1; the heat-removing medium outlet of the reactor 1 includes eight discharge holes evenly distributed along the circumference of the reactor 1; the steam drum 2 is a horizontal vessel; the steam drum 2 is positioned such that its bottom is higher than the top of the reactor 1; the height difference between the bottom of the steam drum 2 and the top of the reactor 1 is 7m;

[0083] Hydrogen a from a hydrogen source and acetone b from an acetone source enter the tube side of reactor 1 through the reactant inlet; heat removal medium c from a heat removal medium source enters steam drum 2. The liquid phase heat removal medium c enters the shell side of reactor 1 through multiple liquid outlets located at the lower part of the side wall of steam drum 2 via pipelines and multiple feed holes on the lower shell side of reactor 1. The liquid phase heat removal medium vaporizes in the shell side, and the latent heat of vaporization carries away the heat of the reaction in the tube side.

[0084] The reaction apparatus also includes: eight vapor phase pipelines 101, each connected to a discharge port located at the top of the reactor 1, and two collecting pipelines 102, each connected to a steam inlet of the steam drum 2. The vapor phase pipelines 101 extend upwards from the discharge port, and the height of the pipe openings of the vapor phase pipelines 101 furthest from the discharge port is flush with the height of the reactor 1. The eight vapor phase pipelines 101 are evenly distributed circumferentially around the reactor 1; thus, the flow path of the heat-removing medium within the reactor 1 is more uniform, resulting in better heat removal. Each collecting pipeline... The port of the collecting pipeline 102 away from the steam feed inlet is connected to four vapor phase pipelines 101, collecting the material from the vapor phase pipelines 101 into the collecting pipeline 102; the steam feed inlets are evenly distributed in the vapor phase space at the top of the steam drum 2; there are two steam feed inlets; in this way, the vaporized heat removal medium is collected in the collecting pipeline 102 through the discharge port of the reactor 1 via the vapor phase pipelines 101, and then rises into the steam drum 2 through the steam feed inlets of the steam drum 2; the steam feed inlets are evenly distributed in the vapor phase space at the top of the steam drum 2.

[0085] The aforementioned heat-removing medium enters the shell side of reactor 1 from the bottom and exits from the top. During this process, the heat-removing medium absorbs the heat of reaction. As the temperature rises, the heat-removing medium thermally expands, the hot fluid rises, and the cold fluid replaces the hotter fluid in the circulation loop. This thermal expansion creates a density gradient between the inlet (heat-removing medium inlet) and outlet (heat-removing medium outlet) of reactor 1's shell side. This density difference causes the condensate in the steam drum to be continuously siphoned into the shell side of reactor 1, and the heated and vaporized gas-liquid mixture automatically returns to the steam drum, forming a natural circulation. In this invention, the heat-removing medium enters the shell side in a liquid state and then vaporizes for heat removal. This allows for heat removal via thermosiphon, eliminating the need for a circulating pump and reducing energy consumption. Multiple heat-removing medium outlets ensure a more uniform flow path within the reactor, resulting in better heat removal. The vapor phase pipeline 101 converges to the collection pipeline 102 before being sent to the steam drum 2, effectively reducing the number of connecting pipelines between reactor 1 and steam drum 2. This is more advantageous in terms of pipeline layout, support, and construction effort.

[0086] The steam drum 2 is also connected to the heat exchange device 3 via pipeline to form a closed loop; the steam drum 2 includes a heat exchange outlet and a heat exchange inlet connected to the heat exchange device 3, the heat exchange outlet is located at the top of the steam drum 2, and the heat exchange inlet is located on the side wall of the steam drum 2; in this way, the vaporized heat-removing medium carrying heat flowing in from the tube side of the reactor 1 is cooled after passing through the heat exchange device 3, and the liquid phase heat-removing medium returns to the steam drum 2.

[0087] The reactor 1 is filled with catalyst in its tubular section; the heat exchange device 3 is the reboiler for the downstream 2-methylpentane distillation column.

[0088] The heat-relief medium is an organic reagent with a boiling point of 50-80℃; in this embodiment, acetone is selected.

[0089] The reactor in this embodiment has a diameter of 9m, a height of 6m, and a length-to-diameter ratio of 0.67.

[0090] This embodiment 1 also provides a method for controlling the temperature conditions for preparing MIBK using the reaction apparatus for preparing MIBK described in embodiment 1, including:

[0091] In the initial stage of the reaction, acetone preheated to 85-88°C through a steam pipeline is introduced into the shell side of reactor 1, which activates the catalyst in the tube side of reactor 1 and causes the acetone hydrogenation reaction to produce a reaction product containing MIBK.

[0092] After the reaction begins, liquid acetone is introduced into the shell side of reactor 1. The acetone vaporizes in the shell side of reactor 1, removing some of the heat from the acetone hydrogenation reaction, so that the temperature of the tube side of reactor 1 is maintained within the target temperature range; the temperature of the acetone in the shell side is 3-5°C lower than the target temperature of the tube side of reactor 1.

[0093] The vaporized acetone obtained from the shell side of the reactor 1 rises to the steam drum 2, and is then cooled by the heat exchanger 3, returning to the steam drum 2 in the form of liquid acetone. The liquid heat removal medium then enters the shell side of the reactor 1 for heat removal, and the cycle continues.

[0094] In the above process, liquid acetone in the steam drum 2 enters the shell side of the reactor 1 by siphon.

[0095] The reactor in this embodiment has a diameter of 9m, a height of 6m, and an aspect ratio of 0.67. The conventional reactor has a diameter of 2.6m, a height of 6m, and an aspect ratio of 2.31. Using the above-mentioned reaction device of the present invention, a larger production scale can be achieved, and the heat removal requirements for MIBK preparation can be met even with a significantly increased scale.

[0096] Comparative Example 1

[0097] Comparative Example 1 illustrates a conventional heat removal method using hot water. This method relies on the increase in water temperature to absorb the heat of reaction. However, this simple method of heat removal through water temperature change results in slow flow velocity of the hot water in the reactor shell side, uneven flow field, low heat transfer coefficient, and poor heat transfer effect. For example... Figure 2 As shown, the heat removal medium is hot water. The hot water is pushed by hot water circulation pump B, cooled by hot water cooler C, and then enters the shell side of reactor 1, carrying away heat before returning to hot water tank A. To meet the heat removal requirements for MIBK preparation, the reactor suitable for Comparative Example 1 has a diameter of 2.6m, a height of 6m, and an aspect ratio of 2.31. If the reactor diameter is further increased, i.e., the aspect ratio is reduced, the heat removal effect will deteriorate, leading to catalyst runaway deactivation, reduced reaction conversion rate, and product defects, thus failing to meet the heat removal requirements for MIBK preparation. To expand production scale, multiple reactors with a diameter of 2.6m and a height of 6m would need to be connected in parallel.

[0098] Furthermore, Comparative Example 1 not only suffers from the limitation of scaling up the single-reactor MIBK reactor, but also from unstable heat removal: 1) Due to the use of water for heat removal, the reaction temperature is 90-95℃ in the initial stage, while the boiling point of hot water at atmospheric pressure is 100℃. Therefore, the latent heat of the water cannot be utilized for heat removal; only sensible heat can be used. The hot water is unevenly distributed in the shell side of the reactor, with a low flow rate, resulting in a low heat transfer coefficient and affecting heat exchange efficiency. 2) Simultaneously, to make the reaction more uniform and controllable, the temperature difference between the hot water inlet and outlet in the shell side needs to be minimized. A smaller temperature difference results in a larger hot water circulation volume. For economic reasons, a temperature difference of 5℃ is typically used. In this situation, if the hot water enters from the bottom and exits from the top, the most vigorous reaction occurs at the reactor inlet, where the hot water temperature used for heat removal is highest, affecting heat exchange. If the hot water enters from the top and exits from the bottom, the preheating of the reaction tube inlet is poor, affecting reaction activation. Improper heat removal during these processes can easily create reaction hotspots, causing catalyst deactivation and unit shutdown.

[0099] Compared with Comparative Example 1, the advantages are:

[0100] (1) The present invention adopts a new heat removal medium, increases the heat transfer coefficient of the reactor, improves the heat removal effect of the reactor, effectively controls the generation of reaction hot spot temperature, breaks through the bottleneck of reactor size limitation, and realizes the expansion of the production capacity of a single MIBK unit.

[0101] (2) Heat removal is achieved using a thermosiphon method, eliminating the need for a circulating pump and resulting in low energy consumption. Compared to the hot water heat removal process, the reaction apparatus for preparing MIBK in this invention saves one hot water cooler and one hot water circulating pump, thus saving space and equipment investment, reducing energy consumption, and achieving better heat removal effect.

[0102] (3) Compared with conventional water cooling technology, the reaction apparatus of the present invention for preparing MIBK has a larger production scale with only one reactor.

[0103] The reason for this technological breakthrough lies in the fact that the latent heat of vaporization of acetone in this invention replaces hot water for heat removal. Utilizing the latent heat of vaporization of acetone for heat removal, the reactor shell side is a two-phase gas-liquid system. Acetone has no dead zones in the shell side, unlike water heat removal which suffers from slow flow velocity and uneven distribution due to the presence of baffles, resulting in uniform temperature in both the radial and axial directions of the shell side. This ensures that the temperature in the shell side (the low-temperature side) is the same from top to bottom, maintaining a constant heat transfer temperature difference, a high heat transfer coefficient, and better and more stable heat removal performance. Therefore, a single reactor can be used to expand the production scale of MIBK reactors, solving the long-standing bottleneck problem of not being able to achieve large-scale production of MIBK reactors using a single reactor, achieving unexpected technological results.

[0104] Furthermore, in the reaction apparatus for preparing MIBK according to Embodiment 1 of this invention, acetone enters the reactor shell from the bottom and exits from the top. During this process, the heat removal medium absorbs the heat of reaction. As the temperature rises, the heat removal medium thermally expands, the hot fluid rises, and the cold fluid replaces the hotter fluid in the circulation loop. The thermal expansion creates a density gradient between the reactor shell inlet (heat removal medium inlet) and the reactor shell outlet (heat removal medium outlet). The density difference causes the condensate in the steam drum to be continuously siphoned into the reactor shell, and the heated and vaporized gas-liquid mixture automatically returns to the steam drum, forming a natural circulation. Acetone enters the shell from a liquid state and then vaporizes for heat removal. This allows for heat removal via thermosiphon, eliminating the need for a circulating pump to drive the feed, resulting in lower energy consumption. Moreover, the vaporized heat removal medium, after flowing out of the shell, can be used as a heat source for other devices, such as the reboiler in the separation unit, thus utilizing the heat. In this process, the vaporized heat removal medium is cooled after heat exchange, returns to the liquid phase, and is recycled as the heat removal medium for the shell. In this way, compared to water-based heat removal, it can save a heat exchanger and a pump, reducing equipment investment and floor space, while also reducing energy consumption.

[0105] Example 2

[0106] The method for controlling the temperature conditions for preparing MIBK using the reaction apparatus and reaction apparatus for preparing MIBK in Example 1 differs in that the heat removal medium selected in this example is ethanol.

[0107] It has been verified that the boiling point of ethanol at normal pressure is 78.3℃, which can meet the heat transfer temperature difference requirements of the reactor heat removal medium and can meet the heat removal requirements of this invention.

[0108] Example 3

[0109] The method for controlling the temperature conditions for preparing MIBK using the reaction apparatus and reaction apparatus for preparing MIBK in Example 1 is different in that the heat removal medium selected in this example is tetrahydrofuran.

[0110] It has been verified that tetrahydrofuran has a boiling point of 66°C at atmospheric pressure, which can meet the temperature difference requirements for heat transfer in the reactor and satisfy the heat removal requirements of this invention.

[0111] Example 4

[0112] The method for controlling the temperature conditions for preparing MIBK using the reaction apparatus for preparing MIBK described in Example 1 differs in that...

[0113] The reactor in this embodiment has a diameter of 6m, a height of 6m, and a length-to-diameter ratio of 1. Using the above-described reaction device of the present invention, the heat removal requirements for MIBK preparation can be met even with a significantly increased scale.

[0114] It has been verified that Example 4 can also meet the heat removal requirements of the present invention.

[0115] Example 5

[0116] The method for controlling the temperature conditions for preparing MIBK using the reaction apparatus for preparing MIBK described in Example 1 differs in that...

[0117] The inlet of the deheating medium of the reactor 1 includes three feed holes evenly distributed along the circumference of the reactor 1; the outlet of the deheating medium of the reactor 1 includes six discharge holes evenly distributed along the circumference of the reactor 1.

[0118] Each collecting pipeline 102 has a port away from the gas feed inlet connected to three vapor phase pipelines 101, and there are two gas feed inlets.

[0119] It has been verified that Example 5 can also meet the heat removal requirements of the present invention.

[0120] Example 6

[0121] The method for controlling the temperature conditions for preparing MIBK using the reaction apparatus for preparing MIBK described in Example 1 differs in that...

[0122] The bottom of the steam drum 2 is higher than the top of the reactor 1; the height difference between the bottom of the steam drum 2 and the top of the reactor 1 is 12m.

[0123] It has been verified that Example 6 can also meet the heat removal requirements of the present invention.

[0124] Example 7

[0125] like Figure 3 As shown, this embodiment provides a production system for preparing MIBK, including the reaction apparatus for preparing MIBK in Embodiment 1, and further including two preheaters 4, a condenser 5, a separator 6, and multiple distillation columns; one preheater 4 is located in the passage connecting the hydrogen source and the reactant inlet of the reactor 1, and the other preheater 4 is located in the passage connecting the acetone source and the reactant inlet of the reactor 1; the reaction product outlet of the reactor 1 is sequentially connected to the condenser 5, the separator, and multiple distillation columns connected in series; the separator is a gas-liquid separator 6, the gas outlet of the gas-liquid separator 6 is connected to the reactant inlet of the reactor 1, and the liquid outlet of the gas-liquid separator 6 is connected to the feed inlet of the first distillation column; the number of distillation columns is four, named according to the flow direction of the bottom material of each distillation column and the distillate from the top of the column, the four distillation columns are sequentially: 2-methylpentane distillation column 7, acetone distillation column 8, water-isopropanol distillation column 9, and methyl isobutyl ketone distillation column 10;

[0126] A reboiler 12 is installed below the 2-methylpentane distillation column 7. The heat exchange outlet of the steam drum 2 is connected to the heat exchange inlet of the steam drum 2 via the reboiler 12 and the heat removal medium reflux pump 13 to form a closed loop. The top outlet of the acetone distillation column 8 is connected to the reactant inlet of the reactor 1. An oil-water separator 11 is installed on the pipeline between the water-isopropanol distillation column 9 and the methyl isobutyl ketone distillation column 10. The water outlet of the oil-water separator 11 is open to the outside, and the oil phase outlet of the oil-water separator 11 is connected to the methyl isobutyl ketone distillation column 10.

[0127] This embodiment also provides a production method for preparing MIBK using the production system described in this embodiment, including:

[0128] Hydrogen and acetone, preheated by preheater 4, are introduced into the tube side of reactor 1. The acetone and hydrogen are then contacted with a catalyst for a hydrogenation reaction, yielding a reaction product containing MIBK. This MIBK-containing reaction product is then cooled by condenser 5 and separated into gaseous and liquid phases using a separator. Optionally, the gaseous phase separated by the separator is returned to the tube side of reactor 1, and the liquid phase separated by the separator is further purified by multiple distillation columns connected in series to obtain the target MIBK product.

[0129] The conditions for the hydrogenation reaction include controlling the temperature for preparing MIBK using the following method:

[0130] In the initial stage of the reaction, acetone preheated to 85-88°C through a steam pipeline is introduced into the shell side of reactor 1, which activates the catalyst in the tube side of reactor 1 and causes the acetone hydrogenation reaction to produce a reaction product containing MIBK.

[0131] After the reaction begins, liquid acetone is introduced into the shell side of reactor 1. The acetone vaporizes in the shell side of reactor 1, removing some of the heat from the acetone hydrogenation reaction, so that the temperature of the tube side of reactor 1 is maintained within the target temperature range; the temperature of the acetone in the shell side is 3-5°C lower than the target temperature of the tube side of reactor 1.

[0132] The vaporized acetone obtained in the shell side of the reactor 1 rises to the steam drum 2, and is then cooled by the heat exchanger 3, returning to the steam drum 2 in the form of liquid acetone. The liquid heat removal medium then enters the shell side of the reactor 1 for heat removal, and the cycle continues. During the above process, the liquid acetone in the steam drum 2 enters the shell side of the reactor 1 by siphon.

[0133] The distillation column consists of four columns, named according to the flow direction of the material at the bottom and the distillate at the top. The four distillation columns are, in order: 2-methylpentane distillation column 7, acetone distillation column 8, water-isopropanol distillation column 9, and methyl isobutyl ketone distillation column 10. Through the distillation separation of the four columns, 2-methylpentane, acetone, a mixture of water and isopropanol, and methyl isobutyl ketone are obtained sequentially at the top of the columns. The acetone obtained from the distillation separation is returned to the tube side of the reactor 1.

[0134] Water is collected from an oil-water separator 11 installed on the pipeline directly between the water-isopropanol distillation column 9 and the methyl isobutyl ketone distillation column 10, and the oil phase of the oil-water separator 11 is transported to the methyl isobutyl ketone distillation column 10.

[0135] A reboiler 12 is provided below the 2-methylpentane distillation column 7. The heat removal medium flowing out of the heat exchange outlet of the steam drum 2 exchanges heat with the reboiler and then returns to the steam drum 2.

[0136] The production system and method for preparing MIBK in this embodiment continue the advantages of Embodiment 1, with a higher production scale, more stable heat removal, and the ability to save equipment.

[0137] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

[0138] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0139] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application’s filing, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0140] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values; such ranges or values ​​should be understood to include values ​​close to them. 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 principle, various technical solutions can be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0141] In the context of this specification, except where expressly stated otherwise, any matters or issues not mentioned shall apply directly to those known in the art without any modification.

[0142] Furthermore, any implementation described herein can be freely combined with one or more other implementations described herein, and the resulting technical solutions or technical ideas shall be regarded as part of the original disclosure or original record of the present invention, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider the combination to be obviously unreasonable.

Claims

1. A reaction apparatus for preparing MIBK, comprising a reactor, a steam drum, a heat removal medium source, and a heat exchange device; The reactor is a shell-and-tube reactor, which includes a reactant inlet and a product outlet connected to the tube side of the reactor. The reactor also includes a heat-removing medium inlet and a heat-removing medium outlet connected to the shell side of the reactor. The heat-removing medium inlet is located at the lower part of the reactor, and the heat-removing medium outlet is located at the upper part of the reactor. The steam drum is connected to the heat removal medium source via a pipeline; the steam drum also includes a liquid phase outlet and a vapor phase inlet, the liquid phase outlet is connected to the heat removal medium inlet of the reactor via a pipeline, and the vapor phase inlet is connected to the heat removal medium outlet of the reactor via a pipeline. The steam drum is also connected to the heat exchange equipment via pipelines to form a closed-loop circulation.

2. The reaction apparatus according to claim 1, characterized in that: The reactant inlet is connected to a hydrogen source and an acetone source; and / or, The heat-relief medium is an organic reagent with a boiling point of 50-80℃, preferably selected from at least one of acetone, methanol, ethanol, and tetrahydrofuran; more preferably, it is acetone.

3. The reaction apparatus according to claim 1, characterized in that: The steam drum is a horizontal container; and / or, The bottom of the steam drum is higher than the top of the reactor; preferably, the height difference between the bottom of the steam drum and the top of the reactor is 1-20m; and / or, The steam drum includes a heat exchange outlet and a heat exchange inlet connected to the heat exchange equipment. The heat exchange outlet is located at the top of the steam drum, and / or the heat exchange inlet is located on the side wall of the steam drum; and / or, A heat removal medium return pump is installed in the closed-loop circulation path connecting the steam drum and the heat exchange equipment.

4. The reaction apparatus according to claim 1, characterized in that: The reactor's heat dissipation medium inlet includes a plurality of feed holes distributed circumferentially along the reactor. The liquid phase outlet of the steam drum includes multiple liquid outlets located at the bottom or lower side wall of the steam drum, and each liquid outlet is connected to the feed port of the reactor through a pipeline. Preferably, the number of feed holes is 2-20, more preferably 2-4; and / or, the plurality of feed holes are evenly distributed along the circumference of the reactor.

5. The reaction apparatus according to claim 1, characterized in that: The reactor's heat dissipation medium outlet includes multiple discharge holes distributed circumferentially along the reactor; the steam drum's vapor phase inlet includes multiple steam feed inlets located at the top of the steam drum; each steam feed inlet is connected to the reactor's discharge hole via a pipeline; preferably, The reaction apparatus further includes: multiple vapor phase pipelines, each connected to the outlet of the reactor, and multiple collecting pipelines, each connected to the steam inlet of the steam drum, wherein the collecting pipelines are connected to at least one vapor phase pipeline. More preferably, the vapor phase pipeline extends upward from the discharge port, with the height of the extended pipe opening being flush with the height of the reactor; most preferably, multiple vapor phase pipelines are evenly distributed circumferentially at the top of the reactor; and / or, 2-4 vapor phase lines are connected to the same manifold; and / or, The number of discharge holes is 4-20, preferably 6-8; and / or, the plurality of discharge holes are evenly distributed along the circumference of the reactor; and / or, The gas feed inlets are evenly distributed on the top of the gas drum; and / or, the number of gas feed inlets is 2-6.

6. The reaction apparatus according to any one of claims 1-5, characterized in that: The reactor has an aspect ratio of 0.2-5, preferably 0.5-3; more preferably 0.5-2.5; and / or, The reactor is a tubular reactor; and / or, The reactor tubes are packed with catalyst; and / or, The heat exchange equipment is a device that needs to absorb heat, preferably at least one of a heat exchanger and a reboiler; and / or The reactor shell side is provided with baffles. Preferably, the baffles are a combination of one or more of the following: baffle rods and perforated plates.

7. A production system for preparing MIBK, comprising the reaction apparatus for preparing MIBK as described in any one of claims 1-6, preferably, The MIBK production system also includes a preheater, a condenser, a gas-liquid separator, and a separation unit; in, Preheaters are installed on the passages connecting the hydrogen source, the acetone source, and the reaction raw material inlet of the reactor, respectively. The reactor's reaction product outlet is sequentially connected to the condenser, gas-liquid separator, and separation unit.

8. The production system according to claim 7, characterized in that: The gas outlet of the gas-liquid separator is connected to the reaction feed inlet of the reactor and the hydrogen source via a pipeline; the liquid outlet of the gas-liquid separator is connected to the feed inlet of the separation unit; and / or, The separation unit includes multiple distillation columns connected in series. Preferably, the number of distillation columns is four, including a 2-methylpentane distillation column, an acetone distillation column, a water-isopropanol distillation column, and a methyl isobutyl ketone distillation column connected in sequence; more preferably, A reboiler is provided below the 2-methylpentane distillation column, and the heat exchange outlet of the steam drum is connected to the heat exchange inlet of the steam drum through the reboiler to form a closed loop; and / or, The acetone distillation column's top outlet is connected to the acetone source and reactant inlet of the reactor via a pipeline; and / or, An oil-water separator is installed on the pipeline between the water-isopropanol distillation column and the methyl isobutyl ketone distillation column, and the water outlet of the oil-water separator is open to the outside.

9. A method for controlling the temperature conditions for preparing MIBK using the reaction apparatus for preparing MIBK according to any one of claims 1-6, comprising: In the initial stage of the reaction, the heat-removing medium from the heat-removing medium source is preheated and then introduced into the shell side of the reactor to activate the catalyst in the tube side of the reactor. After that, the reaction raw materials are added to the tube side of the reactor to start the acetone hydrogenation reaction. After the reaction begins, a liquid-phase heat-removing medium is introduced into the shell side of the reactor. The liquid-phase heat-removing medium vaporizes in the shell side of the reactor, removing part of the heat from the acetone hydrogenation reaction. Preferably, the temperature of the heat-removing medium in the shell side is 3-5°C lower than the target temperature in the tube side of the reactor. The vaporized heat-removing medium obtained by vaporization in the shell side of the reactor rises to the steam drum, is cooled by a heat exchanger, and returns to the steam drum as a liquid heat-removing medium. The liquid heat-removing medium then enters the shell side of the reactor for heat removal, and the cycle continues. Preferably, the liquid-phase heat removal medium in the steam drum is siphoned into the shell side of the reactor; and / or, Preferably, the temperature of the preheated heat-removing medium is 85-88°C.

10. A method for preparing MIBK using the production system described in claim 7 or 8: Hydrogen and acetone, preheated by a preheater, are introduced into the tube side of the reactor. The acetone and hydrogen are then contacted with a catalyst for a hydrogenation reaction, yielding a reaction product containing MIBK. This MIBK-containing reaction product is then cooled by a condenser, and a gas-liquid separator is used to separate the gaseous and liquid phases. Optionally, the gaseous phase separated by the gas-liquid separator is returned to the tube side of the reactor, and the liquid phase separated by the gas-liquid separator is further separated by a separation unit to obtain the target MIBK product. Preferably, The conditions for the hydrogenation reaction include: The temperature for preparing MIBK is controlled using the method described in claim 9; more preferably, The separation unit includes multiple distillation columns connected in series, more preferably four, connected in sequence as follows: a 2-methylpentane distillation column, an acetone distillation column, a water-isopropanol distillation column, and a methyl isobutyl ketone distillation column; through the distillation separation of the four distillation columns, 2-methylpentane, acetone, a mixture of water and isopropanol, and methyl isobutyl ketone are obtained sequentially; most preferably, the acetone obtained from the distillation separation is returned to the tube side of the reactor; and / or, Water from the oil-water separator is discharged externally via an oil-water separator installed on the pipeline directly between the water-isopropanol distillation column and the methyl isobutyl ketone distillation column; and / or, A reboiler is installed below the 2-methylpentane distillation column. The heat removal medium flowing out of the heat exchange outlet of the steam drum exchanges heat with the reboiler and then returns to the steam drum.

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