A microchannel reactor for propionic acid ester synthesis

Abstract

This utility model belongs to the field of lithium battery electrolyte additive propionate production technology, specifically a microchannel reactor for propionate synthesis. It includes a first heat-conducting layer, a material layer, and a second heat-conducting layer arranged sequentially from top to bottom. Heat exchange channels are formed within both the first and second heat-conducting layers, and material channels are formed within the material layer. Several reaction modules are sequentially arranged within the material channels along the material flow direction. Each reaction module includes at least one heat-conducting frame, within which a catalyst is fixed to form a fixed bed. Flow channels in the same direction as the material flow are formed between the heat-conducting frames of each reaction module, and / or between the heat-conducting frame and the bottom wall of the material channel, and / or between the heat-conducting frame and the top wall of the material channel. The flow channels of adjacent reaction modules are staggered. This application achieves multiple contacts between the reactants and the catalyst through the staggered flow paths, thereby increasing flow efficiency and improving reaction efficiency.

Description

Technical Field

[0001] This invention belongs to the field of lithium battery electrolyte additive propionate production technology, specifically a microchannel reactor for propionate synthesis. Background Technology

[0002] The application of propionate esters in lithium-ion battery electrolytes is based on their excellent solvent properties, stability, and low toxicity. They can improve the ionic conductivity of the electrolyte, enhance low-temperature performance, extend battery cycle life, and improve electrode compatibility. Therefore, propionate esters are an ideal component of lithium-ion battery electrolytes and are of great significance for improving battery performance and reliability.

[0003] Currently, the industrial production of propionate esters mainly employs traditional batch reactors for the catalytic esterification reaction of propionic acid with corresponding alcohols. This batch or semi-batch production method has many inherent drawbacks, making it difficult to meet the growing demand for high-quality and large-scale propionate esters from the lithium battery industry. Microchannel reactor technology, with its core advantages such as extremely large specific surface area, excellent heat and mass transfer performance, precise fluid control, and ease of continuous operation, offers a revolutionary solution for the efficient, safe, and green synthesis of chemicals. Applying it to the synthesis of propionate esters holds the promise of fundamentally overcoming the aforementioned shortcomings of batch processes. However, designing a microchannel reactor suitable for propionate ester synthesis still requires addressing the following key issues:

[0004] (1) The problem of catalyst immobilization and heat transfer coupling: How to efficiently and stably immobilize the catalyst in the microchannel and ensure that the heat generated during the reaction can be removed quickly and uniformly to prevent local overheating from causing catalyst deactivation or aggravating side reactions is the key to the design.

[0005] (2) Reactant mixing and contact efficiency: The rapid and thorough mixing of the acid and alcohol in the microchannel, as well as the sufficient and effective contact with the supported catalyst, directly affects the reaction efficiency and product yield. Simple straight-channel or single catalyst bed designs may not be able to achieve the optimal contact effect.

[0006] Therefore, there is an urgent need in this field to develop a novel microchannel reactor that is tailored to the characteristics of propionate synthesis reactions, has a reasonable structural design, and can effectively solve the above-mentioned problems. Utility Model Content

[0007] To address the problems mentioned above in the background art, this utility model provides a microchannel reactor for propionate synthesis.

[0008] The present invention adopts the following technical solution:

[0009] A microchannel reactor for propionate synthesis includes a first heat-conducting layer, a material layer, and a second heat-conducting layer arranged sequentially from top to bottom. Heat exchange channels extending along the material flow direction are formed in both the first and second heat-conducting layers, and material channels are formed in the material layer.

[0010] A feeding channel is provided at one end of the material channel, and a discharging channel is provided at the other end. Both the feeding channel and the discharging channel avoid the heat exchange channel.

[0011] Several reaction modules are arranged sequentially along the material flow direction in the material channel. Each reaction module includes at least one heat-conducting frame, and a catalyst is fixed in the heat-conducting frame to form a fixed bed. Flow channels in the same direction as the material flow are formed between the heat-conducting frames of each reaction module, and / or between the heat-conducting frame and the bottom wall of the material channel, and / or between the heat-conducting frame and the top wall of the material channel. The flow channels of two adjacent reaction modules are staggered.

[0012] Furthermore, the thermally conductive frame is a metal mesh structure, and the catalyst is uniformly fixed on the metal mesh structure.

[0013] Furthermore, each reaction module includes a heat-conducting frame, and the width of the heat-conducting frame is the same as the width of the material channel, so that a flow channel is formed between the heat-conducting frame and the bottom or top wall of the material channel, and adjacent flow channels are arranged vertically.

[0014] Furthermore, each reaction module includes a heat-conducting frame, and the height of the heat-conducting frame is the same as the height of the material channel, so that a flow channel is formed between the heat-conducting frame and the side wall of the material channel, and the adjacent flow channels are arranged in a front-to-back structure.

[0015] Furthermore, there are two feed channels, namely the first feed channel and the second feed channel. The acid material enters the feed channel through the first feed channel, and the alcohol material enters the feed channel through the second feed channel. The catalyst is a solid protic acid catalyst.

[0016] Furthermore, the medium within the first and second heat-conducting layers includes one or more of ceramics, glass, and metals.

[0017] Furthermore, the material of the heat-conducting frame includes one or more of ceramic, glass, and metal.

[0018] Furthermore, it also includes a separatory tank connected to the discharge channel, with the organic phase outlet of the separatory tank connected to one of the feed channels of another microchannel reactor, and the aqueous phase outlet of the separatory tank connected to the aqueous phase separatory tank.

[0019] Furthermore, it also includes a pressure pump, which is connected in the material channel and uses pressure to push the material through the material channel and discharge the product from the discharge channel.

[0020] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0021] (1) In the microchannel reactor of this application, several reaction modules are sequentially arranged in the material channel along the material flow direction. Each reaction module includes at least one thermally conductive frame, and a catalyst is fixed in the thermally conductive frame to form a fixed bed. Flow channels in the same direction as the material flow are formed between the thermally conductive frames of each reaction module, and / or between the thermally conductive frame and the bottom wall of the material channel, and / or between the thermally conductive frame and the top wall of the material channel. The flow channels of two adjacent reaction modules are staggered. By setting multiple reaction modules and staggering the flow paths of adjacent reaction modules, this application enables the reactants to form multiple contacts on the catalyst surface, prolonging the effective reaction time and increasing the flow efficiency, thereby improving both reaction efficiency and ensuring a complete reaction.

[0022] (2) The thermally conductive frame of this application is a metal mesh structure. The catalyst is uniformly fixed on the metal mesh structure to form a fixed bed. The metal mesh structure has a high thermal conductivity, which can realize the conduction of heat during the catalytic process and avoid the reaction temperature from being too high. At the same time, the pores on the metal mesh structure allow the material to fully penetrate and fully contact the catalyst on the metal mesh structure. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A side view of a microchannel reactor provided in an embodiment of this application;

[0025] Figure 2 A top view of a microchannel reactor provided in another embodiment of this application;

[0026] Figure 3 This is a schematic diagram showing the connection between a microchannel reactor and a separatory tank according to an embodiment of this application;

[0027] Wherein: 1-first heat-conducting layer, 2-material layer, 21-material channel, 22-top wall, 23-bottom wall, 24-side wall, 3-second heat-conducting layer, 4-feed channel, 5-discharge channel, 6-heat-conducting frame, 7-catalyst, 8-flow channel, 9-liquid separator, 10-aqueous phase separator, 11-microchannel reactor. Detailed Implementation

[0028] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0029] The following is in conjunction with the appendix Figure 1 To be continued Figure 3 The present invention will be described in detail with specific embodiments.

[0030] like Figure 1-3 As shown, this utility model provides a microchannel reactor for propionate synthesis, comprising a first heat-conducting layer 1, a material layer 2, and a second heat-conducting layer 3 arranged sequentially from top to bottom. Heat exchange channels extending along the material flow direction are formed in both the first heat-conducting layer 1 and the second heat-conducting layer 3, and a material channel 21 is formed in the material layer 2. The heat exchange channels are filled with a heat-conducting medium to ensure that the heat of reaction is uniformly discharged through the heat-conducting medium.

[0031] One end of the material channel 21 is provided with a feed channel 4 and the other end is provided with a discharge channel 5. Both the feed channel 4 and the discharge channel 5 avoid the heat exchange channel. Preferably, the number of feed channels 4 is the same as the number of reactants, and each feed channel 4 corresponds to one reactant.

[0032] Several reaction modules are sequentially arranged within the material channel 21 along the material flow direction. These reaction modules are unit structures distributed sequentially along the material flow direction, and all reaction modules are independent of each other. Each reaction module includes at least one heat-conducting frame 6. When there are more than one heat-conducting frame 6, all heat-conducting frames 6 are also independent of each other. A catalyst 7 is fixed within each heat-conducting frame 6 to form a fixed bed. Optionally, the catalyst 7 is fixed to the heat-conducting frame 6 by sintering or coating to form a structured fixed bed. The heat-conducting frames 6 of each reaction module are arranged between each other, and / or between the heat-conducting frames 6 and the bottom wall 23 of the material channel 21. Flow channels 8, in the same direction as the material flow, are formed between the thermally conductive frame 6 and the top wall 22 of the material channel 21. In other words, all the thermally conductive frames 6 within the microchannel reactor 11 are independent of each other. Based on the size and position of the thermally conductive frames 6, multiple flow channels 8 in the same direction as the material flow are formed. The flow channels 8 of adjacent reaction modules are staggered. For example, if there are two reaction modules, namely the first reaction module and the second reaction module, all flow channels 8 of the first reaction module and all flow channels 8 of the second reaction module are staggered to ensure that all materials can contact the fixed bed. It should be noted that this application does not limit the number of reaction modules or the number of thermally conductive frames 6 contained in each reaction module. As long as the staggered arrangement of the flow channels 8 can be achieved, increasing the contact opportunity between the material and the catalyst, it falls within the scope of protection of this application.

[0033] The process for synthesizing propionate using the microchannel reactor of this application is as follows:

[0034] Two feed channels 4 are provided at one end of the material channel 21. Acid and alcohol are injected into the material layer 2 through two independent feed channels 4. When the material flows through the heat-conducting frame 6 of the first reaction module, some material passes through the flow channel 8, while the rest passes through the fixed bed. Then, it enters the second reaction module. Because the flow channel 8 of the second reaction module is misaligned with that of the first reaction module, material that did not flow through the fixed bed in the first reaction module flows through the fixed bed in the second reaction module. Material that flowed through the fixed bed in the first reaction module may flow through the fixed bed in the second reaction module, or it may enter the third reaction module through the flow channel 8 in the second reaction module, and so on, to complete the synthesis reaction. During the reaction, the heat-conducting frame 6 of each reaction module has a heat-conducting function, allowing the reaction heat to enter the first heat-conducting layer 1 and the second heat-conducting layer 3. The heat is then carried away in time by the heat-conducting medium in the heat exchange channel. Finally, the reaction product is discharged from the discharge channel and then enters the subsequent phase separation equipment. This application sets up multiple reaction modules, and the staggered flow paths of adjacent reaction modules enable the reactants to form multiple contacts on the catalyst surface, thereby extending the effective reaction time and increasing the flow efficiency. This not only improves the reaction efficiency but also ensures a complete reaction.

[0035] As is understood, a fixed-bed reactor is a structure in which solid catalyst particles are statically packed, allowing reactants to flow through the bed for catalytic reaction. It has advantages such as low catalyst loss, high conversion rate, good selectivity, and relatively simple structure. In this application, fixing the catalyst in a thermally conductive frame can promptly remove the heat generated during the reaction.

[0036] Furthermore, in a preferred embodiment, the heat-conducting frame 6 is a metal mesh structure. The metal mesh structure can be formed by weaving or welding metal wires or sheets, and it is a three-dimensional porous skeleton. At the same time, the catalyst is uniformly fixed on the metal mesh structure. The metal mesh structure has a high thermal conductivity, which can realize the conduction of heat. Meanwhile, the pores on the metal mesh structure allow the material to fully penetrate and fully contact the catalyst on the metal mesh structure.

[0037] For further details, please refer to [link / reference]. Figure 1 In some embodiments, each reaction module includes a heat-conducting frame 6, and the width of the heat-conducting frame 6 is the same as the width of the material channel 21, that is, the same lateral dimension. This allows the flow channel 8 to be formed only between the heat-conducting frame 6 and the bottom wall 23 or top wall 22 of the material channel 21, and adjacent flow channels 8 are arranged vertically. The above technical features make it impossible for the material to bypass the front and rear sides of the heat-conducting frame 6 in the lateral direction, but it must pass through the flow channel 8 between the heat-conducting frame 6 and the bottom wall 23 or top wall 22 of the material channel 21. When the material flows through the first heat-conducting frame, some of the material passes through the first heat-conducting frame, and the other part of the material flows through the flow channel 8. When it enters the second heat-conducting frame, the material that has not participated in the reaction comes into contact with the second heat-conducting frame and reacts. This process is repeated to ensure that all the material is in full contact with the catalyst. At the same time, the contact between the heat-conducting frame 6 and the first heat-conducting layer 1 or the second heat-conducting layer 3 is more conducive to heat transfer and avoids the catalyst from losing its activity due to excessive temperature.

[0038] For further details, please refer to [link / reference]. Figure 2 In some embodiments, each reaction module includes a heat-conducting frame 6, and the height of the heat-conducting frame 6 is the same as the height of the material channel 21, so that a flow channel 8 is formed between the heat-conducting frame 6 and the side wall 24 of the material channel 21, and the adjacent flow channels 8 are arranged in a front-to-back structure. The above technical features make it impossible for the material to bypass the upper and lower sides of the heat-conducting frame 6, but must pass through the flow channel 8 between the heat-conducting frame 6 and the side wall 24 of the material channel 21. When the material flows through the first heat-conducting frame, part of the material passes through the first heat-conducting frame, and the other part of the material flows through the flow channel 8. When it enters the second heat-conducting frame, the material that has not participated in the reaction comes into contact with the second heat-conducting frame and reacts. This process is repeated to ensure that all materials are in full contact with the catalyst and the reaction is completed.

[0039] This application uses alternating staggered flow channels 8 to ensure that the material is in full contact with the fixed bed, ensuring that all the material passes through the catalyst area. Compared with the case where all the material is in contact with the catalyst in a certain reaction module, this increases the flow efficiency. At the same time, the material comes into contact with the heat-conducting frame 6 multiple times during the flow process, which improves the reaction efficiency and the completeness of the reaction, and significantly reduces the amount of unreacted residue.

[0040] Furthermore, depending on the type of reactants, there are two feed channels 4 in this embodiment: a first feed channel and a second feed channel. Acids enter feed channel 21 through the first feed channel, and alcohols enter through the second feed channel. The catalyst is a solid protic acid catalyst. The acid and alcohol reactants are in contact with the surface of the solid protic acid catalyst, effectively improving the catalyst utilization efficiency. Furthermore, as the materials flow through the catalyst surface in the alternating flow channels 8, proton activation occurs, resulting in a catalytic esterification reaction. Since the catalyst is fixed on the thermally conductive frame, the heat of reaction can be promptly dissipated through the thermally conductive frame 6, the first thermally conductive layer 1, and the second thermally conductive layer 3, avoiding the impact of localized temperature rises on catalyst stability.

[0041] Furthermore, in some embodiments, the heat-conducting medium within the first heat-conducting layer 1 and the second heat-conducting layer 3 is a material with excellent corrosion resistance and thermal conductivity, such as ceramic, glass, or metal. Preferably, the medium within the first heat-conducting layer 1 and the second heat-conducting layer 3 is ceramic. Ceramic is suitable for esterification reaction environments where acidic corrosion exists and can quickly dissipate the heat generated during the reaction to prevent localized high temperatures.

[0042] Furthermore, in some embodiments, the heat-conducting frame 6 is made of a material with excellent corrosion resistance and thermal conductivity, such as ceramic, glass, or metal. Preferably, the heat-conducting frame 6 is made of metal, and the high thermal conductivity of the metal frame allows heat to be transferred along the heat-conducting frame to the heat exchange channel, controlling the temperature gradient in the fixed bed area within a certain range.

[0043] Furthermore, it also includes a separating tank 9 connected to the discharge channel 5. The organic phase outlet of the separating tank 9 is connected to another microchannel reactor 11 with the same structure, forming a microchannel reaction flow. By adjusting the flow rate and reaction temperature, continuous production can be achieved, improving production efficiency and reducing energy consumption. The aqueous phase outlet of the separating tank 9 is connected to an aqueous phase separating tank 10. After the mixed product after the reaction enters the separating tank 9 from the discharge channel 5, it is separated into an organic phase and an aqueous phase under the action of gravity. The organic phase is transported to the feed channel 4 of another microchannel reactor 11 through a circulation pipeline to continuously participate in the esterification reaction; the aqueous phase is transported to a separate aqueous phase separating tank 10 for centralized treatment.

[0044] Furthermore, in some embodiments, the microchannel reactor 11 also includes a pressure pump connected within the material channel 21. The pressure pump forces the material through the material channel 21 and discharges the product through the discharge channel 5. The pressure pump can be a diaphragm pump or a plunger pump, typically installed at the inlet or middle section of the material channel 21. During operation, the pressure pump generates continuous thrust, causing the reactants to be evenly distributed along the flow direction and sequentially pass through the fixed beds of each reaction module. The thrust of the pressure pump overcomes the channel resistance, ensuring that the residence time of the reactants in the fixed bed matches the reaction kinetics requirements, while simultaneously forcibly discharging the product from the discharge channel, preventing product accumulation due to flow resistance.

[0045] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the substance and scope of the present invention. Various modifications made by those skilled in the art to the above embodiments after reading this specification are all within the scope of protection of the present invention.

Claims

1. A microchannel reactor for propionic acid ester synthesis, characterized by, It includes a first heat-conducting layer, a material layer and a second heat-conducting layer arranged from top to bottom. Heat exchange channels extending along the material flow direction are formed in both the first heat-conducting layer and the second heat-conducting layer. Material channels are formed in the material layer. The material channel is provided with a feeding channel at one end and a discharging channel at the other end, and both the feeding channel and the discharging channel avoid the heat exchange channel; Several reaction modules are sequentially arranged in the material channel along the material flow direction. Each reaction module includes at least one heat-conducting frame, and a catalyst is fixed in the heat-conducting frame to form a fixed bed. Flow channels in the same direction as the material flow are formed between the heat-conducting frames of each reaction module, and / or between the heat-conducting frame and the bottom wall of the material channel, and / or between the heat-conducting frame and the top wall of the material channel. The flow channels of two adjacent reaction modules are staggered.

2. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, The thermally conductive frame is a metal mesh structure, and the catalyst is uniformly fixed on the metal mesh structure.

3. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, Each of the reaction modules includes a heat-conducting frame, and the width of the heat-conducting frame is the same as the width of the material channel, so that the flow channel is formed between the heat-conducting frame and the bottom or top wall of the material channel, and the adjacent flow channels are arranged vertically.

4. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, Each of the reaction modules includes a heat-conducting frame, and the height of the heat-conducting frame is the same as the height of the material channel, so that the flow channel is formed between the heat-conducting frame and the sidewall of the material channel, and the adjacent flow channels are arranged in a front-to-back structure.

5. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, The feed channel has two feed channels, namely a first feed channel and a second feed channel. The acid material enters the feed channel through the first feed channel, and the alcohol material enters the feed channel through the second feed channel. The catalyst is a solid protic acid catalyst.

6. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, The medium within the first and second thermally conductive layers includes one or more of ceramics, glass, and metals.

7. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, The material of the heat-conducting frame includes one or more of ceramic, glass, and metal.

8. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, It also includes a separatory tank connected to the discharge channel, wherein the organic phase outlet of the separatory tank is connected to one of the feed channels of another microchannel reactor, and the aqueous phase outlet of the separatory tank is connected to an aqueous phase separatory tank.

9. The microchannel reactor for propionic acid ester synthesis of claim 1, wherein, It also includes a pressure pump connected in the material channel, which pushes the material through the material channel by pressure and discharges the product from the discharge channel.

Images