Integrated thin liquid film microreactor

Abstract

The invention belongs to the technical field of enhanced reaction process, and particularly relates to an integrated thin liquid film microreactor, which comprises a gas introduction assembly, an outlet end of which is communicated with a first end of a tee joint; the outlet end of the liquid leading-in assembly is communicated with the second end of the tee joint, and the liquid leading-in assembly is located under the gas leading-in assembly; one end of the thin liquid film reactor is communicated with the third end of the tee joint; the product collecting assembly is communicated with the other end of the thin liquid film reactor, and the product collecting assembly is used for collecting reaction products in the thin liquid film reactor and discharging the reaction products; the axis of the first end of the tee joint coincides with the axis of the third end, and the axis of the second end of the tee joint is perpendicular to the axes of the first end and the third end. According to the invention, the uniform distribution of materials can be well realized, and the gas-liquid phase flow in flowing can be accurately controlled; the overall space-time yield and selectivity of the reaction can be enhanced. And the device can meet the requirements of continuous, efficient and high-flux synthesis and preparation with a relatively large flow velocity interval, high flow and multiple channels.

Description

Technical Field

[0001] The present invention belongs to the technical field of intensified reaction processes, and particularly relates to an integrated thin liquid film microreactor. Background Art

[0002] In recent years, chemical processes for the preparation of fine organic chemicals have gradually received wide attention. During the batch production of drugs such as those for treating tuberculosis, cancer, and mental diseases, due to factors such as long reaction times, low selectivity, and low yields, the efficient preparation thereof is restricted, resulting in high drug costs. As a key step in the synthesis of these drugs, due to the low heat and mass transfer efficiency and the limitation of the intrinsic reaction kinetics in a conventional reactor, when performing Claisen-Schmidt condensation reaction, Katritzky reaction, and Suzuki coupling reaction, it often takes 10 hours or even longer to achieve a high yield.

[0003] To accelerate the kinetic process of such reactions, it is desired to transfer the conventional macroscopic liquid phase bulk to a thin liquid film for reaction. It is found that partial solvation and molecular orientation ordering at the thin liquid film interface can reduce the reaction energy barrier, showing the unique interface effect of the thin liquid film. Moreover, as the scale of the thin liquid film decreases, this interface effect becomes more prominent. In addition, the reactants at the thin liquid film interface have a faster mass diffusion rate at the mesoscopic scale, and the temperature distribution is more uniform. Therefore, under the combined action of multiple mechanisms of efficient heat and mass transfer and the interface effect, the reaction process is intensified, and the reaction rate and selectivity are greatly improved. However, at present, thin liquid film reactions have not been extended to large-scale industrial production. In current research, the construction of thin liquid films is usually achieved by spray deposition. Although this construction mode is simple, it is impossible to accurately control the morphology and thickness of the thin liquid film, and it is difficult to quantitatively describe the internal relationship between the liquid film thickness and the improvement of reaction efficiency. The mass transfer between the interfacial reaction layer and the viscous sublayer of the conventional thin liquid film only relies on molecular diffusion, and the multi-physical coupling field is not used to control the liquid film morphology to further improve the reaction efficiency. The internal relationship between the flow field structure and the heat and mass transfer mechanism during the reaction process is still unclear. In addition, the experimental scenarios are mostly open environments, and a closed reaction system has not been constructed, making it difficult to achieve large-scale continuous production of target products.

[0004] Therefore, it is necessary to design an integrated thin liquid film microreactor to solve the above problems. Summary of the Invention

[0005] The object of the present invention is to provide an integrated thin liquid film microreactor, which can well achieve uniform distribution of materials and accurately control the gas-liquid phase flow rates in the flow; can enhance the overall space-time yield and selectivity of the reaction. It can be applicable to the continuous high-efficiency high-throughput synthesis and preparation requirements in a relatively large flow rate range, high flow rate, and multi-channel.

[0006] To achieve the above object, the present invention provides the following solution: An integrated thin liquid film microreactor, comprising

[0007] A gas inlet assembly, the outlet end of which is connected to the first end of a tee;

[0008] A liquid inlet assembly, the outlet end of which is connected to the second end of the tee, and the liquid inlet assembly is located directly below the gas inlet assembly;

[0009] A thin liquid film reactor, one end of which is connected to the third end of the tee;

[0010] A product collection assembly, which is connected to the other end of the thin liquid film reactor, and the product collection assembly is used to collect the reaction products in the thin liquid film reactor and discharge the reaction products;

[0011] The axis of the first end of the tee coincides with the axis of the third end, and the axis of the second end of the tee is perpendicular to the axes of the first end and the third end.

[0012] Based on the integrated thin liquid film microreactor of the present invention, the thin liquid film reactor is a continuous bent structure, and the bent structure has an arc transition.

[0013] Based on the integrated thin liquid film microreactor of the present invention, the inner channel inner diameter of the thin liquid film reactor is 0 - 4 mm, and the outer channel inner diameter of the thin liquid film reactor is 0 - 10 mm.

[0014] Based on the integrated thin liquid film microreactor of the present invention, the gas inlet assembly includes a gas phase distributor, the gas phase distributor is located directly above the liquid inlet assembly, the top end of the gas phase distributor is connected to a gas phase inlet, the side wall of the gas phase distributor is fixedly connected with a plurality of gas conduits, the plurality of gas conduits are arranged at equal intervals along the circumferential direction of the side wall of the gas phase distributor, the end of the gas conduit far from the gas phase distributor is connected to the first end of the tee, and a first one-way valve is provided on the gas conduit.

[0015] Based on the integrated thin liquid film microreactor of the present invention, the inner diameter of the gas conduit is 0 - 20 mm, the inner diameter of the gas phase inlet is 0 - 30 mm, and the gas flow rate in the gas phase inlet is 0 - 12 mL / min.

[0016] Based on the integrated thin liquid film microreactor of the present invention, the liquid inlet assembly includes a liquid phase distributor, the liquid phase distributor is located directly below the gas inlet assembly, the top end of the liquid phase distributor is connected to a liquid phase inlet, the side wall of the liquid phase distributor is fixedly connected with a plurality of liquid conduits, the plurality of liquid conduits are arranged at equal intervals along the circumferential direction of the side wall of the liquid phase distributor, the end of the liquid conduit far from the liquid phase distributor is connected to the third end of the tee, and a second one-way valve is provided on the liquid conduit.

[0017] An integrated thin liquid film microreactor based on the present invention, the inner diameter of the liquid conduit is 0 - 10 mm, the inner diameter of the liquid phase inlet is 0 - 15 mm, the liquid flow rate in the liquid phase inlet is 0 - 24 mL / min, and the liquid pressure in the liquid phase distributor is 0 - 100 p.

[0018] An integrated thin liquid film microreactor based on the present invention, the product collection assembly includes a collector, the thin liquid film reactor is communicated with the side wall of the collector, and a product outlet is communicated with the bottom end of the collector.

[0019] An integrated thin liquid film microreactor based on the present invention, the inner diameter of the product outlet is 0 - 30 mm.

[0020] An integrated thin liquid film microreactor based on the present invention, a stop valve is provided at the communication end between the thin liquid film reactor and the collector.

[0021] Compared with the prior art, the present invention has the following advantages and technical effects:

[0022] The present invention ensures that, compared with a conventional macroscopic liquid-phase reactor, in an ultra-thin liquid film reactor, the interfacial reactants have a faster mass diffusion rate at the mesoscopic scale and a more uniform temperature distribution; the provided gas introduction assembly and liquid introduction assembly can not only achieve uniform distribution of materials but also integrally control the gas-phase and liquid-phase rates of the reaction materials, and different numbers of conduits are set according to different situations to achieve large-scale and high-efficiency industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings without creative efforts:

[0024] Figure 1 Schematic diagram of the present invention Figure 1 ;

[0025] Figure 2 Schematic diagram of the present invention Figure 2 ;

[0026] Figure 3 Schematic diagram of a circular thin liquid film;

[0027] Figure 4 Graph of the change in the thickness of the thin liquid film under different gas-liquid velocities;

[0028] Figure 5This is the effect diagram of the present invention for the Claisen-Schmidt reaction.

[0029] Among them, 1. Gas distributor; 2. Gas conduit; 3. First one-way valve; 4. Three-way; 5. Second one-way valve; 6. Liquid conduit; 7. Liquid phase distributor; 8. Liquid phase inlet; 9. Gas phase inlet; 10. Thin liquid film reactor; 11. Stop valve; 12. Collector; 13. Product outlet. Detailed implementation manners

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the drawings and specific implementation manners.

[0032] Refer to Figures 1 to 5 As shown, the present invention provides an integrated thin liquid film microreactor, including a gas introduction component, the outlet end of which is connected to the first end of a three-way 4;

[0033] A liquid introduction component, the outlet end of which is connected to the second end of the three-way 4, and the liquid introduction component is located directly below the gas introduction component;

[0034] A thin liquid film reactor 10, one end of which is connected to the third end of the three-way 4;

[0035] A product collection component, which is connected to the other end of the thin liquid film reactor 10, and the product collection component is used to collect the reaction products in the thin liquid film reactor 10 and discharge the reaction products;

[0036] The axis of the first end of the three-way 4 coincides with the axis of the third end, and the axis of the second end of the three-way 4 is perpendicular to the axes of the first end and the third end.

[0037] Furthermore, the thin liquid film reactor 10 is a continuous bending structure, and the bending structure has an arc transition.

[0038] The ultra-long path of the thin liquid film reactor 10 can enable the reaction to occur fully.

[0039] Furthermore, the inner channel inner diameter of the thin liquid film reactor 10 is 0 - 4 mm, and the outer channel inner diameter of the thin liquid film reactor 10 is 0 - 10 mm.

[0040] Further, the gas introduction component includes a gas distributor 1, which is located directly above the liquid introduction component. The top of the gas distributor 1 is connected to a gas inlet 9, and a plurality of gas conduits 2 are fixedly connected to the side wall of the gas distributor 1. The plurality of gas conduits 2 are arranged at equal intervals along the circumferential direction of the side wall of the gas distributor 1. The end of the gas conduit 2 away from the gas distributor 1 is connected to the first end of a tee 4, and a first check valve 3 is provided on the gas conduit 2.

[0041] Further, the inner diameter of the gas conduit 2 is 0 - 20 mm, the inner diameter of the gas inlet 9 is 0 - 30 mm, and the gas flow rate in the gas inlet 9 is 0 - 12 mL / min.

[0042] Further, the liquid introduction component includes a liquid distributor 7, which is located directly below the gas introduction component. The top of the liquid distributor 7 is connected to a liquid inlet 8, and a plurality of liquid conduits 6 are fixedly connected to the side wall of the liquid distributor 7. The plurality of liquid conduits 6 are arranged at equal intervals along the circumferential direction of the side wall of the liquid distributor 7. The end of the liquid conduit 6 away from the liquid distributor 7 is connected to the third end of the tee 4, and a second check valve 5 is provided on the liquid conduit 6.

[0043] The gas enters the gas distributor 1 through the gas inlet 9, and the solution enters the liquid distributor 7 through the liquid inlet 8. The gas distributor 1 and the liquid distributor 7 are Inlet and Outlet respectively, and there are uniform conduit interfaces on the peripheral wall, which can evenly distribute the gas or liquid into the gas conduits 2 or the liquid conduits 6. The functions of the first check valve 3 and the second check valve 5 are to prevent the gas or liquid from flowing back. Then the gas and the liquid converge in the tee 4, and a thin liquid film is formed due to the inertial force and surface tension of the gas-liquid interface. Placing the liquid distributor 7 below the gas distributor 1 is to avoid forming a stratified flow and better form an annular flow thin liquid film. The gas flow rate in the gas conduit 2 is 0.5 - 50 m / s, and the liquid flow rate in the liquid conduit 6 is 0.0005 - 0.1 m / s.

[0044] Further, the inner diameter of the liquid conduit 6 is 0 - 10 mm, the inner diameter of the liquid inlet 8 is 0 - 15 mm, the liquid flow rate in the liquid inlet 8 is 0 - 24 mL / min, and the liquid pressure in the liquid distributor 7 is 0 - 100 p.

[0045] Further, the product collection component includes a collector 12, and the thin film reactor 10 is connected to the side wall of the collector 12. The bottom end of the collector 12 is connected to a product outlet 13.

[0046] Further, the inner diameter of the product outlet 13 is 0 - 30 mm.

[0047] Further, a stop valve 11 is provided at the connection end between the thin film reactor 10 and the collector 12.

[0048] The working principle of the present invention is as follows:

[0049] Gas and liquid enter the gas conduit 2 and the liquid conduit 6 respectively through the gas-phase inlet 9 and the liquid-phase inlet 8, and converge in the tee 4. Due to the phase interface between the gas phase and the liquid phase, under the action of inertial force and shear force, the gas-liquid phase quickly forms an annular fluid and develops into a thin liquid film state, and then reacts in the thin liquid film reactor 10. After the reaction is completed, the products converge in the collector 12 and flow out.

[0050] In addition, adding a gas-phase distributor 1 and a liquid-phase distributor 7 at the front end of the integrated reactor can not only achieve uniform distribution of materials, but also integrally control the gas-phase and liquid-phase rates of the reaction materials to better control the liquid film thickness, thereby better promoting the occurrence of the reaction.

[0051] In an embodiment of the present invention, in order to explore the thickness of the annular flow ultra-thin liquid film at different gas-liquid phase flow rates in the microchannel, a visualization study on the liquid film thickness of the annular flow in the microchannel under different working conditions was carried out. The Micro-LIF method was used to in-situ observe the flow behavior of the liquid film in the microchannel, stained with a rhodamine B dye solution, and images were captured by a CCD camera. Corresponding laser intensities need to be matched under different experimental conditions. The observation area is located 5 cm away from the inlet to avoid the influence of non-conventional unstable fluctuations of the liquid film due to the inlet effect on the data accuracy. In the visualization experiment, the curvature of the circular tube will cause the captured flow process to be unclear. Therefore, a micro water tank is added to the measurement area of the device, and glycerol is added to the water tank. Since its refractive index is close to that of glass at 1.47, the influence of curvature is greatly eliminated to obtain a clear fluorescence image. The Micro-LIF method can be used to accurately measure the liquid film thickness. The Micro-LIF measurement platform consists of a double-pulse ND:YAG laser, an inverted microscope and a CCD camera.

[0052] In this embodiment, as the gas velocity increases, the shear force at the interface increases, resulting in a decrease in the liquid film thickness. When the gas velocity is 25.8 m / s and the liquid velocity is 0.00368 m / s, the minimum liquid film thickness is only 15 μm, and it increases with the increase of the liquid phase velocity. When the gas velocity is 3.68 m / s and the liquid velocity is 0.01834 m / s, the maximum liquid film thickness is 110 μm. In addition, when the annular flow is in a rippling form, due to the high gas velocity shear, the liquid film thickness is below 50 μm.

[0053] In another embodiment of the present invention, in order to explore the influence of different liquid film thicknesses on the reaction yield, the yield and conversion rate of the Claisen-Schmidt condensation reaction under different liquid film thicknesses were explored.

[0054] Under the action of potassium hydroxide, 1-indanone (IDO) reacts with 4-chlorobenzaldehyde, and a new carbon-carbon bond is formed through aldol condensation, and finally the product (E)-2-(4-chlorobenzylidene)-2,3-dihydro-1H-inden-1-one is obtained. The thin liquid film reaction can accelerate the overall reaction process compared with the conventional bulk phase due to the specific partial solvation effect at the gas-liquid interface. When the thickness of the thin liquid film changes, the ratio of the interface to the bulk phase changes, which has a significant impact on the reaction rate. Since the initial thickness of the liquid film changes with the liquid film flow rate at different gas flow rates, different lengths of channels need to be selected in the experiment to ensure the same reaction residence time. The conversion rate and yield of the reaction are negatively correlated with the liquid film thickness. At the same residence time, the decrease in the liquid film thickness greatly improves the conversion rate and yield of the reaction. Especially when the liquid film thickness decreases from 30 μm to 25 μm, the reaction yield increases by 40%. As the gas flow rate increases, while the liquid film thickness decreases, the reaction process tends to be stable at this time, and the reaction yield also increases. When the initial liquid film thickness decreases to 19 μm, the highest yield can reach 93%.

[0055] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0056] The above-described embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope of the present invention.

Claims

1. An integrated thin liquid film microreactor, characterized in that: include A gas introduction component, the outlet end of which is connected to the first end of a tee (4); A liquid introduction component, the outlet end of which is connected to the second end of the tee (4), and the liquid introduction component is located directly below the gas introduction component; A thin liquid film reactor (10), one end of which is connected to the third end of the tee (4); A product collecting component is connected to the other end of the thin liquid film reactor (10), and the product collecting component is used to collect the reaction products in the thin liquid film reactor (10) and discharge the reaction products; The axis of the first end of the tee (4) coincides with the axis of the third end, and the axis of the second end of the tee (4) is perpendicular to the axes of the first end and the third end.

2. An integrated thin liquid film microreactor according to claim 1, characterized in that: The thin liquid film reactor (10) is a continuous bending structure, and the bending structure is an arc transition.

3. An integrated thin liquid film microreactor according to claim 2, characterized in that: The inner diameter of the inner channel of the thin liquid film reactor (10) is 0-4 mm, and the inner diameter of the outer channel of the thin liquid film reactor (10) is 0-10 mm.

4. The integrated thin liquid film microreactor according to claim 1, characterized in that: The gas introduction component comprises a gas phase distributor (1), the gas phase distributor (1) is located directly above the liquid introduction component, the top of the gas phase distributor (1) is connected to a gas phase inlet (9), the side wall of the gas phase distributor (1) is fixedly connected to a plurality of gas ducts (2), the plurality of gas ducts (2) are arranged at equal intervals along the circumference of the side wall of the gas phase distributor (1), one end of the gas duct (2) away from the gas phase distributor (1) is connected to the first end of the tee (4), and a first one-way valve (3) is arranged on the gas duct (2).

5. An integrated thin liquid film microreactor according to claim 4, characterized in that: The inner diameter of the gas conduit (2) is 0-20 mm, the inner diameter of the gas phase inlet (9) is 0-30 mm, and the gas flow rate in the gas phase inlet (9) is 0-12 mL / min.

6. The integrated thin liquid film microreactor according to claim 1, characterized in that: The liquid introduction component comprises a liquid phase distributor (7), the liquid phase distributor (7) is located directly below the gas introduction component, the top of the liquid phase distributor (7) is connected to a liquid phase inlet (8), the side wall of the liquid phase distributor (7) is fixedly connected to a plurality of liquid conduits (6), the plurality of liquid conduits (6) are arranged at equal intervals along the circumference of the side wall of the liquid phase distributor (7), one end of the liquid conduit (6) away from the liquid phase distributor (7) is connected to the third end of the three-way valve (4), and a second one-way valve (5) is arranged on the liquid conduit (6).

7. An integrated thin liquid film microreactor according to claim 6, characterized in that: The inner diameter of the liquid conduit (6) is 0-10 mm, the inner diameter of the liquid phase inlet (8) is 0-15 mm, the liquid flow rate in the liquid phase inlet (8) is 0-24 mL / min, and the liquid pressure in the liquid phase distributor (7) is 0-100 p.

8. The integrated thin liquid film microreactor according to claim 1, characterized in that: The product collection assembly comprises a collector (12), the thin liquid film reactor (10) is connected to the side wall of the collector (12), and the bottom end of the collector (12) is connected to a product outlet (13).

9. An integrated thin liquid film microreactor according to claim 8, characterized in that: The inner diameter of the product outlet (13) is 0-30 mm.

10. The integrated thin liquid film microreactor according to claim 8, characterized in that: A stop valve (11) is provided at the connecting end between the thin liquid film reactor (10) and the collector (12).

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