CN108745224B - Sectional type microreactor device - Google Patents

Abstract

The invention relates to a fluid mixing technology, and provides an absorber (13) which is provided with a fluid inlet and a fluid outlet, is internally filled with an adsorption material, and is externally wound with a heating pipe (54). The invention also proposes a combined device of adsorbers, comprising: a microchannel reactor (11) and an absorber (13) which are connected together, wherein the microchannel reactor (11) is provided with a plurality of microchannels, and a heating pipe is wound on the outer surface of the microchannel reactor (11); the adsorber (13) has a fluid inlet and outlet, is internally filled with an adsorbent material, and has a heating tube (54) wrapped around its outer surface. The invention provides a novel device capable of quickly heating two fluids and carrying out reaction.

Description

A segmented microreactor device

Technical field

The present invention relates to fluid reaction technology, and more specifically, to a segmented microreactor device.

Background technique

Glufosinate is a highly efficient, low-toxic, non-selective (killing) contact organophosphorus herbicide with partial systemic effect. It was first developed by the German company Hoechst. The trade name is Basta. It is a racemic mixture. With the emergence of glyphosate-resistant weeds and the strong toxicity of paraquat, glufosinate-ammonium has received widespread attention. In the synthesis of glufosinate-ammonium, the synthesis of the intermediate methylphosphonic dichloride is the most critical step.

Contents of the invention

In view of the problems in the background technology, the present invention proposes a microreactor and an adsorber for synthesis. The present invention adopts a direct synthesis method, that is, methane gas and phosphorus trichloride are directly reacted at 600 degrees Celsius to produce methylphosphine dichloride. We designed this reactor for the first step. The reaction equation is: CH ₄ +PCl ₃ →HCl+CH ₃ PCl ₂ .

The invention proposes a segmented microreactor device, which includes: a microchannel reactor and an adsorber connected together. The microchannel reactor has a plurality of microchannels, and a heating tube is wound around the surface of the microchannel reactor; The adsorber has a fluid inlet and an outlet, is filled with adsorption material inside, and has a heating tube wrapped around the outside of the adsorber.

Optionally, the segmented microreactor device further includes: a pipeline filter, the pipeline filter is arranged before the microchannel reactor, and the microchannel reactor is arranged before the adsorber.

Optionally, the pipe filter has at least two fluid inlets.

Optionally, the microchannel reactor has mesh holes to filter impurities.

Optionally, the fluid inlet and outlet of the adsorber have filters to block activated carbon.

Optionally, the channel filter, microchannel reactor and adsorber are connected sealingly by threads.

Optionally, the segmented microreactor device includes at least two microreactor groups, and each microreactor group includes: a microchannel reactor and an adsorber connected in sequence.

Optionally, each group includes an inline filter disposed before the microchannel reactor of the group.

Optionally, the microreactor groups are connected sequentially.

Optionally, the adsorber is filled with granular activated carbon.

The beneficial effect of the invention is to provide a new device that can quickly react between two fluids.

Description of the drawings

Figure 1 is a schematic structural diagram of the reaction system of the present invention.

FIG. 2 is a schematic structural diagram of an embodiment of the reaction device in FIG. 1 .

Figure 3 is a cross-sectional view of the reaction device in Figure 2.

Figure 4 is a schematic structural diagram of an embodiment of the reaction device in Figure 1.

FIG. 5 is a cross-sectional view of the reaction device in FIG. 4 .

Figure 6 is a perspective view of the microchannel reactor in Figure 5.

Figure 7 is a schematic structural diagram of the microstructure device in Figure 1.

FIG. 8 is a schematic structural diagram of a part of the microstructure device in FIG. 7 .

FIG. 9 is a schematic structural diagram of a part of the microstructure device in FIG. 7 .

Figure 10 is a schematic structural diagram of the microstructure device and collection container in Figure 1.

Figure 11 is a schematic structural diagram of the reactor, microstructure device and collection container in Figure 1.

Reference signs

First container 1, second container 2, first heat exchanger 3, second heat exchanger 4, reaction device 5, first input pipe 51, second input pipe 52, output pipe 53, compressor 6, microstructure Device 7, first heat exchange section 71, second heat exchange section 72, third heat exchange section 73, heat exchange pipe 74, fluid pipe 75, collection pipe 76, liquid level gauge 8, automatic hydraulic valve 9, collection container 10 , microchannel reactor 11, pipeline filter 12, adsorber 13, heat exchanger 14.

Detailed ways

Embodiments of the present invention are described below with reference to the accompanying drawings, in which like components are designated with like reference numerals. The following embodiments and the technical features in the embodiments can be combined with each other unless there is any conflict.

The present invention is described by taking the production of methylphosphine dichloride, an intermediate product of glufosinate ammonium, as an example, but the present invention is not limited thereto.

As shown in Figure 1, the reaction system of the present invention includes a first container 1. The first container 1 is used to hold a first fluid, such as phosphorus trichloride. A pump is installed at the outlet of the first container 1. The phosphorus trichloride in the container 1 is driven into the pipeline through the pump. The second container 2 is used for a first fluid, such as methane, and is preferably equipped with a flow meter at the outlet of the second container 2 to measure the amount of methane output.

The first container 1 is connected to the first heat exchange section 71 of the microstructure device 7 through a pipe, and the second container 2 is connected to the second heat exchange section 72 of the microstructure device 7 through a pipe. The fluids in the second container 1 and the second container 2 are respectively connected to the second heat exchanger 4 and the first heat exchanger 3 through pipes after heat exchange by the microstructure device 7 .

The first heat exchanger 3 and the second heat exchanger 4 may be resistance heaters. In the first heat exchanger 3 and the second heat exchanger 4, phosphorus trichloride and methane are heated to 600°C respectively, and both are gases. The first heat exchanger 3 and the second heat exchanger 4 are respectively connected to the first input pipe 51 and the second input pipe 52 of the reaction device 5. Phosphorus trichloride and methane react in the reaction device 5 to generate reaction products. Methylphosphine dichloride, along with excess methane. The output pipe 53 of the reaction device 5 is connected to the fluid channel 75 of the microstructure device 7 .

Next, the reaction device 5 will be described in detail. Figure 2 shows a perspective view of one embodiment of the reaction device. Figure 3 shows a cross-sectional view of the reaction apparatus.

The reaction device 5 can be an adsorber 13. The adsorber 13 is a tubular reactor with a diameter of 3 cm. The first input pipe 51 is introduced into the heated methane, and the second input pipe 52 is introduced into the heated phosphorus trichloride. Fluid pipe 53 outputs the reaction product methylphosphine dichloride and excess methane. The adsorber 13 is filled with granular activated carbon. Because HCl gas will be produced during the reaction between methylphosphine dichloride and methane, which will have unnecessary effects on the extraction of the product. The present invention uses high-temperature activated carbon 55 as an acid binding agent to absorb HCl gas. At the same time, the activated carbon will absorb the reactant methane. , which will increase the contact area between methane and phosphorus trichloride, so it can also improve the reaction conversion rate. A heating tube 54 is wrapped around the tube of the adsorber 13 so that the reaction temperature is continuously maintained at 600°C.

Figure 4-5 shows another embodiment of the reaction device. The reaction device is composed of a staggered combination of a tubular adsorber 13 with a diameter of 3cm and a microchannel reactor 11 with a diameter of 1.5cm. It is divided into 4 sections. The first section and The third section is a tubular adsorber 13, and the second and fourth sections are microchannel reactors 11. The tubular adsorber 13 and the microchannel reactor 11 are screwed to each other through nuts. The tubular adsorber 13 is filled with special granular activated carbon, and its structure is the same as the adsorber shown in Figure 2-3. The tubular adsorber 13 is made of two parts twisted together to facilitate regular disassembly. A heating tube is wrapped around the outside of the tube, and heat is efficiently transferred to the reaction fluid through microchannels. Through good temperature control and short reaction time, the yield can be increased.

The microchannel reactor 11 is provided with multiple channels inside. In order to enable the fluid to be fully mixed in the microchannel reactor 11, the circled part in Figure 5 shows a cross-sectional view of the microchannel reactor 11, and Figure 6 shows a perspective view of the microchannel reactor 11. A plurality of microchannels are provided inside the microchannel reactor 11 for rapid heat exchange of fluid. The microchannel reactor 11 can also be wrapped with heating tubes and evenly distributed on the sides of the square microchannel, so that the fluid can start a preliminary reaction.

Optionally, a pipeline filter 12 is installed in front of the microchannel reactor 11, and the pipeline filter 12 has mesh holes on its cross section to filter impurities. The two channels of the pipeline filter 12 are respectively fed into methane and phosphorus trichloride, and the two react to obtain reaction products methylphosphine dichloride and excess methane. HCl gas will be generated during the reaction, which limits the movement of the reaction equilibrium. The high-temperature activated carbon in the tubular adsorber 13 acts as an acid binding agent to adsorb HCl gas, causing the reaction equilibrium to proceed to the right. At the same time, activated carbon will adsorb the reactant methane, which will increase the contact area between methane and phosphorus trichloride, thereby improving the reaction conversion rate. In addition, a filter screen is provided at the product outlet of the tubular adsorber 13 to block the flow of activated carbon.

Next, the microstructure device 7 will be described in detail. Figure 7 shows a schematic structural diagram of the microstructure device 7. Figure 8 shows a partial enlarged view of the microstructure device 7. Figure 9 shows a schematic dimensional view of Figure 8.

The product and excess methane obtained from the adsorber 13 enter the microstructure device 7. The microstructure device 7 can be made by 3D printing technology. The microstructure device 7 is a three-section hollow structure. The heat exchange channels in each section are layered structures. The fluid channels and heat exchange channels are staggered. The fluid channels run through the entire microstructure device 7, as shown in Figure 5.

Specifically, the microstructure device 7 includes a first heat exchange section 71 , a second heat exchange section 72 and a third heat exchange section 73 . The diameter of each segment is approximately 2cm. Each heat exchange section includes heat exchange channels 74 and fluid channels 75 arranged in staggered layers up and down. The heat exchange channels 74 are connected to the first container 1 for inputting phosphorus trichloride and serving as a condensation product. Similarly, the heat exchange channel of the second heat exchange section 72 is connected to the second container 2 for inputting methane to condense the product. The heat exchange channel of the third heat exchange section 73 is used to input cooling liquid to condense the product and further cool the reaction product. In one embodiment, the distance between the sheet-like fluid channels 75 is 500 μm, the heat exchange channel 74 can be a square pipe with a side length of 400 μm, and the distance between the heat exchange channel 74 and the sheet-like fluid channel 75 can be 200 μm. The two heat exchange channels The spacing between 74 can be 400μm. Because there are multiple microchannels in the microstructure device 7, the interfaces connected to each pipeline of the microstructure device 7 can be special one-minute-multiple joints, that is, a thick pipeline fan-shaped diffusion, branching into multiple Dimensional channel.

After the fluid in the first container 1 and the second container 2 reaches the microstructure device 7, it will be heated to close to the reaction temperature, that is, 300°C, by using the first heat exchange section 71 and the second heat exchange section 72 due to heat exchange. . When it reaches the adsorber 13, it is easier to heat to the reaction temperature of 600°C to participate in the reaction. At the same time, the fluid channel 53 output by the adsorber 13 is output through the fluid pipe 75 of the microstructure device 7 , so that the reactant heat of nearly 600°C output from the adsorber 13 is transferred to the heat transferred from the first container 1 and the second container 2 Phosphorus trichloride and methane. As a result, the entire loop forms a closed-loop system, which cools the product while preheating the reactants, saving a lot of heat energy.

The heat exchange part of the microstructure device 7 (the first heat exchange section, the second heat exchange section and the third heat exchange section) has a total length of 10cm, a width and a height of 3cm each. The layered flow channel can be provided with 20 layers, and the heat exchange pipes can be provided 21st floor.

As shown in FIG. 7 , the microstructure device 7 also includes a collection tube 76 , which is connected to the third heat exchange section 73 .

As shown in Figures 1 and 11, the reaction system of the present invention also includes a collection container 10. The collection container 10 is a cavity. The cavity is divided into two parts. The lower part is a cup-shaped structure with a diameter of 15cm and a height of 25cm. Produced by mechanical processing. A liquid level gauge 8 is installed at the bottom of the collection container 10, and a hydraulic valve 9 is installed at the outlet. When the liquid product reaches a certain liquid level in the collection container 10, the hydraulic valve 9 is opened, and the liquid product flows out of the cavity through the pipe. When the liquid level drops below the liquid level gauge 8, the hydraulic valve 9 is closed in order to prevent methane The gas flows out together with the product. The upper half of the collection container 10 is flange-connected with the lower half. The upper half is composed of a plurality of cylindrical heat exchangers 14 . The structure of the heat exchangers 14 is similar to the first heat exchange section 71 of the microstructure device 7 . The heat exchanger is hollow and densely covered with micropores with a diameter of 300 μm and a height of 2 cm. The side of the heat exchanger 14 is also injected with normal temperature cooling liquid to further condense the gas products that are not condensed in time, and to recover excess methane through this structure. It is heated and then output to the first heat exchanger 3 through the compressor 6 to participate in the reaction again.

In an experiment of the present invention, when the mixed gas of phosphorus trichloride gas and methane gas is heated to 600 degrees and the residence time is 5 minutes under normal pressure, the conversion rate of phosphorus trichloride is 100% and the yield is 68%.

Preferably, after the reaction device 5, microstructure device 7, microchannel reactor 11, pipeline filter 12, and adsorber 13 are formed, they are coated using atomic layer deposition technology for anti-corrosion.

The above-described embodiments are only preferred specific implementations of the present invention, and ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims (3)

1. A segmented microreactor device for generating methylphosphine dichloride, characterized in that it includes: It includes at least two groups of microreactor groups connected in sequence, each group of microreactor groups including: a pipeline filter (12), a microchannel reactor (11) and an adsorber (11) that are sequentially connected together and sealingly connected through threads. 13), The two channels of the pipeline filter (12) are fed into methane and phosphorus trichloride respectively, and the cross section of the pipeline filter (12) has mesh holes to filter impurities; The microchannel reactor (11) has a plurality of microchannels, and a heating tube is wound around the outside of the microchannel reactor (11); the adsorber (13) has a fluid inlet and an outlet, and is filled with adsorption material inside. A heating tube (54) is wound around the surface of the adsorber. 2. The segmented microreactor device according to claim 1, characterized in that, The fluid inlet and outlet of the adsorber (13) have filters to block activated carbon. 3. The segmented microreactor device according to claim 1, characterized in that, The adsorber (13) is filled with granular activated carbon.