CN220026976U - New process preparation system of emamectin benzoate - Google Patents

Abstract

The utility model provides a new process preparation system of emamectin benzoate, which comprises a tubular reactor, wherein the bottom end of the tubular reactor is connected with a raw material mixing tank, one side wall of one side of the raw material mixing tank is connected with a raw material inlet, the other side wall of the raw material mixing tank is connected with a monomethylamine inlet, an external micro-interface unit is arranged outside the raw material mixing tank and is respectively connected with the raw material inlet and the monomethylamine inlet, an internal micro-interface unit is arranged inside the raw material mixing tank and is connected with the external micro-interface unit, and the top end of the raw material mixing tank is connected with the tubular reactor to overflow mixed materials into the tubular reactor for reaction. The utility model adopts a mode of combining a tubular reactor and a micro-interface technology, adopts monomethylamine gas and raw material liquid to mix for imidization reaction, and improves the phase boundary mass transfer area between the raw material and monomethylamine gas, the effective utilization rate of monomethylamine and the reaction rate.

Description

New process preparation system of emamectin benzoate

Technical Field

The utility model belongs to the technical field of emamectin benzoate preparation, and particularly relates to a new process preparation system of emamectin benzoate.

Background

The emamectin benzoate is a novel efficient semisynthetic antibiotic pesticide synthesized from the fermentation product avermectin B1, has the characteristics of super-high efficiency, low toxicity (near-nontoxic preparation), low residue, no pollution and the like, and is widely used for controlling various pests on crops such as vegetables, fruit trees, cotton and the like.

The conventional production process of emamectin benzoate uses avermectin B1 as a starting material, and the emamectin benzoate is obtained through four steps of selective oxidation reaction, selective amination reaction, reduction reaction and salification reaction. At present, the existing emamectin benzoate production process flow needs to add methylene dichloride into a reaction kettle, cool to 0 ℃, add glacial acetic acid, drop 35% of methylamine alcohol solution, reduce the temperature to minus 15 ℃ after the drop is completed, add an oxidation product of avermectin, react for 12 hours, and enter a subsequent reduction crystallization process after passing the central control detection, so as to generate an emamectin benzoate product. Wherein the yield of the emamectin benzoate amide product is about 88 percent.

Aiming at the defects in the prior art, the method comprises the following steps:

(1) The yield of emamectin benzoate amide products is about 88 percent (calculated by the oxidation products of avermectin), after the methylamine alcohol solution is converted into monomethylamine, the effective utilization rate of monomethylamine is about 8 percent, and the consumption of solvents such as methanol, dichloromethane and glacial acetic acid is too high.

(2) The reaction time reaches 12 hours, and the overall reaction efficiency is low.

(3) Each time 1 ton of emamectin benzoate imidite is produced, 9.03 tons of reaction waste liquid is produced in imidization reaction, and the recovery cost is high.

In view of this, the present utility model has been made.

Disclosure of Invention

The utility model aims to provide a new process preparation system of emamectin benzoate, which solves the problems of low effective utilization rate and long reaction time of monomethylamine in the prior art, adopts a tubular reactor to control parameters such as the emamectin benzoate preparation reaction temperature, pressure, flow rate and the like, ensures the stability and consistency of the reaction process, combines a micro-interface technology outside the tubular reactor, fully breaks and disperses raw materials and monomethylamine, improves the phase boundary mass transfer area between the raw materials and monomethylamine gas, improves the effective utilization rate of monomethylamine, and improves the reaction rate.

In order to achieve the above object of the present utility model, the following technical solutions are specifically adopted:

the utility model provides a new process preparation system of emamectin benzoate, which comprises a tubular reactor, wherein the bottom end of the tubular reactor is connected with a raw material mixing tank, one side wall of the raw material mixing tank is connected with a raw material inlet, the other side wall of the raw material mixing tank is connected with a methylamine inlet, an external micro-interface unit is arranged outside the raw material mixing tank and is respectively connected with the raw material inlet and the monomethylamine inlet, an internal micro-interface unit is arranged inside the raw material mixing tank, the internal micro-interface unit is connected with the external micro-interface unit, and the top end of the raw material mixing tank is connected with the tubular reactor to overflow mixed materials into the tubular reactor for reaction.

In the prior art, the emamectin benzoate is prepared by taking avermectin B1 as a starting raw material and carrying out four steps of selective oxidation reaction, selective amination reaction, reduction reaction and salification reaction, but in the step of selective amination reaction in the prior art, dichloromethane, glacial acetic acid, an avermectin oxidation product and a methylamine alcohol solution are generally adopted to prepare the emamectin benzoate amination product, the reaction time is about 12 hours, the reaction energy consumption is increased due to the reaction condition of ultralow temperature at the temperature of minus 15 ℃, and the resource waste is serious due to the overlong reaction time. In addition, the methylamine alcohol solution and the reaction raw materials are subjected to selective amination reaction, the reaction rate is low, the effective utilization rate of monomethylamine is about 8%, and the consumption of solvents such as methanol, dichloromethane and glacial acetic acid is too high.

In order to solve the technical problems, the utility model provides a new process preparation system of emamectin benzoate, which has a simple overall structure, adopts monomethylamine gas to replace methylamine alcohol solution in the prior art, improves the reaction rate and the effective utilization rate of monomethylamine by directly reacting with monomethylamine gas on one hand, does not need methanol solvent on the other hand, saves energy and reduces energy consumption. By arranging an external micro-interface unit outside the raw material mixing tank, monomethylamine gas and raw materials can be crushed and dispersed into micron-sized bubbles and then mixed and contacted, so that the gas-liquid mass transfer area between reactants is increased; through setting up built-in micro-interface unit in raw materials mixing tank inside, mix the stirring to the mixed material that gets into raw materials mixing tank inside, improve reaction efficiency, carry out broken dispersion to the mixed material simultaneously, improve the effective utilization ratio of monomethylamine, reduce the reaction energy consumption.

Preferably, the built-in micro-interface unit is arranged at the bottom end of the raw material mixing tank, the built-in micro-interface unit comprises a first micro-interface generator and a second micro-interface generator, the first micro-interface generator is connected with the external micro-interface unit at one side of the monomethylamine inlet, and the second micro-interface generator is connected with the external micro-interface unit at one side of the raw material inlet.

Preferably, the first micro-interface generator is opposite the outlet of the second micro-interface generator.

Preferably, the external micro-interface unit is symmetrically arranged at two sides of the raw material mixing tank, the external micro-interface unit comprises a third micro-interface generator connected with the raw material inlet and a fourth micro-interface generator connected with the monomethylamine inlet, and the third micro-interface generator is arranged above the fourth micro-interface generator.

Preferably, the third micro-interface generator is connected with the fourth micro-interface generator through a pipeline.

Preferably, a stirring fan blade is arranged in the pipeline and used for circularly stirring the raw material liquid and the monomethylamine gas in the external micro-interface unit.

Preferably, a sleeve is sleeved outside the tubular reactor, and a cooling liquid inlet is formed in the side wall of the sleeve and used for introducing cooling liquid into the sleeve.

Preferably, a circulating pipeline is arranged outside the sleeve, and a heat exchanger is arranged in the middle of the circulating pipeline and used for exchanging heat with the cooling liquid inside.

Before the raw material liquid and the monomethylamine gas enter the tubular reactor, the raw material liquid and the monomethylamine gas are firstly introduced into the raw material mixing tank for mixing and stirring, so that the mixing materials entering the tubular reactor can be ensured to be uniformly mixed, and reactants can be fully contacted and reacted.

The external micro-interface unit is arranged outside the raw material mixing tank, so that monomethylamine gas and raw materials can be crushed and dispersed into micron-sized bubbles and then mixed and contacted, and the gas-liquid mass transfer area between reactants is increased; through setting up built-in micro-interface unit in raw materials mixing tank inside, mix the stirring to the mixed material that gets into raw materials mixing tank inside, improve reaction efficiency, carry out broken dispersion to the mixed material simultaneously, improve the effective utilization ratio of monomethylamine, reduce the reaction energy consumption.

In the utility model, the built-in micro-interface unit is arranged at the bottom of the raw material mixing tank, and is arranged at the bottom, so that the built-in micro-interface unit can stir the liquid of the raw material mixing tank while realizing opposite flushing; specifically, the built-in micro-interface unit comprises a first micro-interface generator and a second micro-interface generator, the first micro-interface generator is opposite to the outlet of the second micro-interface generator, the first micro-interface generator and the outlet of the second micro-interface generator are required to be combined into a whole and are not arranged independently, and the two micro-interface generators are combined into the hybrid micro-interface unit, so that the application effect of the independent micro-interface generator is improved. On the one hand, collision flow can be formed between the first micro-interface generator and the second micro-interface generator, and bubbles are further dispersed and crushed; on the other hand, when the interior of the first micro-interface generator is blocked, the interior of the first micro-interface generator can be flushed through the bubble flow of the second micro-interface generator, so that the blocking is prevented.

In the utility model, the external micro-interface unit comprises a third micro-interface generator and a fourth micro-interface generator, wherein the third micro-interface generator is arranged above the fourth micro-interface generator, the third micro-interface generator is filled with raw material liquid, and the fourth micro-interface generator is filled with monomethylamine gas. The two micro-interface generators are connected through a pipeline, and stirring blades are arranged in the pipeline. When the raw material liquid flows from top to bottom, the stirring fan blade is driven to rotate, and the stirring fan blade rolls the monomethylamine gas and the raw material liquid below the external micro-interface unit back to the upper part, so that the monomethylamine gas content is improved.

And the monomethylamine gas enters a fourth micro-interface generator below the external micro-interface unit, the monomethylamine gas is crushed and dispersed into monomethylamine microbubbles through the fourth micro-interface generator, the monomethylamine microbubbles are mixed with the raw material liquid from bottom to top, the phase boundary mass transfer area of the raw material liquid and the monomethylamine gas is increased, and the monomethylamine gas is sent to a third micro-interface generator above the external micro-interface unit by rotation of the stirring fan blade to perform micro-interface reaction again, so that unreacted monomethylamine gas is crushed and dispersed.

The novel process preparation system is characterized in that a sleeve is sleeved outside the tubular reactor, the outside of the sleeve is connected with a heat exchanger and a circulating pump, and the heat exchanger and the circulating pump are used for carrying out circulating heat exchange on the cooling liquid in the sleeve, so that the temperature of the cooling liquid in the sleeve is ensured to be in accordance with the reaction temperature.

The monomethylamine gas from the top end of the tubular reactor returns to the raw material mixing tank through the pipeline, so that the aim of the arrangement is to improve the recycling effect of tail gas, the monomethylamine outlet from the top end of the tubular reactor is connected with the monomethylamine inlet on the side wall of the raw material mixing tank, and monomethylamine in the tail gas is returned to the raw material mixing tank for continuous reaction, thereby improving the raw material utilization rate and saving the cost.

Those skilled in the art will appreciate that the micro-interface generator used in the present utility model is embodied in prior patents by the present inventors, such as patent application nos. CN201610641119.6, CN201610641251.7, CN201710766435.0, CN106187660, CN105903425A, CN109437390A, CN205833127U and CN 207581700U. The specific product structure and working principle of the micro bubble generator (i.e. the micro interface generator) are described in detail in the prior patent CN201610641119.6, and the application document describes that the micro bubble generator comprises a body and a secondary crushing member, the body is provided with a cavity, an inlet communicated with the cavity is arranged on the body, the opposite first end and the second end of the cavity are both open, wherein the cross-sectional area of the cavity is reduced from the middle part of the cavity to the first end and the second end of the cavity; the secondary crushing member is arranged at least one of the first end and the second end of the cavity, a part of the secondary crushing member is arranged in the cavity, and an annular channel is formed between the secondary crushing member and the through holes with two open ends of the cavity. The micro bubble generator also comprises an air inlet pipe and a liquid inlet pipe. The specific working principle of the structure disclosed in the application document is known as follows: the liquid enters the micro bubble generator tangentially through the liquid inlet pipe, and the gas is rotated and cut at ultrahigh speed to break the gas bubbles into micro bubbles in micron level, so that the mass transfer area between the liquid phase and the gas phase is increased, and the micro bubble generator in the patent belongs to a pneumatic micro interface generator.

In addition, in the prior patent 201610641251.7, it is described that the primary bubble breaker has a circulating liquid inlet, a circulating gas inlet and a gas-liquid mixture outlet, and the secondary bubble breaker communicates the feed inlet with the gas-liquid mixture outlet, which means that the bubble breaker needs to be mixed with gas and liquid, and in addition, as seen in the following figures, the primary bubble breaker mainly uses the circulating liquid as power, so that the primary bubble breaker belongs to a hydraulic micro-interface generator, and the secondary bubble breaker simultaneously introduces the gas-liquid mixture into an elliptical rotating ball for rotation, thereby realizing bubble breaking during rotation, so that the secondary bubble breaker actually belongs to a gas-liquid linkage micro-interface generator. In fact, both the hydraulic type micro-interface generator and the gas-liquid linkage type micro-interface generator belong to a specific form of the micro-interface generator, however, the micro-interface generator adopted by the utility model is not limited to the above-mentioned forms, and the specific structure of the bubble breaker described in the prior patent is only one form which can be adopted by the micro-interface generator of the utility model.

Furthermore, the prior patent 201710766435.0 states that the principle of the bubble breaker is that the high-speed jet flows are used for achieving the mutual collision of gases, and also states that the bubble breaker can be used for a micro-interface strengthening reactor, and the correlation between the bubble breaker and the micro-interface generator is verified; in addition, in the prior patent CN106187660, there are also related descriptions about specific structures of bubble breakers, specifically, see paragraphs [0031] to [0041] in the specification, and the accompanying drawings, which describe the specific working principle of the bubble breaker S-2 in detail, wherein the top of the bubble breaker is a liquid phase inlet, the side is a gas phase inlet, and the entrainment power is provided by the liquid phase entering from the top, so as to achieve the effect of breaking into ultrafine bubbles.

Since the micro-interface generator was just developed in the early stage of the prior patent application, the micro-interface generator is named as a micro-bubble generator (CN 201610641119.6), a bubble breaker (201710766435.0) and the like in the early stage, and with the continuous technological improvement, the micro-interface generator is named as a micro-interface generator in the later stage, and the micro-interface generator is equivalent to the prior micro-bubble generator, the bubble breaker and the like in the present utility model, but the names are different. In summary, the micro-interface generator of the present utility model belongs to the prior art.

Compared with the prior art, the utility model has the beneficial effects that:

(1) The new process preparation system of the emamectin benzoate adopts the built-in micro-interface unit and the external micro-interface unit to be matched, the raw material liquid and the monomethylamine gas are crushed and dispersed through the external micro-interface unit, the phase boundary area of the monomethylamine gas and the raw material liquid is increased, the reaction efficiency is improved, the opposite flushing is realized through the built-in micro-interface unit, meanwhile, the mixed materials in the raw material mixing tank are stirred, the reaction time is reduced to 5-8 hours, the reaction temperature is increased to minus 10-0 ℃, and the effective utilization rate of monomethylamine is increased to more than 60%.

(2) Through setting up tubular reactor, compact structure saves time, through controlling parameters such as tubular reactor reaction temperature, pressure and velocity of flow, guarantees the stability and the uniformity of reaction process, realizes continuous production to improve production efficiency.

(3) The sleeve barrel is arranged outside the tubular reactor and is matched with the heat exchanger for use, so that a proper reaction temperature is provided for the tubular reactor, and the reaction rate is improved.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the utility model. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

FIG. 1 is a schematic diagram of a new process preparation system for emamectin benzoate according to embodiment 1 of the present utility model;

fig. 2 is a schematic structural diagram of a new process preparation system for emamectin benzoate provided in embodiment 4 of the present utility model.

Wherein:

1-a tubular reactor; 2-a raw material mixing tank;

3-raw material inlet; 4-monomethylamine inlet;

5-arranging a micro-interface unit; 501-a first micro-interface generator;

502-a second micro-interface generator; 6-an external micro-interface unit;

601-a third micro-interface generator; 602-a fourth micro-interface generator;

603-stirring fan blades; 7-sleeving a barrel;

8-a cooling liquid inlet; 9-a heat exchanger;

a 10-monomethylamine storage tank; 11-monomethylamine outlet.

Detailed Description

The technical solution of the present utility model will be clearly and completely described below with reference to the accompanying drawings and detailed description, but it will be understood by those skilled in the art that the examples described below are some, but not all, examples of the present utility model, and are intended to be illustrative of the present utility model only and should not be construed as limiting the scope of the present utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

In order to more clearly illustrate the technical scheme of the utility model, the following description is given by way of specific examples.

Example 1

Referring to fig. 1, the new process preparation system for emamectin benzoate according to the embodiment of the utility model comprises a tubular reactor 1, wherein the bottom end of the tubular reactor 1 is connected with a raw material mixing tank 2, one side wall of the raw material mixing tank 2 is connected with a raw material inlet 3, the other side wall of the raw material mixing tank 2 is connected with a monomethylamine inlet 4, an external micro-interface unit 6 is arranged outside the raw material mixing tank 2 and is respectively connected with the raw material inlet 3 and the monomethylamine inlet 4, an internal micro-interface unit 5 is arranged inside the raw material mixing tank 2, the internal micro-interface unit 5 is connected with the external micro-interface unit 6, and the top end of the raw material mixing tank 2 is connected with the tubular reactor 1 so as to overflow mixed materials into the tubular reactor 1 for reaction.

Specifically, the process flow based on the utility model is to mix raw materials of avermectin oxidation product, methylene dichloride solution and glacial acetic acid solution with monomethylamine gas to carry out imidization reaction, the reaction raw materials of the utility model comprise monomethylamine gas, so the tubular reactor 1 is adopted, the traditional reaction kettle can quickly move upwards after introducing monomethylamine gas and raw material solution due to smaller density of monomethylamine gas, so the contact time between monomethylamine gas and raw material solution is shortened, the effective utilization rate of monomethylamine gas is lower, the tubular reactor 1 is adopted, on one hand, high-efficiency and stable reaction conditions can be ensured, and on the other hand, the tubular reactor 1 has smaller volume and larger surface area, so the monomethylamine gas and the raw material solution can be contacted and reacted more quickly, and the reaction rate is improved. Preferably, the tubular reactor 1 of the present utility model is a spiral ascending tubular reactor, and the raw material liquid and the monomethylamine gas are mixed and conveyed upward by using a rotating spiral structure, so that the monomethylamine gas and the raw material liquid flow upward simultaneously, the reactants can be fully contacted and reacted, and the effective utilization rate of monomethylamine is improved, which is not suggested in the prior art on the premise of taking the monomethylamine alcohol liquid as the raw material.

Specifically, the bottom end of the tubular reactor 1 is connected with the raw material mixing tank 2, a built-in micro-interface unit 5 is arranged in the raw material mixing tank 2, and the built-in micro-interface unit 5 breaks and disperses the mixed materials entering the tubular reactor 1, so that the phase boundary area of the mixed materials in the tubular reactor 1 is increased, and meanwhile, the mixed materials are fully contacted in the tubular reactor 1, and the reaction yield is improved.

Specifically, the built-in micro-interface unit 5 is arranged at the bottom of the raw material mixing tank 2, the built-in micro-interface unit 5 comprises a first micro-interface generator 501 and a second micro-interface generator 502, the first micro-interface generator 501 is connected with the external micro-interface unit 6 at one side of the monomethylamine inlet 4, and the second micro-interface generator 502 is connected with the external micro-interface unit 6 at one side of the raw material inlet 3.

In this embodiment, the first micro-interface generator 501 and the second micro-interface generator 502 are disposed on the same straight line, the first micro-interface generator 501 is opposite to the outlet of the second micro-interface generator 502, and the monomethylamine gas raw material liquid in the first micro-interface generator 501 and the monomethylamine gas and raw material liquid in the second micro-interface generator 502 realize opposite flushing, so as to increase the phase boundary mass transfer area, and simultaneously stir the mixed materials in the raw material mixing tank 2.

The external micro-interface unit 6 is symmetrically arranged on two sides of the raw material mixing tank 2, the external micro-interface unit 6 comprises a third micro-interface generator 601 connected with the raw material inlet 3 and a fourth micro-interface generator 602 connected with the monomethylamine inlet 4, and the third micro-interface generator 601 is arranged above the fourth micro-interface generator 602. Preferably, the third micro-interface generator 601 and the fourth micro-interface generator 602 are connected by a pipeline. The stirring fan blades 603 are arranged in the pipeline and are used for circularly stirring the raw material liquid and the monomethylamine gas in the external micro-interface unit 6.

The stirring fan blade 603 is arranged because the stirring fan blade 603 is matched with the external micro-interface unit 6, the raw material for preparing the emamectin benzoate is monomethylamine gas, the density of the monomethylamine gas is smaller, the fourth micro-interface generator 602 connected with the monomethylamine inlet 4 in the external micro-interface unit 6 is arranged below, so that the monomethylamine gas is crushed and dispersed through the fourth micro-interface generator 602 to form monomethylamine microbubbles, and then the monomethylamine microbubbles are mixed with the liquid raw material from bottom to top, so that the phase boundary area of the liquid raw material and the monomethylamine gas is increased, the stirring fan blade 603 rotates to send the monomethylamine microbubbles to the third micro-interface generator 601 above the external micro-interface unit 6 for carrying out micro-interface reaction again, and unreacted monomethylamine gas is crushed and dispersed. In the prior art, the methylamine alcohol liquid is used as a reaction raw material, and after entering the micro-interface system, the methylamine alcohol liquid is liquid, so that the methylamine alcohol liquid has relatively heavy self weight after being crushed and dispersed, and is difficult to be transmitted to the micro-interface generator above for reaction through the stirring fan blade 603, and the circulation stirring is not needed naturally. Therefore, the preparation system of the utility model is characterized in that the stirring fan blades are specifically arranged for the monomethylamine gas serving as a reaction raw material of the utility model, so that the effective utilization rate of monomethylamine in the prior art is naturally not higher than that of monomethylamine gas of the utility model.

In the embodiment, a sleeve 7 is sleeved outside the tubular reactor 1, and a cooling liquid inlet 8 is arranged on the side wall of the sleeve 7 and used for introducing cooling liquid into the sleeve 7, so that the reaction is in a low-temperature environment.

The outside of the sleeve 7 is provided with a circulating pipeline, a heat exchanger 9 is arranged in the middle of the circulating pipeline and used for exchanging heat with the cooling liquid in the sleeve, and a circulating pump is also arranged on the circulating pipeline and used for providing power for the circulating liquid;

the side wall of the sleeve 7 is also provided with a cooling liquid inlet 8 for introducing cooling liquid into the sleeve 7.

In the embodiment of the present utility model, the monomethylamine inlet 4 is connected to the monomethylamine storage tank 10 and the monomethylamine outlet 11 at the top of the tubular reactor 1 by a pipe to recover unreacted monomethylamine gas in the tubular reactor 1.

Specifically, a circulating pump is further arranged between the raw material inlet 3 and the raw material mixing tank 2 to provide power for the liquid-phase raw materials.

It is to be understood that the number of the micro-interface generators in the above embodiment is not limited, and additional micro-interface generators may be added to increase the dispersion and mass transfer effects.

When the preparation system is specifically used for reaction, raw materials of avermectin oxidation products, methylene dichloride solution, glacial acetic acid solution and monomethylamine gas in a monomethylamine storage tank 10 are crushed and dispersed through an external micro-interface unit 6, and then are introduced into a first micro-interface generator 501 and a second micro-interface generator 502 in a raw material mixing tank 2 for secondary crushing and dispersion; the mixed material formed after the first micro-interface generator 501 and the second micro-interface generator 502 are opposite-flushed enters the tubular reactor 1 in an overflow mode to carry out imidization reaction, the reaction temperature is-5 ℃, and the reaction product is subjected to subsequent reduction crystallization to generate emamectin benzoate.

Example 2

This example differs from example 1 only in the reaction temperature, which is 0 ℃.

Example 3

This example differs from example 1 only in the reaction temperature, which is-10 ℃.

Example 4

The difference between this embodiment and embodiment 3 is that the outlet of the first micro-interface generator and the outlet of the second micro-interface generator of the built-in micro-interface unit are not on the same line, as shown in fig. 2.

Comparative example 1

The difference between this embodiment and embodiment 3 is that no built-in micro interface unit is provided.

Comparative example 2

The difference between this embodiment and embodiment 3 is that no external micro-interface unit is provided.

Comparative example 3

In the method, the prior art is adopted, methylene dichloride is directly added into a reaction kettle, the temperature is reduced to 0 ℃, glacial acetic acid is added, 35% of methylamine alcohol solution is dropwise added, after the dropwise addition is finished, the temperature is reduced to minus 15 ℃, an oxidation product of abamectin is added for imidization, and the reaction product enters a subsequent reduction crystallization process to generate a emamectin benzoate product.

Experimental example 1

The preparation systems of examples 1-4 and comparative example 1 were used to prepare emamectin benzoate, respectively, wherein: the feed amount of oxidation products of avermectin is 1026kg/batch, and the feed amount of monomethylamine is 66kg/batch and 28.3m ³ Batch, methylene chloride feed 6800kg/batch, reaction liquid circulation 20m ³ And/h, the reaction pressure is 0.1MPa. The reaction results are shown in the following table:

TABLE 1

As can be seen from table 1, the reaction temperature of the preparation system of the present embodiment is obviously higher than that of the preparation of emamectin benzoate in the prior art, and the reaction time is obviously shortened, so that the preparation system of the present embodiment still has good raw material conversion rate and product yield, and meanwhile, the effective utilization rate of monomethylamine is obviously improved, so that the reaction energy consumption of the preparation system of the present embodiment is low, and the preparation effect is good.

The effective utilization rate of monomethylamine in comparative example 1 is lower than that in example 3, because comparative example 1 is not provided with a built-in micro-interface unit, and the monomethylamine cannot be crushed and dispersed in the raw material mixing tank and cannot stir the mixed materials in the raw material mixing tank, and therefore the effective utilization rate of monomethylamine is improved by arranging the micro-interface generators in the raw material mixing tank.

In a word, compared with the prior art, the new process for preparing the emamectin benzoate has the advantages of easiness in realization of reaction temperature, short reaction time, high raw material conversion rate and high product yield, and is worthy of wide popularization and application.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the utility model.

Claims (8)

1. The new process preparation system of emamectin benzoate comprises a tubular reactor, wherein the bottom end of the tubular reactor is connected with a raw material mixing tank, one side wall of the raw material mixing tank is connected with a raw material inlet, the other side wall of the raw material mixing tank is connected with a methylamine inlet, an external micro-interface unit is arranged outside the raw material mixing tank and is connected with the raw material inlet and the monomethylamine inlet respectively, an internal micro-interface unit is arranged inside the raw material mixing tank and is connected with the external micro-interface unit, and the top end of the raw material mixing tank is connected with the tubular reactor to overflow mixed materials into the tubular reactor for reaction.

2. The new process preparation system of emamectin benzoate according to claim 1, wherein the built-in micro-interface unit is arranged at the bottom of the raw material mixing tank, the built-in micro-interface unit comprises a first micro-interface generator and a second micro-interface generator, the first micro-interface generator is connected with the external micro-interface unit at the side of the monomethylamine inlet, and the second micro-interface generator is connected with the external micro-interface unit at the side of the raw material inlet.

3. The new process preparation system for emamectin benzoate according to claim 2, wherein said first micro-interface generator is opposite to the outlet of said second micro-interface generator.

4. The new process preparation system of emamectin benzoate according to claim 1, wherein the external micro-interface units are symmetrically arranged at two sides of the raw material mixing tank, the external micro-interface units comprise a third micro-interface generator connected with a raw material inlet and a fourth micro-interface generator connected with a monomethylamine inlet, and the third micro-interface generator is arranged above the fourth micro-interface generator.

5. The new process preparation system for emamectin benzoate according to claim 4, wherein the third micro-interface generator is connected with the fourth micro-interface generator through a pipeline.

6. The new process preparation system of emamectin benzoate according to claim 5, wherein the stirring fan blades are arranged in the pipeline to stir the raw material liquid and monomethylamine gas in the external micro interface unit in a circulating way.

7. The new process preparation system of emamectin benzoate according to claim 1, wherein a sleeve is sleeved outside the tubular reactor, and a cooling liquid inlet is arranged on the side wall of the sleeve for introducing cooling liquid into the sleeve.

8. The new process preparation system of emamectin benzoate according to claim 7, wherein a circulating pipeline is arranged outside the sleeve, and a heat exchanger is arranged in the middle of the circulating pipeline for exchanging heat with the cooling liquid inside.