Apparatus for preparing neotame

Abstract

The utility model relates to compound preparation technical field, concretely relates to a preparation device of neotame, the preparation device includes: reaction kettle and precooling structure, precooling structure is connected with reaction kettle to pass in the reaction kettle after precooling structure precooling of alkaline solution, precooling structure includes first feed port, second feed port, first discharge port, second discharge port and cooling pipeline, second discharge port is connected with the feed port of reaction kettle, and one end of cooling pipeline is connected with first feed port to pass in cooling medium, and the other end of cooling pipeline is connected with first discharge port to discharge cooling medium, and alkaline solution enters precooling structure from second feed port and passes in the reaction kettle from second discharge port after heat exchange cooling with cooling pipeline, to make the temperature of reaction kettle reduce to first predetermined temperature.

Description

Technical Field

[0001] This utility model relates to the field of compound preparation technology, specifically to a neotame preparation apparatus. Background Technology

[0002] Neotame is a synthetic sweetener with a high sweetness level, 7,000-13,000 times sweeter than sucrose, and boasts advantages such as low calories, high safety, and high chemical stability. Currently, the synthesis of neotame commonly involves reacting 3,3-dimethylbutyraldehyde with aspartame under palladium-carbon catalysis. After the reaction, vacuum distillation is typically used to separate and purify the product. However, after vacuum distillation, the temperature inside the reaction vessel is high, generally between 50-60°C. Under these conditions, directly adding a weak alkali to the reaction vessel for subsequent processing can lead to a series of side reactions. These side reactions not only reduce the yield of neotame, causing waste of raw materials and increased production costs, but also affect the purity and quality of the product.

[0003] In some scenarios, to reduce side reactions and improve the yield and quality of neotame, it is usually necessary to lower the temperature inside the reactor to 20-30°C before adding the weak alkali. Traditional cooling methods primarily rely on the reactor's own cooling system, such as jacketed cooling. However, these methods have significant limitations. Firstly, the reactor's cooling system is relatively slow, especially when the reactor is large; cooling from 50-60°C to 20-30°C takes a considerable amount of time, undoubtedly increasing the overall production cycle and reducing neotame production efficiency. Secondly, the prolonged cooling process can lead to slow side reactions within the reactor, affecting the product quality and yield of neotame. Utility Model Content

[0004] To address the technical problems of low production efficiency, product quality, and yield of neotame, the purpose of this invention is to provide a neotame preparation apparatus, the specific technical solution of which is as follows: In a first aspect, this utility model discloses a neotame preparation apparatus, comprising: a reaction vessel 10 and a precooling structure 20. The precooling structure 20 is connected to the reaction vessel 10 to precool an alkaline solution before introducing it into the reaction vessel 10. The precooling structure 20 includes a first inlet 2011, a second inlet 2012, a first outlet 2013, a second outlet 2014, and a cooling pipe 2010. The second outlet 2014 is connected to the inlet of the reaction vessel 10. One end of the cooling pipe 2010 is connected to the first inlet 2011 to introduce a cooling medium, and the other end of the cooling pipe 2010 is connected to the first outlet 2013 to discharge the cooling medium. The alkaline solution enters the precooling structure 20 from the second inlet 2014 and is cooled by heat exchange with the cooling pipe 2010 before being introduced into the reaction vessel 10 from the second outlet 2014, thereby reducing the temperature of the reaction vessel 10 to a first predetermined temperature.

[0005] Optionally, the reactor 10 includes a jacketed cooling structure to cool the reactor 10 to a second predetermined temperature; when the temperature of the reactor 10 drops to the second predetermined temperature, an alkaline solution is introduced into the reactor 10 from the second outlet to lower the temperature of the reactor 10 to a first predetermined temperature, which is lower than the second predetermined temperature.

[0006] Optionally, the first predetermined temperature is 20℃-30℃, and the second predetermined temperature is 40℃-50℃.

[0007] Optionally, the precooling structure 20 includes a high-level tank 201, which is located above the reactor 10. The inner cavity of the high-level tank 201 is provided with a spiral cooling pipe 2010. One end of the cooling pipe 2010 is located at the top of the high-level tank 201, and the other end of the cooling pipe 2010 is located at the bottom of the high-level tank 201. A first feed inlet 2011 and a second feed inlet 2012 are provided at the top of the tank, and the first feed inlet 2011 is adjacent to one end of the cooling pipe 2010. A first discharge outlet 2013 and a second discharge outlet 2014 are provided at the bottom of the tank, and the first discharge outlet 2013 is adjacent to the other end of the cooling pipe 2010.

[0008] Optionally, the precooling structure 20 also includes a condenser 202, with a first inlet and a second outlet 2014 connected to the condenser 202. A cooling medium is introduced into the second inlet of the condenser 202 to further cool the alkaline solution. The outlet of the condenser 202 is connected to the inlet of the reactor 10.

[0009] Optionally, the precooling structure 20 also includes a condenser 202. A cooling medium is introduced into the second inlet of the condenser 202, and an alkaline solution is introduced into the first inlet of the condenser 202 to cool the alkaline solution. The outlet of the condenser 202 is connected to the second inlet 2012 of the high-level tank 201 so that the cooled alkaline solution is introduced into the high-level tank 201 for further cooling, and then introduced into the reactor 10 through the second outlet 2014 of the high-level tank 201.

[0010] Optionally, the precooling structure 20 also includes a first regulating valve 203, which is located on the connecting pipe between the second discharge port 2014 of the high-level tank 201 and the first feed port of the condenser 202 to regulate the flow rate of the alkaline solution entering the condenser 202.

[0011] Optionally, the precooling structure 20 also includes a second regulating valve 204, which is located on the connecting pipe between the outlet of the condenser 202 and the inlet of the reactor 10 to regulate the flow rate of the alkaline solution entering the reactor 10.

[0012] Optionally, condenser 202 is a horizontal shell-and-tube condenser.

[0013] Optionally, the cooling pipe 2010 is a polyethylene pipe.

[0014] The preparation apparatus provided in this embodiment of the invention features a pre-cooling structure connected to the reaction vessel. This structure allows the alkaline solution to be pre-cooled via cooling pipes. The pre-cooling process is completed through heat exchange between the cooling pipes and the alkaline solution, pre-consuming some of the heat from the alkaline solution and reducing the cooling load required to lower the temperature to the first predetermined temperature after the reaction vessel starts up, thus reducing the energy consumption of the equipment. Furthermore, since the alkaline solution is pre-cooled before entering the reaction vessel, there is no need to wait for an excessively long cooling process. The pre-cooled alkaline solution, once added to the reaction vessel, quickly brings the vessel to the first predetermined temperature and into a stable reaction stage, effectively shortening the production cycle and improving the production efficiency of neotame. By stably controlling the reaction vessel temperature to the first predetermined temperature and shortening the time required for the reaction vessel to reach that temperature, material decomposition, volatilization, or other unsafe reactions caused by excessively high temperatures or prolonged cooling times can be effectively avoided, providing a more reliable safety guarantee for industrial production. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the first neotame preparation apparatus disclosed in the embodiment of this utility model.

[0016] Figure 2 This is a schematic diagram of the second neotame preparation apparatus disclosed in this embodiment of the present invention.

[0017] Figure 3This is a schematic diagram of the structure of a high-level groove disclosed in an embodiment of the present utility model.

[0018] In the figure: reactor 10, precooling structure 20, high-level tank 201, cooling pipe 2010, first feed inlet 2011, second feed inlet 2012, first discharge outlet 2013, second discharge outlet 2014, condenser 202, first regulating valve 203, second regulating valve 204. Detailed Implementation

[0019] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a neotame preparation apparatus according to this utility model. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The specific details of a neotame preparation apparatus provided by this invention are described below with reference to the accompanying drawings.

[0021] like Figures 1 to 3 As shown, Figure 1 This is a schematic diagram of the structure of the first neotame preparation apparatus disclosed in this utility model embodiment. Figure 2 This is a schematic diagram of the structure of the second neotame preparation apparatus disclosed in this embodiment of the present invention. Figure 3 This is a schematic diagram of a high-level tank according to an embodiment of the present invention. The preparation device includes a reactor 10 and a precooling structure 20. The precooling structure 20 is connected to the reactor 10 to precool an alkaline solution before it is introduced into the reactor 10. The precooling structure 20 includes a first inlet 2011, a second inlet 2012, a first outlet 2013, a second outlet 2014, and a cooling pipe 2010. The second outlet 2014 is connected to the inlet of the reactor 10. One end of the cooling pipe 2010 is connected to the first inlet 2011 to introduce a cooling medium, and the other end of the cooling pipe is connected to the first outlet 2013 to discharge the cooling medium. The alkaline solution enters the precooling structure from the second inlet 2012 and is cooled by heat exchange with the cooling pipe 2010 before being introduced into the reactor 10 from the second outlet 2014, thereby reducing the temperature of the reactor 10 to a first predetermined temperature.

[0022] Specifically, 3,3-dimethylbutyraldehyde and aspartame react in reactor 10 under palladium-on-carbon catalysis. After the reaction, the products are separated and purified by vacuum distillation. After vacuum distillation, the temperature inside the reactor is relatively high, typically between 50°C and 60°C. To reduce side reactions, the temperature inside the reactor is usually lowered to 20°C-30°C before the weak alkali is added dropwise. To shorten the cooling time of the reactor, this invention employs a pre-cooling structure to cool the alkaline solution. After the cooled alkaline solution is added to the reactor, the temperature inside the reactor drops rapidly, thus shortening the cooling time. The alkaline solution can be a sodium bicarbonate solution.

[0023] Optionally, as an optional embodiment of this utility model, the precooling structure 20 includes a high-level tank 201, which is disposed above the reactor 10. The inner cavity of the high-level tank 201 is provided with a spiral cooling pipe 2010. One end of the cooling pipe 2010 is located at the top of the tank body of the high-level tank 201, and the other end of the cooling pipe 2010 is located at the bottom of the tank body of the high-level tank 201. A first feed inlet 2011 and a second feed inlet 2012 are provided at the top of the tank body, and the first feed inlet 2011 is adjacent to one end of the cooling pipe 2010. A first discharge outlet 2013 and a second discharge outlet 2014 are provided at the bottom of the tank body, and the first discharge outlet 2013 is adjacent to the other end of the cooling pipe 2010.

[0024] Specifically, the elevated tank 201 is located above the reactor 10, and its main function is to provide a closed space for the pre-cooling process of the alkaline solution. By utilizing the height difference between itself and the reactor, the alkaline solution is naturally transported to the reactor by gravity, reducing the use of additional power equipment and lowering energy consumption and equipment failure rate. The spiral cooling pipe is a key component for heat exchange cooling, coiled inside the cavity of the elevated tank 201. One end connects to the top of the elevated tank, and the other end extends to the bottom of the tank. This spiral structure design maximizes the contact area between the pipe and the alkaline solution within a limited space. Compared to straight pipes or other shapes, the spiral structure extends the heat exchange path between the cooling medium and the solution, allowing for more thorough heat exchange between the cooling medium and the solution during flow, significantly improving cooling efficiency. The first inlet 2011 is located at the top of the elevated tank 201 and is adjacent to the top of the cooling pipe 2010. Its main function is to introduce a cooling medium (such as cold water, coolant, etc.) into the cooling pipe 2010. The second inlet 2012 is also located at the top of the high-level tank 201, serving as the entrance for the alkaline solution into the pre-cooling structure 20. After entering the high-level tank through this inlet, the alkaline solution flows downwards along the inner cavity under gravity, making full contact with the spiral cooling pipes during the process. Heat exchange is achieved through heat conduction, completing the pre-cooling process. The first outlet 2013 is located at the bottom of the high-level tank and is adjacent to the bottom end of the cooling pipe 2010, used to discharge the cooling medium after heat exchange. The second outlet 2014 is located at the bottom of the high-level tank and serves as the outlet for the pre-cooled alkaline solution to enter the reactor. After sufficient heat exchange with the cooling pipe 2010, the alkaline solution, with its temperature reduced to the target range, flows out from this outlet and naturally flows into the reactor due to the height difference between the high-level tank and the reactor, providing the reactor with raw materials at the required temperature and ensuring that the temperature inside the reactor can be quickly stabilized at the first predetermined temperature.

[0025] Thus, the cooling pipe 2010, with one end located at the top of the high-level tank 201 and the other end at the bottom, forms a forward or reverse flow path with the first inlet 2011 (top) and the first outlet 2013 (bottom). When the cooling medium enters the cooling pipe from the top inlet, it flows gradually from top to bottom along the spiral pipe. During this process, it can form sufficient reverse or forward contact with the alkaline solution flowing from the second inlet (top) to the second outlet (bottom) in the high-level tank 201. This coordination of flow directions maximizes the heat exchange time between the two, allowing the cooling medium to continuously exchange heat with the alkaline solution at different temperature stages as it gradually cools down from its initial high temperature, further improving heat exchange efficiency and avoiding the problem of insufficient local heat exchange.

[0026] Optionally, as an optional embodiment of the present invention, the precooling structure 20 further includes a condenser 202, the first inlet of the condenser 202 is connected to the second outlet, the second inlet of the condenser 202 is circulated with a cooling medium to cool the alkaline solution again, and the outlet of the condenser 202 is connected to the inlet of the reaction vessel 10.

[0027] Specifically, condenser 202 can further cool the alkaline solution after it has been cooled in the high-level tank. The first inlet of the condenser is connected to the second outlet of the high-level tank in the pre-cooling structure, and its function is to receive the alkaline solution after pre-cooling in the high-level tank. The second inlet of the condenser is mainly used to introduce a cooling medium (such as low-temperature brine, coolant, etc.). The cooling medium enters the heat exchange channel inside the condenser through this inlet and exchanges heat with the alkaline solution entering from the first inlet of the condenser, thereby achieving a further cooling of the alkaline solution. The outlet of the condenser is located at the bottom of the condenser and is connected to the inlet of the reactor. Its function is to transport the alkaline solution, which has been further cooled and reached the temperature required for the reaction, into the reactor. Thus, the alkaline solution pre-cooled in the high-level tank may not reach the ideal temperature due to factors such as fluctuations in the feed rate and changes in ambient temperature. The secondary cooling of the condenser can effectively compensate for this deficiency, accurately controlling the temperature of the alkaline solution within a range closer to the first predetermined temperature, providing a more precise feed temperature to the reactor.

[0028] Optionally, as an optional embodiment of this utility model, the precooling structure 20 further includes a condenser 202. A cooling medium is introduced into the second inlet of the condenser 202, and an alkaline solution is introduced into the first inlet of the condenser 202 to cool the alkaline solution. The outlet of the condenser 202 is connected to the second inlet of the high-level tank 201 so that the cooled alkaline solution is introduced into the high-level tank 201 for further cooling, and then introduced into the reactor 10 through the second outlet of the high-level tank 201.

[0029] Specifically, the second inlet of condenser 202 serves as the inlet for the cooling medium, responsible for introducing the low-temperature cooling medium (such as coolant, low-temperature gas, etc.) into the heat exchange chamber inside the condenser. After entering through this inlet, the cooling medium undergoes efficient heat exchange with the alkaline solution inside the condenser, providing a cold source for the initial cooling of the alkaline solution. The first inlet of condenser 202 is the initial inlet for the alkaline solution to enter the pre-cooling structure. The uncooled alkaline solution flows into the condenser through this inlet, completing the first heat exchange with the cooling medium inside the condenser, achieving initial cooling. The outlet of condenser 202 connects to the second inlet of the high-level tank 201, which functions to transport the alkaline solution, which has undergone initial cooling in the condenser, to the high-level tank 201. The second inlet of the high-level tank 201 serves as the receiving port for the condenser outlet, receiving the alkaline solution that has undergone initial cooling. After entering the high-level tank, the solution comes into contact again with the spiral cooling pipes inside the tank for secondary heat exchange. The second outlet of the high-level tank 201 is connected to the inlet of the reactor 10, responsible for feeding the alkaline solution, which has undergone two cooling processes (initial cooling by the condenser + secondary cooling by the high-level tank), into the reactor, ensuring that the solution temperature entering the reactor reaches the first predetermined temperature. Thus, the condenser first performs initial cooling of the alkaline solution, significantly reducing the initial heat of the solution, and then the high-level tank performs a second, finer cooling. This stepped cooling method avoids a single device bearing an excessive cooling load, allowing for the processing of a larger flow rate of solution in the same amount of time, thus improving the overall processing capacity of the pre-cooling system. Furthermore, by first cooling the alkaline solution to an intermediate temperature through the condenser before entering the high-level tank for fine-tuning cooling to the target temperature, the problem of unstable cooling caused by an excessively high initial solution temperature can be effectively avoided. Even if the cooling effect of the condenser fluctuates slightly, the high-level tank can compensate through secondary heat exchange, resulting in a smaller deviation in the final temperature of the solution entering the reactor.

[0030] Optionally, as an optional embodiment of the present invention, the precooling structure 20 further includes a first regulating valve 203, which is located on the connecting pipe between the second outlet of the high-level tank 201 and the first inlet of the condenser 202 to regulate the flow rate of the alkaline solution entering the condenser 202.

[0031] Specifically, the first regulating valve 203 can be a straight-through single-seat regulating valve, a fluoropolymer-lined regulating valve, or a sleeve regulating valve, etc.

[0032] Optionally, as an optional embodiment of the present invention, the precooling structure 20 further includes a second regulating valve 204, which is located on the connecting pipe between the outlet of the condenser 202 and the inlet of the reactor 10 to regulate the flow rate of the alkaline solution entering the reactor 10.

[0033] Specifically, the second regulating valve 204 can be a straight-through single-seat regulating valve, a fluoropolymer-lined regulating valve, or a sleeve regulating valve, etc.

[0034] Optionally, as an optional embodiment of this utility model, the condenser 202 is a horizontal shell-and-tube condenser.

[0035] Optionally, as an optional embodiment of this utility model, the cooling pipe 2010 is a polyethylene pipe.

[0036] Specifically, polyethylene pipes have strong chemical stability and good resistance to corrosion from alkaline solutions and cooling media (such as ordinary cooling water and neutral coolant) involved in pre-cooling structures, reducing the frequency and cost of pipe replacement and maintenance.

[0037] Optionally, as an optional embodiment of the present invention, the reactor 10 includes a jacketed cooling structure to cool the reactor to a second predetermined temperature; when the temperature of the reactor drops to the second predetermined temperature, an alkaline solution is introduced into the reactor from the second outlet to lower the temperature of the reactor to a first predetermined temperature, the first predetermined temperature being lower than the second predetermined temperature.

[0038] Specifically, the jacketed cooling structure, as a cooling component of the reactor itself, can directly and uniformly cool the reactor body by introducing a cooling medium (such as chilled water or refrigerant) into the jacket. This allows the reactor to reach a second predetermined temperature before the alkaline solution enters. Through precise, step-by-step temperature control, the jacketed cooling system completes most of the cooling load first, stabilizing the reactor temperature within a relatively controllable range (the second predetermined temperature). This avoids temperature overshoot or fluctuations caused by excessive load during a single cooling process, ensuring the final temperature accurately reaches the first predetermined temperature. It also avoids localized thermal stress caused by the high-temperature reactor body contacting the low-temperature alkaline solution, while reducing temperature rebound due to heat absorption after the alkaline solution enters, thus lowering the difficulty of temperature control. Furthermore, jacketed cooling can be performed simultaneously during the pre-cooling of the alkaline solution, reducing overall cooling time. Simultaneously, since the reactor has already reached near the first predetermined temperature, the temperature inside the reactor can be quickly adjusted to the first predetermined temperature after the alkaline solution enters, significantly improving production efficiency. In addition, if the cooled low-temperature alkaline solution is directly introduced into the high-temperature reactor, the material inside the reactor may violently churn or locally crystallize due to the large instantaneous temperature difference. However, by first cooling the reactor body to a second predetermined temperature through a jacket, the initial temperature difference between the alkaline solution and the reactor body can be reduced, making the subsequent temperature drop process more gradual and reducing safety hazards such as material splashing and pipeline blockage.

[0039] Optionally, as an optional embodiment of this utility model, the first predetermined temperature is 20℃-30℃, and the second predetermined temperature is 40℃-50℃.

[0040] The preparation apparatus provided in this embodiment of the invention features a pre-cooling structure connected to the reaction vessel. This structure allows the alkaline solution to be pre-cooled via cooling pipes. The pre-cooling process is completed through heat exchange between the cooling pipes and the alkaline solution, pre-consuming some of the heat from the alkaline solution and reducing the cooling load required to lower the temperature to the first predetermined temperature after the reaction vessel starts up, thus reducing the energy consumption of the equipment. Furthermore, since the alkaline solution is pre-cooled before entering the reaction vessel, there is no need to wait for an excessively long cooling process. The pre-cooled alkaline solution, once added to the reaction vessel, quickly brings the vessel to the first predetermined temperature and into a stable reaction stage, effectively shortening the production cycle and improving the production efficiency of neotame. By stably controlling the reaction vessel temperature to the first predetermined temperature and shortening the time required for the reaction vessel to reach that temperature, material decomposition, volatilization, or other unsafe reactions caused by excessively high temperatures or prolonged cooling times can be effectively avoided, providing a more reliable safety guarantee for industrial production.

[0041] It should be noted that the order of the above embodiments of the present invention is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0042] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

Claims

1. An apparatus for preparing neotame, characterized in that, The apparatus for preparing neotame includes a reaction vessel (10) and a precooling structure (20), wherein the precooling structure (20) is connected to the reaction vessel (10) so that an alkaline solution is precooled by the precooling structure (20) and then introduced into the reaction vessel (10). The precooling structure (20) includes a first inlet (2011), a second inlet (2012), a first outlet (2013), a second outlet (2014), and a cooling pipe (2010). The second outlet (2014) is connected to the inlet of the reactor (10). One end of the cooling pipe (2010) is connected to the first inlet (2011) to allow the cooling medium to pass through. The other end of the cooling pipe (2010) is connected to the first outlet (2013) to discharge the cooling medium. The alkaline solution enters the precooling structure (20) from the second inlet (2014) and exchanges heat with the cooling pipe (2010) before being passed into the reactor (10) from the second outlet (2014) to reduce the temperature of the reactor (10) to a first predetermined temperature.

2. The apparatus for preparing neotame according to claim 1, characterized in that, The reactor (10) includes a jacketed cooling structure to cool the reactor (10) to a second predetermined temperature; When the temperature of the reactor (10) drops to the second predetermined temperature, an alkaline solution is introduced into the reactor (10) from the second outlet to reduce the temperature of the reactor (10) to the first predetermined temperature, which is lower than the second predetermined temperature.

3. The apparatus for preparing neotame according to claim 2, characterized in that, The first predetermined temperature is 20℃-30℃, and the second predetermined temperature is 40℃-50℃.

4. The apparatus for preparing neotame according to claim 1, characterized in that, The precooling structure (20) includes a high-level tank (201), which is located above the reactor (10). The inner cavity of the high-level tank (201) is provided with a spiral cooling pipe (2010). One end of the cooling pipe (2010) is located at the top of the tank body of the high-level tank (201), and the other end of the cooling pipe (2010) is located at the bottom of the tank body of the high-level tank (201). The top of the tank body is provided with a first feed inlet (2011) and a second feed inlet (2012), and the first feed inlet (2011) is adjacent to one end of the cooling pipe (2010). The bottom of the tank body is provided with a first discharge outlet (2013) and a second discharge outlet (2014), and the first discharge outlet (2013) is adjacent to the other end of the cooling pipe (2010).

5. The apparatus for preparing neotame according to claim 4, characterized in that, The precooling structure (20) also includes a condenser (202), the first inlet of the condenser (202) is connected to the second outlet (2014), the second inlet of the condenser (202) is supplied with a cooling medium to cool the alkaline solution again, and the outlet of the condenser (202) is connected to the inlet of the reactor (10).

6. The apparatus for preparing neotame according to claim 4, characterized in that, The precooling structure (20) also includes a condenser (202). A cooling medium is introduced into the second inlet of the condenser (202), and an alkaline solution is introduced into the first inlet of the condenser (202) to cool the alkaline solution. The outlet of the condenser (202) is connected to the second inlet (2012) of the high-level tank (201) so that the cooled alkaline solution is introduced into the high-level tank (201) for further cooling, and then introduced into the reactor (10) through the second outlet (2014) of the high-level tank (201).

7. The apparatus for preparing neotame according to claim 5, characterized in that, The precooling structure (20) also includes a first regulating valve (203), which is located on the connecting pipe between the second outlet (2014) of the high-level tank (201) and the first inlet of the condenser (202) to regulate the flow rate of the alkaline solution entering the condenser (202).

8. The apparatus for preparing neotame according to claim 5, characterized in that, The precooling structure (20) also includes a second regulating valve (204), which is located on the connecting pipe between the outlet of the condenser (202) and the inlet of the reactor (10) to regulate the flow rate of the alkaline solution entering the reactor (10).

9. The neotame preparation apparatus according to claim 5 or 6, wherein the condenser (202) is a horizontal shell-and-tube condenser.

10. The apparatus for preparing neotame according to any one of claims 1-8, characterized in that, The cooling pipe (2010) is a polyethylene pipe.

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