A preparation device and preparation method for continuous production of trimethylolpropane

Abstract

The invention relates to the field of organic compound synthesis, and specifically discloses a preparation device and a preparation method for continuously producing trimethylolpropane, which breaks through the limitation of current intermittent reactor production, ensures that various materials are fully and evenly mixed in the reactor body through the structure of the reactor body, improves the efficiency and conversion rate of the chemical reaction, avoids the problems of aggravated side reactions or catalyst deactivation caused by excessive local concentration, and helps to reduce the waste of catalysts and reduce production costs; a mixed solution of n-butyraldehyde and a catalyst is added to a plurality of feed pipes above each layer of a perforated dispersion plate in a layer-by-layer decreasing manner, monitors in real time and adjusts the reaction temperature in the reactor body by adjusting the feed amount of the mixed solution of n-butyraldehyde and the catalyst, ensures that the entire production process is always carried out within an optimal temperature range, ensures that the product quality reaches a preset standard, effectively reduces energy consumption and equipment loss, and improves production efficiency and economic benefits.

Description

Technical Field

[0001] The invention relates to the field of organic compound synthesis, in particular to a preparation device and a preparation method for continuously producing trimethylolpropane. Background Art

[0002] Trimethylolpropane is a commonly used chain extender in the resin industry. It has three hydroxymethyl groups in its molecular structure and has properties similar to those of polyols. It can react chemically with a variety of compounds. In the resin manufacturing process, trimethylolpropane can be used as a reactant to participate in the synthesis of resins and improve the properties of resins, such as improving the heat resistance, water resistance, and chemical corrosion resistance of resins. Therefore, it is often used in the production of alkyd resins, polyurethane resins, unsaturated resins, polyester resins, etc.

[0003] At present, there are two main methods for producing trimethylolpropane: the cross-Canizaro condensation method (also known as the sodium formate method) and the aldehyde hydrogenation reduction method. The raw materials of the cross-Canizaro condensation method are n-butyraldehyde and formaldehyde. n-Butyraldehyde and formaldehyde aqueous solution undergo an aldol condensation reaction under the action of an alkaline catalyst to generate 2,2-dimethylolbutyraldehyde, which then undergoes a cross-Canizaro reaction with excess formaldehyde under strong alkaline conditions to generate trimethylolpropane. At the same time, formaldehyde is oxidized to generate formic acid, which is neutralized with sodium hydroxide to generate sodium formate. The reaction mixture is then desalted and refined to obtain a qualified trimethylolpropane product. The raw materials of the aldehyde hydrogenation reduction method are n-butyraldehyde and formaldehyde. n-Butyraldehyde and formaldehyde generate an aldol condensation product 2,2-dimethylolbutyraldehyde under the catalytic action of a trialkylamine, which is then subjected to aqueous hydrogenation in the presence of a catalyst to obtain trimethylolpropane.

[0004] The above two methods are relatively mature production processes, but both methods are batch reactions in kettles, which result in unbalanced reaction temperature, poor material mixing effect, high formaldehyde consumption, more by-products, poor product quality, large post-processing workload, high production cost, etc. In view of the above situation, the present invention proposes a preparation device and a preparation method for continuously producing trimethylolpropane. Summary of the invention

[0005] The purpose of the present invention is to provide a preparation device and a preparation method for continuously producing trimethylolpropane, which can solve the problems of unbalanced reaction temperature, poor material mixing effect, high formaldehyde consumption, more by-products, poor product quality, large post-processing workload, high production cost, etc. in the intermittent process of trimethylolpropane production by disproportionation method.

[0006] In order to solve the above technical problems, the present invention provides a preparation device for continuously producing trimethylolpropane, including a reactor body, the reactor body including an upper part and a lower part arranged from top to bottom, the top of the upper part is provided with a feed port, and a plurality of layers of perforated dispersion plates are provided in the upper part, two adjacent layers of the perforated dispersion plates are cross-arranged and a thermometer is provided between them, a plurality of feed pipes are provided above each layer of the perforated dispersion plates, and the plurality of feed pipes are circumferentially arranged on the side wall of the upper part, a plurality of layers of packing areas are provided in the lower part and a cavity is provided between two adjacent layers of the packing areas, a thermometer is provided on one side of the cavity, and a collection port is provided at the bottom of the lower part.

[0007] Furthermore, each layer of the perforated dispersion plate includes a connecting plate and a bottom plate, a second cavity is provided between the connecting plate and the bottom plate, a discharge port is provided on one side of the second cavity, and a plurality of capillary discharge holes are opened on the connecting plate.

[0008] Furthermore, the connecting plate is provided with reinforcing ribs, and a plurality of the capillary discharge holes are symmetrically arranged on both sides of the reinforcing ribs, and the plurality of the capillary discharge holes are distributed in an annular direction and at equal distances from each other, and each of the capillary discharge holes includes two conical holes that are symmetrically arranged and connected to each other.

[0009] Furthermore, the inner wall of the feed end of each feed pipe is provided with symmetrically arranged stoppers and a feed hole is provided between them.

[0010] Furthermore, the height between two adjacent layers of the perforated dispersion plates is set to H, and the position of each feed pipe is set at 2 / 3H above the perforated dispersion plate of the lower layer.

[0011] Furthermore, the perforated dispersion plate is provided with 5-10 layers, the filler area is provided with 5-10 layers, and the filler in the filler area is a ceramic plate filler.

[0012] On the other hand, the present invention also provides a method for continuously producing trimethylolpropane, which is prepared by using the above-mentioned preparation device for continuously producing trimethylolpropane. The preparation method comprises:

[0013] A low-temperature formaldehyde aqueous solution is added from the feed port on the upper part of the reactor body, and a mixed solution of n-butyraldehyde and a catalyst is added to a plurality of feed pipes above each layer of the perforated dispersion plate in a layer-by-layer decreasing manner, and the reaction temperature in the reactor body is adjusted by real-time monitoring with a thermometer and by adjusting the feed amount of the mixed solution of n-butyraldehyde and the catalyst;

[0014] Among them, the low-temperature formaldehyde aqueous solution and the mixed solution of n-butyraldehyde and the catalyst in each layer are evenly distributed in each layer of the perforated dispersion plate and participate in the reaction. Then the mixed solution enters the perforated dispersion plate of the next layer downward through the discharge port of the perforated dispersion plate and continues to be evenly distributed and react, until it enters the packing area at the lower part of the reactor body through the discharge port from the bottom layer of the perforated dispersion plate. The solution is repeatedly exchanged internally with the cavity in each layer to form alternating horizontal flow and turbulent flow. After the reaction is finally completed, the product solution is extracted through the extraction port at the lower part of the reactor body.

[0015] Furthermore, the catalyst is liquid alkali.

[0016] Furthermore, the formaldehyde aqueous solution is prepared from formaldehyde and water, the molar ratio of formaldehyde, water, n-butyraldehyde and liquid alkali in the reactor body is 3.0-3.1:5-20:1:1-1.1, the entire reaction time is 45-65 minutes, and the reaction temperature is 20-30°C.

[0017] Furthermore, the concentration of the formaldehyde is 5%-25% and the temperature is 10-15°C; the temperature of the butyraldehyde is 10-15°C.

[0018] The beneficial effects of the present invention are:

[0019] 1. The preparation device for continuously producing trimethylolpropane of the present invention can be used for continuously producing trimethylolpropane, breaking through the limitation of the current batch reactor production, improving the production efficiency of trimethylolpropane, ensuring the product quality and maintaining the stability and safety of the production process; specifically, through the design of the reactor body structure of the present invention, it can ensure that the materials are fully mixed in the reactor body and reach a uniform state, and this uniform mixing not only greatly improves the efficiency and conversion rate of the chemical reaction, avoids the problems of aggravated side reactions or catalyst deactivation caused by excessive local concentration, but also helps to reduce the waste of catalysts and reduce production costs;

[0020] Specifically, through the design of several layers of perforated dispersion plates and several capillary discharge holes, it can ensure that the reactant liquid can quickly and evenly diffuse to the entire reaction space after entering the reactor body, which can effectively prevent the reaction unevenness caused by excessively high or low local concentration, thereby ensuring that the catalytic reaction proceeds smoothly under a nearly ideal state; this design not only significantly improves the reaction speed and efficiency, but also effectively reduces the probability of side reactions, reducing formaldehyde side reactions by more than 20%, which is conducive to the production of products with more stable quality and more standard performance;

[0021] Furthermore, by providing a plurality of feed pipes above each layer of the perforated dispersion plate, and by circumferentially arranging the plurality of feed pipes on the upper side wall, the feed pipes are scientifically arranged along the height direction of the reactor body, allowing the catalyst and the n-butyraldehyde mixed solution to be added layer by layer at different heights, thereby optimizing the residence time distribution of the reactants in the reactor body, making the reaction process more sufficient and uniform; and the design of the multi-layer feed pipes here also has the function of regulating the reaction rate, effectively preventing overheating or violent chemical reactions caused by excessively high local catalyst concentrations, and reducing the amount of catalyst used by 10% to 15%, thereby ensuring the smooth progress of the production process and reducing safety risks;

[0022] In addition, the present invention provides a thermometer 1 between two adjacent layers of perforated dispersion plates, a cavity 1 between two adjacent layers of filler areas, and a thermometer 2 on one side of the cavity 1, so that the reaction temperature inside the reactor body can be accurately adjusted by adjusting the feed amount in each layer of the feed pipe, and the reaction temperature in the system can be effectively controlled to prevent high-temperature polymerization and disproportionation reaction of formaldehyde caused by excessively rapid temperature rise, thereby ensuring that the entire production process is always carried out within the optimal temperature range, which can not only ensure that the product quality meets the preset standard, but also effectively reduce energy consumption and equipment loss, and improve production efficiency and economic benefits;

[0023] The design of the reactor body of the present invention that a plurality of layers of packing areas are provided at the bottom and a cavity is provided between two adjacent layers of packing areas can avoid the side reaction caused by the heat generated by the accumulation of materials to the greatest extent, and significantly optimize the flow field structure inside the reactor body. Specifically, the solution can be repeatedly exchanged internally through the packing and the cavity to form an effect of alternating advection and turbulence, thereby preventing the local accumulation of materials from causing side reactions, helping to maintain a relatively stable flow velocity of reactants and products in the reactor body, reducing turbulence and instability caused by flow velocity differences, thereby improving the reaction efficiency and ensuring the high stability of the reaction process;

[0024] 2. The method for preparing trimethylolpropane by continuous production of the present invention can realize the continuous production of high-quality trimethylolpropane, and in the whole process, the mixed solution of n-butyraldehyde and the catalyst is continuously and stably added to the reactor body through a precise metering system to ensure that they are fully mixed and uniform in the internal space of the reactor body, which not only greatly improves the efficiency and conversion rate of the chemical reaction, avoids the problems of aggravated side reactions or catalyst deactivation caused by excessive local concentration, but also helps to reduce the waste of catalysts and reduce production costs;

[0025] Specifically, the present invention adopts a temperature monitoring system in which thermometer 1 and thermometer 2 are integrated, and a mixed solution of n-butyraldehyde and a catalyst is added to a plurality of feed pipes above each layer of a perforated dispersion plate in a layer-by-layer decreasing manner. The reaction temperature in the reactor body is adjusted by real-time monitoring through the temperature monitoring system and by adjusting the feed amount of the mixed solution of n-butyraldehyde and the catalyst, thereby ensuring that the entire production process is always carried out within an optimal temperature range. This can not only ensure that the product quality meets the preset standard, but also effectively reduce energy consumption and equipment loss, and improve production efficiency and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a schematic structural diagram of a preparation device for continuously producing trimethylolpropane according to the present invention;

[0028] Figure 2 It is a schematic structural diagram of a perforated dispersion plate of a preparation device for continuously producing trimethylolpropane according to the present invention;

[0029] Figure 3 yes Figure 2 A magnified image of area A;

[0030] Figure 4 It is a top view of a perforated dispersion plate of a preparation device for continuously producing trimethylolpropane according to the present invention;

[0031] Figure 5 It is a structural schematic diagram of a feed pipe of a preparation device for continuously producing trimethylolpropane according to the present invention;

[0032] In the figure: 1-reactor body, 11-upper part, 12-lower part, 111-feeding port, 112-perforated dispersion plate, 113-thermometer 1, 114-feeding pipe, 121-filling area, 122-cavity 1, 123-thermometer 2, 124-collecting port, 1121-connecting plate, 1122-bottom plate, 1123-cavity 2, 1124-feeding port, 1125-capillary discharge hole, 1126-reinforcement rib, 11251-conical hole, 1141-block, 1142-feeding port. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In a specific embodiment of the present invention, Figure 1-5 As shown, a preparation device for continuously producing trimethylolpropane includes a reactor body 1, and the reactor body 1 includes an upper part 11 and a lower part 12 arranged from top to bottom. A feed port 111 is provided at the top of the upper part 11, and a plurality of layers of perforated dispersion plates 112 are provided in the upper part 11, two adjacent layers of perforated dispersion plates 112 are cross-arranged and a thermometer 113 is provided between them, a plurality of feed pipes 114 are provided above each layer of perforated dispersion plates 112, and the plurality of feed pipes 114 are circumferentially arranged on the side wall of the upper part 11, a plurality of layers of filling areas 121 are provided in the lower part 12, and a cavity 122 is provided between two adjacent layers of filling areas 121, a thermometer 2 123 is provided on one side of the cavity 122, and a collection port 124 is provided at the bottom of the lower part 12.

[0035] The preparation device for continuously producing trimethylolpropane of the present invention can be used for continuously producing trimethylolpropane, breaking through the limitation of current batch reactor production, improving the production efficiency of trimethylolpropane, ensuring product quality and maintaining the stability and safety of the production process; specifically, through the design of the reactor body structure of the present invention, it can be ensured that various materials are fully mixed in the reactor body and reach a uniform state, and such uniform mixing not only greatly improves the efficiency and conversion rate of the chemical reaction, avoids the problems of aggravated side reactions or catalyst deactivation caused by excessive local concentration, but also helps to reduce the waste of catalysts and reduce production costs;

[0036] like Figure 2-4In this embodiment, each layer of the perforated dispersion plate 112 includes a connecting plate 1121 and a bottom plate 1122, a cavity 1123 is provided between the connecting plate 1121 and the bottom plate 1122, a discharge port 1124 is provided on one side of the cavity 1123, and a plurality of capillary discharge holes 1125 are opened on the connecting plate 1121; a reinforcing rib 1126 is provided on the connecting plate 1121, and the plurality of capillary discharge holes 1125 are symmetrically arranged on both sides of the reinforcing rib 1126, and the plurality of capillary discharge holes 1125 are circumferentially spaced and equidistant from each other. The capillary discharge hole 1125 includes two tapered holes 11251 which are symmetrically arranged and connected to each other. This design enables the low-temperature formaldehyde aqueous solution, the catalyst and the mixed solution of n-butyraldehyde to continuously and evenly enter the cavity two for reaction, and can ensure that the materials are fully mixed in the cavity two and the reactor body and reach a uniform state, which greatly improves the efficiency and conversion rate of the chemical reaction, avoids the problems of aggravated side reactions or catalyst deactivation caused by excessive local concentration, and helps to reduce the waste of catalysts and reduce production costs.

[0037] like Figure 5 In this embodiment, the inner wall of the feed end of each feed pipe 114 is provided with symmetrically arranged blocks 1141 and a feed hole 1142 is provided between them; this design enables the mixed solution of the catalyst and n-butyraldehyde to stir the solution to form a local vortex during the process of quickly entering the reaction solution, thereby achieving the effect of rapid mixing and catalysis, and improving the efficiency and conversion rate of the chemical reaction.

[0038] Specifically, the height between two adjacent layers of perforated dispersion plates 112 is set to H, and the position of each feed pipe 114 is set at 2 / 3H above the lower layer of perforated dispersion plate 112; this height is conducive to the mixed solution of catalyst and n-butyraldehyde to diffuse into the reaction liquid evenly at the fastest speed, thereby improving the efficiency and conversion rate of the chemical reaction.

[0039] In this embodiment, the perforated dispersion plate 112 is set to 5-10 layers, and the filling area 121 is set to 5-10 layers. The filler of the filling area 121 is a ceramic plate filler, which can avoid the side reactions caused by material aggregation and heat generation to the greatest extent, and can significantly optimize the flow field structure inside the reactor body, which helps to maintain a relatively stable flow velocity of the reactants and products in the reactor, and reduce turbulence and instability caused by flow velocity differences, thereby improving the reaction efficiency and ensuring the high stability of the reaction process.

[0040] On the other hand, the present invention also provides a method for continuously producing trimethylolpropane, which is prepared by using the above-mentioned preparation device for continuously producing trimethylolpropane. The preparation method comprises:

[0041] A low-temperature formaldehyde aqueous solution is added from the feed port 111 of the upper portion 11 of the reactor body 1, and at the same time, a mixed solution of n-butyraldehyde and a catalyst is added to a plurality of feed pipes 114 above each layer of a perforated dispersion plate 112 in a layer-by-layer decreasing manner, wherein the mixed solution of n-butyraldehyde and the catalyst is continuously and stably added to the reactor body through a precise metering system to ensure that it is fully mixed in the internal space of the reactor body and reaches a uniform state, and the reaction temperature in the reactor body 1 is adjusted by real-time monitoring through a thermometer 113 and by adjusting the feed amount of the mixed solution of n-butyraldehyde and the catalyst;

[0042] Among them, the low-temperature formaldehyde aqueous solution and the mixed solution of n-butyraldehyde and liquid alkali in each layer are evenly distributed in the perforated dispersion plate 112 of each layer and participate in the reaction, and then the mixed solution enters the perforated dispersion plate 112 of the next layer downward through the discharge port 1124 of the perforated dispersion plate 112 to continue to be evenly distributed and react, until it enters the packing area 121 of the lower part 12 of the reactor body 1 through the discharge port 1124 from the bottom perforated dispersion plate 112, and the solution is repeatedly exchanged internally with the cavity 122 of each layer to form an alternating effect of horizontal flow and turbulence, thereby preventing local accumulation of materials from causing side reactions, and finally after the reaction is completed, the product solution is extracted through the extraction port 124 of the lower part 12 of the reactor body 1;

[0043] Specifically, the formaldehyde aqueous solution is prepared from formaldehyde and water, the amount ratio of formaldehyde, water, n-butyraldehyde and liquid alkali in the reactor body 1 is 3.0-3.1:5-20:1:1-1.1, the whole reaction time is 45-65min, the reaction temperature is 20-30°C; the concentration of formaldehyde is 5%-25%, the temperature is 10-15°C; the temperature of butyraldehyde is 10-15°C.

[0044] The method for preparing trimethylolpropane in a continuous manner can realize the continuous production of high-quality trimethylolpropane, and in the entire process, a mixed solution of n-butyraldehyde and a catalyst is continuously and stably added to a reactor body through a precise metering system to ensure that the mixed solution is fully mixed in the internal space of the reactor body and reaches a uniform state, which not only greatly improves the efficiency and conversion rate of the chemical reaction, avoids the problems of aggravated side reactions or catalyst deactivation caused by excessive local concentration, but also helps to reduce the waste of catalysts and reduce production costs;

[0045] The present invention adopts a temperature monitoring system in which a thermometer 1 and a thermometer 2 are integrated, and a mixed solution of n-butyraldehyde and a catalyst is added to a plurality of feed pipes above each layer of a perforated dispersion plate in a layer-by-layer decreasing manner. The temperature monitoring system monitors in real time and adjusts the feed amount of the mixed solution of n-butyraldehyde and the catalyst to adjust the reaction temperature in the reactor body, thereby ensuring that the entire production process is always maintained within an optimal temperature range. This not only ensures that the product quality reaches a preset standard, but also effectively reduces energy consumption and equipment loss, and improves production efficiency and economic benefits.

[0046] The above disclosure is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A preparation device for continuously producing trimethylolpropane, characterized in that: The invention comprises a reactor body (1), wherein the reactor body (1) comprises an upper part (11) and a lower part (12) arranged from top to bottom, wherein a feed port (111) is arranged at the top of the upper part (11), and a plurality of layers of perforated dispersion plates (112) are arranged in the upper part (11), two adjacent layers of the perforated dispersion plates (112) are arranged crosswise and a thermometer (113) is arranged between them, a plurality of feed pipes (114) are arranged above each layer of the perforated dispersion plates (112), and the plurality of feed pipes (114) are arranged circumferentially on the side wall of the upper part (11), wherein a plurality of layers of filling areas (121) are arranged in the lower part (12), and a cavity (122) is arranged between two adjacent layers of the filling areas (121), a thermometer (123) is arranged on one side of the cavity (122), and a collection port (124) is arranged at the bottom of the lower part (12).

2. The continuous production device for trimethylolpropane according to claim 1, characterized in that: The perforated dispersion plate (112) of each layer comprises a connecting plate (1121) and a bottom plate (1122), a second cavity (1123) is provided between the connecting plate (1121) and the bottom plate (1122), a discharge port (1124) is provided on one side of the second cavity (1123), and a plurality of capillary discharge holes (1125) are provided on the connecting plate (1121).

3. A preparation device for continuously producing trimethylolpropane according to claim 2, characterized in that: The connecting plate (1121) is provided with a reinforcing rib (1126), and a plurality of the capillary discharge holes (1125) are symmetrically arranged on both sides of the reinforcing rib (1126), the plurality of the capillary discharge holes (1125) are distributed in a circular direction and at equal distances from each other, and each of the capillary discharge holes (1125) includes two tapered holes (11251) that are symmetrically arranged and connected to each other.

4. The continuous production device for trimethylolpropane according to claim 1, characterized in that: The inner wall of the feeding end of each feeding pipe (114) is provided with stoppers (1141) which are symmetrically arranged with each other and a feeding hole (1142) is provided between them.

5. The continuous production device for trimethylolpropane according to claim 1, characterized in that: The height between two adjacent layers of the perforated dispersion plates (112) is set to H, and the position of each feed pipe (114) is set at 2 / 3H above the perforated dispersion plate (112) of the lower layer.

6. The continuous production device for trimethylolpropane according to claim 1, characterized in that: The number of the perforated dispersion plates (112) is 5-10, the number of the filler area (121) is 5-10, and the filler in the filler area (121) is a ceramic plate filler.

7. A method for continuously producing trimethylolpropane, using any one of the above-mentioned 1-6 continuous production equipment for producing trimethylolpropane, characterized in that: The preparation method comprises: A low-temperature formaldehyde aqueous solution is added from a feed port (111) at the upper portion (11) of the reactor body (1), and a mixed solution of n-butyraldehyde and a catalyst is added to a plurality of feed pipes (114) above each layer of a perforated dispersion plate (112) in a layer-by-layer decreasing manner, and the reaction temperature in the reactor body (1) is adjusted by real-time monitoring with a thermometer (113) and by adjusting the feed amount of the mixed solution of n-butyraldehyde and the catalyst; The low-temperature formaldehyde aqueous solution and the mixed solution of n-butyraldehyde and the catalyst in each layer are uniformly distributed in each layer of the perforated dispersion plate (112) and participate in the reaction. Then, the mixed solution flows downward through the discharge port (1124) of the perforated dispersion plate (112) to enter the perforated dispersion plate (112) of the next layer and continues to be uniformly distributed and react until it enters the packing area (121) of the lower part (12) of the reactor body (1) from the bottom perforated dispersion plate (112) through the discharge port (1124). The solution is repeatedly exchanged internally through the packing area (121) of each layer and the cavity 1 (122), forming alternating horizontal flow and turbulent flow. Finally, after the reaction is completed, the product solution is collected through the collection port (124) of the lower part (12) of the reactor body (1).

8. The method for continuously producing trimethylolpropane according to claim 7, characterized in that: The catalyst is liquid alkali.

9. The method for continuously producing trimethylolpropane according to claim 8, characterized in that: The formaldehyde aqueous solution is prepared from formaldehyde and water. The molar ratio of formaldehyde, water, n-butyraldehyde and liquid alkali in the reactor body (1) is 3.0-3.1:5-20:1:1-1.

1. The entire reaction time is 45-65 minutes and the reaction temperature is 20-30°C.

10. The method for continuously producing trimethylolpropane according to claim 9, characterized in that: The concentration of the formaldehyde is 5%-25% and the temperature is 10-15°C; the temperature of the butyraldehyde is 10-15°C.

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