Esterification reaction dehydration device for amino acid surfactant production

Abstract

The utility model discloses an esterification reaction dehydration device for producing an amino acid surfactant. The esterification reaction dehydration device comprises a reaction kettle, a steam pipe, a gas drying chamber, a condensation pipe and a liquid drying chamber with a siphon on the side surface, a steam outlet and a feed port are formed in the top of the reaction kettle, a discharge port is formed in the bottom of the reaction kettle, an inorganic salt dehydration device is fixedly arranged in the reaction kettle, and the steam outlet is connected with a gas inlet of the gas drying chamber through a steam pipe; a gas outlet of the gas drying chamber is connected with a valve interface of the liquid drying chamber; a condenser pipe is arranged at the top of the liquid drying chamber; the siphon inlet is connected with the bottom of the liquid drying chamber; an outlet of the siphon is connected with the reaction kettle; the inorganic salt dewatering device is a heat-resistant pipeline with one end blocked and small holes distributed in the periphery, and water-absorbing inorganic salt is placed in the pipeline after being packaged by a filter bag. The problems that in the prior art, a high-boiling-point toxic dehydrating agent is used, a water segregator is poor in water segregation effect, and the esterification rate is low are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of dehydration reaction devices, in particular to an esterification reaction dehydration device for producing amino acid surfactants. Background Art

[0002] Esterification, the direct condensation of an acid and an alcohol to form an ester and water, is a common method for preparing organic ester compounds. The acid-catalyzed esterification of carboxylic acids and alcohols is a reversible process. Generally, the reaction rate is very slow, the reaction is incomplete, and the esterification yield is insufficient. Common methods to increase the reaction rate and esterification yield include developing efficient acid catalysts, increasing the reaction temperature, using excess alcohol (or acid), and removing water from the reaction system. Removing the water generated in the esterification reaction is a widely used method, as it promotes the reversible reaction in the positive direction and effectively increases the esterification yield. In existing esterification processes, water removal is often performed using a water separator. Dehydrating agents such as benzene, toluene, and cyclohexane are added to form an azeotropic reaction with water, followed by condensation and subsequent separation in a water separator. While simple and practical, this method can be difficult to separate and poorly separate when using water-soluble low-molecule alcohols as starting materials and participating in the azeotropic reaction. Furthermore, dehydrating agents (such as benzene, toluene, and cyclohexane) are toxic and tend to remain in the esterified product. In addition, membrane separation technology is also used to remove water, but the equipment is relatively complex and the cost is high.

[0003] Amino acid surfactants are a new class of green surfactants, boasting not only excellent surface activity but also good biodegradability, mild and low irritation properties, skin affinity, biocompatibility, and antibacterial properties. Driven by the philosophy of green and safe development, they have gradually replaced traditional surfactants and are widely used in cosmetics, facial cleansers, shampoos, body washes, toothpaste, and other daily necessities. In the synthesis of amino acid ester surfactants, water-soluble small molecule alcohols, such as ethanol, n-propanol, isopropanol, n-butanol, and isobutanol, are often used as raw materials. However, effective water removal using a water separator is difficult, and more importantly, the preparation of green and safe surfactants requires avoiding the use of toxic dehydrating agents.

[0004] In view of the above-mentioned technical problems, it is necessary for technicians in this field to develop an esterification reaction dehydration device for the production of amino acid surfactants. Utility Model Content

[0005] The utility model provides an esterification reaction dehydration device for producing amino acid surfactants, which solves the problems of traditional technologies such as use of high-boiling-point toxic dehydrating agents, poor water separation effect of water separators and low esterification rate.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] An esterification reaction dehydration device for producing amino acid surfactants comprises a reactor, a steam pipe, a gas drying chamber, a condenser, and a liquid drying chamber with a siphon on the side. The reactor is provided with a steam outlet and a feed port at the top, and a discharge port at the bottom. An inorganic salt dehydration device is fixedly arranged inside the reactor. The steam outlet is connected to the air inlet of the gas drying chamber via the steam pipe. The air outlet of the gas drying chamber is connected to the valve interface of the liquid drying chamber. The top of the liquid drying chamber is provided with a condenser. The inlet of the siphon is connected to the bottom of the liquid drying chamber. The outlet of the siphon is connected to the reactor. The inorganic salt dehydration device is a heat-resistant pipe with one end blocked and surrounded by small holes. Water-absorbing inorganic salts are packaged in a filter bag and placed in the pipe, so that the water-absorbing inorganic salts are immersed in a solution for further dehydration.

[0008] Furthermore, the reactor is provided with a stirring and heating device, and the amino acid derivative, small molecule alcohol and catalyst are added from the reactor feed port to undergo esterification reaction in the reactor. The reactor is also provided with a temperature measuring device to facilitate monitoring of the temperature in the reactor.

[0009] Furthermore, the steam pipe is an evaporation channel for the alcohol / water azeotrope, and the outside of the steam pipe is wrapped with a thermal insulation layer, which can reduce energy consumption and facilitate the evaporation of the azeotrope.

[0010] Furthermore, both the gas drying chamber and the liquid drying chamber adopt molecular sieve adsorption dehydration, and recyclable molecular sieve is used as the adsorption dehydration medium, combining gas phase dehydration and liquid phase dehydration, which not only enhances the esterification dehydration effect, but also achieves energy saving and environmental protection.

[0011] Furthermore, the air inlet of the gas drying chamber is higher than the air outlet. This facilitates the entry of azeotropes passing through the steam pipe into the gas drying chamber. The molecular sieve in the gas drying chamber adsorbs and removes some of the moisture from the mixed steam. The air inlet of the gas drying chamber is higher than the air outlet, which facilitates the direct flow of small amounts of condensate into the liquid drying chamber, allowing for more complete moisture absorption.

[0012] Furthermore, the condenser uses low-temperature water or solvent as a coolant to cool the steam into condensate, and the lower end is connected to the liquid drying chamber, and the condensate flows into the liquid drying chamber.

[0013] Furthermore, the height of the siphon is the same as the molecular sieve filling height. When the liquid level reaches the height of the siphon, the dehydrated alcohol raw material flows back to the reactor in a siphon manner under the action of the siphon, realizing a continuous dehydration process and greatly improving the esterification rate.

[0014] Furthermore, a liquid level control switch device is used instead of the siphon tube. When the accumulated level of the dehydrated alcohol raw material liquid in the liquid drying chamber reaches a preset switch-on threshold of the liquid level control switch device, the switch is automatically opened, and the dehydrated alcohol raw material is returned to the reactor. The level of the dehydrated alcohol raw material liquid in the liquid drying chamber decreases to a preset switch-off threshold of the liquid level control switch device, at which point the switch is automatically closed.

[0015] Furthermore, the water-absorbing inorganic salt is at least one of sodium sulfate, magnesium sulfate, calcium sulfate and calcium chloride.

[0016] In a specific implementation, amino acid derivatives, small molecule alcohols and catalysts are put into a reactor, inorganic salts are packaged in a filter bag and placed in an inorganic salt dehydration device, and an esterification reaction occurs under the action of a heating and stirring device in the reactor to produce an esterification product and water. Part of the water is removed by contact with the inorganic salt in the inorganic salt dehydration device in the reactor, and part of the water and the small molecule alcohol form an azeotrope under heating and reflux. The azeotrope enters a gas drying chamber through a steam pipe, and the molecular sieve in the gas drying chamber adsorbs and removes part of the moisture in the mixed steam; the air inlet of the gas drying chamber is higher than the air outlet, which is beneficial A small amount of condensate flows directly into the liquid drying chamber, and then passes through the molecular sieve in the liquid drying chamber to further fully absorb moisture; most of the steam goes upward into the condenser, cools into condensate, and flows into the liquid drying chamber, where the molecular sieve in the liquid drying chamber adsorbs and removes moisture from the condensate; the height of the siphon tube on the side of the liquid drying chamber is the same as the filling height of the molecular sieve. When the liquid level in the liquid drying chamber reaches the height of the siphon tube, a siphon phenomenon occurs, and the dehydrated alcohol raw material flows back to the reactor to continue the esterification reaction, realizing a continuous dehydration process, promoting the esterification reaction to proceed in the positive direction, and greatly improving the esterification rate.

[0017] Beneficial effects

[0018] The utility model proposes an esterification reaction dehydration device for the production of amino acid surfactants. The device includes a gas drying chamber and a liquid drying chamber. A recyclable molecular sieve is used as an adsorption dehydration medium, combining gas phase dehydration and liquid phase dehydration to enhance the dehydration effect of the esterification reaction. Secondly, a siphon method is used to return the dehydrated alcohol raw material to the reactor to achieve a continuous dehydration process, greatly improving the esterification rate. Thirdly, the inorganic salt dehydration device in the reactor can absorb a portion of the water in the reactor, further improving the dehydration efficiency. The dehydration device is applied to the preparation of amino acid ester surfactants and can replace traditional water separators, avoiding the use of high-boiling-point toxic dehydrating agents, ensuring the green and non-toxic products. The device has a simple structure, is easy to operate, and is low in cost. It avoids the use of expensive membrane separation and dehydration devices, thus reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

[0020] Figure 1 This is a schematic structural diagram of an esterification reaction dehydration device for producing an amino acid surfactant provided in Example 1 of the present utility model;

[0021] Figure 2 This is a schematic structural diagram of an esterification reaction dehydration device for producing an amino acid surfactant provided in Example 2 of the present utility model;

[0022] In the figure: 1-reactor; 2-steam pipe; 3-gas drying chamber; 4-condenser; 5-liquid drying chamber; 6-siphon; 7-molecular sieve; 8-stirring and heating device; 9-inorganic salt dehydration device; 10-interlocking valve; 11-magnetic flap level gauge. DETAILED DESCRIPTION

[0023] To make the purpose, technical solution, and advantages of the present invention more clear, the technical solution of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0024] Example 1

[0025] like Figure 1 As shown, this embodiment provides an esterification reaction dehydration device for the production of amino acid surfactants, comprising a reactor 1, a steam pipe 2, a gas drying chamber 3, a condenser 4, and a liquid drying chamber 5 with a siphon 6 on the side. The reactor 1 is provided with a steam outlet and a feed port at the top and a discharge port at the bottom. The steam outlet is connected to the gas inlet of the gas drying chamber 3 via the steam pipe 2. The gas outlet of the gas drying chamber 3 is connected to the valve interface of the liquid drying chamber 5. The liquid drying chamber 5 is provided with a condenser 4 at the top. The siphon inlet is connected to the bottom of the liquid drying chamber. The siphon outlet is connected to the reactor. The inorganic salt dehydration device 9 is a heat-resistant pipe with one end blocked and surrounded by small holes. The water-absorbing inorganic salt is packaged in a filter bag and placed in the pipe from the reactor port, so that it is immersed in the solution for further dehydration. The material of the filter bag and the heat-resistant pipe can be adjusted according to actual needs and is not limited thereto. In this embodiment, the filter bag is a PTFE filter bag, and the heat-resistant pipe is a polytetrafluoroethylene pipe.

[0026] Reactor 1 is the chamber where the amino acid derivative and small molecule alcohol undergo esterification. A stirring and heating device 8 is installed within the reactor. The amino acid derivative, small molecule alcohol, and catalyst are added through the reactor's feed port, where the esterification reaction occurs under heating and stirring conditions. A temperature measuring device is also installed within the reactor to facilitate temperature monitoring.

[0027] The steam pipe 2 is an evaporation channel for the alcohol / water azeotrope. The outside of the steam pipe is wrapped with a heat-insulating layer, which can reduce energy consumption and facilitate the evaporation of the azeotrope.

[0028] Both the gas drying chamber 3 and the liquid drying chamber 5 utilize a recycle-free molecular sieve 7 as a medium for adsorption dehydration, removing some of the water from the alcohol / water azeotrope vapor. The gas drying chamber performs vapor-phase dehydration, while the liquid drying chamber performs liquid-phase dehydration. This combination of vapor-phase and liquid-phase dehydration not only enhances the esterification and dehydration process but also achieves energy conservation and environmental protection. In this embodiment, the molecular sieve is 4A.

[0029] The air inlet of the gas drying chamber 3 is higher than the air outlet. This facilitates the entry of azeotropes passing through the steam pipe into the gas drying chamber, where the molecular sieve adsorbs and removes some of the moisture from the mixed steam. Furthermore, the air inlet of the gas drying chamber is higher than the air outlet, facilitating the direct flow of small amounts of condensate into the liquid drying chamber, allowing for more complete moisture adsorption.

[0030] The condenser 4 uses low-temperature water or solvent as a coolant to cool the steam into condensate. The lower end of the condenser is connected to the liquid drying chamber 5, and the condensate flows into the liquid drying chamber.

[0031] The height of the siphon is the same as the molecular sieve filling height. When the liquid level reaches the height of the siphon, the dehydrated alcohol raw material flows back to the reactor in a siphon manner under the action of the siphon, realizing a continuous dehydration process and greatly improving the esterification rate.

[0032] The water-absorbing inorganic salt is at least one of sodium sulfate, magnesium sulfate, calcium sulfate and calcium chloride.

[0033] In a specific implementation, an amino acid derivative, a small molecule alcohol, and a catalyst are placed in a reactor 1, anhydrous sodium sulfate is packaged in a PTFE filter bag and then placed in an inorganic salt dehydration device, an esterification reaction occurs under the action of a heating and stirring device in the reactor to produce an esterification product and water, a portion of the water in the reactor is removed under the contact between the water and the sodium sulfate in the inorganic salt dehydration device 9, a portion of the water and the small molecule alcohol form an azeotrope under heating and reflux, the azeotrope enters a gas drying chamber 3 through a steam pipe 2, and a molecular sieve 7 in the gas drying chamber 4 adsorbs and removes part of the water in the mixed steam; the air inlet of the gas drying chamber 3 is larger than the air outlet The high temperature is conducive to a small amount of condensate flowing directly into the liquid drying chamber 5, and then passing through the molecular sieve 7 in the liquid drying chamber 5 to further fully absorb moisture; most of the steam flows upward into the condenser tube 4, is cooled into condensate, and flows into the liquid drying chamber 5, and the molecular sieve in the liquid drying chamber adsorbs and removes moisture in the condensate; the height of the siphon tube 6 on the side of the liquid drying chamber is the same as the filling height of the molecular sieve. When the liquid level in the liquid drying chamber reaches the height of the siphon tube 6, a siphon phenomenon occurs, and the dehydrated alcohol raw material flows back to the reactor 1 to continue the esterification reaction, realizing a continuous dehydration process, promoting the esterification reaction to proceed in the positive direction, and greatly improving the esterification rate.

[0034] Example 2

[0035] like Figure 2 As shown, the difference between this embodiment and embodiment 1 is that a liquid level control switch device is used to replace the siphon tube. In this embodiment, the liquid level control switch device uses a magnetic flap liquid level gauge 11.

[0036] In a specific implementation, an amino acid derivative, a small molecule alcohol, and a catalyst are placed in a reactor 1, anhydrous sodium sulfate is wrapped in PTFE and placed in an inorganic salt dehydration device 9, and an esterification reaction occurs under the action of a heating and stirring device in the reactor to produce an esterification product and water. A portion of the water is removed by contact with the sodium sulfate in the inorganic salt dehydration device 9 in the reactor, and a portion of the water and the small molecule alcohol form an azeotrope under heating and reflux. The azeotrope enters the gas drying chamber 3 through a steam pipe 2, and the molecular sieve 7 in the gas drying chamber 4 adsorbs and removes part of the moisture in the mixed steam; the air inlet of the gas drying chamber 3 is higher than the air outlet, which is conducive to a small amount of condensate flowing directly into the liquid drying chamber 5, and then passing through the separation of the liquid drying chamber 5. The sub-sieve 7 further fully absorbs moisture; most of the steam goes upward into the condenser 4, is cooled into condensate, and flows into the liquid drying chamber 5, where the molecular sieve in the liquid drying chamber adsorbs and removes moisture from the condensate; when the accumulated dehydrated alcohol raw material liquid level in the liquid drying chamber rises to the threshold value of the preset valve opening of the magnetic flap level gauge, the magnetic flap level gauge 11 automatically opens the interlocking valve 10, and puts the dehydrated alcohol raw material back into the reactor 1, until the accumulated dehydrated alcohol raw material liquid level in the liquid drying chamber drops to the threshold value of the preset valve closing of the magnetic flap level gauge, the interlocking valve 10 automatically closes, and the esterification reaction continues to occur, realizing a continuous dehydration process, prompting the esterification reaction to proceed in the positive direction, and greatly improving the esterification rate.

[0037] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0038] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. An esterification reaction dehydration device for producing amino acid surfactants, characterized in that: The invention comprises a reactor, a steam pipe, a gas drying chamber, a condenser and a liquid drying chamber with a siphon on the side; the reactor is provided with a steam outlet and a feed port on the top, a discharge port on the bottom, an inorganic salt dehydration device is fixedly provided inside the reactor, the steam outlet is connected to the air inlet of the gas drying chamber through a steam pipe; the air outlet of the gas drying chamber is connected to the valve interface of the liquid drying chamber; the top of the liquid drying chamber is provided with a condenser; the inlet of the siphon is connected to the bottom of the liquid drying chamber; the outlet of the siphon is connected to the reactor; the inorganic salt dehydration device is a heat-resistant pipe with one end blocked and covered with small holes on all sides, and the water-absorbing inorganic salt is packaged in a filter bag and placed in the pipe.

2. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: The reactor is provided with a stirring and heating device.

3. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: The steam pipe is an evaporation channel for the alcohol / water azeotrope, and the outside of the steam pipe is wrapped with a heat-insulating layer.

4. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: The gas drying chamber and the liquid drying chamber both use molecular sieve adsorption for dehydration.

5. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: The air inlet of the gas drying chamber is higher than the air outlet.

6. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: The condenser uses low-temperature water or solvent as the cooling liquid.

7. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: The height of the siphon tube is the same as the filling height of the molecular sieve.

8. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: A liquid level control switch device is used to replace the siphon tube.

9. The esterification reaction dehydration device for producing amino acid surfactant according to claim 1, characterized in that: The water-absorbing inorganic salt is at least one of sodium sulfate, magnesium sulfate, calcium sulfate and calcium chloride.

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