Diethyl phosphite reaction device and process

Abstract

The device comprises a kettle body and a kettle cover covering the kettle body, a stirring device extending into the kettle body is arranged on the kettle cover, an annular spacer bush arranged in the circumferential direction of the kettle body is arranged on the side wall of the kettle body, and an annular heat exchange cavity is defined by the spacer bush and the kettle body; an annular vertical plate lower than the heat exchange cavity is arranged in the middle of the heat exchange cavity and divides the lower side of the heat exchange cavity into an inner cavity and an outer cavity, a water inlet pipe and an exhaust pipe are arranged on the side wall of the outer cavity, a heating coil is arranged on the lower side of the outer cavity, and the water inlet pipe is located on the lower side of the spacer bush. The exhaust pipe is located on the upper side of the spacer bush and extends to the bottom of the inner cavity of the heat exchange cavity through a pipeline, and control valves are arranged on the water inlet pipe and the exhaust pipe. According to the reaction kettle, the spacer bush is arranged on the reaction kettle, the space in the spacer bush is divided into the two cavities, the kettle body is heated through water vapor generated by the outer cavity in the initial stage of reaction, and water at the proper reaction temperature is circularly introduced through the external heating water tank in the middle stage of reaction so as to ensure that the reaction is in the most proper temperature range; and the whole process is realized through one set of structure, so that the reaction kettle has the advantages of simple structure, more reasonable temperature regulation, facilitation of accelerating the reaction efficiency and time saving.

Description

Technical Field

[0001] The present invention relates to a reaction kettle, in particular to a diethyl phosphite reaction device and process. Background Art

[0002] Phosphorous acid and ethanol can undergo an esterification reaction to produce diethyl phosphite and water. In industrial production, the reaction of phosphorous acid and ethanol is usually carried out in an esterification reactor, which is a chemical equipment specially used for esterification reactions.

[0003] Patent application number CN202410197346.9 discloses a raw material esterification reactor for the production of copper extraction agents, which includes: a reactor body; a heat exchange mechanism, including a heat exchange jacket and a heat exchange sleeve, the heat exchange sleeve is composed of a sleeve outer shell and a sleeve inner liner interlayer; and a stirring mechanism.

[0004] The above patent controls the reaction temperature in the kettle by setting up a heat exchange jacket, but the process generally includes two steps, early heating and late insulation. The insulation effect is better through heat exchange medium, but the early heating process is relatively slow, which will affect production efficiency. Summary of the Invention

[0005] Based on the problem that the reactor in the prior art uses a jacket and a heat exchange medium for heat exchange, and the efficiency of the early heating process is low, the present invention provides a diethyl phosphite reaction device and process.

[0006] The technical solution adopted by the present invention to solve the above technical problems is: A diethyl phosphite reaction device comprises a kettle body and a kettle cover covering the kettle body, the kettle cover is provided with a stirring device extending into the kettle body, the side wall of the kettle body is provided with an annular spacer arranged along the circumference of the kettle body, and an annular heat exchange chamber is formed between the spacer and the kettle body, the middle part of the heat exchange chamber is provided with an annular vertical plate with a height lower than the height of the heat exchange chamber, the annular vertical plate divides the lower part of the heat exchange chamber into an inner chamber and an outer chamber, the side wall of the outer chamber is provided with a water inlet pipe and an exhaust pipe, and the lower side of the outer chamber is provided with a heating coil, the water inlet pipe is located on the lower side of the spacer, the exhaust pipe is located on the upper side of the spacer and extends to the bottom of the inner chamber of the heat exchange chamber through a pipeline, and control valves are provided at both the water inlet pipe and the exhaust pipe.

[0007] Preferably, the valve at the exhaust pipe includes a pressure relief valve and an electrically controlled valve which are arranged in sequence, wherein the pressure relief valve is a pressure-adjustable pressure relief valve.

[0008] Preferably, the water inlet pipe is connected to a tee and equipped with an electric three-way mixing valve, one end of the tee is connected to a water adding pipe for adding normal temperature water to the outer chamber, and the other end of the tee is connected to a circulating water pipe for adding temperature-controlled hot water to the outer chamber.

[0009] Preferably, an external heating water tank is included, a circulating water pipe and a drain pipe are connected to the circulating water tank, and a pump is provided at the circulating water pipe.

[0010] Preferably, a serpentine heat exchange tube is provided in the heating water tank, one end of the heat exchange tube is connected to the outside world, and the other end is connected to the exhaust pipe.

[0011] Preferably, the stirring device includes a stirring motor, a stirring shaft arranged at the output end of the stirring motor and a stirring blade arranged on the stirring shaft, and the stirring shaft rotation seal passes through the kettle cover and extends into the kettle body.

[0012] Preferably, the kettle further comprises a controller and a plurality of thermocouples arranged in the kettle body, and each control valve, stirring motor and thermocouple are electrically connected to the controller.

[0013] The manufacturing process of diethyl phosphite comprises the following steps: S1, adding the raw materials and additives to the diethyl phosphite reaction device and mixing; S2, stirring, stirring the mixture by a stirring device; S3, temperature control, while stirring, the temperature is controlled by the above-mentioned diethyl phosphite reaction device, and the temperature control includes a heating stage, a heat preservation stage and a cooling stage. During the heating stage, the water inlet pipe is opened to add a certain amount of water to the outer chamber of the heat exchange chamber so that the heating coil is immersed, and then the water in the outer chamber of the heat exchange chamber is heated to boiling by the heating coil to generate water vapor, and the generated water vapor first rises and then falls through the partition and is discharged through the exhaust pipe; during the heat preservation stage, the valves at the water inlet pipe and the exhaust pipe are opened to continuously introduce constant temperature water into the heat exchange chamber, and the temperature of the introduced water is slightly higher than the reaction temperature until the end of the reaction; at the end of the reaction, as the product concentration increases, water at room temperature is introduced through the water inlet pipe and the drain pipe to cool the kettle; S4, separation, separation of by-products from the reaction mixture; S5, filtering or separating to remove the generated solid residue; S6, purification by distillation, further purifying diethyl phosphite by distillation.

[0014] In step S3, two branches are set at the outer end of the water inlet pipe and the water circuit switching is controlled by an electric three-way mixing valve. One branch is connected to the tap water pipe, and the other branch is connected to the heating water tank and forms a circulating water circuit with the drain pipe. The exhaust pipe discharges the steam or exchanges heat with the heating water tank through the pipeline. During the reaction process, the reaction temperature is controlled by setting a temperature sensor in the kettle body, and then the water source is switched through the two branches of the water inlet pipe to achieve temperature increase or decrease.

[0015] In step S3, during the temperature rising stage, a pressure relief valve is provided at the exhaust pipe, and the pressure in the heat exchange chamber is adjusted by adjusting the pressure of the pressure relief valve, thereby increasing the temperature of the steam and accelerating the temperature rising process.

[0016] Compared with the prior art, the advantages of the present invention are as follows: the present application sets a spacer on the reactor and divides the space inside the spacer into two chambers. In the early stage of the reaction, water vapor is generated by the outer chamber to heat the reactor body. In the middle stage, water suitable for the reaction temperature is circulated through an external heating water tank to ensure that the reaction is within the most suitable temperature range. In the later stage, normal temperature tap water is used for cooling. The entire process is realized through a set of structures, which has a simple structure and more reasonable temperature adjustment, which is conducive to accelerating the efficiency of the reaction and saving time. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be described in further detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and should not be construed as limiting the scope of the present invention. Furthermore, unless otherwise specified, the drawings are merely schematic representations of the composition or structure of the depicted objects and may contain exaggerated representations. Furthermore, the drawings are not necessarily drawn to scale.

[0018] Figure 1 A perspective view of this application; Figure 2 A cross-sectional view of the present application; Figure 3 This is a cross-sectional view of the heating water tank; In the figure: 101, kettle body; 102, kettle cover; 20, stirring device; 300, exhaust pipe; 301, water inlet pipe; 302, circulating water pipe; 303, three-way mixing valve; 304, pump; 305, heating water tank; 3051, heat exchange tube; 306, overflow valve; 307, pressure relief valve; 308, electric control valve; 309, drain valve; 310, spacer; 311, annular partition; 312, heating coil; 313, inner chamber; 314, outer chamber; 40, thermocouple. DETAILED DESCRIPTION

[0019] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are only illustrative and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0020] It should be noted that like reference numerals denote like items in the following drawings, and thus, once an item is defined in one drawing, it may not be further defined or explained in subsequent drawings.

[0021] Example 1: This embodiment mainly describes the title of the diethyl phosphite reaction device, which is as follows: Diethyl phosphite reaction device, such as Figure 1-3 As shown, it includes a kettle body 101 and a kettle cover 102 covering the kettle body 101, the kettle cover 102 is provided with a stirring device 20 extending into the kettle body 101, the side wall of the kettle body 101 is provided with an annular spacer 310 arranged along the circumference of the kettle body 101, and an annular heat exchange chamber is formed between the spacer 310 and the kettle body 101, the middle of the heat exchange chamber is provided with an annular vertical plate with a height lower than the height of the heat exchange chamber, the annular vertical plate divides the lower part of the heat exchange chamber into an inner chamber 313 and an outer chamber 314, the side wall of the outer chamber 314 is provided with a water inlet pipe 301 and an exhaust pipe 300, and the lower side of the outer chamber 314 is provided with a heating coil 312, the water inlet pipe 301 is located at the lower side of the spacer 310, the exhaust pipe 300 is located on the upper side of the spacer 310 and extends to the bottom of the inner chamber 313 of the heat exchange chamber through a pipeline, and control valves are provided at both the water inlet pipe 301 and the exhaust pipe 300.

[0022] Preferably, the valve at the exhaust pipe 300 includes a pressure relief valve 307 and an electrically controlled valve 308, which are arranged in sequence. The pressure relief valve 307 is a pressure-adjustable pressure relief valve 307. When water vapor is discharged, the electrically controlled valve 308 is first opened, and the opening pressure of the pressure relief valve 307 is adjusted to adjust the pressure of the steam discharge, thereby adjusting the temperature of the steam to a certain extent and shortening the initial heating process. The inlet and outlet of the pressure relief valve 307 are both connected to the exhaust pipe 300. It has a valve core compressed by a spring. When the internal air pressure increases, the valve core is pushed up, opening the internal channel, and the exhaust pipes 300 on both sides are connected. When the pressure needs to be adjusted, the knob is turned downward to press the spring downward, thereby increasing the pressure required to push the valve core up.

[0023] Preferably, the water inlet pipe 301 is connected to a tee and equipped with an electric three-way mixing valve 303. One end of the tee is connected to a water supply pipe for adding normal temperature water to the outer chamber 314, and the other end of the tee is connected to a circulating water pipe 302 for adding temperature-controlled hot water to the outer chamber 314. An external heating water tank 305 is also included. The circulating water pipe 302 and a drain pipe are connected to the circulating water tank, and a pump 304 is installed on the circulating water pipe 302. The water supply pipe is used to add tap water, while the circulating water pipe 302 is used to pump the water pump 304 in the heating water tank 305 into the spacer 310.

[0024] Preferably, a serpentine heat exchange tube 3051 is provided within the heating water tank 305. One end of the heat exchange tube 3051 extends above the water surface of the heating water tank 305, and a relief valve 306 is provided between the water surface and the top opening of the heat exchange tube 3051. The exhaust pipe 300 has two branches: one connected to the heat exchange tube 3051 and provided with an electrically controlled valve 308, and the other connected to the outside world and provided with an electrically controlled drain valve 309. The serpentine heat exchange tube 3051 is used to exchange heat with the heating water tank 305 by transferring steam generated at the end of the reaction.

[0025] Preferably, the stirring device 20 includes a stirring motor, a stirring shaft arranged at the output end of the stirring motor, and a stirring blade arranged on the stirring shaft. The stirring shaft rotates and seals through the kettle cover 102 and extends into the kettle body 101.

[0026] Preferably, the kettle further comprises a controller and a plurality of thermocouples 40 disposed in the kettle body 101 , and each control valve, stirring motor and thermocouple 40 are electrically connected to the controller.

[0027] Example 2: This embodiment mainly describes the title of the process of diethyl phosphite reaction, which is as follows: The manufacturing process of diethyl phosphite comprises the following steps: S1, adding the raw materials and additives to the diethyl phosphite reaction device and mixing; S2, stirring, stirring the mixture by a stirring device; S3, temperature control, while stirring, the temperature is controlled by the above-mentioned diethyl phosphite reaction device, and the temperature control includes a heating stage, a heat preservation stage and a cooling stage. During the heating stage, the water inlet pipe is opened to add a certain amount of water to the outer chamber of the heat exchange chamber so that the heating coil is immersed, and then the water in the outer chamber of the heat exchange chamber is heated to boiling by the heating coil to generate water vapor. The generated water vapor first rises and then falls through the annular partition and is discharged through the exhaust pipe; during the heat preservation stage, the valves at the water inlet pipe and the exhaust pipe are opened to continuously introduce constant temperature water into the heat exchange chamber, and the temperature of the introduced water is slightly higher than the reaction temperature until the end of the reaction; at the end of the reaction, as the product concentration increases, water at room temperature is introduced through the water inlet pipe and the drain pipe to cool the kettle; S4, separation, separation of by-products from the reaction mixture; S5, filtering or separating to remove the generated solid residue; S6, purification by distillation, further purifying diethyl phosphite by distillation.

[0028] In step S3, two branches are set at the outer end of the water inlet pipe and the water circuit switching is controlled by an electric three-way mixing valve. One branch is connected to the tap water pipe, and the other branch is connected to the heating water tank and forms a circulating water circuit with the drain pipe. The exhaust pipe discharges the steam or exchanges heat with the heating water tank through the pipeline. During the reaction process, the reaction temperature is controlled by setting a temperature sensor in the kettle body, and then the water source is switched through the two branches of the water inlet pipe to achieve temperature increase or decrease.

[0029] In step S3, during the temperature rising stage, a pressure relief valve is provided at the exhaust pipe, and the pressure in the heat exchange chamber is adjusted by adjusting the pressure of the pressure relief valve, thereby increasing the temperature of the steam and accelerating the temperature rising process.

[0030] It should be noted that temperature sensors are set at the tap water end and in the heating water tank, and a controller is set to connect with each sensor and the controllable control valve. When adjusting the temperature, the opening and closing and opening degree of the control valve can be adjusted. For example, if the temperature in the kettle rises due to heat generated by the reaction during the insulation stage, tap water is introduced at the same time as hot water to neutralize the temperature. Space is reserved in the heating water tank for the addition of tap water for neutralization, or an overflow valve is set to automatically discharge when the water level in the heating water tank is too high. Assume that the tap water flow rate is Q1, the warm water flow rate is Q2, the reaction time is t, the kettle volume is V, T is the temperature to be reached after mixing, T1 is the optimal temperature for the reaction, T2 is the actual temperature in the reactor, and T3 is the temperature required for the heating tank, so that (Q1+Q2)t=V, then Q1 / Q2 = (75-T) / (T-25), where T is the temperature to be reached after mixing, T=T1-|T1-T2|, and Q1 / Q2 represents the opening ratio of the electric three-way mixing valve after adjustment, T3=(25Q1+Q2xT3) / (Q1+Q2).

[0031] In addition, a thermocouple is provided in the heating water tank. When the circulating water flows back, the temperature inside the tank is changed, and the flow rates of Q1 and Q2 are adjusted accordingly. The adjustment frequency is performed in a preset manner.

[0032] The above is a detailed introduction to the titles provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the present invention and its core ideas. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified. These improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A diethyl phosphite reaction apparatus comprising a kettle body and a kettle cover covering the kettle body, wherein the kettle cover is provided with a stirring device extending into the kettle body, characterized in that: The side wall of the kettle body is provided with an annular spacer arranged along the circumference of the kettle body, and an annular heat exchange chamber is formed between the spacer and the kettle body. The middle of the heat exchange chamber is provided with an annular vertical plate whose height is lower than the height of the heat exchange chamber. The annular vertical plate divides the lower part of the heat exchange chamber into an inner chamber and an outer chamber. The side wall of the outer chamber is provided with a water inlet pipe and an exhaust pipe, and a heating coil is provided on the lower side of the outer chamber. The water inlet pipe is located on the lower side of the spacer, and the exhaust pipe is located on the upper side of the spacer and extends to the bottom of the inner chamber of the heat exchange chamber through a pipeline. Control valves are provided at both the water inlet pipe and the exhaust pipe.

2. diethyl phosphite reaction device according to claim 1, is characterized in that, The valves at the exhaust pipe include a pressure relief valve and an electronically controlled valve which are arranged in sequence, wherein the pressure relief valve is a pressure-adjustable pressure relief valve.

3. diethyl phosphite reaction device according to claim 1, is characterized in that, The water inlet pipe is connected to a tee and equipped with an electric three-way mixing valve. One end of the tee is connected to a water supply pipe for adding normal temperature water to the outer chamber, and the other end of the tee is connected to a circulating water pipe for adding temperature-controlled hot water to the outer chamber.

4. diethyl phosphite reaction device according to claim 3, characterized in that, It also includes an external heating water tank, a circulating water pipe is connected to the heating water tank, and a pump is provided at the circulating water pipe.

5. The diethyl phosphite reaction device according to claim 4, wherein A serpentine heat exchange tube is provided in the heating water tank. One end of the heat exchange tube extends above the water surface of the heating water tank and an overflow valve is provided between the water surface and the top opening of the heat exchange tube. The exhaust pipe is provided with two branches, one of which is connected to the heat exchange tube and is provided with an electrically controlled valve, and the other branch is connected to the outside world and is provided with an electrically controlled drain valve.

6. The diethyl phosphite reaction device according to claim 1, characterized in that: The stirring device comprises a stirring motor, a stirring shaft arranged at the output end of the stirring motor and a stirring blade arranged on the stirring shaft. The stirring shaft rotation seal passes through the kettle cover and extends into the kettle body.

7. The diethyl phosphite reaction device according to claim 6, characterized in that: The invention also comprises a controller and a plurality of thermocouples arranged in the kettle body. The control valves, the stirring motor and the thermocouples are all electrically connected to the controller.

8. A process for producing diethyl phosphite, characterized in that: The following steps are involved: S1, adding the raw materials and additives to the diethyl phosphite reaction device according to any one of claims 1-7 and mixing; S2, stirring, stirring the mixture by a stirring device; S3, temperature control: While stirring, the temperature is controlled by the diethyl phosphite reaction device. The temperature control includes a heating stage, a heat preservation stage, and a cooling stage. During the heating stage, a water inlet pipe is opened to add a certain amount of water to the outer chamber of the heat exchange chamber so that the heating coil is immersed. The water in the outer chamber of the heat exchange chamber is then heated to boiling by the heating coil to generate water vapor. The generated water vapor first rises and then falls through the annular partition and is discharged into the heating water tank through the exhaust pipe for heat exchange and discharge. During the insulation stage, the valves at the water inlet and exhaust pipes are opened to continuously introduce constant-temperature water into the heat exchange chamber. The temperature of the introduced water is slightly higher than the reaction temperature until the end of the reaction. During the cooling stage, at the end of the reaction, as the product concentration increases, water at room temperature is introduced through the water inlet and drain pipes to cool the kettle. S4, separation, separation of by-products from the reaction mixture; S5, filtering or separating to remove the generated solid residue; S6, purification by distillation, further purifying diethyl phosphite by distillation.

9. The process for producing diethyl phosphite according to claim 8, wherein In step S3, two branches are set at the outer end of the water inlet pipe and the water circuit switching is controlled by an electric three-way mixing valve. One branch is connected to the tap water pipe, and the other branch is connected to the heating water tank and forms a circulating water circuit with the drain pipe. The exhaust pipe discharges the steam or exchanges heat with the heating water tank through the pipeline. During the reaction process, the reaction temperature is controlled by setting a temperature sensor in the kettle body, and then the water source is switched through the two branches of the water inlet pipe to achieve temperature increase or decrease.

10. The process for producing diethyl phosphite according to claim 9, wherein: In step S3, during the temperature rising stage, a pressure relief valve is provided at the exhaust pipe, and the pressure in the heat exchange chamber is adjusted by adjusting the pressure of the pressure relief valve, thereby increasing the temperature of the steam and accelerating the temperature rising process.

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