CN211445581U

CN211445581U - Be applied to synthetic and device of deacidification of dimethyl phosphite

Info

Publication number: CN211445581U
Application number: CN201922256140.6U
Authority: CN
Inventors: 詹鉴; 蔡林; 孙义; 许长泽; 秦伟
Original assignee: Hubei Taisheng Chemical Co Ltd
Current assignee: Hubei Taisheng Chemical Co Ltd
Priority date: 2019-12-16
Filing date: 2019-12-16
Publication date: 2020-09-08
Anticipated expiration: 2029-12-16

Abstract

The utility model provides a device applied to dimethyl phosphite synthesis and deacidification, wherein a methanol metering tank is connected with a hedging reaction tube through a first pipeline; the phosphorus trichloride metering tank is connected with the hedging reaction pipe through a second pipeline; the hedging reaction pipe is connected with the esterification reactor through a third pipeline; the esterification reactor is connected with a deacidification reactor, and the deacidification reactor is connected with a crude ester container. The methanol metering tank enters from the top inlet of the hedging reaction tube through a first pipeline; the phosphorus trichloride metering tank enters from the side wall inlet of the hedging reaction tube through a second pipeline; and the first pipeline and the second pipeline are converged in the hedging reaction pipe to form a third pipeline, and the third pipeline extends deep to the bottom of the esterification reactor. The sleeve is arranged outside the hedging reaction tube, so that on one hand, the cooling effect can be achieved, on the other hand, the excessive methanol can be ensured, and the production is safer and more stable. Design through designing deacidifying equipment structure in deacidification stage, select for use multistage throwing away a set dispersion materials, promote the deacidification effect. The occurrence of side reactions is reduced.

Description

Be applied to synthetic and device of deacidification of dimethyl phosphite

Technical Field

The utility model belongs to the technical innovation that the alkyl ester method production glyphosate in-process carried out to dimethyl phosphite reaction characteristics, concretely relates to methyl alcohol and phosphorus trichloride hedging reaction, dimethyl phosphite deacidification reaction etc. furthest promotes the yield, reduces the side reaction and takes place.

Background

Dimethyl phosphite is an important chemical intermediate, is a raw material for preparing pesticides such as glyphosate, trichlorfon and the like, and can also be used as a raw material for an organic corrosion inhibitor, a dye additive, a plastic auxiliary agent and a flame retardant. At present, the domestic main production process of glyphosate has two routes: alkyl ester processes and iminodiacetic acid processes. The production process in foreign countries is mainly the iminodiacetic acid method of Monsanto, USA, the mainstream process for producing glyphosate in China is glycine-dialkyl phosphite, in the route, dimethyl phosphite is used as the phosphorus raw material in the synthesis process of glyphosate, therefore, the yield of dimethyl phosphite is efficiently promoted, and the method has important significance for synthesizing glyphosate by the glycine method in China. Dimethyl phosphite is generally prepared by the reaction of phosphorus trichloride and methanol, the reaction is rapid, the heat release is large, and byproducts such as chloromethane, hydrogen chloride and the like are generated at the same time. The reaction process has more side reactions and complex reaction process and conditions, thereby improving the effective conversion rate of the dimethyl phosphite and reducing the occurrence of the side reactions, and having important significance for the agricultural and chemical industry of China.

The main reaction is exothermic reaction, and a large amount of gas (chloromethane and hydrogen chloride) is generated after the two liquid raw materials react. According to the chemical reaction principle, the heat generated by the reaction needs to be removed in the process, and because the hydrogen chloride generated by the reaction can further react with dimethyl phosphite to generate methyl chloride, the generated gas is pumped away as much as possible, the content of the hydrogen chloride in the reaction system is reduced, the occurrence of side reactions is reduced, and the yield of the main product is improved.

At present, during the production process of dimethyl phosphite, methanol and phosphorus trichloride are usually subjected to a hedging tube contact reaction, if the dimethyl phosphite is operated for a long time, the hedging tube deforms and shifts, so that raw materials cannot be subjected to a full contact reaction, the temperature in the reaction process is high, and the like, so that the main reaction process is seriously influenced, and meanwhile, due to the poor material dispersion effect in the deacidification process, the deacidification effect is poor, so that the side reaction is increased, and the yield is reduced.

Disclosure of Invention

The utility model provides a device for dimethyl phosphite is synthetic and deacidification mainly optimizes the reaction process of dashing through esterifying synthetic stage at the front end, and furthest reduces the reaction temperature of methyl alcohol and phosphorus trichloride, ensures the abundant contact of two kinds of materials simultaneously. Simultaneously, in the later deacidification process, the internal structure of the deacidification evaporator is designed, the deacidification reaction effect is improved to the maximum extent, and the occurrence of side reactions is reduced.

A device applied to dimethyl phosphite synthesis and deacidification is characterized in that a methanol metering tank is connected with a hedging reaction tube through a first pipeline;

the phosphorus trichloride metering tank is connected with the hedging reaction pipe through a second pipeline;

the hedging reaction pipe is connected with the esterification reactor through a third pipeline;

the esterification reactor is connected with a deacidification reactor, and the deacidification reactor is connected with a crude ester container.

The methanol metering tank enters from the top inlet of the hedging reaction tube through a first pipeline;

the phosphorus trichloride metering tank enters from the side wall inlet of the hedging reaction tube through a second pipeline;

and the first pipeline and the second pipeline are converged in the hedging reaction pipe to form a third pipeline, and the third pipeline extends deep to the bottom of the esterification reactor.

The methanol metering tank is connected with a methanol condenser through a first pipeline, and the methanol condenser is connected with the hedging reaction tube through a first pipeline.

The part of the first pipeline extending into the hedging reaction tube and the hedging reaction tube are wrapped by a sleeve.

The deacidification reactor in be provided with the speed reducer pivot, be provided with multistage throwing away the dish on the speed reducer pivot.

The throwing disc is in two stages, namely a first-stage throwing disc and a second-stage throwing disc; the primary throwing disk and the secondary throwing disk are both provided with holes with the diameter of 1-10 mu m, wherein the aperture of the holes on the secondary throwing disk is larger than that of the primary throwing disk.

The utility model provides a pair of a device for dimethyl phosphite is synthetic and deacidification, beneficial effect is as follows: 1. can ensure effective contact of materials in the esterification reaction process and avoid insufficient reaction caused by deflection of a pipeline. 2. Because the temperature of the cooled methanol is low, the temperature of the impact reactor can be subjected to heat exchange by using the low-temperature methanol, the reaction temperature is further reduced, and the main reaction is promoted. 3. This offset reaction outside of tubes is equipped with the sleeve pipe, can play the cooling effect on the one hand, and on the other hand can ensure that methyl alcohol is excessive, ensures production safety and stability more. 4. Design through designing deacidifying equipment structure in deacidification stage, select for use multistage throwing away a set dispersion materials, promote the deacidification effect. The occurrence of side reactions is reduced.

Drawings

FIG. 1 shows a device for synthesizing and deacidifying dimethyl phosphite,

FIG. 2 is a schematic view of the structure of a hedging reaction tube.

FIG. 3 is a schematic illustration of the deacidification reactor configuration.

The system comprises a phosphorus trichloride metering tank 1, a methanol metering tank 2, a methanol condenser 3, a hedging reaction tube 4, an esterification reactor 5, a deacidification reactor 6, a pipeline I7, a pipeline II 8, a pipeline III 9, a speed reducer 10, a first-stage throwing disc 11, a second-stage throwing disc 12, a sleeve 13 and a hole 14.

Detailed Description

A device applied to dimethyl phosphite synthesis and deacidification is characterized in that a methanol metering tank 2 is connected with a hedging reaction tube 4 through a first pipeline 7; the phosphorus trichloride metering tank 1 is connected with the hedging reaction tube 4 through a second pipeline 8; the methanol is condensed by the condenser and then flows into the flushing pipe through the sleeve to react with the phosphorus trichloride. Before the methanol enters the flushing pipe to react with the phosphorus trichloride, the deep cooling brine can be selected for cooling, the temperature of the methanol is reduced, and the temperature in the esterification reaction process is further reduced.

The hedging reaction pipe 4 is connected with the esterification reactor 5 through a third pipeline 9;

esterification reactor 5 is connected to deacidification reactor 6, deacidification reactor 6 is connected to the crude ester container.

The methanol metering tank 2 enters from the top inlet of the hedging reaction tube 4 through a first pipeline 7;

the phosphorus trichloride metering tank 1 enters from an inlet on the side wall of the hedging reaction tube 4 through a second pipeline 8;

the first pipeline 7 and the second pipeline 8 are combined in the opposite impact reaction pipe 4 to form a third pipeline 9, and the third pipeline 9 extends to the bottom of the esterification reactor 5.

The methanol metering tank 2 is connected with the methanol condenser 3 through a first pipeline 7, and the methanol condenser 3 is connected with the opposite-impact reaction tube 4 through a first pipeline 7.

The part of the first pipeline 7 extending into the hedging reaction tube 4 and the hedging reaction tube 4 are wrapped by a sleeve 13.

A speed reducer rotating shaft 10 is arranged in the deacidification reactor 6, and a multi-stage throwing disc is arranged on the speed reducer rotating shaft 10.

The throwing disc is in two stages, namely a first-stage throwing disc 11 and a second-stage throwing disc 12; the primary throwing disk 11 and the secondary throwing disk 12 are both provided with holes 14 with the diameter of 1-10 mu m, wherein the hole diameter of the hole on the primary throwing disk 11 is 5 mu m, and the hole diameter of the hole on the secondary throwing disk 12 is 8 mu m.

The model specification of the equipment is as follows, 1. phosphorus trichloride metering tank phi 1200 is 1500, 2. methanol metering tank phi 1200 is 1500, 3. methanol condenser 6m ²4, an opposed reaction tube, 5, an esterification reactor 1000L (chemical engineering in Jingjiang city), 6, a deacidification reactor 2000L, 7, a pipeline I phi 16, 8, a pipeline II phi 16, 9, a pipeline III phi 76, 10, a speed reducer LLD120-I56-5.5, a motor YB2-132S-4-5.5KW, 11, a

primary flail

11, 12, a secondary flail, and 13, a sleeve phi 63 glass tube.

The discharging pipeline of the metering tank for methanol and phosphorus trichloride is respectively communicated with an inlet at the top of an hedging reaction tube (namely an A interface) and an inlet at the side wall (namely a B interface), the hedging reaction tube is inserted into an esterification reactor, a jacket is arranged outside the esterification reactor, the esterification reactor adopts deep cooling brine for cooling, the top of the esterification reactor is connected with a tail gas pipeline and vacuumizes a system, and hydrogen chloride and chloromethane tail gas generated in the reaction process are recovered.

The discharge pipeline at the bottom of the esterification reactor is connected with the deacidification reactor and is inserted into a primary throwing disc of the deacidification reactor, a secondary throwing disc is arranged below the primary throwing disc of the deacidification reactor (the number of the throwing discs and the deacidification condition of crude ester can be adjusted according to actual conditions, a speed reducer and a rotating shaft are arranged on the deacidification reactor, and a two-stage throwing disc is arranged on the rotating shaft). And a secondary throwing disc is arranged below the primary throwing disc, and crude ester which is not fully atomized or is overflowed by the primary throwing disc flows to the secondary throwing disc for deacidification. Ensure the formation of a mist liquid film and enhance the deacidification and evaporation effects to the maximum extent.

The deacidification reactor can be provided with two stages, the number of the internal throwing discs can be adjusted according to actual conditions, a discharge pipeline at the bottom of the deacidification reactor is connected with a crude ester storage tank container, and a product is obtained and then enters a refining and purifying process.

And the top of the deacidification reaction kettle is connected with a tail gas pipeline, and the system is vacuumized. The bottom is connected with a crude ester container, and the deacidified material is filled into the crude ester container and finally purified in the crude ester refining process.

Claims

1. A device applied to dimethyl phosphite synthesis and deacidification is characterized in that a methanol metering tank (2) is connected with a hedging reaction tube (4) through a pipeline I (7);

the phosphorus trichloride metering tank (1) is connected with the hedging reaction tube (4) through a second pipeline (8);

the hedging reaction tube (4) is connected with the esterification reactor (5) through a third pipeline (9);

the esterification reactor (5) is connected with a deacidification reactor (6), and the deacidification reactor (6) is connected to a crude ester container.

2. The apparatus for the synthesis and deacidification of dimethyl phosphite according to claim 1, wherein the methanol metering tank (2) is entered from the top inlet of the hedging reaction tube (4) through the first pipe (7);

the phosphorus trichloride metering tank (1) enters from an inlet on the side wall of the hedging reaction tube (4) through a second pipeline (8);

the first pipeline (7) and the second pipeline (8) are combined in the hedging reaction tube (4) to form a third pipeline (9), and the third pipeline (9) extends to the bottom of the esterification reactor (5).

3. The apparatus for the synthesis and deacidification of dimethyl phosphite according to claim 2, wherein the methanol metering tank (2) is connected with the methanol condenser (3) through the first pipe (7), and the methanol condenser (3) is connected with the opposite flushing reaction pipe (4) through the first pipe (7).

4. The device for the synthesis and deacidification of dimethyl phosphite according to claim 3, wherein the portion of the first pipeline (7) extending into the opposite flushing reaction tube (4) and the opposite flushing reaction tube (4) are wrapped by the sleeve (13).

5. The device for the synthesis and deacidification of dimethyl phosphite according to claim 3, wherein a speed reducer rotating shaft (10) is arranged in the deacidification reactor (6), and a multi-stage throwing disc is arranged on the speed reducer rotating shaft (10).

6. The apparatus for the synthesis and deacidification of dimethyl phosphite according to claim 5, wherein the flail disk is two-stage, i.e. a first-stage flail disk (11) and a second-stage flail disk (12); the primary throwing disc (11) and the secondary throwing disc (12) are both provided with holes (14) with the diameter of 1-10 mu m, wherein the aperture of the holes (14) on the secondary throwing disc (12) is larger than that of the primary throwing disc.