CN105294498A - Production method for n-butyl isocyanate - Google Patents

Abstract

The invention provides a production method for n-butyl isocyanate. The production method comprises the following steps that a xylene solution is added into a reaction kettle, and n-butylamine steam is introduced into the xylene solution in the reaction kettle; phosgene is introduced into the xylene solution; the phosgene is continuously introduced into the reaction kettle; the temperature of the reaction kettle is lowered, and nitrogen is introduced into the reaction kettle for gas driving. According to the production technology, the purity of an n-butylamine intermediate of the n-butyl isocyanate can be increased, so that the yield can be increased by 10%-20%, wherein the purity of the n-butylamine is increased to 75.9%-80.5%; in addition, the efficiency is improved, the phenomenon that the production efficiency and purity of the n-butyl isocyanate are influenced due to the fact that the n-butylamine has too many impurities is avoided, and by-products are few.

Description

The production method of n-butyl isocyanate

Technical field

The present invention relates to plastics fine chemistry industry production field, be specifically related to the production method of n-butyl isocyanate.

Background technology

Sterling n-butyl isocyanate (C ₄h ₉nCO) be colourless transparent liquid, have strong and stimulating to skin, respiratory mucosa, eyes, can cause and burn, its steam and air can form explosive mixture, meet naked light, high thermoae easy firing blast.

N-butyl isocyanate chemical property is active, important industrial chemicals, is mainly used in sterilant such as synthesis IPBC, F-1991 etc., is also used as the catalyzer of sulfonylurea herbicide synthesis, can be used as the products such as synthesis medicine, agricultural chemicals.Traditional technology adds in reactor by n-Butyl Amine 99, orthodichlorobenzene, pass into excess phosgene at 110 ~ 160 DEG C, become clearly to solution and pass into phosgene again 20 ~ 30 minutes, logical complete, distillation collection 160 DEG C with front-end volatiles, then obtains n-butyl isocyanate through distillation collection 106 ~ 120 DEG C of cuts.

But the n-butyl isocyanate that the synthetic method of traditional n-butyl isocyanate is produced exists, and makes subsequent reactions yield reduce, affects the problem of quality product.

Summary of the invention

For above problems of the prior art, the invention provides the production method of n-butyl isocyanate, improve n-butyl isocyanate output.

The present invention is achieved by the following technical solutions:

The production method of n-butyl isocyanate, its step is as follows:

1) add xylene solution by reactor, the n-Butyl Amine 99 steam of 80-100 DEG C is passed in the xylene solution in reactor, constantly stir after 30-45 minute, and constantly pass into n-Butyl Amine 99 steam;

2) phosgene is passed in the xylene solution in step 1, and by temperature slow cooling to 30-35 DEG C, the maintenance reaction times is 20-30 minute, stops passing into phosgene; Again by the temperature slow cooling in reactor to 0-10 DEG C, keep reaction times 45-60 minute, then by the temperature slow cooling in reactor to-10-0 DEG C, the maintenance reaction times is 30-45 minute;

3) continue in reactor, pass into stopping in phosgene 20-30 minute, reactor temperature slowly can be warming up to 100-110 DEG C, and carry out constantly stirring in reactor, the reaction times is 30-45 minute, continue to be warming up to 110-130 DEG C by reactor, the reaction times is 40-55 minute again;

4) temperature of the reactor of step 3 is cooled to 50-60 DEG C, leaves standstill after 30-45 minute, in reactor, pass into nitrogen catch up with gas.

Further, its step is as follows:

1) add xylene solution by reactor, the n-Butyl Amine 99 steam of 80 DEG C is passed in the xylene solution in reactor, constantly stir after 45 minutes, and constantly pass into n-Butyl Amine 99 steam;

2) phosgene is passed in the xylene solution in step 1, and by temperature slow cooling to 30 DEG C, keeps the reaction times to be 30 minutes, stop passing into phosgene; Again by the temperature slow cooling to 0 DEG C in reactor, keep 45 minutes reaction times, then by the temperature slow cooling in reactor to-10 DEG C, keep the reaction times to be 30 minutes;

3) continue in reactor, pass into phosgene to stop for 20 minutes, reactor temperature slowly can be warming up to 100 DEG C, and carry out constantly stirring in reactor, the reaction times is 45 minutes, then continues to be warming up to 110 DEG C in reactor, and the reaction times is 55 minutes;

4) temperature of the reactor of step 3 is cooled to 50 DEG C, leaves standstill after 45 minutes, in reactor, pass into nitrogen catch up with gas.

Beneficial effect of the present invention is: the present invention adopts above-mentioned production technique, the purity of n-butyl isocyanate can be improved, make yield improve 30-35%, and improve efficiency simultaneously, avoid because by product is too many and affect production efficiency and the purity of n-butyl isocyanate.

Embodiment

In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with embodiment, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.

Embodiment 1

First add xylene solution by reactor, the n-Butyl Amine 99 steam of 80 DEG C is passed in the xylene solution in reactor, constantly stirs after 45 minutes, and constantly pass into n-Butyl Amine 99 steam, the n-Butyl Amine 99 of gas first can be dissolved in xylene solution like this, improve the efficiency of W-response;

Again phosgene is passed in xylene solution, and by temperature slow cooling to 30 DEG C, keeps the reaction times to be 30 minutes, stop passing into phosgene; Again by the temperature slow cooling to 0 DEG C in reactor, keep 45 minutes reaction times, then by the temperature slow cooling in reactor to-10 DEG C, the reaction times is kept to be 30 minutes, the time of reaction can be reduced, reduce the generation of ureas by product, improve the generation of intermediate product;

Again continue in reactor, pass into phosgene to stop for 20 minutes, reactor temperature slowly can be warming up to 100 DEG C, and carry out constantly stirring in reactor, reaction times is 45 minutes, then continues to be warming up to 110 DEG C in reactor, and the reaction times is 55 minutes, the conversion of intermediate product can be improve, reduce the generation of side reaction, control the good reaction times, the output of product can be improved;

Finally the temperature of reactor is cooled to 50 DEG C, leaves standstill after 45 minutes, in reactor, pass into nitrogen catch up with gas, can carry out catching up with light, obtain mixing liquid, finally carry out refining purification and can obtain the higher product of purity.

The present invention adopts above-mentioned production technique, the purity of n-butyl isocyanate can be improved, make yield improve 30%, and improve efficiency simultaneously, avoids because by product is too many and affect production efficiency and the purity of n-butyl isocyanate.

Embodiment 2

First add xylene solution by reactor, the n-Butyl Amine 99 steam of 85 DEG C is passed in the xylene solution in reactor, constantly stirs after 40 minutes, and constantly pass into n-Butyl Amine 99 steam, the n-Butyl Amine 99 of gas first can be dissolved in xylene solution like this, improve the efficiency of W-response;

Again phosgene is passed in xylene solution, and by temperature slow cooling to 31 DEG C, keeps the reaction times to be 28 minutes, stop passing into phosgene; Again by the temperature slow cooling to 2 DEG C in reactor, keep 50 minutes reaction times, then by the temperature slow cooling in reactor to-8 DEG C, the reaction times is kept to be 35 minutes, the time of reaction can be reduced, reduce the generation of ureas by product, improve the generation of intermediate product;

Again continue in reactor, pass into phosgene to stop for 24 minutes, reactor temperature slowly can be warming up to 102 DEG C, and carry out constantly stirring in reactor, reaction times is 40 minutes, then continues to be warming up to 115 DEG C in reactor, and the reaction times is 50 minutes, the conversion of intermediate product can be improve, reduce the generation of side reaction, control the good reaction times, the output of product can be improved;

Finally the temperature of reactor is cooled to 52 DEG C, leaves standstill after 40 minutes, in reactor, pass into nitrogen catch up with gas, can carry out catching up with light, obtain mixing liquid, finally carry out refining purification and can obtain the higher product of purity.

The present invention adopts above-mentioned production technique, the purity of n-butyl isocyanate can be improved, make yield improve 31%, and improve efficiency simultaneously, avoids because by product is too many and affect production efficiency and the purity of n-butyl isocyanate.

Embodiment 3

First add xylene solution by reactor, the n-Butyl Amine 99 steam of 90 DEG C is passed in the xylene solution in reactor, constantly stirs after 38 minutes, and constantly pass into n-Butyl Amine 99 steam, the n-Butyl Amine 99 of gas first can be dissolved in xylene solution like this, improve the efficiency of W-response;

Again phosgene is passed in xylene solution, and by temperature slow cooling to 33 DEG C, keeps the reaction times to be 25 minutes, stop passing into phosgene; Again by the temperature slow cooling to 4 DEG C in reactor, keep 55 minutes reaction times, then by the temperature slow cooling in reactor to-6 DEG C, the reaction times is kept to be 40 minutes, the time of reaction can be reduced, reduce the generation of ureas by product, improve the generation of intermediate product;

Again continue in reactor, pass into phosgene to stop for 26 minutes, reactor temperature slowly can be warming up to 104 DEG C, and carry out constantly stirring in reactor, reaction times is 38 minutes, then continues to be warming up to 120 DEG C in reactor, and the reaction times is 48 minutes, the conversion of intermediate product can be improve, reduce the generation of side reaction, control the good reaction times, the output of product can be improved;

Finally the temperature of reactor is cooled to 54 DEG C, leaves standstill after 38 minutes, in reactor, pass into nitrogen catch up with gas, can carry out catching up with light, obtain mixing liquid, finally carry out refining purification and can obtain the higher product of purity.

The present invention adopts above-mentioned production technique, the purity of n-butyl isocyanate can be improved, make yield improve 32%, and improve efficiency simultaneously, avoids because by product is too many and affect production efficiency and the purity of n-butyl isocyanate.

Embodiment 4

First add xylene solution by reactor, the n-Butyl Amine 99 steam of 95 DEG C is passed in the xylene solution in reactor, constantly stirs after 35 minutes, and constantly pass into n-Butyl Amine 99 steam, the n-Butyl Amine 99 of gas first can be dissolved in xylene solution like this, improve the efficiency of W-response;

Again phosgene is passed in xylene solution, and by temperature slow cooling to 34 DEG C, keeps the reaction times to be 23 minutes, stop passing into phosgene; Again by the temperature slow cooling to 6 DEG C in reactor, keep 58 minutes reaction times, then by the temperature slow cooling in reactor to-2 DEG C, the reaction times is kept to be 42 minutes, the time of reaction can be reduced, reduce the generation of ureas by product, improve the generation of intermediate product;

Again continue in reactor, pass into phosgene to stop for 28 minutes, reactor temperature slowly can be warming up to 106 DEG C, and carry out constantly stirring in reactor, reaction times is 35 minutes, then continues to be warming up to 125 DEG C in reactor, and the reaction times is 45 minutes, the conversion of intermediate product can be improve, reduce the generation of side reaction, control the good reaction times, the output of product can be improved;

Finally the temperature of reactor is cooled to 58 DEG C, leaves standstill after 35 minutes, in reactor, pass into nitrogen catch up with gas, can carry out catching up with light, obtain mixing liquid, finally carry out refining purification and can obtain the higher product of purity.

The present invention adopts above-mentioned production technique, the purity of n-butyl isocyanate can be improved, make yield improve 34%, and improve efficiency simultaneously, avoids because by product is too many and affect production efficiency and the purity of n-butyl isocyanate.

Embodiment 5

First add xylene solution by reactor, the n-Butyl Amine 99 steam of 100 DEG C is passed in the xylene solution in reactor, continuous stirring is after 30 minutes, and constantly pass into n-Butyl Amine 99 steam, the n-Butyl Amine 99 of gas first can be dissolved in xylene solution like this, improve the efficiency of W-response;

Again phosgene is passed in xylene solution, and by temperature slow cooling to 35 DEG C, keeps the reaction times to be 20 minutes, stop passing into phosgene; Again by the temperature slow cooling to 10 DEG C in reactor, keep 60 minutes reaction times, then by the temperature slow cooling to 0 DEG C in reactor, the reaction times is kept to be 45 minutes, the time of reaction can be reduced, reduce the generation of ureas by product, improve the generation of intermediate product;

Again continue in reactor, pass into phosgene to stop for 30 minutes, reactor temperature slowly can be warming up to 110 DEG C, and carry out constantly stirring in reactor, reaction times is 30 minutes, then continues to be warming up to 130 DEG C in reactor, and the reaction times is 40 minutes, the conversion of intermediate product can be improve, reduce the generation of side reaction, control the good reaction times, the output of product can be improved;

Finally the temperature of reactor is cooled to 60 DEG C, leaves standstill after 30 minutes, in reactor, pass into nitrogen catch up with gas, can carry out catching up with light, obtain mixing liquid, finally carry out refining purification and can obtain the higher product of purity.

The present invention adopts above-mentioned production technique, the purity of n-butyl isocyanate can be improved, make yield improve 30-35%, and improve efficiency simultaneously, avoids because by product is too many and affect production efficiency and the purity of n-butyl isocyanate.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any amendments done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within protection scope of the present invention.

Claims (2)

1. the production method of n-butyl isocyanate, is characterized in that: its step is as follows:

1) add xylene solution by reactor, the n-Butyl Amine 99 steam of 80-100 DEG C is passed in the xylene solution in reactor, constantly stir after 30-45 minute, and constantly pass into n-Butyl Amine 99 steam;

2) phosgene is passed in the xylene solution in step 1, and by temperature slow cooling to 30-35 DEG C, the maintenance reaction times is 20-30 minute, stops passing into phosgene; Again by the temperature slow cooling in reactor to 0-10 DEG C, keep reaction times 45-60 minute, then by the temperature slow cooling in reactor to-10-0 DEG C, the maintenance reaction times is 30-45 minute;

3) continue in reactor, pass into stopping in phosgene 20-30 minute, reactor temperature slowly can be warming up to 100-110 DEG C, and carry out constantly stirring in reactor, the reaction times is 30-45 minute, continue to be warming up to 110-130 DEG C by reactor, the reaction times is 40-55 minute again;

4) temperature of the reactor of step 3 is cooled to 50-60 DEG C, leaves standstill after 30-45 minute, in reactor, pass into nitrogen catch up with gas.

2. the production method of n-butyl isocyanate according to claim 1, is characterized in that: its step is as follows:

1) add xylene solution by reactor, the n-Butyl Amine 99 steam of 80 DEG C is passed in the xylene solution in reactor, constantly stir after 45 minutes, and constantly pass into n-Butyl Amine 99 steam;

2) phosgene is passed in the xylene solution in step 1, and by temperature slow cooling to 30 DEG C, keeps the reaction times to be 30 minutes, stop passing into phosgene; Again by the temperature slow cooling to 0 DEG C in reactor, keep 45 minutes reaction times, then by the temperature slow cooling in reactor to-10 DEG C, keep the reaction times to be 30 minutes;

3) continue in reactor, pass into phosgene to stop for 20 minutes, reactor temperature slowly can be warming up to 100 DEG C, and carry out constantly stirring in reactor, the reaction times is 45 minutes, then continues to be warming up to 110 DEG C in reactor, and the reaction times is 55 minutes;

4) temperature of the reactor of step 3 is cooled to 50 DEG C, leaves standstill after 45 minutes, in reactor, pass into nitrogen catch up with gas.