Unlock instant, AI-driven research and patent intelligence for your innovation.

Dehydration technology of multi-water sodium sulfide in polyphenylene sulfide production

A technology of sodium sulfide and polyphenylene sulfide, applied in the field of polyphenylene sulfide production process improvement, can solve the problems of increasing construction investment and operating site space, and not prompting the real dehydration process of polyphenylene sulfide resin synthesis. , to avoid energy consumption, save on-site space, and avoid the waste of raw materials

Active Publication Date: 2014-05-07
四川得阳特种新材料有限公司
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The conventional method is to establish a special dehydration facility for dehydration, which increases the construction investment and operating site space on the one hand, and requires additional energy consumption on the other hand.
[0003] In Chinese Patent Application No. CN00116141.5, a method for dehydrating sodium polyhydrate in the production of polyphenylene sulfide is introduced, which is an indispensable process step in the synthesis process of polyphenylene sulfide resin. However, due to the process control index and There are many deficiencies in the specific treatment method. In addition, the patent does not prompt people to synthesize the real dehydration process of polyphenylene sulfide resin.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Dehydration technology of multi-water sodium sulfide in polyphenylene sulfide production
  • Dehydration technology of multi-water sodium sulfide in polyphenylene sulfide production

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0014] In a 25 liter reactor, add Na 2 S.3H 2 4 kg each of O and NMP, 1.2 kg of catalyst LiCl, heated to 180 ° C, and kept at this temperature, the system was azeotropic for about 3 hours, and the amount of water removed was controlled by the infrared online detection system to keep the water content in the system at 1.1 mol / molNa 2 Between S, the crystal water of polyhydric sodium sulfide escapes with water vapor, and at the same time, part of NMP and hydrogen sulfide gas is formed to form a mixed gas containing water vapor, NMP and hydrogen sulfide gas, and the mixed gas is input into normal pressure The rectification tower is separated, and the water vapor flowing out from the top of the rectification tower is cooled and recovered for polyphenylene sulfide washing in the subsequent section; the hydrogen sulfide gas flowing out of the middle and upper parts is absorbed and reused by lye or ammonia water ; The N-methylpyrrolidone solvent flowing out from the bottom is purif...

Embodiment 2

[0016] In the 25 liter reactor, add Na 2 S.9H 2 4.7 kg of O and 4 kg of NMP, 1.2 kg of catalyst LiCl, heated to 204 ° C to maintain the temperature, and the system was azeotropic for about 2 hours. The amount of water removed was controlled by the infrared online detection system to keep the water content in the system at 1.2 mol / molNa 2 Between S, the crystal water of polyhydric sodium sulfide escapes with water vapor, and at the same time, part of NMP and hydrogen sulfide gas is formed to form a mixed gas containing water vapor, NMP and hydrogen sulfide gas, and the mixed gas is input into normal pressure The rectification tower is separated, and the water vapor flowing out from the top of the rectification tower is cooled and recovered for polyphenylene sulfide washing in the subsequent section; the hydrogen sulfide gas flowing out of the middle and upper parts is absorbed and reused by lye or ammonia water ; The N-methylpyrrolidone solvent flowing out from the bottom is...

Embodiment 3

[0018] In the 25 liter reactor, add Na 2 S.9H 2 O 4.7 kg and NMP 4 kg, catalyst LiCl 1.2 kg, pressure heated to 200 ° C, maintain the temperature, the system is azeotropic for about 2.5 hours, and the amount of water removed is controlled by the infrared online detection system to keep the water content in the system at 1.15 mol / molNa 2 Between S, the crystal water of polyhydric sodium sulfide escapes with water vapor, and at the same time, part of NMP and hydrogen sulfide gas is formed to form a mixed gas containing water vapor, NMP and hydrogen sulfide gas, and the mixed gas is input into normal pressure The rectification tower is separated, and the water vapor flowing out from the top of the rectification tower is cooled and recovered for polyphenylene sulfide washing in the subsequent section; the hydrogen sulfide gas flowing out of the middle and upper parts is absorbed and reused by lye or ammonia water ; The N-methylpyrrolidone solvent flowing out from the bottom is p...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a dehydration technology of multi-water sodium sulfide?in a polyphenylene sulfide production. The technology uses the multi-water sodium sulfide and p-dichlorobenzene as raw materials to produce the polyphenylene sulfide through sodium sulfide dehydration, polycondensation and other steps. During the dehydration stage of the multi-water sodium sulfide, an infrared on-line detection system is used to control removed amount of the water, so that the moisture in the system is kept between 1.1-1.2 mol / mol Na2S. The multi-water sodium sulfide?and an NMP solution are heated to boil in a reactor under a temperature of 180 to 240 DEG C, so that crystal water of the sodium sulfide is removed in a form of water vapor. The water vapor, N-methylpyrrolidone and hydrogen sulfide gas generated during the dehydration process are separated through a normal-pressure rectifying tower. The technology provided by the invention, for one hand, simplifies technology equipment and saves on-site space, and for the other hand, maintains relatively stable heating systems for dehydration and condensation polymerization, thereby preventing additional energy consumption and waste of raw materials.

Description

technical field [0001] The invention relates to the improvement of the production process of polyphenylene sulfide. Background technique [0002] In the process of producing polyphenylene sulfide monomer (PPS) by using alkali metal sulfide and p-dichlorobenzene as raw materials through processes such as sodium sulfide dehydration and polycondensation, because alkali metal sulfide often has crystal water that needs to be removed, for This requires dehydration before adding p-dichlorobenzene for polycondensation. The conventional method is to establish a special dehydration facility for dehydration, which increases the construction investment and operating site space on the one hand, and requires additional energy consumption on the other hand. [0003] In Chinese Patent Application No. CN00116141.5, a method for dehydrating sodium polyhydrate in the production of polyphenylene sulfide is introduced, which is an indispensable process step in the synthesis process of polypheny...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C08G75/02C08G75/0213C08G75/0254
Inventor 徐伟王鑫
Owner 四川得阳特种新材料有限公司