Method for solvent recovery in polyphenylene sulfide synthesis process

A synthesis process, polyphenylene sulfide technology, applied in the field of solvent recovery in the polyphenylene sulfide synthesis process, can solve problems affecting energy consumption, adverse effects, and complicated operation procedures, so as to improve recovery rate, reduce energy consumption and material consumption Effect

Active Publication Date: 2013-10-02
CHINA PETROLEUM & CHEM CORP
View PDF0 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method has three disadvantages: first, use other organic solvents for washing, and the operation process is relatively complicated; second, the solvent recovery rate is low; third, when washing products with water, the washing liquid contains solvents and a large amount of salt, and the recovery of solvents High energy consumption and high requirements on the material of distillation and rectification equipment, high recovery cost
Since the product contains a large amount of by-product salt, after the product is washed with water, the washing liquid will contain a large amount of salt, and the washing liquid will enter the rectification tower, causing adverse effects and affecting energy consumption

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0016] Add 300KG N-methylpyrrolidone into a 500L reactor to carry out the synthesis reaction. After the reaction, the centrifuge was used for centrifugation, and the material temperature was 50°C during separation. The product is subjected to 6 water washes. The first three washes and the centrifuged filtrate are distilled together in a distillation tower under reduced pressure, and the N-methylpyrrolidone collected by distillation is added to the rectification tower for rectification under reduced pressure to obtain a colorless solvent N-methylpyrrolidone with a purity of 99.9%. , the output is 240KG, and the recovery rate is 80%.

Embodiment 2

[0018] Add 300KG N-methylpyrrolidone into a 500L reactor to carry out the synthesis reaction. After the reaction is finished, separate with a filter press, and the material temperature is 50° C. during separation. Wash the product 3 times with alcohol and then wash it with water 3 times. The filtrate from alcohol washing and centrifugal separation is distilled under reduced pressure in the distillation tower together, and the water washing liquid is distilled separately to collect ethanol. The N-methylpyrrolidone collected by distillation was added to a rectification tower and rectified under reduced pressure to obtain N-methylpyrrolidone, a colorless solvent, with a purity of 99.9%, a yield of 255KG, and a recovery rate of 85%.

Embodiment 3

[0020] Add 300KG N-methylpyrrolidone into a 500L reactor to carry out the synthesis reaction. After the reaction, the centrifuge was used for centrifugation, and the material temperature was 60°C during separation. After centrifugation, the filter cake was added to a vacuum double-cone rotary dryer for drying under reduced pressure. The temperature was controlled at 110° C., the vacuum degree was -0.097 MPa, and the drying time was 12 hours. The weight of the product before drying is 160KG, and the weight of the product after drying is 101KG. The moisture content of the product after drying is 1%. The condenser condenses and collects 59KG of solvent N-methylpyrrolidone. The 239KG filtrate after centrifugation and the solvent N-methylpyrrolidone collected by drying and condensation were added to the rectification tower for vacuum distillation to obtain a colorless solvent with a purity of 99.9%, a yield of 283KG, and a recovery rate of 94.3%.

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 provides a method for solvent recovery in a polyphenylene sulfide synthesis process. The method includes: subjecting a synthesis reaction generated product to solid-liquid separation by a centrifugal machine or filter press at 40-80DEG C; drying the solid product by a vacuum double-cone rotary dryer or a vacuum rake dryer at 100-150DEG C and under an operation pressure of not greater than -0.096MPa, using condensed water to conduct condensation at normal temperature to recover a solvent; and sending the recovered solvent and the filtrate obtained from solid-liquid separation directly to a rectifying tower to undergo rectification treatment. The method provided in the invention adopts vacuum drying equipment to dry the separated reaction product, and directly recovers the solvent, thus avoiding other solvent washing and water washing in commonly used solvent recovery methods, greatly reducing energy consumption and material consumption, and improving the solvent recovery rate.

Description

technical field [0001] The invention relates to the technical field of solvent recovery, in particular to a solvent recovery method in a polyphenylene sulfide synthesis process. Background technique [0002] At present, the most commonly used route for the synthesis of polyphenylene sulfide is the sodium sulfide method, and a large amount of solvent is used in the synthesis process. At present, the commonly used route for solvent recovery is: after the synthesis reaction is completed, the reaction liquid is subjected to solid-liquid separation, and then the separated solid is washed repeatedly with other organic solvents and water to remove by-product salts, and the washing liquid enters the distillation tower and The rectification column performs solvent recovery. This method has three disadvantages: first, use other organic solvents for washing, and the operation process is relatively complicated; second, the solvent recovery rate is low; third, when washing products with...

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 Applications(China)
IPC IPC(8): C08J11/02
Inventor 杨雨强张志全李荣苑娜娟
Owner CHINA PETROLEUM & CHEM CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap