Energy-saving method for separating methylbenzene and 2-methoxyethanol mixture by extractive distillation

A methoxyethanol and extractive distillation technology is applied in the energy saving field of extractive distillation and separation of a mixture of toluene and 2-methoxyethanol, and can solve the problems of low product purity of toluene, low product purity and yield, and high energy consumption

Inactive Publication Date: 2018-01-19
EAST CHINA UNIV OF SCI & TECH
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Li et al. (Computers&Chemical Engineering, 2017,99:117.) designed the process of extractive distillation to separate toluene and 2-methoxyethanol, but the product purity and yield are low, and the process consumes a lot of energy
Sun Chang (Research on the separation of toluene / ethylene glycol monomethyl ether by batch extraction and rectification [D]. Tianjin University, 2013.) designed a process for the separation of toluene and 2-methoxyethanol by batch extraction and rectification, but the reflux ratio is extremely Large (9) and the toluene product has a low purity, only 98.8%, and has the disadvantages of high energy consumption and low product purity

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
  • Energy-saving method for separating methylbenzene and 2-methoxyethanol mixture by extractive distillation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Take 8411.8kg / h of toluene content as 54.8wt% toluene and 2-methoxyethanol mixture as example:

[0026] The extractive distillation column has a total of 40 trays, the reflux ratio is 0.89, and the operating pressure is 1atm. The fresh material enters the extractive distillation column from the 29th tray, and the flow rate of the extractant (dimethyl sulfoxide) is 5860.1kg / h The rate (molar ratio is 0.75) enters the extractive distillation column from the 8th tray. The temperature at the top of the extractive distillation column is 110.7°C, the heat load of the condenser is 0.88MW, the temperature at the bottom of the tower is 155.3°C, and the heat load of the supplementary reboiler is 1.04MW. The extraction agent recovery tower has a total of 20 trays, the reflux ratio is 0.81, and the operating pressure is 3.3 atm. The mixed solution of 2-methoxyethanol and extractant enters the extraction agent recovery tower from the eighth tray, and the extraction agent recovery to...

Embodiment 2

[0028] Take 8411.8kg / h of toluene content as 54.8wt% toluene and 2-methoxyethanol mixture as example:

[0029] There are 35 trays in the extractive distillation column, the reflux ratio is 1.18, and the operating pressure is 0.8atm. The fresh material enters the extractive distillation column from the 25th tray, and the flow rate of the extractant (dimethyl sulfoxide) is 6250.8kg / The rate of h (molar ratio is 0.80) enters the extractive distillation column from the 8th tray. The temperature at the top of the extractive distillation column is 103.0°C, the heat load of the condenser is 1.03MW, the temperature at the bottom of the column is 148.5°C, and the heat load of the supplementary reboiler is 0.69MW. The extraction agent recovery tower has a total of 15 trays, the reflux ratio is 1.70, and the operating pressure is 3.0atm. The mixed solution of 2-methoxyethanol and extractant enters the extraction agent recovery tower from the sixth tray, and the extraction agent recovery...

Embodiment 3

[0031] Take 8411.8kg / h of toluene content as 54.8wt% toluene and 2-methoxyethanol mixture as example:

[0032]There are 30 trays in the extractive distillation column, the reflux ratio is 1.63, and the operating pressure is 0.5atm. The fresh material enters the extractive distillation column from the 21st tray, and the flow rate of the extractant (dimethyl sulfoxide) is 8204.2kg / The rate of h (molar ratio is 1.05) enters the extractive distillation column from the 7th tray. The temperature at the top of the extractive distillation column is 88.0°C, the heat load of the condenser is 1.27MW, the temperature at the bottom of the tower is 137.1°C, and the heat load of the supplementary reboiler is 0.61MW. The extraction agent recovery tower has a total of 10 trays, the reflux ratio is 2.20, and the operating pressure is 2.0atm. The mixed solution of 2-methoxyethanol and extractant enters the extraction agent recovery tower from the sixth tray, and the extraction agent recovery to...

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 an energy-saving method for separating a methylbenzene and 2-methoxyethanol mixture by extractive distillation. An extracting agent for the energy-saving method is dimethyl sulfoxide; the used separating equipment comprises an extractive distillation column, a heat exchanger and an extracting agent recovering tower; in the separating process, methylbenzene steam generated on the top of the extractive distillation column is condensed and then is extracted according to the preset reflux ratio; 2-methoxyethanol and the extracting agent at the bottom of the extractive distillation column are extracted and then are divided into a circulating material flow and a discharging material flow; the circulating material flow is heated by the heat exchanger and then returns to enter the extractive distillation column; the discharging material flow enters the extractive distillation column; the extracting agent is extracted from the bottom of the extracting agent recovering tower and is recycled; and 2-methoxyethanol steam generated on the top of the extracting agent recovering tower is condensed by the heat exchanger and then is extracted according to the preset reflux ratio. According to the method, a double-effect heat-integration technique is adopted, and heat is provided for to-be-reboiled material flow at the bottom of the extractive distillation column by usinga to-be-condensed material flow on the top of the extracting agent recovering tower, so that secondary utilization of energy is realized, energy consumption is effectively reduced and the cost of equipment is reduced.

Description

technical field [0001] The invention belongs to the technical field of extraction, rectification and separation, and relates to a method for separating a mixture of toluene and 2-methoxyethanol, in particular to an energy-saving method for separating the mixture of toluene and 2-methoxyethanol through extraction and rectification. Background technique [0002] Toluene is an extremely important synthetic raw material and organic solvent in the chemical industry. As a raw material, it is used to prepare chemicals such as benzene and xylene, and can also be used in the production of fine chemicals such as spices. It is widely used in chemical, pharmaceutical, pigment and synthetic material industries. As a solvent, it is used in printing and dyeing, coating and electrochemical industries. 2-Methoxyethanol is mainly used as a solvent for oils, nitrocellulose, synthetic resins, alcohol-soluble dyes, etc., as well as a pesticide dispersant and a leather plasticizer. In the above...

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): C07C7/08C07C15/06C07C41/42C07C43/13
CPCY02P20/10Y02P20/50
Inventor 尤新强朱雨航彭昌军刘洪来
Owner EAST CHINA UNIV OF SCI & TECH
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