Method for crystallizing and separating para xylene

A technology for p-xylene and crystallization separation, applied in crystallization purification/separation, organic chemistry, etc., can solve the problems of complex operation and high investment in xylene, and achieve the effect of cheap price, low investment and easy operation

Inactive Publication Date: 2010-06-16
CHINA PETROLEUM & CHEM CORP +1
View PDF8 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is the problem of high investment and complicated operation of adsorption, separation and purification of p-xylene in the prior art, and a new method for crystallization and separation of p-xylene is provided

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
  • Method for crystallizing and separating para xylene
  • Method for crystallizing and separating para xylene

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0015] according to figure 1 As shown, the mixed xylene raw materials are sent to the scraping wall crystallizer, and the crystallization temperature is -10°C to form a slurry. The slurry is sent to a hydraulic tower scrubber for filtration, washing and crystal purification. The washing liquid / crystal With a weight ratio of 0.2, pure p-xylene was obtained. After the test runs stably, the composition of each stream is shown in Table 1.

[0016] The composition (% by weight) of each stream in the embodiment 1 of table 1

[0017] component

Embodiment 2

[0019] according to figure 1 As shown, the mixed xylene raw material is sent to the stirring crystallizer, and the crystallization temperature is -60°C, and the slurry is sent to the gravity tower scrubber, and after filtration, washing and crystal purification, the washing liquid / crystal weight ratio is 0.5, Pure p-xylene was obtained. After the test runs stably, the composition of each stream is shown in Table 2.

[0020] The composition (% by weight) of each stream in the embodiment 2 of table 2

[0021] component

Embodiment 3

[0023] according to figure 1 As shown, the mixed xylene raw materials are sent to the scraping wall crystallizer, and the crystallization temperature is 5°C to form a slurry. The slurry is sent to a mechanical tower scrubber for filtration, washing and crystal purification. The washing liquid / crystal With a weight ratio of 0.05, pure p-xylene was obtained. After the test runs stably, the composition of each stream is shown in Table 3.

[0024] The composition (% by weight) of each stream in the embodiment 3 of table 3

[0025] component

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 relates to a method for crystallizing and separating para xylene, and mainly solves the problems of high investment and complicated operation of adsorptive separation and purification of the para xylene. The method adopts a technical scheme that: the method comprises the following steps: delivering mixed xylene containing 60 to 95 percent of para xylene into a crystallizer for cooling crystallization, and crystallizing out slurry containing para xylene crystals; and delivering the slurry into a filtration and purification unit, and separating to obtain mother liquor, scourage and pure para xylene, wherein the filtration and purification unit is a tower washer. The method better solves the problems, and can be applied to industrial production.

Description

technical field [0001] The invention relates to a method for crystallizing and separating p-xylene. Background technique [0002] P-xylene is one of the main basic organic raw materials in the petrochemical industry. It is widely used in many chemical production fields such as chemical fibers, synthetic resins, pesticides, medicines, and plastics. The typical production method of p-xylene is from the thermodynamically balanced xylene containing ethylbenzene, that is, C8 aromatics generated by catalytic reforming of naphtha, through multi-stage cryogenic crystallization separation or molecular sieve simulated moving bed adsorption separation (adsorption separation for short) Technology to separate p-xylene from a mixture of isomers with similar boiling points. [0003] C 8 The boiling points of the components of aromatic hydrocarbons are close: ethylbenzene 136.2°C, p-xylene 138.4°C, m-xylene 139.1°C, ortho-xylene 144.4°C. Among them, o-xylene with the highest boiling point...

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): C07C15/08C07C7/14
Inventor 肖剑钟禄平卢咏琰郭艳姿
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