Method for extracting, distilling and recovering styrene from hydrocarbon mixture

A hydrocarbon mixture, extraction and rectification technology, applied in the direction of distillation purification/separation, organic chemistry, etc., can solve the problems that affect the long-term stable operation of the device, low polymer solubility, easy precipitation and blockage of equipment, etc., to achieve extended stability The effect of operating cycle, reducing the amount of polymerization inhibitor, and avoiding polymer precipitation

Active Publication Date: 2013-10-23
CHINA PETROLEUM & CHEM CORP +1
View PDF8 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0014] In the prior art, the solvent cannot take into account the contradiction between the selectivity of the key component o-xylene / styrene separation, the solubility of the polymer, and its own polymerization inhibition performance. Although sulfolane has good selectivity , but the solubility to polymer is low, once polymer is produced in the process, it is easy to precipitate and block the equipment
The existing polymerization inhibitors have a high boiling point, either the solubility is too low and easy to precipitate, or the dosage is large and the polymerization inhibition effect is not good, which affects the long-term stable operation of the entire device

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 extracting, distilling and recovering styrene from hydrocarbon mixture
  • Method for extracting, distilling and recovering styrene from hydrocarbon mixture
  • Method for extracting, distilling and recovering styrene from hydrocarbon mixture

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0035] pyrolysis gasoline C 8 The distillate is used as raw material, and its composition is listed in Table 1. according to figure 1 The shown flow process carries out extraction rectification to described raw material, reclaims styrene wherein, the composite solvent used contains the main solvent sulfolane of 99 mass %, the auxiliary solvent 4-methoxyphenol of 0.5 mass % and the water of 0.5 mass % . The polymerization inhibitor is 4-hydroxyl-2,2,6,6-tetramethylpiperidine nitroxide free radical (OH-TEMPO) of 55 mass %, 4,6-dinitro-2-secondary of 25 mass % Butylphenol (DNBP) and 20% by mass of N,N-diethylhydroxylamine. The mass ratio of the total amount of polymerization inhibitor to the raw material for extraction is 100 μg / g.

[0036] The number of theoretical plates of the extractive distillation column is 70, the top pressure of the column is 15kPa, the mass ratio of composite solvent / raw material is 3.8, and the reflux ratio is 2.0.

[0037] The number of theoretica...

example 2

[0040] By the method of example 1 from pyrolysis gasoline C 8 Styrene was recovered from the distillate, but the difference was that the co-solvent used was 3-methoxyphenol. Under the condition that the styrene purity was 99.7% by mass and the recovery rate was 95% by mass, the extractive distillation results are shown in Table 2.

example 3

[0042] By the method of example 1 from pyrolysis gasoline C 8 Styrene was recovered from the distillate, but the difference was that the cosolvent used was 2-methoxyphenol. Under the conditions of styrene purity of 99.7% by mass and recovery rate of 95% by mass, the results of extractive distillation are shown in Table 2.

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 extracting, distilling and recovering styrene from a hydrocarbon mixture. The method comprises the following steps of: extracting, distilling and recovering the styrene from the hydrocarbon mixture by using a composite solvent in the presence of a polymerization inhibitor. The composite solvent comprises 80-99% by mass of a main solvent, 0.01-19% by mass of an auxiliary solvent and 0.1-2.0% by mass of water, wherein the main solvent is a sulfone compound, and the auxiliary solvent is metoxyphenol or the mixture of the metoxyphenol and the glycol monomethyl ether. The polymerization inhibitor comprises 40-80% by mass of free radicals of nitrogen and oxygen, 15-50% by mass of nitro-phenol and derivatives thereof and 5-30% by mass of N, N-diethyl hydroxylamine. The use amount of the polymerization inhibitor is 10-500mug/g of the amount of the hydrocarbon raw material. Because the composite solvent is used together with the polymerization inhibitor, the use amount of the polymerization inhibitor can be decreased, and the rate of polymerization of the styrene can be reduced significantly.

Description

technical field [0001] The invention relates to a method for extracting and rectifying recovery of styrene from hydrocarbon mixtures, specifically, a method for extracting and rectifying recovery of styrene from hydrocarbon mixtures using a composite solvent. Background technique [0002] Styrene monomer is an important basic organic chemical raw material, and it is also widely used in coatings, pesticides, and medicine. According to statistics, the steam pyrolysis gasoline by-product of the ethylene cracking unit contains 3-5% styrene. Due to the difference in raw materials for a set of 1 million tons / year ethylene unit, the content of styrene in the pyrolysis gasoline is 20,000-30,000 tons / year . In the existing process of dealing with pyrolysis gasoline, this part of styrene is hydrogenated into ethylbenzene, which is stored in C 8 In the distillate, this ethylbenzene-rich C 8 The distillate is not ideal for supplying the downstream p-xylene unit as raw material. If u...

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): C07C15/46C07C7/08
Inventor 田龙胜唐文成赵明张云明边志凤高思亮
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