Method for preparing norbornene in loop reactor

A loop reactor and norbornene technology, applied in the direction of addition of unsaturated hydrocarbons to hydrocarbons, etc., can solve problems such as harsh operating conditions, low ethylene reactivity, and difficult realization, and achieve fast heat transfer and high raw material selection The effect of improving sex and monomer conversion rate and safety factor

Inactive Publication Date: 2011-11-23
ZHEJIANG UNIV
View PDF8 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0024] In addition, some synthetic methods for synthesizing norbornene from dicyclopentadiene or cyclopentadiene are actually very difficult to realize industrially, because the reactivity of ethylene is low, and it requires harsh operating conditions

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 preparing norbornene in loop reactor
  • Method for preparing norbornene in loop reactor

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0048] The loop reactor used in this example has a length of 30 cm, an inner diameter of 2 cm, and a static mixer at the inlet. Dicyclopentadiene is partially or completely decomposed into cyclopentadiene by heating and pre-decomposing in a heat exchanger before entering the loop reactor, and the process conditions are 240°C and 5MPa. When ethylene enters the loop reactor, the temperature is 180°C and the absolute pressure is 5MPa. The pre-decomposition products of ethylene and dicyclopentadiene are respectively fed through metering pumps, and are fully mixed through static mixers when entering the loop reactor. Wherein, the feed flow rate of ethylene is 6.24mL / s, the feed flow rate of the pre-decomposition product of dicyclopentadiene is 1.41mL / s, the ethylene added to the loop reactor and the dicyclopentadiene before heating pre-decomposition The molar ratio of alkenes is 1. The temperature of the loop reactor is 180°C, the absolute pressure at the outlet is 5MPa; the mate...

Embodiment 2

[0050] The loop reactor used in this example has a length of 30 cm, an inner diameter of 2 cm, and a static mixer at the inlet. Dicyclopentadiene is partially or completely decomposed into cyclopentadiene by heating and pre-decomposing in a heat exchanger before entering the loop reactor, and the process conditions are 120°C and 8MPa. When ethylene enters the loop reactor, the temperature is 220°C and the absolute pressure is 10MPa. The pre-decomposition products of ethylene and dicyclopentadiene are respectively fed through metering pumps, and are fully mixed through static mixers when entering the loop reactor. Wherein, the feed flow rate of ethylene is 4.64mL / s, the feed flow rate of the pre-decomposition product of dicyclopentadiene is 0.75mL / s, the ethylene added to the loop reactor and the dicyclopentadiene before heating pre-decomposition The molar ratio of alkenes is 2. The temperature of the loop reactor is 220°C, the absolute pressure at the outlet is 10MPa; the ma...

Embodiment 3

[0052] The loop reactor used in this example has a length of 30 cm, an inner diameter of 2 cm, and a static mixer at the inlet. Dicyclopentadiene is partially or completely decomposed into cyclopentadiene by heating and pre-decomposing in a heat exchanger before entering the loop reactor, and the process conditions are 150°C and 13MPa. The temperature of ethylene entering the loop reactor is 260°C and the absolute pressure is 15MPa. The pre-decomposition products of ethylene and dicyclopentadiene are respectively fed through metering pumps, and are fully mixed through static mixers when entering the loop reactor. Wherein, the feed flow rate of ethylene is 3.27mL / s, the feed flow rate of the pre-decomposition product of dicyclopentadiene is 0.11mL / s, the ethylene added to the loop reactor and the dicyclopentadiene before heating pre-decomposition The molar ratio of alkenes is 16. The temperature of the loop reactor is 260° C., and the absolute pressure at the outlet is 15 MPa...

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 method for preparing norbornene in a loop reactor. The method disclosed by the invention comprises the following steps of: (1) heating and pre-decomposing dicyclopentadiene in a heat exchanger to partially or wholly decompose the dicyclopentadiene into cyclopentadiene, wherein the temperature for heating and pre-decomposing is in a range of 120-240 DEG C and the absolute pressure is in a range of 5-30 MPa; (2) transporting the heated and pre-decomposed product of the step (1) into the loop reactor through the heat exchanger, adding ethylene into the loop reactor at the same time and reacting to obtain the norbornene, wherein the reaction conditions are as follows: the temperature is in a range of 180-300 DEG C, the absolute pressure of an outlet of the loop reactor is in a range of 5-30 MPa, the mol ratio of the ethylene to the dicyclopentadiene which is not heated and pre-decomposed is 1-20 to 1, the recycle ratio is 100-300 to 1, and the temperature and the pressure of the ethylene in the process of adding the ethylene into the loop reactor are the same as those in the reaction conditions. According to the method provided by the invention, the safety of the preparation process can be remarkably improved and higher selectivity and conversion rate of the cyclopentadiene can be realized.

Description

technical field [0001] The present invention relates to a process for the production of norbornene by reacting ethylene with cyclopentadiene (CPD), or ethylene with a mixture of dicyclopentadiene (DCPD) and cyclopentadiene (CPD). Background technique [0002] The synthesis of norbornene was first described by L. M. Joshel and L. W. Butz in 1941. The reaction of synthesizing norbornene is Diels-Alder reaction, cyclopentadiene The two double bonds are broken, the 2-position and 3-position form a double bond, and the 1-position and 4-position condense with ethylene to generate norbornene: [0003] [0004] The reaction of ethylene with cyclopentadiene is strongly exothermic, ΔH° 298 =-22kcal / mol ideal gas. Cyclopentadiene is a more sensitive product to these explosive reactions than ethylene. M. Ahmed of Union Carbide Corporation proposed that cyclopentadiene can continuously undergo exothermic reaction at the following temperature after being heated under pressure: ...

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): C07C13/42C07C2/50
Inventor 姚臻曹堃戴斌斌张岩
Owner ZHEJIANG UNIV
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