Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for preparing olefins via light alkane dehydrogenation

A technology for producing low-carbon alkanes and olefins, which is applied in the field of dehydrogenation of C3~C4 alkanes to olefins. It can solve the problems of difficult utilization of hydrogen, reduce the processing capacity of the reactor, and increase the cost of raw materials, so as to improve selectivity, reduce side reactions, The effect of high purity hydrogen

Active Publication Date: 2013-02-06
CHINA PETROLEUM & CHEM CORP +1
View PDF8 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In the relevant documents and patents of the dehydrogenation process of low-carbon alkanes, hydrogen, nitrogen or other inert gases are also used as diluents in the feed to improve the conversion rate of alkanes and the selectivity of olefins, but the addition of nitrogen in the feed will increase The cost of raw materials, and the hydrogen generated by dehydrogenation is not easy to use; and adding a large amount of nitrogen will reduce the processing capacity of the reactor

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

[0019] An isobutane dehydrogenation catalyst is composed of Pt 0.4wt%, Sn 0.8wt%, K 0.7wt%, and 6 ml of the above catalyst is packed in a tubular reactor with an inner diameter of 11 mm. After the catalyst is reduced with hydrogen at 500°C, the temperature is raised and isobutane gas is passed through to carry out the reaction of dehydrogenation to isobutene. At a temperature of 550°C, the space velocity of isobutane is 2 h -1 , reaction under normal pressure, the conversion rate of isobutane is 36.2%, the selectivity of isobutene is 93% (based on the number of moles of isobutane converted, the same below), the main by-products are methane, propane, propylene and The isomer of isobutene has a selectivity of about 7%.

[0020] During the reaction, 100~10000μg / g ethylenediamine was added through an additional pipeline, and the reaction conditions remained unchanged. The results are shown in the following table. The results of adding different amounts of ethylenediamine dehydrog...

Embodiment 2

[0023] An isobutane dehydrogenation catalyst is composed of Pt 0.7wt%, Sn 1.0wt%, K 1.0wt%, and 6 ml of the above catalyst is packed in a tubular reactor with an inner diameter of 11 mm. After the catalyst is reduced with hydrogen at 500°C, the temperature is raised and isobutane gas is passed through to carry out the reaction of dehydrogenation to isobutene. At a temperature of 580°C, the space velocity of isobutane is 3 h -1 , Reaction under normal pressure, the conversion rate of isobutane is 38.2%, the selectivity of isobutene is 92%, the main by-products are isomers of methane, propane, propylene and isobutene, and its selectivity is about 8%.

[0024] Adding 400μg / g methylamine to the raw material, under the same conditions, the conversion rate of isobutane remains unchanged, and the selectivity of isobutene is increased to 93.6%.

Embodiment 3

[0026] An isobutane dehydrogenation catalyst is composed of Pt 0.5wt%, Sn 0.3wt%, K 0.5wt%, and 6 ml of the above catalyst is packed in a tubular reactor with an inner diameter of 11 mm. After the catalyst is reduced with hydrogen at 500°C, the temperature is raised and isobutane gas is passed through to carry out the reaction of dehydrogenation to isobutene. At a temperature of 540°C, the volume space velocity of isobutane is 2 h -1 , Reaction under normal pressure, the conversion rate of isobutane is 37.2%, the selectivity of isobutene is 92%, the main by-products are isomers of methane, propane, propylene and isobutene, and its selectivity is about 9%.

[0027] In the reaction, 300 μg / g of pyridine was added through an additional pipeline, dehydrogenation under the same conditions, the conversion rate of isobutane remained unchanged, and the selectivity of generating isobutene rose to 94.4%; after adding 300 μg / g of pyridine for 25 hours, Change into pure isobutane raw mate...

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 present invention discloses a method for preparing olefins via light alkane dehydrogenation. Under dehydrogenation process conditions of light alkanes, light alkanes raw materials in a gas phase contact with a solid catalyst for dehydrogenation reaction; and simultaneously nitrogen-containing organic compounds are added into the reactor continuously or intermittently, wherein the added nitrogen-containing organic compounds have a carbon atom number of 1 to 18, and the adding amount of the nitrogen-containing organic compounds enables the content of the nitrogen-containing organic compounds to be from 10 to 10000 [mu]g / g in the light alkanes. According to the method of the present invention, the reaction process is controlled to raise selectivity of desired products, and the method is simple to realize, high in purity of obtained hydrogen gas, and suitable for industrial applications.

Description

technical field [0001] The invention relates to a preparation method for dehydrogenating low-carbon alkanes to olefins, in particular to a process method for dehydrogenating C3-C4 alkanes to produce olefins. Background technique [0002] The catalytic dehydrogenation reaction of low-carbon alkanes is limited by thermodynamic equilibrium and needs to be carried out under harsh conditions of high temperature and low pressure. Excessively high reaction temperature will intensify the cracking reaction and deep dehydrogenation of low-carbon alkanes, and the selectivity will decrease; at the same time, it will accelerate the carbon deposition on the surface of the catalyst and cause the catalyst to deactivate rapidly. Due to the low alkane conversion rate and shortened catalyst life under severe reaction conditions, the industrial application of the dehydrogenation of light alkanes to olefins is limited. Therefore, the development of catalysts with high selectivity and high stabi...

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): C07C5/333C07C11/02C07C11/09
Inventor 张海娟李江红张喜文宋喜军孙潇磊王振宇
Owner CHINA PETROLEUM & CHEM CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com