3-cyanopyridine absorption method

The technology of a cyanopyridine and an absorption tower is applied in the absorption field of 3-cyanopyridine, which can solve the problems such as easy hydrolysis of 3-cyanopyridine, and achieve the effects of reducing energy consumption, improving absorption efficiency and achieving good technical effect.

Active Publication Date: 2007-10-03
SHANGHAI RES INST OF PETROCHEMICAL TECH SINOPEC
View PDF4 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0010] The technical problem to be solved by the present invention is that when using circulating aqueous solution to absorb 3-cyanopyridine in the past literature, the theoretical plate number of the absorption tower, the circulation ratio and the problem that 3-cyanopyridine is easily hydrolyzed in the tower kettle are not involved, and provide A New Absorption Method of 3-cyanopyridine

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
  • 3-cyanopyridine absorption method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023]The gas-phase reaction product of 3-cyanopyridine obtained by the ammoxidation of 3-picoline is subjected to cyclic absorption in two towers, and the schematic diagram of the process flow is shown in Figure 1. The flow rate of the gaseous reaction product entering the first absorption tower is 1764.08 kg / hour, the temperature is 390°C, and the pressure is 40KPa, wherein the flow rate of 3-cyanopyridine is 152.76 kg / hour. The number of theoretical plates of the first absorption tower is 6, the pressure at the top of the tower is 30KPa, the pressure at the bottom of the tower is 35KPa, the temperature at the top of the tower is 46°C, the temperature at the bottom of the tower is 60°C, the weight ratio of liquid to gas is 10, and the temperature of the liquid circulating to the top of the tower is 45°C. The number of theoretical plates of the second absorption tower is also 6, the pressure at the top of the tower is 20KPa, the pressure at the bottom of the tower is 25KPa, th...

Embodiment 2

[0025] The absorption process conditions are the same as in Example 1, except that the concentration of 3-cyanopyridine in the bottom liquid of the first absorption tower remains 4% by weight, and the yield of 3-cyanopyridine is 96.6% by weight.

Embodiment 3

[0027] The absorption process conditions are the same as in Example 1, except that the number of theoretical plates in the first absorption tower and the second absorption tower is 12, and the yield of 3-cyanopyridine is 96.2% by weight.

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

This invention relates to a absorption approach of 3 - cyan pyridine, mainly solve the problem that while using circulating water solution to assimilate 3 - cyan pyridine in anciently literature, not involved with theoretical plate number of absorption column, weight proportion of liquid and air, as well as 3 - cyan pyridine easily hydrolyzing. This invention adopts two tandem circulation absorption columns. Control the concentration of 3 - cyan pyridine in first absorption column bottom at 3 to 10 percent of weight, the liquid temperature while circulating to overhead is 5 to 50 deg, theoretical plate number of absorption column is 2 to 20 pieces, weight proportion of liquid and air is 2 to 15. The weight ratio between liquid circulating to second absorption column overhead and circulating to first absorption column overhead is 0.25 to 0.8.

Description

technical field [0001] The invention relates to a method for absorbing 3-cyanopyridine. Background technique [0002] 3-cyanopyridine (3-cyanopyridine), also known as nicotinic acid nitrile (nicotinonitrile), is an important chemical raw material. It is an intermediate for the preparation of niacin and niacinamide. Niacin and niacinamide belong to the B vitamins and are widely used in medicine, food and feed additive industries. [0003] There are many ways to synthesize 3-cyanopyridine, among which 3-picoline ammoxidation is one of the most important methods. At present, the level of catalyst used in this method is relatively high, and there are related patent documents at home and abroad, but there are not many reports on the subsequent absorption process involving 3-cyanopyridine. [0004] US Patent No. 2,861,999 proposes a method for obtaining cyanopyridine. After the reaction product passes through a cooling condenser, a dry ice trap ...

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): C07D213/85
Inventor 沈伟胡力智陈金华
Owner SHANGHAI RES INST OF PETROCHEMICAL TECH SINOPEC
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