Process for preparing n-hexylic acid by oxidation of sec- octyl alcohol with nitric acid and its special device

A nitric acid oxidation and sec-octanol technology, which is applied in the oxidation preparation of carboxylic acid, organic chemistry, etc., can solve the problems of waste of resources, complicated operation, uneven gas-liquid mixing, etc., to reduce NO content, reduce air pollution, and reduce workload small effect

Inactive Publication Date: 2005-11-23
HENAN UNIVERSITY
View PDF3 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The disadvantages are: the incoming air cannot be fully mixed with the oxidizing solution and NO, which affects the ventilation effect; a large amount of thin acidic wastewater containing acetic acid, nitric acid, etc. is produced during washing, polluting the environment and wasting resources
CN1031702C adopts the method of vacuuming under stirring, and automatically enters oxygen during the oxidation process, which overcomes the shortcoming that the air flow rate in CN1035106A should not be too large, otherwise it is easy to leak, but it still does not solve the problem of uneven gas-liquid mixing in ventilation
Recovering acetic acid by this method consumes a large amount of alkali and energy, and the operation is too complicated, and the economic feasibility is poor

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
  • Process for preparing n-hexylic acid by oxidation of sec- octyl alcohol with nitric acid and its special device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0014] 1600Kg secondary octanol (weight content≤82%) and 2.0Kg V 2 o 5 It is fed into the reactor through the feeding port on the upper part of the jet-down reactor reactor 1. Start the non-leakage pump 13 to mix and circulate the materials and heat them. When the temperature > 95°C, open the nitric acid feed pipe 12 and the air inlet 11, nitric acid, air, 2-octanol, catalyzer and the nitric oxide emitted in the reaction sucked through the liquid jet vacuum pump suction port 9 via the reaction mixture outlet 5 Gases and the like are uniformly mixed in the jet vacuum pump 6. Control nitric acid addition speed, make reaction temperature2 )2.1312mg / m 3 . After the addition of nitric acid, the temperature was raised to 120°C, and the temperature was kept at full reflux for 3 hours to complete the oxidation. After the heat preservation is over, the natural cooling is allowed to stand for stratification, and the acid-containing water layer (recycled for diluting nitric acid) is...

Embodiment 2

[0016] Embodiment 2, in the present embodiment, add the secondary octanol 1500Kg after absorbing nitric oxide, the front and rear cuts in the rectification are 100Kg altogether, V 2 o 5 2.0Kg, and dilute to the nitric acid 3850Kg of weight percentage concentration 45% with separating spent acid, equipment used and concrete operation are with embodiment 1. After purification, 1880Kg of oxidation solution is obtained, the weight content of hexanoic acid is ≥63%, the weight content of acetic acid is ≥27%, and the content of nitrogen oxides in the exhaust tail gas (converted into NO 2 )≤3.5mg / m 3 .

Embodiment 3

[0017] Embodiment 3, in the present embodiment, add the secondary octanol 1500Kg after absorbing nitric oxide, the front and rear cuts in the rectification are 100Kg altogether, V 2 o 5 2.0Kg, and 3850Kg of nitric acid diluted to weight percentage concentration 45% with separating waste acid, used equipment and concrete operation are as embodiment 1. After purification, 1883Kg of oxidation solution is obtained, the weight content of hexanoic acid is ≥63%, the weight content of acetic acid is ≥29%, and the content of nitrogen oxides in the exhaust tail gas (converted into NO 2 )≤3.5mg / m 3 .

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 disclosed method includes a capryl alcohol oxidation step and a crude oxidation liquid purification step, wherein in the capryl alcohol oxidation step, a downward injection type reactor is employed to use the closed injection cycle of the reaction liquid for charging nitric acid, air and nitroxides gases produced in the reaction into the reactor for mixing and reacting with capryl alcohol, in the crude oxidation liquid purification step, a non-washing physical method, i.e. an air blowing method is employed to remove the inorganic acidic impurity in the oxidation liquid, the processing time being 0.5-2.0 hours.

Description

technical field [0001] The invention belongs to the technical field of n-hexanoic acid preparation, in particular to a method for producing n-hexanoic acid by oxidizing sec-octanol with nitric acid and its special equipment—a downward jet reactor. Background technique [0002] N-hexanoic acid is a colorless or light yellow transparent liquid, almost insoluble in water, easily soluble in ethanol and ether. It can be used as the raw material of spices such as ethyl caproate, propylene caproate, glyceryl tricaproate, the raw material of long-acting contraceptive norethindrone caproate and ringworm medicine, and it can also be used as a thickener for lubricants. N-hexanoic acid is generally prepared by oxidizing sec-octanol with nitric acid, and the reaction formula for preparing n-hexanoic acid by oxidizing sec-octanol with nitric acid is: <chemistry num="001"> <chem file="200410010266_cml001.xml" / > < / chemistry> , the reaction is carried out in the presenc...

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): C07C53/126
Inventor 高飞务宗伟
Owner HENAN UNIVERSITY
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