Method for preparing benzaldehyde through phenylcarbinol oxidation

A technology of benzaldehyde and benzyl alcohol, applied in the field of preparation of benzaldehyde, can solve the problem of low selectivity

Inactive Publication Date: 2012-10-10
BEIJING UNIV OF CHEM TECH
View PDF4 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The purpose of the invention is to solve the problem of low selectivity caused by peroxidation in the preparation of benzaldehyde from benzyl alcohol, by utilizing constant voltage electrolysis, in supercritical CO 2 Effectively improve the selectivity of benzyl alcohol oxidation to benzaldehyde in the system, and reduce environmental pollution

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

[0029] This embodiment illustrates that benzyl alcohol is dissolved in ionic liquid [Bmim][PF 6 ] of supercritical CO 2 2.7 V constant voltage electrolysis in the medium, the reaction temperature is 45 ℃, the current flow is 99 ℃, the method of oxidation to produce benzaldehyde.

[0030] Take 0.05 g of benzyl alcohol and ionic liquid [Bmim][PF 6 ] 2.00 g, acetonitrile 12.00 g, put into a 50mL three-electrode autoclave, and seal. Then use CO 2 The sampler fills the reactor with CO 2 When the pressure is 0.3 ~ 0.4 MPa, then open the gas outlet to reduce the gas pressure to 0.1 MPa, repeat this 3 ~ 4 times, and drain the air in the reactor. Continue to pass CO into the reactor 2 , the incoming CO 2 The mass is about 31.5 g, and then the reaction kettle is placed in a water bath with a temperature of 45 °C, and the stirring is turned on. After a period of time, when the reaction pressure was stabilized at 15.6 MPa, connect the three electrodes of the electrochemical worksta...

Embodiment 2

[0033] This embodiment illustrates that benzyl alcohol is dissolved in ionic liquid [Bmim][PF 6 ] of supercritical CO 2 2.7 V constant voltage electrolysis in the medium, the reaction temperature is 45 ℃, the current flow is 89 ℃, the method of oxidation to produce benzaldehyde.

[0034] Take 0.05 g of benzyl alcohol and ionic liquid [Bmim][PF 6 ] 2.00 g, acetonitrile 12.00 g, put into a 50mL three-electrode autoclave, and seal. Then use CO 2 The sampler fills the reactor with CO 2 When the pressure is 0.3 ~ 0.4 MPa, then open the gas outlet to reduce the gas pressure to 0.1 MPa, repeat this 3 ~ 4 times, and drain the air in the reactor. Continue to pass CO into the reactor 2 , the incoming CO 2The mass is about 31.6 g, and then the reaction kettle is placed in a water bath with a temperature of 45 °C, and the stirring is turned on. After a period of time, when the reaction pressure was stabilized at 16.48MPa, connect the three electrodes of the electrochemical workstat...

Embodiment 3

[0037] This embodiment illustrates that benzyl alcohol is dissolved in ionic liquid [Bmim][PF 6 ] of supercritical CO 2 2.7 V constant voltage electrolysis in the medium, the reaction temperature is 45 ℃, the current flow is 109 C, the process method of oxidation to produce benzaldehyde.

[0038] Take 0.05 g of benzyl alcohol and ionic liquid [Bmim][PF 6 ] 2.00 g, acetonitrile 12.00 g, put into three-electrode autoclave, seal. Then use CO 2 The sampler fills the reactor with CO 2 When the pressure is 0.3 ~ 0.4 MPa, then open the gas outlet to reduce the gas pressure to 0.1 MPa, repeat this 3 ~ 4 times, and drain the air in the reactor. Continue to pass CO into the reactor 2 , the incoming CO 2 The mass is about 31.6 g, and then the reaction kettle is placed in a water bath with a temperature of 45 °C, and the stirring is turned on. After a period of time, when the reaction pressure was stabilized at 16.48MPa, connect the three electrodes of the electrochemical workstati...

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 provides a method for preparing benzaldehyde through phenylcarbinol oxidation. According to the method, ionic liquid serves as a supporting electrolyte, acetonitrile serves as a cosolvent, a high-pressure reactor provided with electrodes is used for performing electrochemical electrolysis in a supercritical CO2 environment with a reaction temperature of 25-70 DEG C (system pressure is 10-25MPa), and the phenylcarbinol is converted to the benzaldehyde through selective oxidation. According to the method, features of the supercritical CO2 such as small viscosity, zero surface tension and friendly environment are utilized, advantages of the ionic liquid such as stable physicochemical properties and high electrical conductivity are combined, a constant potential electrolysis technology is adopted to control the efficient selective oxidation of the phenylcarbinol to the benzaldehyde effectively, and the yield and the selectivity of the benzaldehyde can reach above 99.8% under an optimum condition.

Description

technical field [0001] The invention relates to a method for preparing benzaldehyde. Specifically, the present invention relates to a method for the electrochemical oxidation of benzyl alcohol to benzaldehyde. Background technique [0002] Aromatic aldehydes are an important class of organic chemical intermediates, mainly used in medicine, plastics, additives, spices and other industries. Therefore, the oxidation of aromatic alcohols to corresponding aromatic aldehydes is a very important organic reaction. However, because aromatic aldehydes are prone to peroxidation to generate carboxylic acids, the selectivity of aromatic alcohols to aromatic aldehydes is greatly reduced, which severely restricts the yield of aromatic aldehydes. In recent years, many researchers have used transition metal catalysts to improve the selectivity of benzyl alcohol oxidation to benzaldehyde, and achieved good results, but they are still subject to various constraints, such as: catalysts and org...

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): C25B3/02C25B3/23
CPCY02P20/54
Inventor 吴卫泽孙楠楠
Owner BEIJING UNIV OF CHEM TECH
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