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

Pd catalyst supported by nitrogen-doped carbon material and preparation method thereof and application thereof in nitrobenzene catalytic hydrogenation reaction

A nitrogen-carbon material and catalyst technology, which is applied in the field of nitrogen-doped carbon material-supported Pd catalyst and its preparation, nitrobenzene catalytic hydrogenation reaction, can solve the problems of high reaction temperature, insufficient aniline selectivity, slow reaction, etc. Mild conditions, excellent catalytic activity, and simple operation

Active Publication Date: 2017-07-25
SOUTH CHINA UNIV OF TECH
View PDF6 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the process is simple, there are problems such as large amount of iron powder, serious environmental pollution, slow reaction and difficult product separation.
The advantages of phenol ammonolysis are simple process and cheap catalyst; but its disadvantages are high energy consumption, high production cost and large infrastructure investment
In the current industrialized production process, the reaction temperature is higher than 250°C, the hydrogen pressure is higher than 2MPa, and the selectivity of aniline is less than 99%.

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
  • Pd catalyst supported by nitrogen-doped carbon material and preparation method thereof and application thereof in nitrobenzene catalytic hydrogenation reaction
  • Pd catalyst supported by nitrogen-doped carbon material and preparation method thereof and application thereof in nitrobenzene catalytic hydrogenation reaction

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1~3

[0033] Add 20ml of absolute ethanol, 0.2ml of toluene (internal standard), 0.6g of nitrobenzene, and 4mg of catalysts loaded with Pd on different carriers into the autoclave in turn, stir and heat to 45°C, inject hydrogen, start timing, and During the reaction process, the pressure was maintained at 0.5 MPa. After 1.5 hours of reaction, the timing was stopped, the reactor was cooled to room temperature, and the liquid-solid phase mixture was filtered to obtain a solid catalyst and a liquid phase mixture containing unreacted reactants and reaction products. The liquid phase mixture was detected and analyzed by gas chromatography (GC).

Embodiment 1

[0034] The preparation process of the catalyst used in Example 1 is as follows: ultrasonically disperse 200 mg of carbon nanotubes in 20 ml of deionized water, then add 2.76 ml of 6.08 mg / ml palladium chloride solution, adjust the pH value to 8.5, and then add 10mg / mlNaBH 4 The solution was 5ml, stirred for 8h, filtered, washed, vacuum-dried, and ground to obtain a carbon nanotube-loaded Pd catalyst.

Embodiment 2

[0035] The catalyst used in embodiment 2 is to directly prepare nitrogen-doped carbon nanotubes by chemical vapor deposition and then prepare the catalyst. The specific preparation process is as follows: with 100mg FeMo / Al 2 o 3 As catalyst, 7.5ml xylene as carbon source, NH 3 (500ml / h) was used as nitrogen source, and nitrogen-doped carbon nanotubes were grown under the condition of raising the temperature to 800° C., reacted for 5 hours, and cooled to room temperature to obtain the product. Then the product was washed with concentrated hydrochloric acid (concentration: 35wt%) for 12 hours, filtered, dried and ground to obtain nitrogen-doped carbon nanotubes. Its specific surface area is 99m 2 / g, the X-ray photoelectron spectroscopy measurement shows that the nitrogen content is 4.21at%. Then ultrasonically disperse 200mg of nitrogen-doped carbon nanotubes in 20ml of deionized water, then add 2.76ml of 6.08mg / ml palladium chloride solution, adjust the pH value to 8.5, and...

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 Pd catalyst supported by a nitrogen-doped carbon material and a preparation method thereof and application thereof in nitrobenzene catalytic hydrogenation reaction. The method is as follows: first, placing a carbon material in an Ar atmosphere at 500-900 DEG C, injecting a nitrogen source for chemical vapor deposition reaction for 0.1-5h to obtain the nitrogen-doped carbon material; ultrasonically dispersing the nitrogen-doped carbon material in deionized water, adding a palladium chloride solution into the nitrogen-doped carbon material according to the mass ratio of Pd to nitrogen-doped carbon material of (1-100): 1000, adjusting pH value to 1 to 10, under the condition of ice bath, adding a NaBH4 solution, stirring, filtering, washing, drying under vacuum, and grinding to obtain the Pd catalyst supported by the nitrogen-doped carbon material. The Pd catalyst supported by the nitrogen-doped carbon material exhibits excellent catalytic activity when in use in the nitrobenzene hydrogenation. The Pd catalyst supported by the nitrogen-doped carbon material has the advantages of high product yield, simple preparation, easy recovery, simple operation and low cost, and the like.

Description

technical field [0001] The invention relates to the field of preparation of aniline, in particular to a nitrogen-doped carbon material loaded Pd catalyst and a preparation method thereof and its application in the catalytic hydrogenation reaction of nitrobenzene. Background technique [0002] Aniline is widely used in the production of polyurethane raw material diphenylmethane diisocyanate (MDI), medicine, rubber additives, fuel, pesticide and fine chemical intermediates, especially as a precursor of polyurethane, its market demand is increasing year by year, and it has great potential Market potential. [0003] At present, the production methods of aniline mainly include: (1) Fe powder reduction method, (2) phenol ammonia solution method, (3) nitrobenzene catalytic reduction method. The reduction method of iron powder is the earliest method for the commercial preparation of aniline. Although the process is simple, there are problems such as large amount of iron powder, se...

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
IPC IPC(8): B01J27/24B01J37/16C07C209/36C07C211/46
CPCB01J27/24B01J37/16C07C209/36C07C211/46
Inventor 余皓董宝强彭峰王红娟
Owner SOUTH CHINA UNIV OF TECH
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