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

A method for preparing pyromellitic dianhydride based on graphene sponge catalysis

A technology of pyromellitic dianhydride and graphene sponge is applied in catalyst activation/preparation, chemical instruments and methods, physical/chemical process catalysts, etc., and can solve the problems of low content of catalyst active components and limited improvement of catalytic efficiency.

Active Publication Date: 2020-10-23
连云港鹏辰特种新材料有限公司
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] It can be seen from the above prior art that the existing catalysts of pyromellitic dianhydride prepared based on the oxidation of durene as a raw material mostly use the active material to be attached to the surface of the inert carrier by spraying to improve the mechanical properties of the catalyst. The content of active components in the catalyst prepared by this method is small, and the improvement of catalytic efficiency is limited. Therefore, the preparation of a catalyst with excellent mechanical properties and heat dissipation performance in the preparation of pyromellitic dianhydride is expected to significantly increase the production of pyromellitic dianhydride. rate and purity

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

[0028] (1) Add oxalic acid to deionized water, heat until completely dissolved, add ammonium metavanadate to mix, continue to stir, add dropwise H 2 PdCl 4 After the solution is fully mixed, a microemulsion is formed after removing air bubbles, wherein the mass ratio of vanadium and palladium in the microemulsion is 0.3:1, and the solid content is 15%.

[0029] (2) Add the microemulsion into the graphene oxide solution, stir at high speed until the mixture is uniform, and obtain a precursor solution with a graphene oxide content of 0.5wt%, and place the precursor solution in liquid nitrogen for 5 seconds for quick freezing, and then in vacuum drying at -20°C for 24 hours to obtain a graphene oxide-based porous sponge.

[0030] (3) The graphene oxide-based porous sponge is reduced by double-beam laser radiation with wavelengths of 355nm and 532nm, and the energy range is 20J / cm 2 , the time of processing is 5min, obtains graphene-based vanadium-palladium porous sponge catalys...

Embodiment 2

[0033] (1) Add oxalic acid to deionized water, heat until completely dissolved, add ammonium metavanadate to mix, continue to stir, add dropwise H 2 PdCl 4 After the solution is fully mixed, a microemulsion is formed after removing air bubbles, wherein the mass ratio of vanadium and palladium in the microemulsion is 1.5:1, and the solid content is 35%.

[0034] (2) Add the microemulsion to the graphene oxide solution, stir at high speed until the mixture is uniform, and obtain a precursor solution with a graphene oxide content of 15wt%, and place the precursor solution in liquid nitrogen for 10 seconds for quick freezing, and then in - Vacuum drying at 20°C for 48 hours to obtain a graphene oxide-based porous sponge.

[0035] (3) The graphene oxide-based porous sponge is reduced by double-beam laser radiation with wavelengths of 355nm and 532nm, and the energy range is 50J / cm 2 , the processing time is 30min, and the graphene-based vanadium-palladium porous sponge catalyst is ...

Embodiment 3

[0038] (1) Add oxalic acid to deionized water, heat until completely dissolved, add ammonium metavanadate to mix, continue to stir, add dropwise H 2 PdCl 4 After the solution is fully mixed, a microemulsion is formed after removing air bubbles, wherein the mass ratio of vanadium and palladium in the microemulsion is 0.8:1, and the solid content is 20%.

[0039] (2) Add the microemulsion to the graphene oxide solution, stir at a high speed until the mixture is uniform, and obtain a precursor solution with a graphene oxide content of 5wt%, place the precursor solution in liquid nitrogen for 7 seconds for quick freezing, and then - Vacuum drying at 20°C for 36 hours to obtain a graphene oxide-based porous sponge.

[0040] (3) The graphene oxide-based porous sponge is reduced by double-beam laser radiation with wavelengths of 355nm and 532nm, and the energy range is 35J / cm 2 , the time of processing is 15min, obtains graphene base vanadium palladium porous sponge catalyst.

[0...

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 pyromellitic dianhydride based on graphene sponge catalysis, which includes the following steps: adding oxalic acid to deionized water to dissolve, adding ammonium metavanadate to mix, continuing to stir, and dropwise adding palladium chloride solution Form a microemulsion; add the microemulsion to the graphene oxide solution, stir evenly at high speed to obtain a precursor solution, place the precursor solution in a low temperature environment for rapid freezing and vacuum drying, and then undergo laser radiation reduction treatment to obtain graphene Graphene-based vanadium-palladium porous sponge catalyst; Place the graphene-based vanadium-palladium porous sponge catalyst in a fixed bed of gas phase oxidation reaction. After heating the fixed bed, introduce a mixture of pyrotetramethylbenzene and air, and use molten salt circulation for heat exchange and cooling reaction. Collect, hydrolyze and crystallize and sublimate to obtain pyromellitic dianhydride. The invention applies a catalyst with high catalytic activity and good thermal stability to the preparation of pyromellitic dianhydride, and the preparation product has high efficiency and good purity.

Description

technical field [0001] The invention belongs to the technical field of pyromellitic dianhydride preparation, and in particular relates to a method for preparing pyromellitic dianhydride based on graphene sponge catalysis. Background technique [0002] Pyromellitic dianhydride is a very important chemical raw material, mainly used as monomer of polyimide, polyimidazole and other heat-resistant resins, powder coating matting agent intermediate, pharmaceutical intermediate, epoxy resin curing agent, etc. , is a fine chemical product with a wide range of uses. [0003] At present, the preparation of pyromellitic dianhydride mainly includes durene oxidation method, trimethylene alkylation method and carbon monoxide method. The gas-phase oxidation method only needs one-step air catalytic oxidation, the preparation method is simple, it can be produced continuously, and it is easy to automate management. However, the pyromellitic dianhydride prepared by the gas-phase oxidation meth...

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 Patents(China)
IPC IPC(8): C07D493/04B01J23/648B01J35/04B01J37/34B01J37/00
CPCC07D493/04B01J23/6482B01J37/0018B01J37/341B01J37/343B01J35/56
Inventor 谈勇谈俊江晓龙
Owner 连云港鹏辰特种新材料有限公司
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