Macroporous alumina and preparation method thereof

A technology of macroporous alumina and pore diameter, applied in the field of macroporous alumina and its preparation, can solve the problems of reduced mechanical strength, apparent isolation, and poor spatial continuity, and achieve stress relief, increase specific surface area, and high crushing strength Effect

Active Publication Date: 2019-11-19
CHINA PETROLEUM & CHEM CORP +1
View PDF17 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method is based on the content of polyethylene glycol to control the formation and pore size of macropores. Although macropores of 50nm-10000nm can be obtained, it has the following disadvantages: (1) It is easier to generate macropores larger than 1 μm, However, it is difficult to control the macropores smaller than 1 μm, and the macropores obtained in the actual preparation of the examples are all macropores above 1 μm; (2) The obtained macropores are apparently isolated and have poor spatial continuity, which is not conducive to the transmission of macromolecules. (3) The obtained material forms amorphous macroporous alumina at a lower calcination temperature (550-650°C), and this amorphous alumina material is not conducive to catalytic applications
If the macropore diameter in the catalyst is too large and the content is too large, the overall porosity of the carrier material will decrease, and the mechanical strength will also seriously decrease

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
  • Macroporous alumina and preparation method thereof
  • Macroporous alumina and preparation method thereof
  • Macroporous alumina and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] Preparation of aluminum sol: Boehmite powder and distilled water are mixed to form a suspension (solid content 3wt%). Under continuous stirring, hydrochloric acid is added dropwise to meet the acid / aluminum molar ratio of 0.07. hours to form a clear aluminum sol.

[0040] At room temperature (about 25°C), mix water, absolute ethanol, aluminum chloride, polyethylene glycol, aluminum sol, and formamide evenly, and then add pyridine. The contents of each component of the mixture are by weight: water 22% , ethanol 21%, aluminum chloride 18%, polyethylene glycol (viscosity average molecular weight 1 million) 0.3%, aluminum sol 5%, formamide 1%, pyridine 32.7%. After mixing evenly, the obtained gel was aged at 40°C for 48 hours, and then soaked in 55wt% ethanol aqueous solution for 48 hours. After soaking and removing the liquid phase, it was dried at 40°C until the product no longer showed obvious weight loss. Then calcined at 550° C. for 3 hours, and then cooled to room t...

Embodiment 2

[0042] The preparation of aluminum sol is the same as in Example 1.

[0043] At room temperature (about 25°C), mix water, absolute ethanol, aluminum chloride, polyethylene glycol, aluminum sol, and acetamide evenly, and then add propylene oxide. The contents of each component of the mixture are by weight: water 23%, ethanol 20%, aluminum chloride 22%, polyethylene glycol (viscosity average molecular weight 1 million) 0.5%, aluminum sol 2%, formamide 2.0%, propylene oxide 30.5%. After mixing evenly, the obtained gel was aged at 40°C for 48 hours, and then the aged mixture was soaked in ethanol for 48 hours. After soaking and removing the liquid phase, it was dried at 40°C until the product no longer lost weight. Then bake at 450° C. for 5 hours, and then cool to room temperature to obtain the macroporous alumina. According to the XRD test, it has a good γ crystal state, the total porosity is 84%, the macropores are evenly distributed, and it has a three-dimensional space. The ...

Embodiment 3

[0045] Preparation of aluminum sol: Boehmite powder and distilled water are mixed to form a suspension (solid content 1.5wt%). Under continuous stirring, acetic acid is added dropwise to meet the acid / aluminum molar ratio of 0.1. After the addition, the temperature is raised to 90°C and refluxed A clear sol formed in 10 hours.

[0046] At room temperature (about 25°C), mix water, absolute ethanol, aluminum chloride, polyethylene glycol, aluminum sol, and N,N-dimethylformamide evenly, and then add pyridine. The components of the mixture are calculated by weight. The contents are: water 20%, ethanol 20%, aluminum chloride 22%, polyethylene glycol (viscosity average molecular weight 1 million) 0.5%, aluminum sol 5%, formamide 2.5%, pyridine 30.0%. After mixing evenly, the obtained gel was aged at 40°C for 48 hours, and then soaked in 80wt% ethanol aqueous solution for 72 hours. After soaking and removing the liquid phase, it was dried at 40°C until the product no longer had obvio...

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

PropertyMeasurementUnit
pore sizeaaaaaaaaaa
specific surface areaaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses macroporous alumina and a preparation method thereof. The macroporous alumina of the invention has the properties that the macroporous alumina is a gamma crystalline state, thetotal porosity is 60%-85%, the macropore diameter is 100 nm-1000 nm, the proportion of macropores to the total porosity is 40%-75%, the macropores are evenly distributed and three-dimensionally penetrated, a ratio of the wall thickness to the pore diameter of the macropores is 0.7-3.0, and the side crushing strength is 8-25 N/mm. The preparation method of the macroporous alumina includes the following steps: (1) preparing aluminum sol; (2) evenly mixing inorganic aluminum salts, polyethylene glycol, the aluminum sol obtained in the step (1), organic compounds containing amide groups and a low-carbon alcohol aqueous solution; (3) adding epoxypropane and/or pyridine into the mixture obtained in the step (2), evenly mixing the mixture to obtain gel, and carrying out aging to obtain an agingproduct; and (4) immersing the aging product by using the low-carbon alcohol aqueous solution, carrying out solid-liquid separation, and drying and roasting a solid phase to obtain the macroporous alumina.

Description

technical field [0001] The invention relates to a macroporous alumina and a preparation method thereof, belonging to the field of inorganic material preparation. Background technique [0002] Activated alumina As a good hydrogenation catalyst support material, alumina has been widely used in the oil refining industry. In practical industrial catalytic applications, in addition to reactive pores of appropriate size (5 nm -20 nm), some large pores (above 100 nm) are required as efficient macromolecular mass transfer channels in the catalyst. [0003] Acta Physicochemical Sinica, 2005, 21 (02): 221-224., using aluminum nitrate as a precursor, ethanol as a solvent, formamide as a drying control chemical additive, and propylene oxide as a gel network inducer, through sol-gel Alumina gels were prepared by this method, and light, massive alumina aerogels with concentrated mesoporous distribution were obtained under normal pressure and drying conditions. However, this airgel mater...

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): C01F7/02B01J21/04B01J35/10B01J32/00
CPCB01J21/04B01J35/1019B01J35/1042B01J35/1047B01J35/1066B01J35/1071C01F7/02C01P2006/12C01P2006/14C01P2006/17C01P2006/21
Inventor 杨卫亚凌凤香张会成王少军沈智奇
Owner CHINA PETROLEUM & CHEM CORP
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