Preparation process for large pore volume and light bulk density activated alumina

A preparation process, alumina technology, applied in the direction of alumina/aluminum hydroxide, etc., can solve the problems of large differences in the performance of alumina carriers, large ratio of micropores to mesopores, unreasonable pore distribution, etc., to save washing water , low cost, optimized hole distribution effect

Inactive Publication Date: 2012-10-17
JIANGSU JINGJING NEW MATERIALS
View PDF7 Cites 45 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, large pore volume and low density γ-Al are prepared at home and abroad 2 o 3 Among the routes, foreign countries mainly use aluminum alcohol hydrolysis, which has less environmental pollution, low impurity content, and good physical and chemical properties, but the production cost is relatively high; domestically, AlCl 3 -NH 4 Preparation of γ-Al by OH Method 2 o 3 , the product has high purity, low specific surface area and moderate pore distribution
CN87101513A Bimodal γ-Al prepared by neutralizing, aging, filtering, washing, acidifying, drying, roasting and activating with this raw material 2 o 3 , specific surface 120~160m 2 / g, the percentage of >100nm pores accounted for more than 50% of the total pore volume, and its quality has reached the international advanced level, but the equipment of this method is seriously corroded, the environment is polluted, and the production is limited; 2 -Al 2 (SO 4 ) 3 The preparation of activated alumina as a raw material has the advantages of low cost, less equipment corrosion, and easy wastewater treatment. It has attracted a large number of domestic and foreign researchers to conduct research, and has also applied for many patents. Most of its production process is neutralized and gelled→ Aging→Washing→Forming→Drying→Activation roasting and other steps, but due to different process conditions and hole expansion measures, the performance of the prepared alumina carrier is quite different
It can be seen from this that the main disadvantages of this method are: the primary particle size of the pseudoboehmite prepared in the process of neutralization and gelation is small, the specific surface area of ​​the product after roasting is high, and the pore distribution is unreasonable, especially the microstructure. The ratio of pores to mesopores is too large

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
  • Preparation process for large pore volume and light bulk density activated alumina

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] NaAlO 2 Solution preparation: under mechanical stirring, add 160g of caustic soda into 800ml of deionized water, then raise the temperature to boiling, slowly add 200g of aluminum hydroxide, after all dissolve, keep warm at 105-110°C for 4 hours, then cool down to room temperature naturally, add water Dubbed 1200ml100g / L solution calculated by alumina.

[0026] Al 2 (SO 4 ) 3 Solution preparation: under mechanical stirring, heat 1200ml deionized water to 60-70℃, then add 396gAl 2 (SO 4 ) 3 1·8H 2 O, after all dissolved, lower to room temperature, add water to make 1800ml33.3g / L solution calculated by alumina.

[0027]First add 1000ml of deionized water into a 5000ml stainless steel reaction kettle, heat it to 85°C under mechanical stirring, and then co-flow to form a gel. Stabilized NaAlO 2 Solution flow rate 3~25ml / min, adjust Al 2 (SO 4 ) 3 The flow rate of the solution is until the pH value of the solution is 8, and overflow begins after 30 minutes to kee...

Embodiment 2

[0031] NaAlO with a concentration of 150g / L as alumina 2 1200ml of solution and Al with a concentration of 50g / L in terms of alumina 2 (SO 4 ) 3 The 1800ml solution is continuously co-flowed into a gel in the neutralization tank to stabilize NaAlO 2 Solution flow rate 3~25ml / min, adjust Al 2 (SO 4 ) 3 Solution flow rate until the pH value of the solution is 9, and the temperature is stable at 75°C. After 30 minutes, overflow begins to keep the liquid level of the neutralization tank stable. After neutralization, it is aged for 30 minutes. Other conditions are the same as in Example 1 to obtain γ-Al 2 o 3 LS 3 . LS is given in Table 1 3 physical properties.

[0032] Example 2 comparative example:

[0033] According to the method of Example 2, the difference is that the dried pellets are not loaded into the activation furnace for steam treatment, but are directly calcined in the muffle furnace to obtain γ-Al 2 o 3 LS 4 . LS is given in Table 1 4 physical properti...

Embodiment 3

[0035] NaAlO with a concentration of 200g / L as alumina 2 1200ml of solution and Al with a concentration of 67.7g / L in terms of alumina 2 (SO 4 ) 3 The 1800ml solution is continuously co-flowed into a gel in the neutralization tank to stabilize NaAlO 2 Solution flow rate 3~25ml / min, adjust Al 2 (SO 4 ) 3 Solution flow rate until the pH value of the solution is 7, and the temperature is stable at 65 ° C. After 30 minutes, it begins to overflow, and the liquid level of the neutralization tank is kept stable. After the neutralization is completed, it is aged for 90 minutes. Other conditions are the same as in Example 1 to obtain γ-Al 2 o 3 LS 5 . LS is given in Table 1 5 physical properties.

[0036] Example 3 comparative example:

[0037] According to the method of Example 3, the difference is that the dried pellets are not loaded into the activation furnace for steam treatment, but are directly calcined in the muffle furnace to obtain γ-Al 2 o 3 LS 6 . LS is given...

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 relates to a preparation process for large pore volume and light bulk density activated alumina, and belongs to the technical field of activated alumina preparation. According to the process, an aluminum sulfate solution and a sodium aluminate solution form a glue in a stainless steel neutralization kettle through a continuous co-current flow method; then an aging treatment is performed for a certain time in a stainless steel aging washing tank; the resulting material is pressed to a plate and frame filter press with a material pressing pump to carry out continuous washing to prepare primary pseudo-boehmite particles with large grains; the removed filter cake is acidified, and proper amounts of a pore expanding agent and a surfactant are added during the acidification process to carry out forming; the formed wet balls are placed in a drying box to carry out drying; and the dried small balls are loaded into a calcination activation furnace to carry out high temperature calcination and pore expanding. The process of the present invention has characteristics of low cost and low equipment corrosion, can performs continuous washing cycle, and has advantages of low wastewater discharging, less pollution, and the like. With the process of the present invention, the production cycle can be reduced, the labor intensity can be reduced, and various performance indicators of the prepared gamma-Al2O3 can meet the international advanced level after pore expanding by water vapor.

Description

technical field [0001] The invention relates to the technical field of preparation technology of activated alumina, in particular to a preparation technology of activated alumina with large pore volume and light bulk ratio. Background technique [0002] γ-Al 2 o 3 As a kind of activated alumina, due to its characteristics of high temperature resistance, wear resistance, oxidation resistance and porosity, and its pore structure is adjustable, it is more and more widely used in industrial applications such as petrochemical, biochemical, membrane materials and fine ceramics. It is becoming more and more extensive, and people's research on it is getting more and more in-depth. Large pore volume, light bulk ratio γ-Al 2 o 3 Due to its unique pore distribution, its application in enzyme catalysis, dehydrogenation of long-chain alkanes and other industries has attracted great attention. At present, large pore volume and low density γ-Al are prepared at home and abroad 2 o 3 ...

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): C01F7/02
Inventor 李国印俞杰张海伦
Owner JIANGSU JINGJING NEW MATERIALS
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