Method for preparing nano silicon dioxide by vapor phase process

A technology of nano-silica and gas-phase method, which is applied in the direction of silicon dioxide and silicon oxide, can solve the problem that the output cannot meet the market demand, and achieve the effect of low raw material cost, high reinforcing effect and simple process

Inactive Publication Date: 2010-06-23
SHANGHAI KEWANG NEW MATERIAL RES CENT
View PDF0 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Since domestic production cannot meet market demand...

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

[0019] 1. Pretreatment of fly ash: soak the fly ash in 15% to 25% dilute sulfuric acid for 0.1 to 3 hours, and set aside.

[0020] 2. Mix 100kg of fly ash with 100kg~300kg of CaF 2 Put them into the reaction kettle respectively, stir and mix evenly, then add 10kg~400kg of concentrated H to the reaction kettle dropwise 2 SO 4 , Stir the reaction at -4°C to 25°C, and introduce the generated silicon tetrafluoride gas into the hydrolysis device through a pipeline.

[0021] 3. Add 10kg to 100kg of surface dispersant to the hydrolysis device for hydrolysis to produce a white solid.

[0022] 4. Filter the white solid with a 400-mesh plate and frame filter press, and then dry it to obtain pure white and loose amorphous nano-SiO 2 ·nH 2 O.

Embodiment 2

[0024] 1. Pretreatment of fly ash: soak the fly ash in 15% to 25% dilute sulfuric acid for 0.1 to 3 hours, and set aside.

[0025] 2. Combine 100kg fly ash with 100kg~300kg concentrated H 2 SO 4 Put them into iron reaction kettles respectively, slowly add 10-100kg of anhydrous hydrofluoric acid at -4°C to 25°C, and guide the generated silicon tetrafluoride gas into the hydrolysis device through pipelines.

[0026] 3. Add 10kg to 100kg of surface dispersant to the hydrolysis device for hydrolysis to produce a white solid.

[0027] 4. Filter the white solid with a 400-mesh plate and frame filter press, and then dry it to obtain pure white and loose amorphous nano-SiO 2 ·nH 2 O.

[0028] In the above two methods, the surface dispersant can be one or more of ethanol, ethylene glycol, glycerol, sodium lauryl sulfate and citric acid, and the diameters of 6-nm and 10-nm respectively can be obtained. 15nm, 20-30nm and 80-100nm amorphous nano-SiO 2 ·nH 2 O.

[0029] Wherein, 40...

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 nano silicon dioxide by a vapor phase process, which is characterized in that fly ash is hydrolyzed to produce silica gel, and the silica gel is dried to obtain the nano silicon dioxide. The method hydrolyzes silicon tetrafluoride in the fly ash to generate silica gel, and the silica gel is dried to obtain the nano silicon dioxide. The method has the advantages of low material cost, simple technique and easy production control. The obtained silicon dioxide is a white amorphous flocculent translucent solid, is innoxious, and has a large specific area (100-400 m<2>/g). The production has the advantages of high chemical purity, high dispersibility and higher surface activity.

Description

technical field [0001] The present invention relates to silicon dioxide, in particular, the present invention relates to a method for preparing amorphous nano silicon dioxide. Background technique [0002] The scientific name of white carbon black is hydrated silica, and its molecular formula is SiO 2 ·nH 2 O, is fine powder or ultrafine particle silicon dioxide, the primary particle size is less than 0.0003mm, the specific gravity is 2.319-2.653, and the melting point is 1750°C. Hydrated silica was developed in Germany in the 1940s as a substitute for carbon black, and has been widely used in industrial sectors such as rubber, shoemaking, paint, papermaking, synthetic resin and oil, among which rubber and shoemaking industries are Maximum dosage. [0003] Fumed silica is a fine chemical with high technical content, and its price is SiO 2 The highest value of the species. The business related to this product is spread all over the world, but its production is highly con...

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): C01B33/12
Inventor 徐守启
Owner SHANGHAI KEWANG NEW MATERIAL RES CENT
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