Silicon dioxide aerogel, as well as continuous constant-pressure drying preparation method and system thereof

A silicon dioxide and atmospheric pressure drying technology, which is applied in the direction of silicon dioxide and silicon oxide, can solve the problems of cumbersome operation and achieve the effects of reduced preparation time, low energy consumption and easy continuous process

Active Publication Date: 2015-11-04
苏州同玄新材料有限公司
View PDF10 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, since normal pressure drying generally requires multi-step gel channel solvent exchange and surface hydrophobization treatment, the general preparation cycle is more than one week, and the operation is cumbersome.

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
  • Silicon dioxide aerogel, as well as continuous constant-pressure drying preparation method and system thereof
  • Silicon dioxide aerogel, as well as continuous constant-pressure drying preparation method and system thereof
  • Silicon dioxide aerogel, as well as continuous constant-pressure drying preparation method and system thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0038] Further, the preparation method includes: mixing the silicon source, water, catalyst and dryness control agent to homogenize the gel, then crushing the wet gel, and then replacing it with alcohol and liquid alkane, modifying it with a hydrophobic agent, and then separating Hydrophobic alkane gel is dried and sintered to obtain hydrophobic airgel powder.

[0039] In a preferred embodiment, the preparation method may include:

[0040] (1) Mix the silicon source, water, catalyst and drying control agent uniformly to form a mixed liquid;

[0041] (2) Transfer the mixed liquid obtained in step (1) to the conveyer belt, and form a gel during the conveying process, then input the gel into a crusher, and crush it to form granules or powder;

[0042] (3) input the gel particles or powder obtained in step (2) into the stirring tank, and input water at the same time, and heat and stir to obtain the gel-water slurry;

[0043] (4) The gel-water slurry obtained in step (3) is trans...

Embodiment 1

[0077] Example 1 see figure 1 , the method for preparing silica aerogel by continuous atmospheric pressure drying may comprise the steps:

[0078] 1) Water glass (silicon dioxide content 30wt%, modulus 2.3) was added to the continuous stirring system at a rate of 4 L / h, water at 16 L / h, and nitric acid at a rate of 0.5 L / h.

[0079] 2) After stirring, it enters the conveying system to form a gel, and the conveyor belt conveys the gel to the crusher, which becomes a gel powder after being crushed.

[0080] 3) The gel powder prepared in step (2) was pumped into the reactor at a rate of 20 L / h, and deionized water was pumped into the stirred reactor 1 at a rate of 80 L / h at the same time. The stirring speed of the reactor was 100 rpm, and the temperature of the reactor was 90°C.

[0081] 4) The water-hydrogel reaction product prepared in step (3) is pumped out at a rate of 100 L / h, and enters the drum vacuum filter 1, and is filtered and separated into hydrogel and water waste ...

Embodiment 2

[0088] (1) SiO 2 Preparation of gel particles: mix water glass (5% silicon content), water, and polyvinyl alcohol (2%), adjust the pH value between 4-6 with sulfuric acid, and let stand for 30 minutes to form a gel. The gel is mechanically stirred to obtain gel particles with a size between 0.01 mm and 0.5 mm.

[0089] (2) Solvent exchange: Gel particles and water (1:1, unless otherwise specified, the volume ratio below) are put into a stirring tank, the stirring speed is 100rpm to 500rpm, and the temperature is from room temperature to 90°C. After stirring for 5 hours, vacuum filtration was performed to obtain hydrogel particles. Put hydrogel particles and methanol or ethanol (1:1) into a stirred tank and stir, heat to 5°C below the boiling point of alcohol, stir for 1 hour, and vacuum filter to obtain alcohol gel. Alcohol gel particles and n-hexane (1:1) were put into a stirred tank and stirred, heated to 5°C below the boiling point of alcohol, stirred for 1 hour, and vacu...

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
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses slicon dioxide aerogel, as well as a continuous constant-pressure drying preparation method and a system thereof. The preparation method comprises the following steps of: using water glass, silicasol, silanol and the like which are relative low in price as silicon sources, uniformly mixing the silicon sources, water, a catalyst and a drying control agent to obtain a mixture, leaving gel to stand, crushing the wet gel into particles or powder, performing replacement with alcohol and liquid alkane, using a hydroghobing agent for modification, separating alkane gel, and finally, performing drying and sintering so as to obtain dewatering silicon dioxide aerogel. The silicon dioxide aerogel disclosed by the invention can realize continuous production, and is short in preparation period, small in pollution, low in cost and environment-friendly. The aerogel is powder or particles, the density is 0.04g/ml-0.3g/ml, the particle diameter is 0.1 mum-2mm, the specific surface is 500m<2>/g-1200m<2>/g, and the heat conductivity is 0.01W/mk-0.04W/mk.

Description

technical field [0001] The invention relates to a method for preparing a nanoporous airgel thermal insulation material, in particular to a method for preparing silica airgel by continuous atmospheric pressure drying, and belongs to the technical field of nanoporous materials. Background technique [0002] As a material in the form of an amorphous solid, airgel is a product obtained by replacing the internal solvent with air while maintaining the gel skeleton of the hydrogel, and its porosity can reach more than 90%. Therefore, airgel is also the lightest solid substance known at present. Due to its unique microstructure, aerogels have many excellent physical and chemical properties, such as low density, low thermal conductivity, low sound velocity transmission rate, high adsorption rate and so on. [0003] According to "Aerogel Handbook" ("Aerogel Handbook", Michel A.Aegerter, ISBN 978-1-4419-7477-8, Springer New York Dordrecht Heidelberg London), the preparation methods of...

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): C01B33/16
Inventor 张学同张尚权王锦
Owner 苏州同玄新材料有限公司
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