A method of accelerating solvent extraction to rapidly prepare airgel

A technology to accelerate solvents and aerogels, applied in chemical instruments and methods, inorganic chemistry, silicon compounds, etc., can solve the problems of low quality airgel powder, limited application fields, and prone to salting out, etc., to reduce production risks , Simplify the process and shorten the production cycle

Active Publication Date: 2021-07-16
浙江岩谷科技有限公司
View PDF29 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the existence of ions, this method greatly slows down the speed of surface silanization treatment. It is only suitable for the preparation of airgel powder, and the application field is very limited. Due to the incomplete removal of ions, there are still a large amount of residues in the gel powder. Ions, salting-out phenomenon is very easy to occur during storage, resulting in SiO 2 Airgel powder is of low quality and poor performance

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

[0037] A method for rapidly preparing airgel through accelerated solvent extraction, comprising the steps of:

[0038] At room temperature, mix sodium silicate and water at a volume ratio of 1:3, add to 20% sulfuric acid solution, make the pH reach 5.0, and form a gel after 30s. After the gel is crushed, put it into a supercritical extraction kettle, pump in alcohol with a volume concentration of 10% at 100°C, and control the absolute pressure of the supercritical extraction kettle to not be lower than 0.25MPa. After the alcohol is immersed in the gel, pump in the volume concentration At the same time, pump out the low-concentration alcohol in the reactor at the same rate to keep the alcohol level in the extraction tank constant, so that the alcohol concentration in the reactor will gradually increase from 10% to 90% within 30 minutes. %, stop the pump, after maintaining for 5min, pump out the alcohol, and then carry out CO 2 Supercritical drying to obtain hydrophilic SiO 2 ...

Embodiment 2

[0040] A method for rapidly preparing airgel through accelerated solvent extraction, comprising the steps of:

[0041] Mix sodium silicate and water at a volume ratio of 1:3 at room temperature, add 20% sulfuric acid solution to make the pH reach 10.2, pour the mixed solution into a mold with a 10mm thick glass fiber mat, and form a gel after 2 minutes. glue. Put the composite material into a supercritical extraction kettle, pump in alcohol with a mass concentration of 20% at 120°C, and control the absolute pressure of the supercritical extraction kettle to not be lower than 0.45MPa. After the alcohol is immersed in the composite material, pump water and mass Alcohol with a concentration of 92%, the ratio of water and alcohol is controlled by a flowmeter, so that the mass concentration of the two is gradually increased from 50% to 92% after being mixed by a pipeline mixer, and then enters the supercritical extraction tank, and the low concentration in the reactor is Pump out ...

Embodiment 3

[0043] Mix sodium silicate and water at a volume ratio of 1:4 at room temperature, add to 6% oxalic acid solution to make the pH reach 5.5, pour the mixture into a mold with a 6mm thick glass fiber mat, and form after 2 minutes gel. Put the composite material into a supercritical extraction kettle, pump in an aqueous solution of acetone with a volume concentration of 20% at 85°C, and control the absolute pressure of the supercritical extraction kettle to not be lower than 0.25MPa. Pump out the low-concentration acetone aqueous solution in the reactor at the same rate, so that the acetone concentration in the reactor gradually increases from 20% to 90% within 30 minutes, stop the pump, and after maintaining for 8 minutes, pump out the acetone, and then clean the reactor. Composite materials in CO 2 Supercritical drying to obtain hydrophilic SiO 2 Airgel composites.

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
compressive strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for rapidly preparing airgel by accelerating solvent extraction, which comprises the following steps: (1) mixing and diluting a quantitative inorganic silicon source with water, adding a quantitative acid to form a salt-containing silica sol, and passing through a period of Forming a gel after a period of time; (2) performing accelerated solvent extraction on the gel obtained in step (1) with an aqueous solution of an organic solvent whose concentration increases with time; (3) drying the gel obtained in step (2). The invention provides a method for preparing airgel with simple process, short production cycle and low energy consumption. The airgel produced has the characteristics of complete structure, low thermal conductivity and good mechanical strength.

Description

technical field [0001] The invention relates to the technical field of manufacturing nanoporous airgel materials, in particular to a method for rapidly preparing airgel by accelerating solvent extraction. Background technique [0002] SiO 2 Airgel is currently one of the most widely concerned thermal insulation materials, which is composed of highly cross-linked SiO 2 The porous material prepared by the gel through a special drying process has a three-dimensional network structure, and its skeleton and pore structure are at the nanometer level. The unique structure makes SiO 2 Airgel material has extremely low thermal conductivity, can effectively inhibit heat conduction and heat convection, and is considered to be the solid material with the best thermal insulation performance. [0003] Due to its great application potential, researchers from all over the world have invested in the development of various SiO2 2 Airgel preparation methods, the silicon sources used are al...

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): C01B33/158C01B33/154
CPCC01B33/154C01B33/1546C01B33/1585
Inventor 闫方闵阳徐君赵科仁项柳燕张蓉艳
Owner 浙江岩谷科技有限公司
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