Controllable synthesis method of all-silicon and high-silicon CHA molecular sieve membrane

A synthesis method and molecular sieve technology, applied in separation methods, chemical instruments and methods, membrane technology, etc., can solve problems such as waste of raw materials, poor uniformity, and difficulty in film thickness control, and achieve improved utilization, good separation performance, and reduced costs. Effect

Active Publication Date: 2020-08-14
SHANGHAI UNIV OF ENG SCI
View PDF17 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This has led to a series of problems, such as the complicated and poor uniformity of the mother liquor preparation process, resulting in poor reproducibility of molecular sieve membrane preparation, difficulty in film thickness control, etc.
At the same time, the use of super-concentrated mother liquor also leads to a great waste of raw materials

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
  • Controllable synthesis method of all-silicon and high-silicon CHA molecular sieve membrane
  • Controllable synthesis method of all-silicon and high-silicon CHA molecular sieve membrane
  • Controllable synthesis method of all-silicon and high-silicon CHA molecular sieve membrane

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0055] A controllable synthesis method of all-silicon and high-silicon CHA molecular sieve membranes, the all-silicon CHA seed is loaded on a porous carrier, ammonium hexafluorosilicate or ordinary silicon source + fluoride is used as the silicon source, trimethyl hydroxide Adamantane ammonium is used as a template to configure the synthesis mother liquor, and the CHA molecular sieve membrane is prepared by traditional hydrothermal synthesis method or atom economical synthesis method. In the traditional hydrothermal synthesis method, the carrier tube loaded with all-silicon CHA seed crystals is directly placed in the CHA molecular sieve membrane synthesis mother liquor for hydrothermal crystallization. In atom-economic synthesis, the carrier tube loaded with all-silicon CHA seed crystals is taken out after immersion in the mother liquor of molecular sieve membrane synthesis, and then crystallized in a crystallization kettle with only a small amount of mother liquor of molecular...

Embodiment 1

[0064] A controllable synthesis method of an all-silicon CHA molecular sieve membrane, the specific steps are as follows:

[0065] Step 1: Mix ethyl orthosilicate and N,N,N-trimethyl-1-adamantyl ammonium hydroxide, stir for 4 hours, then place in an oven at 80 degrees Celsius to remove excess water and ethanol, then Add hydrofluoric acid, stir to obtain the seed crystal synthesis mother liquor, the SiO in the mother liquor 2 , HF, trimethyladamantyl ammonium hydroxide (TMAdaOH) and H 2 The molar ratio of O is 1.0:0.5:0.5:3. Crystallize at 453K for 48 hours to obtain all-silicon CHA molecular sieve seed crystals. The molecular sieve seed crystal is relatively large, about 8 microns, and after ball milling, the crystal is crushed to below 500 nanometers;

[0066] Step 2: Select a porous ceramic tube with a pore size of 100nm as the porous carrier, seal both ends of the carrier with glaze, wash and dry, seal the outer surface with PTFE tape, and disperse the ball-milled seed c...

Embodiment 2

[0076] The difference from Example 1 is that in step 4, heating in an oven at 160° C. for 6 hours.

[0077] The surface and profile of gained CHA molecular sieve membrane are as follows figure 2 As shown in the figure, it can be seen from the figure that the surface of the carrier is completely covered by square CHA crystals, and the cross-linking between the crystals is perfect (see figure a); the thickness of the film is relatively uniform, about 3.5 microns (see figure b).

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 sizeaaaaaaaaaa
particle diameteraaaaaaaaaa
pore sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to a controllable synthesis method of an all-silicon and high-silicon CHA molecular sieve membrane. The method comprises the following steps: taking N, N, N-trimethyl-1-adamantylammonium hydroxide (TMAdaOH) as a template agent, taking ammonium hexafluorosilicate, or a common silicon source and fluoride as silicon sources, and synthesizing the all-silicon and high-silicon CHAmolecular sieve membrane in a dilute solution with H2O / SiO2 of about 30. Meanwhile, an atomic economic synthesis method is developed and is also called sol-free synthesis, so that the use of a largeamount of mother liquor in traditional hydrothermal synthesis is avoided, the utilization rate of raw materials is greatly increased, and the cost for preparing the membrane is reduced. The thicknessof the prepared all-silicon and high-silicon CHA molecular sieve membrane is less than 1 micron, and the all-silicon and high-silicon CHA molecular sieve membrane has excellent CO2-CH4 separation performances.

Description

technical field [0001] The invention relates to the field of molecular sieve membranes, in particular to a controllable synthesis method of all-silicon and high-silicon CHA molecular sieve membranes. Background technique [0002] Molecular sieve membrane is obtained by preparing a layer of continuous, dense and uniform molecular sieve on a porous carrier. Because molecular sieve membranes have the advantages of uniform pore size, high temperature resistance, chemical solvent resistance, and ion exchange, they have great application potential in the fields of membrane catalytic reactions, gas separation, liquid pervaporation separation, and environmental protection. For example, in CO 2 In the field of removal, because the membrane separation device has the advantages of low energy consumption, continuous operation, low equipment investment, small volume, and easy maintenance, it is very suitable for high CO 2 The harsh separation environment of content. [0003] At presen...

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): B01D71/02B01D67/00C01B39/06C01B39/08B01D53/22
CPCB01D71/028C01B39/06C01B39/08B01D67/0044B01D67/0051B01D53/228C01P2004/03Y02P20/151
Inventor 张延风邱恒娥孔雪
Owner SHANGHAI UNIV OF ENG SCI
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