Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

A kind of synthetic method of titanium-silicon molecular sieve with high skeleton titanium content

A technology of titanium-silicon molecular sieve and synthesis method, which is applied in the direction of molecular sieve catalysts, chemical instruments and methods, crystalline aluminosilicate zeolites, etc., can solve problems such as increasing production process and cost, increasing maintenance costs, and equipment corrosion, and avoiding The formation of non-framework titanium, the effect of reducing the mismatch of hydrolysis rate and reducing the loss of framework titanium

Active Publication Date: 2016-08-24
CHINA TIANCHEN ENG +1
View PDF9 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

One is to modify the prepared TS-1 titanium-silicon molecular sieve, mainly using the modification of inorganic base or organic base to generate holes in TS-1 to promote the diffusion of reactants and products. Adding a separate modification process after completion will increase the production process and cost. The addition of alkaline substances will often introduce new impurities, which is not conducive to the separation and purification of TS-1 products, and may also cause certain corrosion to equipment role, increased maintenance costs
The second is to control the synthesis conditions of TS-1 titanium-silicon molecular sieve. It is generally believed that the reason for the generation of non-skeletal titanium is that the hydrolysis speed of the silicon source and the titanium source are inconsistent, which makes it very difficult to accurately grasp the hydrolysis conditions and make them match each other, resulting in local inhomogeneity. In the improved preparation process, the silicon source is often pre-hydrolyzed to a certain extent, or fatty acids are added to the titanium source to slow down the hydrolysis rate of the titanium source, so that the hydrolysis rate of the silicon source and the titanium source are as consistent as possible. Although some progress has been made in inhibiting the formation of non-framework titanium, the generation of non-framework titanium has not been completely avoided.

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
  • A kind of synthetic method of titanium-silicon molecular sieve with high skeleton titanium content

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] (1) After mixing the silicon source and the titanium source, add them to the aqueous solution of tetrapropylammonium hydroxide and stir them fully, and hydrolyze them for 0.5h at 0°C to obtain the hydrolyzed solution of the silicon source and the titanium source, the molar composition of which is Si:Ti: Tetrapropyl ammonium hydroxide=1: 0.01: 0.03, the massfraction of tetrapropyl ammonium hydroxide relative to water is 3%;

[0021] (2) The obtained hydrolysis solution is dealcoholized step by step, first dealcoholized at 50°C until the mass fraction of tetrapropylammonium hydroxide relative to water is 15%, and then dealcoholized at 61°C to tetrapropylammonium hydroxide Ammonium hydroxide is 21% relative to the massfraction of water;

[0022] (3) After alcohol removal, the mother liquor is put into a closed reaction kettle for pre-crystallization at 100° C. for 0.5 h, and then a certain amount of aliphatic amine compound n-butylamine is added, wherein the molar ratio Si...

Embodiment 2

[0025] (1) After mixing the silicon source and the titanium source, add them to the aqueous solution of tetraethylammonium hydroxide and stir fully, hydrolyze for 5 hours at 50° C. to obtain the hydrolysis solution of the silicon source and the titanium source, and its molar composition is Si: Ti: tetra Ethyl ammonium hydroxide=1: 0.05: 0.6, the mass fraction of tetraethyl ammonium hydroxide relative to water is 14%;

[0026] (2) The obtained hydrolysis solution is dealcoholized step by step, first dealcoholized at 60°C to tetraethylammonium hydroxide relative to the mass fraction of water is 20%, and then dealcoholized at 85°C to tetraethylammonium hydroxide Ammonium hydroxide is 50% relative to the massfraction of water;

[0027] (3) After alcohol removal, the mother liquor is put into a closed reaction kettle for pre-crystallization at 150° C. for 10 h, and then a certain amount of ethylamine is added, wherein the molar ratio Si:ethylamine=1:0.6;

[0028] (4) Continue to p...

Embodiment 3

[0030] (1) After mixing the silicon source and the titanium source, add them to the aqueous solution of tetramethylammonium hydroxide and stir fully, and hydrolyze for 1 hour at 50° C. to obtain the hydrolyzed solution of the silicon source and the titanium source, and its molar composition is Si: Ti: tetramethylammonium hydroxide Methyl ammonium hydroxide=1: 0.03: 0.2, the mass fraction of tetramethyl ammonium hydroxide relative to water is 10%;

[0031] (2) The obtained hydrolysis solution is dealcoholized step by step, first dealcoholized at 60°C to a mass fraction of tetramethylammonium hydroxide relative to water of 15%, and then dealcoholized at 80°C to tetramethylammonium hydroxide Ammonium hydroxide is 45% relative to the massfraction of water;

[0032] (3) After alcohol removal, the mother liquor is put into a closed reaction kettle for pre-crystallization at 120° C. for 4 hours, and then a certain amount of tri-n-propylamine is added, wherein the molar ratio Si:tri-n...

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 synthesis method of a titanium-silicon molecular sieve with a high content of framework titanium. Due to the steps of dealcoholizing stepwise, pre-crystallizing, then adding an appropriate amount of a fatty amine compound into a molecular sieve, and crystallizing hydrothermally further, the loss of framework titanium in the process of synthesizing the molecular sieve can be reduced and the formation of non-framework titanium can be avoided.

Description

technical field [0001] The invention belongs to the technical field of petrochemical catalysis, and in particular relates to a preparation method of a TS-1 titanium-silicon molecular sieve with an MFI structure. Background technique [0002] Titanium-silicon molecular sieve TS-1 is a Pentasil-type heteroatom molecular sieve containing skeleton titanium atoms. In addition to maintaining the topological structure of the original MFI molecular sieve, TS-1 has a special skeleton Si-O-Ti bond due to the uniform distribution of titanium atoms in the skeleton, which makes it have both catalytic oxidation activity and shape-selective catalytic performance. [0003] In 1981, USP4410501 disclosed the synthesis method of TS-1 for the first time. After 40 years of continuous development and research, the hydrothermal synthesis of TS-1 has formed two systems, one is using tetrapropylammonium hydroxide (TPAOH ) as a template to synthesize titanium-silicon molecular sieve, which is calle...

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): C01B39/08B01J29/89C07C249/04C07C251/44
Inventor 杨克俭袁海朋杨琦武
Owner CHINA TIANCHEN ENG
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products