Preparation method of nanocrystalline zsm-5 zeolite cluster and nanocrystalline zsm-5 zeolite cluster prepared by the method
A ZSM-5, nanocrystalline technology, applied in the direction of crystalline aluminosilicate zeolite, borocarbonane silicone crystalline aluminosilicate zeolite, etc., can solve the problems of high-speed centrifugation, template price restriction, catalyst deactivation and so on
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
preparation example Construction
[0025] In the first aspect of the present invention, a kind of preparation method of nanocrystalline ZSM-5 zeolite cluster is provided, and the method comprises the following steps:
[0026] 1) Preparation of high-concentration precursor solution: mix ethyl silicate and aluminum isopropoxide and add a certain amount of deionized water, stir evenly, add tetrapropylammonium hydroxide to the above system, at 20-60°C Stir until clear liquid;
[0027] 2) Low-temperature hydrothermal nucleation stage: Stir the high-concentration precursor solution obtained in step 1) in an oil bath at 95-100°C for 1-2 days to generate a large number of nanocrystals, and the number of nanocrystals is controlled in the system The concentration of NaOH, the molar ratio of the system is: 1 mole of aluminum isopropoxide: 50 moles of ethyl silicate: 9 moles of tetrapropyl ammonium hydroxide: 7.5-12 moles of sodium hydroxide: 2300-2400 moles of water, the reaction vessel It is a Duran bottle with good sea...
Embodiment 1
[0040]Mix 0.3066g of aluminum isopropoxide and 15.624g of ethyl silicate and add 26g of water to stir at room temperature for 1 hour, then add 10.98g of tetrapropylammonium hydroxide (25% by weight) dropwise, and then add 0.72g of NaOH dropwise after 2 hours The mixed solution with 30g of water was stirred at 40°C for 3-6 hours to become a clear solution, and transferred to an oil bath at 100°C to continue stirring for 2 days. The above reaction was carried out in a 250ml Duran bottle with good sealing performance. After the above solution was cooled to room temperature, 90ml of water and 24g of ethanol were added, and the mixed system was placed in a hydrothermal kettle at 150°C to continue crystallization for 24 hours, and the powder obtained by suction filtration was dried in an oven at 100°C for 10 hours, and the system The molar ratio is: 1 mole of aluminum isopropoxide: 50 moles of ethyl silicate: 9 moles of tetrapropylammonium hydroxide: 12 moles of sodium hydroxide: 174...
Embodiment 2-3
[0042] According to the method of Example 1, the consumption of NaOH was adjusted to 0.54g and 0.45g respectively, keeping other parameters unchanged. The SEM figures of embodiment 2 and embodiment 3 are respectively figure 1 In C, D and E, F, as shown, similarly, the obtained material is a nanocrystalline cluster with a particle size of 500-800nm, and a nanocrystalline particle size of 30-80nm forms a near-spherical cluster according to a certain orientation. The TEM (transmission electron microscope) and HRTEM (high resolution transmission electron microscope) pictures of embodiment 2 are shown in figure 2 as shown, figure 2 The HRTEM and electron diffraction patterns show that the small grains grow into ellipsoidal clusters with a size of about 500nm according to a certain orientation. It can be seen that when NaOH is adjusted within a certain range, the microstructure of the material is still nanocrystalline clusters, and high concentration of sodium hydroxide can redu...
PUM
| Property | Measurement | Unit |
|---|---|---|
| specific surface area | aaaaa | aaaaa |
| particle diameter | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More