Method for producing beta zeolite
Provided is a method for producing a beta zeolite, which is a seed crystal addition method that is capable of reducing the environmental load as much as possible. A method for producing a beta zeolite according to the present invention comprises a step wherein a reaction mixture that contains a silica source, an alumina source, an alkali source and water and a seed crystal that is composed of a beta zeolite are mixed with each other and heated. A beta zeolite which comprises particles having a particle size of 10 μm or less in an amount of 90% or more on a volume basis in the particle size distribution as determined by a laser diffraction/scattering particle size distribution measuring method, and which is synthesized without using an organic structure-directing agent is used as the seed crystal.
1. A method for producing a beta zeolite, comprising:
mixing a reaction mixture comprising a silica source, an alumina source, an alkali source and water with a seed crystal comprising a beta zeolite and heating the mixture,
wherein a beta zeolite synthesized without using an organic structure-directing agent and comprising particles having a particle size of 10 μm or less in an amount of 90% or more on a volume basis in the particle size distribution as determined by a laser diffraction/scattering particle size distribution measuring method is used as the seed crystal.
2. The method for producing a beta zeolite according to claim 1 , wherein a beta zeolite synthesized using an organic structure defining agent and calcined is further used as the seed crystal.
3. The method for producing a beta zeolite according to claim 2 , wherein, in the seed crystal, the content of the beta zeolite synthesized without using an organic structure defining agent is 10% by mass or more and less than 100% by mass.
4. The method for producing a beta zeolite according to claim 3 , wherein compositions of the reaction mixture represented by molar ratios are in ranges:
SiO 2 /Al 2 O 3 =8 to 40
Na 2 O/SiO 2 =0.05 to 0.3
H 2 O/SiO 2 =5 to 50.
5. The method for producing a beta zeolite according to claim 3 , wherein the seed crystal is mixed into the reaction mixture in a state of solid-liquid mixture.
6. The method for producing a beta zeolite according to claim 3 , wherein the mixed amount of the seed crystal is 1% by mass or more and 30% by mass or less relative to the mass of the silica source contained in the reaction mixture.
7. The method for producing a beta zeolite according to claim 3 , wherein the SiO 2 /Al 2 O 3 ratio of the seed crystal is 8 or more and 30 or less.
8. The method for producing a beta zeolite according to claim 2 , wherein compositions of the reaction mixture represented by molar ratios are in ranges:
SiO 2 /Al 2 O 3 =8 to 40
Na 2 O/SiO 2 =0.05 to 0.3
H 2 O/SiO 2 =5 to 50 .
9. The method for producing a beta zeolite according to claim 2 , wherein the seed crystal is mixed into the reaction mixture in a state of solid-liquid mixture.
10. The method for producing a beta zeolite according to claim 2 , wherein the mixed amount of the seed crystal is 1% by mass or more and 30% by mass or less relative to the mass of the silica source contained in the reaction mixture.
11. The method for producing a beta zeolite according to claim 2 , wherein the SiO 2 /Al 2 O 3 ratio of the seed crystal is 8 or more and 30 or less.
12. The method for producing a beta zeolite according to claim 1 , wherein compositions of the reaction mixture represented by molar ratios are in ranges:
SiO 2 /Al 2 O 3 =8 to 40
Na 2 O/SiO 2 =0.05 to 0.3
H 2 O/SiO 2 =5 to 50.
13. The method for producing a beta zeolite according to claim 12 , wherein the seed crystal is mixed into the reaction mixture in a state of solid-liquid mixture.
14. The method for producing a beta zeolite according to claim 12 , wherein the mixed amount of the seed crystal is 1% by mass or more and 30% by mass or less relative to the mass of the silica source contained in the reaction mixture.
15. The method for producing a beta zeolite according to claim 12 , wherein the SiO 2 /Al 2 O 3 ratio of the seed crystal is 8 or more and 30 or less.
16. The method for producing a beta zeolite according to claim 1 , wherein the seed crystal is mixed into the reaction mixture in a state of solid-liquid mixture.
17. The method for producing a beta zeolite according to claim 16 , wherein the mixed amount of the seed crystal is 1% by mass or more and 30% by mass or less relative to the mass of the silica source contained in the reaction mixture.
18. The method for producing a beta zeolite according to claim 16 , wherein the SiO 2 /Al 2 O 3 ratio of the seed crystal is 8 or more and 30 or less.
19. The method for producing a beta zeolite according to claim 1 , wherein the mixed amount of the seed crystal is 1% by mass or more and 30% by mass or less relative to the mass of the silica source contained in the reaction mixture.
20. The method for producing a beta zeolite according to claim 1 , wherein the SiO 2 /Al 2 O 3 ratio of the seed crystal is 8 or more and 30 or less.