초록

This invention relates to a high activity ZSM-48. More particularly, a high activity ZSM-48 with defined purity is prepared, the ZSM-48 being free of non-ZSM-48 seed crystals and ZSM-50.

대표청구항 ▼

The invention claimed is: 1. A composition comprising ZSM-48 crystals having a silica:alumina molar ratio of 110 or less that is free of non-ZSM-48 seed crystals and free of ZSM-50, wherein the ZSM-48 crystals are free of crystals having a fibrous morphology. 2. The composition of claim 1, where

The invention claimed is: 1. A composition comprising ZSM-48 crystals having a silica:alumina molar ratio of 110 or less that is free of non-ZSM-48 seed crystals and free of ZSM-50, wherein the ZSM-48 crystals are free of crystals having a fibrous morphology. 2. The composition of claim 1, wherein the ZSM-48 crystals are free of crystals having a needle-like morphology. 3. The composition of claim 1, wherein the ZSM-48 crystals are free of Kenyaite. 4. The composition of claim 1, wherein the ZSM-48 crystals have a silica:alumina ratio of less than 100. 5. The composition of claim 1, wherein the ZSM-48 crystals are free of non-ZSM-48 crystals. 6. The composition of claim 1, further comprising at least one of a binder and hydrogenation metal. 7. The composition of claim 6, wherein the hydrogenation metal is a noble metal. 8. The composition of claim 1, wherein the ZSM-48 crystals are Na-form, H-form, or as-synthesized. 9. The composition of claim 1, wherein the ZSM-48 crystals are made from a mixture containing a hexamethonium structure directing agent in a structure directing agent:silica molar ratio from 0.01 to 0.05. 10. The composition of claim 9, wherein the structure directing agent:silica molar ratio in the mixture is from 0.015 to 0.025. 11. The composition of claim 1, wherein the as-synthesized ZSM-48 crystals have a silica:alumina ratio of 100 or less. 12. The composition of claim 1, wherein the as-synthesized ZSM-48 crystals have a silica:alumina ratio of at least 70. 13. A method for making as-synthesized ZSM-48 crystals containing a hexamethonium structure directing agent, wherein the as-synthesized ZSM-48 crystals are free of ZSM-50 and non-ZSM-48 seed crystals, the method comprising: preparing an aqueous mixture of silica or silicate salt, alumina or aluminate salt, hexamethonium salt and alkali base wherein the mixture has the following molar ratios: silica:alumina from 70 to 110, base:silica from 0.1 to 0.3 and hexamethonium salt:silica from 0.01 to 0.05; and heating the mixture with stirring for a time and temperature sufficient for crystal formation. 14. The method of claim 13, wherein the mixture has a base:silica molar ratio is from 0.14 to 0.18. 15. The method of claim 13, wherein the mixture has a hexamethonium salt:silica molar ratio is from 0.015 to 0.025. 16. The method of claim 13, wherein the as-synthesized ZSM-48 crystals are calcined to remove the hexamethonium structure directing agent. 17. The method of claim 13, wherein the as-synthesized ZSM-48 crystals are combined with at least one of a binder and metal hydrogenation component. 18. The method of claim 13, wherein the as-synthesized ZSM-48 crystals are prepared using ZSM-48 seed crystals. 19. The method of claim 13, wherein the as-synthesized ZSM-48 crystals have a silica:alumina ratio of 70-110.