Methods to produce molecular sieves with LTA topology and compositions derived therefrom

1. A process for comprising hydrothermally treating an aqueous composition comprising:

(a) a source of a silicon oxide;

(b) an optional source of an aluminum oxide;

(c) an optional source of a germanium oxide;

(d) an optional source of a titanium oxide;

(e) an optional source of one or more of a boron oxide, gallium oxide, hafnium oxide, iron oxide, tin oxide, indium oxide, vanadium oxide, zinc oxide, zirconium oxide, or combination or mixture thereof;

(f) a mineralizing agent; and

(g) an organic structure directing agent (OSDA) comprising a substituted benzyl-3H-imidazol-1-ium cation of Formula (I):

and optionally a tetramethylammonium salt, under conditions effective to crystallize a crystalline microporous silicate solid of LTA topology;

wherein

R 1 , R 2 , and R 7 are independently C 1-6 alkyl;

R 3 , R 4 , R 5 , R 6 , R 8 , and R 9 are independently H or C 1-3 alkyl; and

the substituted benzyl-3H-imidazol-1-ium cation has an associated bromide, chloride, fluoride, iodide, nitrate, or hydroxide anion.

2. The process of claim 1 , wherein the OSDA comprises a 2,3-dialkyl-1-(4-alkyl-benzyl)-3H-imidazol-1-ium cation of Formula (IA):

wherein R 1 , R 2 , and R 7 are independently C 1-3 alkyl.

3. The process of claim 1 , wherein the OSDA comprises a 2,3-dimethyl-1-(4-methyl-benzyl)-3H-imidazol-1-ium cation of Formula (IB):

(2,3-dimethyl-1-(4-methyl-benzyl)-3H-imidazol-1-ium).

4. The process of claim 1 , wherein the aqueous composition comprises:

(b) the source of the aluminum oxide;

(c) the source of the germanium oxide;

(d) the source of the titanium oxide; or

(e) a combination of two or more of (b)-(d).

5. The process of claim 1 , wherein the hydrothermal treatment provides a crystalline microporous pure-silicate, aluminosilicate, germanosilicate, or titanosilicate solid of LTA topology.

6. The process of claim 1 , wherein:

(a) the source of the silicon oxide comprises a silicon alkoxide, a silicate, a silica hydrogel, silicic acid, fumed silica, colloidal silica, a tetra-alkyl orthosilicate, a silica hydroxide, a silicon alkoxide, or combination thereof;

(b) the source of the aluminum oxide, when present, comprises an alkoxide, hydroxide, or oxide of aluminum, a sodium aluminate, or combination thereof;

(c) the source of the germanium oxide, when present, comprises a alkali metal orthogermanate, containing discrete GeO 4 4− ions, GeO(OH) 3 − , GeO2(OH) 2 2− , [(Ge(OH) 4 ) 8 (OH) 3 ] 3− or neutral solutions of germanium dioxide containing Ge(OH) 4 , or an alkoxide or carboxylate derivative thereof; and

(d) the source of the titanium oxide, when present, comprises a titanium alkoxide, oxide, or hydroxy oxide.

7. The process of claim 1 , wherein the mineralizing agent comprises an aqueous alkali metal or alkaline earth metal hydroxide.

8. The process of claim 1 , wherein the mineralizing agent comprises hydrofluoric acid (HF).

9. The process of claim 1 , wherein the composition has:

(a) a molar ratio of the OSDA:Si is in a range of from 0.1 to 1;

(b) a molar ratio of Al:Si in a range of from 0 to 0.1, when the source of the aluminum oxide is present;

(c) a molar ratio of Ge:Si in a range of from 0 to 1, when the source of the germanium oxide is present;

(d) a molar ratio of Ti:Si in a range of from 0 to 0.1, when the source of the titanium oxide is present;

(e) a molar ratio of water:Si in a range of from about 2 to about 20; and

(f) a molar ratio of fluoride:Si in a range of from about 0.1 to about 0.75, when the mineralizing agent is HF.

10. The process of claim 9 , wherein the aqueous composition further comprises:

(b) the source of the aluminum oxide;

(c) the source of the germanium oxide;

(d) the source of the titanium oxide; or

(e) a combination of two or more of (b)-(d).

11. The process of claim 1 , wherein the conditions effective to crystallize a crystalline microporous solid of LTA topology include treatment of the respective hydrothermally treated aqueous composition at a temperature in a range of from 100° C. to 200° C. for a time in a range of from 3 to 40 days.

12. The process of claim 1 , further comprising isolating the crystalline microporous silicate solid of LTA topology.

13. The process of claim 12 , further comprising:

(a) heating the isolated crystalline microporous solid at a temperature in a range of from about 250° C. to about 450° C.;

(b) contacting the isolated crystalline microporous solid with ozone or other oxidizing agent at a temperature in a range of 100° C. to 200° C.; or

(c) heating the isolated crystalline microporous solid at a temperature in a range of from about 200° C. to about 600° C. in the presence of an alkali, alkaline earth, transition metal, rare earth metal, ammonium or alkylammonium salt;

for a time sufficient to form a dehydrated or an OSDA-depleted product.

14. The process of claim 13 , further comprising:

(a) treating the dehydrated or OSDA-depleted product with an aqueous alkali, alkaline earth, transition metal, rare earth metal, ammonium or alkylammonium salt; and/or

(b) treating the dehydrated or OSDA-depleted product with at least one type of transition metal or transition metal oxide.

15. A crystalline microporous silicate solid of LTA topology, prepared by the process of claimed 1 , containing within its pores an OSDA comprising a substituted benzyl-3H-imidazol-1-ium cation of Formula (I):

wherein

R 1 , R 2 , and R 7 are independently C 1-6 alkyl;

R 3 , R 4 , R 5 , R 6 , R 8 , and R 9 are independently H or C 1-3 alkyl.

16. The crystalline microporous silicate solid of LTA topology of claimed 15 , wherein the solid is:

(a) a pure-silicate;

(b) an aluminosilicate;

(c) a germanosilicate; or

(d) a titanosilicate.

17. The crystalline microporous silicate solid of LTA topology of claim 15 , wherein the OSDA comprises a 2,3-dimethyl-1-(4-methyl-benzyl)-3H-imidazol-1-ium cation of Formula (IB):

18. A crystalline microporous pure-silicate, aluminosilicate, germanosilicate, or titanosilicate solid of LTA topology prepared according to the process of claim 1 .

19. The crystalline microporous pure-silicate, aluminosilicate, germanosilicate, or titanosilicate solid of claim 18 , the solid exhibiting

a powder XRD pattern having at least five characteristic peaks selected from the group consisting of 7.6° ±0.3° 2-theta; 10.6° ±0.3° 2-theta; 13.0° ±0.3° 2-theta; 15.1° ±0.3° 2-theta; 21.4° ±0.3° 2-theta; 22.7° ±0.3° 2-theta; 25.1° ±0.3° 2-theta; 27.3° ±0.3° 2-theta; 28.3° ±0.3° 2-theta; and 31.3° ±0.3° 2-theta.

20. The crystalline microporous pure-silicate, aluminosilicate, germanosilicate, or titanosilicate solid of claim 18 , the solid exhibiting a powder XRD pattern having characteristic peaks at 7.6° ±0.3° 2-theta; 10.6° ±0.3° 2-theta; 13.0° ±0.3° 2-theta; 22.7 ° ±0.3° 2-theta; and 25.1° ±0.3° 2-theta.

21. The crystalline microporous pure-silicate of claim 18 exhibiting a 29 Si Bloch decay NMR spectrum having a single resonance at −113.3 ppm, relative to tetramethylsilane, consistent with the silicon being in a single T-site in the LTA structure.

22. The crystalline microporous aluminosilicate of claim 18 exhibiting an 27 Al MAS NMR spectrum consistent with the aluminum being in a tetrahedral environment.

23. The crystalline microporous silicate solid of LTA topology of claim 15 , wherein the OSDA comprises a 2,3-dialkyl-1-(4-alkyl-benzyl)-3H-imidazol-1-ium cation of Formula (IA):

wherein R 1 , R 2 , and R 7 are independently C 1-3 alkyl.

24. A composition comprising:

(a) a source of a silicon oxide;

(b) an optional source of an aluminum oxide;

(c) an optional source of a germanium oxide;

(d) an optional source of a titanium oxide;

(e) an optional source of one or more of a boron oxide, gallium oxide, hafnium oxide, iron oxide, tin oxide, titanium oxide, indium oxide, vanadium oxide, zinc oxide, zirconium oxide, or combination or mixture thereof;

(f) a mineralizing agent; and

(g) an organic structure directing agent (OSDA) comprising a substituted benzyl-3H-imidazol-1-ium cation of Formula (I):

and

(h) a compositionally consistent crystalline microporous silicate solid of LTA topology having the OSDA occluded in its micropores;

wherein

R 1 , R 2 , and R 7 are independently C 1-6 alkyl;

R 3 , R 4 , R 5 , R 6 , R 8 , and R 9 are independently H or C 1-3 alkyl; and

the substituted benzyl-3H-imidazol-1-ium cation has an associated bromide, chloride, fluoride, iodide, nitrate, or hydroxide anion.

25. The composition of claim 24 , wherein the aqueous composition comprises:

(b) the source of the aluminum oxide and a compositionally consistent crystalline microporous aluminosilicate solid of LTA topology;

(c) the source of the germanium oxide and a compositionally consistent crystalline microporous germanosilicate solid of LTA topology;

(d) a source of the titanium oxide and a compositionally consistent crystalline microporous titanosilicate solid of LTA topology; or

(e) a combination of two or more of (b)-(d), and wherein:

the OSDA comprises a 2,3-dimethyl-1-(4-methyl-benzyl)-3H-imidazol-1-ium cation of Formula (IB):

26. The composition of claim 24 , wherein the mineralizing agent comprises hydrofluoric acid (HF).

27. The composition of claim 24 , wherein the composition has:

(a) a molar ratio of the OSDA:Si is in a range of from 0.1 to 1;

(b) a molar ratio of Al:Si in a range of from 0 to 0.1, when the source of the aluminum oxide is present;

(c) a molar ratio of Ge:Si in a range of from 0 to 1, when the source of the germanium oxide is present;

(d) a molar ratio of Ti:Si in a range of from 0 to 0.1, when the source of the titanium oxide is present;

(e) a molar ratio of water:Si in a range of from about 2 to about 20; and

(f) a molar ratio of fluoride:Si in a range of from about 0.1 to about 0.75, when the mineralizing agent is HF.

28. The composition of claim 27 , wherein the aqueous composition comprises:

(b) the source of the aluminum oxide;

(c) the source of the germanium oxide;

(d) the source of the titanium oxide; or

(e) a combination of two or more of (b)-(d).

29. The composition of claim 24 , wherein the composition is a suspension or a gel.

30. The composition of claim 24 , comprising:

(b) the source of the aluminum oxide;

(c) the source of the germanium oxide;

(d) the source of the titanium oxide; or

(e) a combination of two or more of (b)-(d), and wherein

the OSDA comprises a 2,3-dialkyl-1-(4-alkyl-benzyl)-3H-imidazol-1-ium cation of Formula (IA):

wherein R 1 , R 2 , and R 7 are independently C 1-3 alkyl.