Synthesis of mordenite using multiple organics
The methods for synthesizing mordenite (MOR) zeolite crystals described herein utilize a combination of organics and produce MOR crystals with reduced size, higher Si/Al ratio, fewer stacking faults, less occluded organics in the final product, and a longer catalyst lifetime.
1. A method for forming a mordenite (MOR) material, comprising:
combining N, N-trimethyl-1-1-adamantammonium (TMAda), at least one alcohol, a sodium source, an aluminum source, and a silica source at room temperature to form a synthesis mixture, wherein the N, N-trimethyl-1-1-adamantammonium (TMAda) and the at least one alcohol are combined to produce a synthesis mixture comprising an excess of the alcohol relative to the N, N-trimethyl-1-1-adamantammonium (TMAda);
maintaining the synthesis mixture for a time and at a temperature sufficient to allow mordenite (MOR) material to form; and
separating the mordenite (MOR) material from the synthesis mixture.
2. The method of claim 1 , wherein the at least one alcohol is 1,2-hexanediol (D6 1,2 ).
3. The method of claim 1 , wherein the N, N-trimethyl-1-1-adamantammonium (TMAda) and the at least one alcohol are combined at a ratio of about 1.5 to 16.0 of the alcohol to the N, N-trimethyl-1-1-adamantammonium (TMAda) in the synthesis mixture.
4. The method of claim 1 wherein the sodium source is sodium hydroxide, the aluminum source is aluminum hydroxide, and the silica source is fumed silica.
5. The method of claim 1 wherein the mordenite (MOR) material is mordenite (MOR) nanosheets.
6. The method of claim 5 , wherein the mordenite (MOR) nanosheets have an average thickness of 60-80 nm.
7. The method of claim 1 , further comprising the step of washing the mordenite (MOR) material with a solvent after separation from the synthesis mixture.
8. The method of claim 7 , wherein the solvent is water.
9. The method of claim 1 , wherein crystals in the mordenite (MOR) material have dimensions of less than 100 nm.
10. The method of claim 1 , wherein the mordenite (MOR) material has a Si/Al ratio of about 10.
11. The method of claim 1 , further comprising one or more of the steps of heating, stirring, rotating under pressure, or centrifuging the synthesis mixture in order to allow the mordenite (MOR) material to form or to separate the mordenite (MOR) material from the synthesis mixture.
12. The method of claim 1 , wherein the at least one alcohol is 1,2-hexanediol (D6 1,2 ), the sodium source is sodium hydroxide, the aluminum source is aluminum hydroxide, and the silica source is fumed silica, and wherein the synthesis mixture has a molar composition of Al(OH) 3 :1.0 SiO 2 :0.2 NaOH:44 H 2 O:0.1 TMAda-OH:1.6 1,2-hexanediol.