Method of producing an aromatization catalyst
According to the subject matter of the present disclosure, a method of producing an aromatization catalyst may comprise producing a plurality of uncalcined ZSM-5 nanoparticles via a dry-gel method, directly mixing the plurality of uncalcined ZSM-5 nanoparticles with large pore alumina and a binder to form a ZSM-5/alumina mixture, and calcining the ZSM-5/alumina mixture to form the aromatization catalyst. The plurality of uncalcined ZSM-5 nanoparticles may have an average diameter of less than 80 nm.
1. A method of producing an aromatization catalyst, the method comprising:
producing a plurality of uncalcined ZSM-5 nanoparticles via a dry-gel method, wherein the plurality of ZSM-5 nanoparticles has an average diameter of less than 80 nm;
directly mixing the plurality of uncalcined ZSM-5 nanoparticles with large pore alumina and a binder to form a ZSM-5/alumina mixture; and
calcining the ZSM-5/alumina mixture to form the aromatization catalyst; wherein the large pore alumina has a pore size of from 18 nm to 26 nm.
2. The method of producing an aromatization catalyst of claim 1 , wherein the plurality of uncalcined ZSM-5 nanoparticles has not been subjected to centrifugation above 3,000 rpm, before being mixed with the large pore alumina and binder.
3. The method of producing an aromatization catalyst of claim 1 , wherein the plurality of uncalcined ZSM-5 nanoparticles has not been subjected to calcination above 200° C. for more than 30 minutes, before being mixed with the large pore alumina and binder.
4. The method of producing an aromatization catalyst of claim 1 , wherein the ZSM-5/alumina mixture is calcined at a temperature of from 400° C. to 700° C. for from 1 hour to 10 hours.
5. The method of producing an aromatization catalyst of claim 1 , wherein the aromatization catalyst is impregnated with gallium atoms to form a Ga-ZSM-5 catalyst.
6. The method of producing an aromatization catalyst of claim 5 , wherein the Ga-ZSM-5 catalyst is calcined.
7. The method of producing an aromatization catalyst of claim 1 , wherein the aromatization catalyst is impregnated with a catalytic metal to form a metal-ZSM-5 catalyst, the metal-ZSM-5 catalyst comprises from 50 wt. % to 90 wt. % ZSM-5, 5 wt. % to 30 wt. % large pore alumina, 10 wt. % to 20 wt. % binder, and 0.2 wt. % to 6 wt. % catalytic metal.
8. The method of producing an aromatization catalyst of claim 7 , wherein the catalytic metal comprises gallium.
9. The method of producing a catalyst of claim 1 , wherein the directly mixing is extrusion.
10. The method of producing an aromatization catalyst of claim 1 , wherein the plurality of uncalcined ZSM-5 nanoparticles has an average diameter 30 nm to 80 nm.
11. The method of producing an aromatization catalyst of claim 1 , wherein at least 90% of the individual uncalcined ZSM-5 nanoparticles have diameters from 20 nm to 50 nm.
12. The method of producing an aromatization catalyst of claim 1 , wherein an average pore size of the uncalcined ZSM-5 nanoparticles is from 35 nm to 55 nm.
13. The method of producing an aromatization catalyst of claim 1 , wherein a BET surface area of the uncalcined ZSM-5 nanoparticles is from 300 m 2 /g to 600 m 2 /g.
14. The method of producing an aromatization catalyst of claim 1 , wherein a pore volume of the uncalcined ZSM-5 nanoparticles is from 0.3 ml/g to 0.45 ml/g.
15. The method of producing a catalyst of claim 1 , wherein the producing the plurality of uncalcined ZSM-5 nanoparticles via the dry-gel method comprises:
combining an alumina source, a structure directing agent, and a silica source to form a slurry;
optionally, introducing NaOH to the slurry such that the final concentration of NaOH in the slurry is from 0.000001 g/L to 0.1 g/L;
drying the slurry to form a dry-gel; and
autoclaving the dry-gel in a humidified autoclave to form the plurality of uncalcined ZSM-5 nanoparticles.
16. The method of producing an aromatization catalyst of claim 15 , wherein the water content of the dry-gel is less than 25 wt. %.
17. The method of producing an aromatization catalyst of claim 15 , wherein the dry-gel is not agitated during autoclaving.