Zirconium metal-organic framework and a method of capturing carbon dioxide
A zirconium metal-organic framework, which is a coordination product formed between zirconium ion clusters and a linker that links together adjacent zirconium ion clusters, wherein the linker is of formula (I) wherein R 1 is hydrogen or an optionally substituted alkyl, and R 2 to R 4 are independently hydrogen, an optionally substituted alkyl, an optionally substituted aryl, or an optionally substituted arylalkyl. A method of capturing CO 2 from a gas mixture with the zirconium metal-organic framework.
1. A zirconium metal-organic framework, which is a coordination product formed between:
zirconium ion clusters; and
a linker that links together adjacent zirconium ion clusters;
wherein the linker is of formula (I)
wherein:
R 1 is hydrogen or an optionally substituted alkyl, and
R 2 to R 4 are independently hydrogen, an optionally substituted alkyl, an optionally substituted aryl, or an optionally substituted arylalkyl.
2. The zirconium metal-organic framework of claim 1 , wherein R 1 is hydrogen.
3. The zirconium metal-organic framework of claim 1 , wherein R 2 to R 4 are each hydrogen.
4. The zirconium metal-organic framework of claim 1 , wherein the linker is
5. The zirconium metal-organic framework of claim 1 , which has a zirconium ion to linker molecular ratio of 0.5:1 to 2:1.
6. The zirconium metal-organic framework of claim 1 , wherein the zirconium ion clusters are of formula [Zr 6 O 4 (OH) 4 ] 12+ .
7. The zirconium metal-organic framework of claim 1 , which is isoreticular with metal-organic framework UiO-66.
8. The zirconium metal-organic framework of claim 1 , which has a BET surface area of 300 to 600 m 2 /g.
9. The zirconium metal-organic framework of claim 1 , which has a pore volume of 0.1 to 0.25 cm 3 /g.
10. The zirconium metal-organic framework of claim 1 , which has a CO 2 uptake capacity of 75 to 90 cm 3 /g at 273 K, 40 to 60 cm 3 /g at 298 K, and 20 to 35 cm 3 /g at 313 K, each at 760 Torr.
11. The zirconium metal-organic framework of claim 1 , which has an ideal selectivity of CO 2 /N 2 of 55 to 75, and an ideal selectivity of CO 2 /CH 4 of 10 to 22.
12. A method of making the zirconium metal-organic framework of claim 1 , the method comprising:
mixing a zirconium(IV) salt and the linker of formula (I) in a polar aprotic solvent to form a complexation mixture; and
heating the complexation mixture at 100 to 150° C. for 12 to 72 hours.
13. The method of claim 12 , wherein a concentration of the zirconium(IV) salt in the complexation mixture is 0.01 to 0.03 M and a concentration of the linker of formula (I) in the complexation mixture is 0.005 to 0.025 M.
14. The method of claim 12 , wherein the zirconium(IV) salt is ZrCl 4 and the polar aprotic solvent is dimethylformamide.
15. A method of capturing CO 2 from a gas mixture, the method comprising:
contacting the gas mixture with the zirconium metal-organic framework of claim 1 to adsorb at least a portion of the CO 2 into the zirconium metal-organic framework, thereby forming a loaded zirconium metal-organic framework and a gas stream depleted in CO 2 compared to the gas mixture.
16. The method of claim 15 , wherein the gas mixture further comprises at least one other gas selected from the group consisting of hydrogen, oxygen, nitrogen, methane, and carbon monoxide.
17. The method of claim 15 , wherein the gas mixture is a pre-combustion gas mixture comprising 15 to 50 vol. % of CO 2 , based on a total volume of the gas mixture.
18. The method of claim 15 , wherein the gas mixture is a post-combustion gas mixture comprising 5 to 15 vol. % of CO 2 , based on a total volume of the gas mixture.
19. The method of claim 15 , wherein the gas mixture has a temperature of −5 to 50° C.
20. The method of claim 15 , wherein the gas stream depleted in CO 2 contains at least 25% less CO 2 by volume compared to a volume of CO 2 present in the gas mixture.