Metal-organic frameworks for oxygen storage and air separation
Adsorption systems providing a capacity of at least 200 g/L for oxygen-containing mixtures, or an oxygen-nitrogen selectivity of at least 1.4:1 or at least 1:2 with an adsorbed capacity of at least 0.6 mmol/g at 4 bar and 22° C.
1. A method of using a metal-organic framework (MOF) comprising a coordination product of at least one metal ion and at least one multidentate organic ligand, comprising:
loading an adsorption vessel with MOF;
charging the MOF with oxygen gas or oxygen-containing gaseous mixtures; and
storing the oxygen gas or oxygen-containing gaseous mixtures in the MOF,
wherein the MOF provides an oxygen capacity of at least 200 g/L at 140 bar and 22° C.
2. The method of claim 1 , wherein the MOF exhibits a gravimetric surface area between 600 and 14,500 m 2 /g, a pore volume between 1 and 3 cc/g and an average micropore size between 2 Å and 25 Å.
3. The method of claim 1 , wherein the MOF comprises a gravimetric surface area between 600 and 7,000 m 2 /g, a pore volume between 0.44 and 4.4 cc/g and an average micropore size between 5 Å and 25 Å.
4. The method of claim 1 , wherein the capacity of oxygen at 2,000 psi and 22° C. is between 200 and 650 g/L.
5. The method of claim 1 , wherein the capacity of oxygen at 2,000 psi and 22° C. is between 200 and 375 g/L.
6. The method of claim 1 , wherein the MOF is mechanically formed into a shape having a diameter between 0.1 and 10 mm.
7. A method of using a metal-organic framework (MOF) comprising coordination product of at least one metal ion and at least one multidentate organic ligand, comprising: loading an adsorption vessel with MOF, charging said vessel with a mixed-component air stream at high pressure and discharging the air stream from said vessel at a lower pressure, wherein the MOF provides an oxygen-nitrogen selectivity of at least 1.4:1 or at least 1:2 at 4 bar at 22° C.
8. The method of claim 7 , wherein the metal ion is selected from Co 2+ , Fe 2+ , Ni 2+ , Cu 2+ , Zr 4+ , Mn 3+ , Mg 2+ , and combinations thereof.
9. The method of claim 7 , wherein the MOF exhibits a gravimetric surface area between 600 and 14,500 m 2 /g, a pore volume between 1 and 3 cc/g, and an average micropore size between 2 Å and 25 Å.
10. The method of claim 7 , wherein the MOF comprises a gravimetric surface area between 600 and 7,000 m 2 /g, a pore volume between 0.44 and 4.4 cc/g, and an average micropore size between 5 Å and 25 Å.
11. The method of claim 7 , wherein the MOF contains charged anions and cations distributed throughout the MOF.
12. The method of claim 7 , wherein the MOF is formed into a shape through the use of a binder or embedded into a macroporous scaffold, having a macropore distribution of 500 Å to 10,000 Å.
13. The method of claim 7 , wherein the oxygen recovery is greater than 30% at 90% purity.
14. The method of claim 7 , wherein the oxygen recovery is greater than 40% at 90% purity.
15. The method of claim 7 , wherein the target oxygen flow rate is 0.10-10,000 SLPM and the target oxygen purity is 88-95%.
16. The method of claim 7 , where the feed is pressurized to 15-60 psig.
17. The method of claim 7 , where the desired product gas is nitrogen.
18. The method of claim 7 , wherein the desired product gas is argon.
19. The method of claim 18 , wherein the method comprises a first stage comprising adsorbing one of nitrogen or oxygen in a first MOF in a first vessel followed by second stage of adsorbing the other of nitrogen or oxygen in a second MOF in a second vessel.
20. The method of claim 7 , further comprising storing the air stream in the MOF.