Monolithic natural gas storage delivery system based on sorbents
The invention provides methods for producing a strong, light, sorbent-based storage/dispenser system for gases and fuels. The system comprises a porous monolithic material with an adherent strong impervious skin that is capable of storing a gas under pressure in a safe and usable manner.
1. A gas storage and delivery device comprising a porous gas sorbent monolith contained within an adherent skin, wherein:
the skin is impervious to the gas at >35 atm and comprises a port capable of providing a fluid connection between the monolith and a gas charge/discharge manifold; and
the monolith comprises properties:
(a) a surface area of >100 m 2 /g;
(b) a density of ≧0.5 g/cc;
(c) interconnected pores with some hierarchical structure and of typical diameter larger than 0.5 and smaller than 1.5 nm;
(d) tensile modulus >2 Mpsi, tensile strength >1 kpsi and flexural strength >2 kpsi; and
(e) chemical stability in that it does not degrade, or is not significantly attacked by species present, in a gas that is natural gas, hydrogen or CO 2 .
2. The device of claim 1 wherein the monolith comprises a material that is mostly one or more light elements selected from C, B, Si, Mg, Al and Ti.
3. The device of claim 1 wherein the monolith is made of carbon and the surface area is over 1000 m 2 /g.
4. The device of claim 1 wherein the monolith is made of carbon that is a pyrolysis product of a natural product, or a polymeric precursor.
5. The device of claim 1 wherein the skin comprises a material selected from a polymer, metal and carbon.
6. The device of claim 1 , wherein the skin comprises a material selected from metals, metal alloys, or any graded or layered composite thereof.
7. The device of claim 1 , wherein the skin is less than 5 mm thick.
8. The device of claim 1 wherein where the skin is reinforced by a second layer of gas tank material.
9. The device of claim 1 wherein the device comprises the manifold in the form of a tube with a valve that sustains at least 35 bar of pressure.
10. The device of claim 1 wherein the device comprises the manifold in the form of a tube with a flange, and a ring of a metal around the port configured so that the ring and flange can be mated so that manifold is gas tight to pressures over 35 bar.
11. The device of claim 1 further comprising a circulating conductive fluid that bathes the monolith and is contained by an external casing, which provides heat transfer during charging and discharging the gas.
12. The device of claim 1 comprising resistance heaters which provide heating during gas discharge and heat pipes in the monolith which provide cooling.
13. The device of claim 1 comprising the gas at >35 atm.
14. A gas storage and delivery device comprising a microporous or nanoporous, gas sorbent monolith contained within an adherent skin, wherein:
the skin is impervious to the gas at >35 atm, and comprises one or more ports, each capable of providing a fluid connection between the monolith and a gas charge/discharge manifold; and
the monolith comprises microporous or nanoporous carbon.
15. The device of claim 14 wherein the microporous carbon comprises properties:
Bulk Density 1.12 g/cm 3 ;
Heat Capacity 0.9-1.2 cal/g.K;
Coefficient of Thermal Expansion 3.2×10 −6 /K;
Ash Content (ASTM D2866-94) <0.1%;
Thermal Conductivity 1.2 W/mK;
Pore Size Distribution 0.5-0.8 nm w/0.02 nm precision;
BET-N2 Surface Area 1026 m 2 /g; and
Micropore Volume (fraction) 0.41 cm 3 /g (45%).
16. A method of using the device of claim 1 for storing and delivering a gas comprising:
introducing the gas into the device under pressure >35 atm.
17. A method of making the device of claim 1 comprising the step of forming the skin on the monolith by coating.
18. The gas storage and delivery device of claim 1 wherein the monolith comprises material encased in a macroscopic sponge wherein:
a) the material is a high surface area carbon or a carbon precursor and the sponge is a SiC sponge; or
b) the material is a high surface area carbon or a carbon precursor or zeolite or MOF and the sponge is a foam of Al or Ti metal.
19. A gas storage and delivery device of claim 1 wherein:
a) the monolith comprises a composite or several blocks joined together; and/or,
b) the skin provides a tank of several blocks joined together to form larger tanks capable of forming a variety of shapes that can be conforming to and fill selected spaces.
20. A gas storage and delivery device of claim 1 further comprising multiple components distributed in smaller units interconnected wherein several impermeable block units are joined together by compatible pipes in distributed geometry that matches available spaces in the system.