SYSTEMS AND METHODS FOR CARBON DIOXIDE CAPTURE
There is provided a structurally stable monolith substrate, suitable to provide carbon dioxide capture structure for removing carbon dioxide from air, having two major opposed surfaces, and further having a plurality of longitudinal channels extending between and opening through the two major opposed surfaces of the structurally stable monolith substrate; and a macroporous coating, adhered to the interior wall surfaces of the longitudinal channels, comprising an adherent, coating formed of cohered, compact mesoporous particles each being formed of a material that is compatible with the material forming the underlying substrate structure so as to become adherent thereto when coated. The mesoporous particles are capable of supporting in their mesopores a sorbent for CO 2 There is also provided a method for forming the monolith and a system for utilizing the monolith as part of a CO 2 capture structure, within the system, to remove CO 2 from the atmosphere.
1 - 20 . (canceled)
21 . A method for removing CO 2 from a gas stream, the method comprising:
contacting a gas stream with a honeycomb monolith containing a CO 2 sorbent;
wherein the honeycomb monolith is comprised of longitudinal channels connecting two opposed surfaces of the monolith;
wherein the longitudinal channels comprise macropore and mesopore containing walls;
wherein the CO 2 sorbent occupies a fraction of a mesopore volume within the macropore and mesopore containing walls;
removing CO 2 from the gas stream by sorbing CO 2 using the CO 2 sorbent as the gas stream flows through the longitudinal channels; and
removing the sorbed CO 2 from the CO 2 sorbent by heating the honeycomb monolith to about 60° C. to 130° C.;
wherein an amount of time taken for removing the CO 2 from the gas stream is about 3 to 10 times an amount of time taken for removing the sorbed CO 2 .
22 . The method of claim 21 , wherein the honeycomb monolith has a channel opening density of about 50 channels per square inch to 400 channels per square inch;
wherein the open face area (OFA) of the opposed surfaces is about 0.5 to 0.9; and
wherein a length of the honeycomb monolith is about 3 inches to 24 inches.
23 . The method of claim 21 , wherein the macropore and mesopore containing walls comprise mesopores and macropores;
wherein a macropore diameter is about 0.15 microns to 2 microns;
wherein a mesopore diameter is about 10 nm 50 nm;
wherein a mesopore volume is about 0.4 cc/g to 1.5 cc/g; and
wherein a ratio of macropores to mesopores is about 1:5 to about 2:1.
24 . The method of claim 23 , wherein the macropore and mesopore containing walls comprises sintered mesoporous particles having macropores separating the mesoporous particles, wherein the sorbent comprises an amine.
25 . The method of claim 23 , wherein the longitudinal channels comprise a solid macro-mesoporous coating that forms the macropore and mesopore containing walls.
26 . The method of claim 25 , wherein the macropore and mesopore containing walls is comprised of an inorganic oxide or a porous mineral/ceramic.
27 . The method of claim 26 , wherein the mesopores are physically impregnated with or chemically bonded to a sorbent comprising an amine.
28 . The method of claim 25 , wherein the amine is an aminopolymer, and wherein the aminopolymer is branched, hyperbranched, dendritic, or linear.
29 . The method of claim 21 , wherein the fraction is about 40% to 100%.
30 . The method of claim 21 , wherein the heating occurs by contacting the honeycomb monolith with steam.
31 . The method of claim 31 , wherein the gas stream has an approach velocity of about 2 m/s to 10 m/s.
32 . The method of claim 31 , wherein the gas stream comprises a CO 2 concentration of about 10% or less, and wherein the gas is selected from ambient air, flue gas, or a combination thereof.
33 . The method of claim 31 , wherein the amount of time taken for removing the CO 2 from the gas stream is about 3 times the amount of time taken for removing the sorbed CO 2 , about 9 times the amount of time taken for removing the sorbed CO 2 , or about 10 times the amount of time taken for removing the sorbed CO 2 .
34 . A system for removing CO 2 from a gas stream, the system comprising:
a loop of capture structures, each capture structure comprised of a honeycomb monolith, wherein the honeycomb monolith contains a CO 2 sorbent; and
wherein the number of capture structures is equal to a ratio, wherein the ratio is an amount of time taken for removing the CO 2 from the gas stream and an amount of time taken for removing the sorbed CO 2 .
35 . The system of claim 34 , wherein the gas stream comprises a CO 2 concentration of about 10% or less, and wherein the gas is selected from ambient air, flue gas, or a combination thereof.
36 . The system of claim 34 , wherein the honeycomb monolith is comprised of longitudinal channels connecting two opposed surfaces of the monolith;
wherein the channels comprise macropore and mesopore containing walls; and
wherein the CO 2 sorbent occupies about 40% to 100% of a mesopore volume within the macropore and mesopore containing walls.
37 . The system of claim 34 , wherein the honeycomb monolith has a channel opening density of about 50 channels per square inch to 400 channels per square inch; wherein the open face area (OFA) of the opposed surfaces is about 0.5 to 0.9; and wherein a length of the honeycomb monolith is about 3 inches to 24 inches.
38 . The system of claim 36 , wherein the macropore and mesopore containing walls comprise mesopores and macropores; wherein a macropore diameter is about 0.15 microns to 2 microns; wherein a mesopore diameter is about 10 nm 50 nm; wherein a mesopore volume is about 0.4 cc/g to 1.5 cc/g; wherein a ratio of macropores to mesopores is about 1:5 to about 2:1.
39 . The system of claim 36 , wherein the macropore and mesopore containing walls comprises sintered mesoporous particles having macropores separating the mesoporous particles, wherein the sorbent comprises an amine.
40 . The system of claim 33 , wherein the macropore and mesopore containing walls is comprised of an inorganic oxide or a porous mineral/ceramic; and wherein the mesopores are physically impregnated with or chemically bonded to a sorbent comprising an amine.