Conversion of nitrogen dioxide (NO
View Patent ↗Various systems, devices, NO 2 absorbents, NO 2 scavengers and NO 2 recuperator for generating nitric oxide are disclosed herein. According to one embodiment, an apparatus for converting nitrogen dioxide to nitric oxide can include a receptacle including an inlet, an outlet, a surface-active material coated with an aqueous solution of ascorbic acid and an absorbent wherein the inlet is configured to receive a gas flow and fluidly communicate the gas flow to the outlet through the surface-active material and the absorbent such that nitrogen dioxide in the gas flow is converted to nitric oxide.
1. An apparatus for converting nitrogen dioxide to nitric oxide comprising
a receptacle including an inlet, an outlet, a surface-active material coated with an aqueous solution of ascorbic acid and an absorbent,
wherein the inlet is configured to receive a gas flow and fluidly communicate the gas flow to the outlet through the surface-active material and the absorbent such that nitrogen dioxide in the gas flow is converted to nitric oxide;
wherein the apparatus further comprises a NO 2 scavenger selected from the group consisting of proline and diphenylamine.
2. The apparatus of claim 1 , wherein the absorbent is silica gel.
3. The apparatus of claim 1 , wherein the absorbent is activated alumina.
4. A recuperator for converting nitrogen dioxide into nitric oxide comprising: an exit shell including an outlet; an inside shell wherein the inside shell includes perforated inner and outer tubes with fixed annulus; a surface-active material coated with an aqueous solution of ascorbic acid and an adsorbent; a top cap including an inlet wherein the inlet is configured to receive a gas flow and fluidly communicate the gas flow to the outlet through the surface-active material such that nitrogen dioxide in the gas flow is converted to nitric oxide; and a NO 2 scavenger selected from the group consisting of proline and diphenylamine.
5. The recuperator of claim 4 , further comprising an annular ring around the top cap.
6. The recuperator of claim 4 , wherein the recuperator has a flow resistance of less than 3 cm of water pressure at a flow of 60 L/minute.
7. The recuperator of claim 4 , wherein the recuperator has a flow resistance of less than 1 cm water at 15 L/min.
8. The recuperator of claim 4 , wherein the recuperator is operated at atmospheric pressure.
9. The recuperator of claim 4 , wherein the recuperator has an oxygen concentration of in the range of 21 to 100%.
10. The recuperator of claim 4 , wherein the recuperator has a humidity of dry to 99% (non condensing).
11. The recuperator of claim 4 , wherein the recuperator is thermally insulated.
12. The recuperator of claim 4 , wherein the recuperator is coupled to the outlet of a first device through a humidified line.
13. The recuperator of claim 12 , wherein the humidified line is heated.
14. The recuperator of claim 13 , wherein the humidified line is heated to about 35° C.
15. The recuperator of claim 4 , wherein the recuperator is coupled to a NO/NO 2 gas analyzer.
16. The recuperator of claim 4 , wherein the recuperator further comprises a particle filter.