Systems and methods for separating gases
The invention pertains to processes for separating water from air. The processes may employ using an LCST solution with or without subsequent reverse osmosis, nanofiltration, or ultrafiltration.
1. A process comprising:
absorbing water vapor in a liquid system comprising one or more physical solvents, wherein said one or more physical solvents comprise one or more liquid phases in the liquid system; and
increasing the number of liquid phases in said liquid system by changing one or more system conditions wherein the temperature of said liquid system is greater than −30° C. and less than 500° C. during the changing and wherein at least one liquid phase in said liquid system comprises absorbed water vapor; and
separating the at least one liquid phase comprising absorbed water vapor from said liquid system; and wherein the changing one or more system conditions comprises increasing the temperature of the liquid system above a LCST.
2. The process of claim 1 wherein the one or more liquid solvents is non-aqueous.
3. The process of claim 1 wherein the one or more liquid solvents comprises an organic solvent.
4. The process of claim 1 further comprising separating water from the at least one liquid phase comprising absorbed water vapor.
5. The process of claim 1 wherein the increasing the number of liquid phases in said liquid system comprises increasing the number of liquid phases from one liquid phase to two or more liquid phases.
6. The process of claim 1 which further comprises a separation step prior to said absorbing step.
7. The process of claim 1 wherein said changing the number of liquid phases in said liquid system results in one or more of the following: (1) change in the solubility of one or more gases; (2) change in the partial pressure of one or more gases; (3) change in the partial pressure of one or more gases to facilitate the desorption of one or more gases; (4) change in the partial pressure of one or more gases to facilitate the absorption of one or more gases; (5) release heat; (6) absorb heat; (7) change the solubility of one or more gases relative to the solubility of one or more other gases; or (8) a combination thereof.
8. The process of claim 1 wherein two or more steps occur simultaneously.
9. The process of claim 1 wherein the temperature of said liquid system is greater than −10° C. and less than 200° C. during the changing.
10. The process of claim 1 wherein the temperature of said liquid system is greater than 0° C. and less than 100° C. during the changing.
11. The process of claim 1 wherein the temperature of said liquid system is greater than 5° C. and less than 95° C. during the changing.
12. The process of claim 1 wherein the temperature of said liquid system is greater than 5° C. and less than 40° C. during the changing.
13. The process of claim 1 wherein the changing one or more system conditions further comprises changing the pressure of the system.
14. The process of claim 1 wherein the changing one or more system conditions further comprises adding a reagent.