Degassing liquid eluent of a preparative SFC fluid chromatography system

Patent metadata

Field	Value
Publication number	US-10159913-B2
Application number	US-201615333876-A
Country	US
Kind code	B2
Filing date	Oct 25, 2016
Priority date	Oct 26, 2015
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

Methods, systems and apparatus are provided for degassing a supersaturated solution. An example degasser is described having a continuous body of gas-permeable tubing to remove an amount of a gas from the supersaturated solution below the gas's saturation point in the supersaturated solution. The degasser can be connected to at least one of a fraction collector or a detector. The example degasser is sized and/or positioned to cause a change in pressure (ΔP) across the degasser to drive removal of a dissolved gas from a supersaturated solution passing through the degasser. As a result of the reduction of gas, efficiencies in system flow and fraction collection are achieved.

First claim

What is claimed:

1. A degasser for removing gas from a supersaturated solution, comprising:
(i) a continuous body of gas-permeable tubing having an interior portion and an exterior portion and an inlet and an outlet for conducting the supersaturated solution through the continuous body of gas-permeable tubing; and
(ii) a fraction collector in direct fluid communication with the outlet of the continuous body of gas-permeable tubing, wherein the degasser removes a portion of the gas below the saturation point of the gas in the supersaturated solution.

2. The degasser of claim 1 , wherein a partial pressure of a component of the supersaturated solution decreases between the inlet and the outlet of the continuous body of gas-permeable tubing.

3. The degasser of claim 1 , wherein the continuous body of gas-permeable tubing is comprised of a polymeric material.

4. The degasser of claim 3 , wherein the continuous body of gas-permeable tubing is formed from a material which expands upon intake of the supersaturated solution.

5. The degasser of claim 1 , wherein a change in pressure occurs between the interior portion and exterior portion of the continuous body of gas-permeable tubing.

6. The degasser of claim 1 , wherein the gas-permeable tubing is entangled.

7. The degasser of claim 1 , further comprising a vacuum source connected to the continuous body of gas-permeable tubing.

8. A method of degassing a solution within a system, the method comprising:
(i) flowing a solution through a degasser, the degasser comprising a continuous body of tubing, having an interior portion and an exterior portion, comprised of a gas permeable material, the degasser having an inlet and an outlet;
(ii) applying a change in pressure across at least a portion of the degasser to reduce a partial pressure of a component in the solution; and
(iii) conducting the solution from the outlet of the degasser directly to an inlet of a fraction collector.

9. The method of claim 8 , wherein the partial pressure of a component in the solution will be below the supersaturation point of the solution at operative temperature and pressure conditions at or about an inlet of a detector or inlet of the fraction collector.

10. The method of claim 8 , wherein a detector or the fraction collector are at ambient pressure and temperature.

11. The method of claim 8 , wherein a change in pressure occurs between the outlet of the degasser and an inlet of a detector or the inlet of the fraction collector.

12. The method of claim 11 , wherein the pressure decreases between the outlet of the degasser and an inlet of a detector or the inlet of the fraction collector.

13. The method of claim 8 , wherein a change in temperature occurs between the outlet of the degasser and an inlet of a detector or the inlet of the fraction collector.

14. The method of claim 13 , wherein the temperature increases between the outlet of the degasser and an inlet of the of a detector or the inlet of the fraction collector.

15. A method of degassing a supersaturated solution within a mixed fluid system, comprising:
(i) providing a gas-liquid separator fluidly connected to a degasser, the degasser comprising a continuous body of tubing, having an interior portion and an exterior portion, comprised of a gas permeable material, the degasser having an inlet connected to the gas-liquid separator and an outlet;
(ii) separating at least a portion of the supersaturated solution into a gas and a first liquid eluent within the gas-liquid separator;
(iii) introducing the first liquid eluent from the gas-liquid separator into the inlet of the degasser;
(iv) applying a differential pressure gradient across the degasser;
(v) separating an additional portion of the gas from the first liquid eluent, resulting in a second liquid eluent; and
(vi) conducting the second liquid eluent from an outlet of the degasser directly to an inlet of a fraction collector.

16. The method of claim 15 , wherein the second liquid eluent comprises a greater liquid to gas ratio by weight than the first liquid eluent.

17. The degasser of claim 1 wherein the continuous body has a residence time (g) adapted to remove the portion of the gas below the saturation point of the gas in the supersaturated solution.

18. The method of claim 8 , wherein the solution introduced to the degasser is a supersaturated solution.

Assignees

• Waters Technologies Corp

Inventors

• Jackson Michael R
• Seith Christopher
• Bala Senthil
• Fredette Colin
• Sok Maruth
• Gomez Carlos
• Shreve Joshua A

Classifications

• B01D19/0031

  by filtration · CPC title

• B01D15/40 Primary

  using supercritical fluid as mobile phase or eluent · CPC title

• G01N30/84

  Preparation of the fraction to be distributed · CPC title

• G01N2030/8423

  using permeable separator tubes · CPC title