Pump-less method and apparatus for solvent extraction from a sample

Patent metadata

Field	Value
Publication number	US-2016282240-A1
Application number	US-201514671715-A
Country	US
Kind code	A1
Filing date	Mar 27, 2015
Priority date	Mar 27, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

Apparatus for extracting organic analytes from a sample comprising a first compressed gas source connected to valving and a sample extraction cell connected to the valving. A pressure regulator is connected to the extraction cell outlet to the pressure regulator. The pressure regulator blocks fluid flow when the pressure at the pressure regulator inlet is below a predetermined pressure and permits fluid flow when above said predetermined pressure. The apparatus is free of operative association with a mechanical pump or with a compressed gas source other than the compressed gas source. An extraction method for using the above apparatus is described.

First claim

What is claimed is:

1 . Apparatus for extracting organic analytes from a sample, said apparatus comprising,
(a) a compressed gas source, (b) first valving, (c) a first conduit connecting said compressed gas source with said first valving, (d) a sample extraction cell having an inlet and an outlet, (e) a second conduit connecting said first valving and said sample extraction cell inlet, said first valving having a first position blocking flow from said compressed gas source to said sample extraction cell inlet and a second position permitting fluid flow from said compressed gas source to said sample extraction cell inlet, (f) a pressure regulator having an inlet and an outlet, (g) a third conduit connecting said sample extraction cell outlet and said pressure regulator, said pressure regulator blocking fluid flow when the pressure at said pressure regulator inlet is below a predetermined pressure and permitting fluid flow when said pressure at said pressure regulator inlet is above said predetermined pressure, and (h) a heater operatively associated with said sample extraction cell, said apparatus being free of operative association with a fourth conduit for liquid solvent connected to said first valving and being free of operative association with a mechanical pump or with a compressed gas source other than said first compressed gas source.

2 . The apparatus of claim 1 in which said first valving further comprises a liquid solvent loop whereby a known volume of liquid solvent can be transported from said solvent loop to said extraction cell under pressure supplied by said compressed gas source.

3 . The apparatus of claim 1 further comprising a liquid solvent loop, having an inlet and an outlet, said solvent loop inlet being in fluid communication with the said compressed gas source and, unless blocked, with said extraction cell inlet, whereby liquid solvent at a known volume can be transported from said solvent loop to said extraction cell under pressure supplied by said compressed gas source.

4 . The apparatus of claim 1 further comprising,
(i) a collection station for collecting organic sample analytes extracted into a liquid solvent in said sample extraction cell, and
(j) a fourth conduit connecting said pressure regulator and said collection station.

5 . A method for solvent extraction of organic analytes from a sample, said method comprising,
(a) supplying a sample containing organic analytes and liquid organic solvent to a sample extraction cell having an inlet and an outlet at a first pressure less than 50 PSI, (b) starting extraction of said sample organic analytes into said organic solvent in said sample extraction cell at said first pressure, and (c) completing said extraction under conditions whereby said extraction cell is further pressurized by heating it in the absence of additional pressure supplied by a pressurized fluid flowing to said extraction cell inlet; said extraction cell being maintained under elevated temperature and pressure below supercritical conditions during said extraction completion, said method being performed without the use of a mechanical pump.

6 . The method of claim 5 further comprising,
(f) flowing a purge gas through said extraction cell after step (c).

7 . The method of claim 5 further comprising,
(d) blocking or reducing flow from said extraction cell outlet when the pressure in said cell is below a predetermined pressure or time using a pressure regulator in fluid communication with said extraction cell outlet, and
(e) flowing or increasing the flow of said organic analyte-containing organic solvent to a collection station by increasing the extraction cell pressure above said predetermined pressure to actuate said pressure regulator, all flow of said analyte-containing organic solvent in said method occurring without the use of a mechanical pump.

8 . The method of claim 7 in which said pressure regulator is a valve.

9 . The method of claim 7 in which said pressure regulator is flow restriction tubing.

10 . The method of claim 7 in which the pressure in step (c) does not exceed about 100 PSI.

Assignees

• Dionex Corp

Inventors

• Srinivasan Kannan
• Ullah Sm Rahmat

Classifications

• B01D11/0203 Primary

  with a supercritical fluid · CPC title

• B01L3/567

  Valves, taps or stop-cocks · CPC title

• B01L2400/06

  Valves, specific forms thereof · CPC title

• B01D11/0207

  Control systems · CPC title

• G01N1/34 Primary

  Purifying; Cleaning {(processes or apparatus for extracting or separating nucleic acids from biological samples C12N15/1003)} · CPC title