Cold trap enhanced input into low-cost analyzer

Patent metadata

Field	Value
Publication number	US-11709149-B2
Application number	US-202217939676-A
Country	US
Kind code	B2
Filing date	Sep 7, 2022
Priority date	Sep 10, 2021
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

Examples are directed toward systems and methods relating to collecting and analyzing samples. For example, a system includes a cold trap that directly collects a sample. The cold trap operates to serve as a collection filter while the system draws in a flow across the cold trap. A thermal heater, coupled to the cold trap, flash heats the cold trap to produce a released sample from the cold trap at a release concentration. An analyzer entrains the released sample at the release concentration into a sampling flow of the analyzer for analysis.

First claim

What is claimed is:

1. A system comprising:
a thermal desorber that receives a high-volume sampler concentrating filter transferred from a vapor sampler and loaded into the system, and heats the high-volume sampler concentrating filter to cause the high-volume sampler concentrating filter to release a sample collected by the high-volume sampler concentrating filter;
a cold trap that collects the sample while the system draws in a flow from the thermal desorber across the cold trap;
a thermal heater, coupled to the cold trap, that flash heats the cold trap to produce a released sample from the cold trap at a release concentration; and
an analyzer that entrains the released sample at the release concentration into a sampling flow of the analyzer for analysis.

2. The system of claim 1 , further comprising a focusing trap that entrains the sample onto the cold trap.

3. The system of claim 2 , wherein the focusing trap is a fluid flow-designed funnel.

4. The system of claim 1 , wherein the cold trap is a volumetric cold trap.

5. The system of claim 1 , wherein the cold trap includes a sorbent.

6. The system of claim 5 , wherein the sorbent includes at least one of steel wire, polymers, porous polymer resins, graphite, and glass beads.

7. The system of claim 1 , wherein the cold trap is coupled to the analyzer via a coupling material.

8. The system of claim 7 , wherein the coupling material is heated to facilitate transfer of sample into the analyzer.

9. The system of claim 7 , wherein the coupling material is passivated to facilitate transfer of sample into the analyzer.

10. The system of claim 7 , wherein the coupling material is chemically inert to facilitate transfer of sample into the analyzer.

11. The system of claim 1 , wherein the cold trap is coupled to the analyzer via an ionization source of the analyzer which leads into a drift tube of the analyzer.

12. The system of claim 1 , wherein the analyzer is an ion mobility spectrometer (IMS).

13. The system of claim 1 , wherein the analyzer is a mass spectrometer (MS) that is not triple quadrupole.

14. A system comprising:
a thermal desorber to heat a high-volume sampler concentrating filter transferred from a vapor sampler to the thermal desorber, the thermal desorber being configured to receive the high-volume sampler concentrating filter loaded into the system, and cause the high-volume sampler concentrating filter to release a sample collected by the high-volume sampler concentrating filter;
a valve to controllably release the sample from the thermal desorber into a sampling flow;
a cold trap that directly collects the sample from the sampling flow;
a thermal heater, coupled to the cold trap, that flash heats the cold trap for a flash time duration to produce a released sample from the cold trap at a release concentration;
an analyzer that entrains the released sample at the release concentration from the sampling flow of the analyzer for analysis; and
a controller that directs operation of the thermal desorber, the valve, the cold trap, the thermal heater, and the analyzer.

15. The system of claim 14 , wherein the controller directs the thermal desorber to ramp a temperature of the filter from 100 degrees F. to 600 degrees F.

16. The system of claim 14 , wherein the controller sets the cold trap to a temperature of between −25 degrees F. and 40 degrees F.

17. The system of claim 14 , wherein the thermal desorber includes a resistive heater.

18. The system of claim 14 , wherein the controller adjusts the thermal desorber to apply heat to the filter according to a ramped temperature raise.

19. The system of claim 14 , wherein the controller adjusts the thermal desorber to flash heat the filter.

20. The system of claim 14 , wherein the controller adjusts the thermal heater to apply heat to the cold trap according to a ramped temperature raise.

21. The system of claim 20 , wherein the controller adjusts the thermal heater according to the ramped temperature raise including at least one hold time at a temperature corresponding to at least one volatile compound.

22. The system of claim 14 , wherein the valve is a shuttle gate to the cold trap, which flushes into the analyzer.

23. The system of claim 14 , further comprising a system heater and cooler, to adjust temperatures of system components including the thermal desorber, the valve, the cold trap, and the analyzer.

24. A method comprising:
loading a high-volume sampler concentrating filter from a vapor sampler into a thermal desorber;
heating, using the thermal desorber, the high-volume sampler concentrating filter to cause the high-volume sampler concentrating filter to release a sample collected by the high-volume sampler concentrating filter;
operating a cold trap for a sample time duration to obtain the sample released from the high-volume sampler concentrating filter;
flash heating the cold trap to release the sample at a release concentration; and
entraining the sample, released from the cold trap at the release concentration, into a sampling flow of an analyzer.

25. The method of claim 24 , further comprising adjusting the flash heating of the cold trap according to a ramped temperature raise including at least one hold time at a temperature corresponding to at least one volatile to be sampled.

26. A method comprising:
collecting a sample on a high-volume sampler concentrating filter of a high-volume air sampler;
transferring the high-volume sampler concentrating filter from the high-volume air sampler to a thermal desorber;
heating the filter for a desorbing duration using the thermal desorber, to controllably release, into a sampling flow, the sample collected by the filter;
collecting the sample from the sampling flow by operating a cold trap for a sample time duration;
flash heating the cold trap to produce a released sample at a release concentration; and
entraining the sample, released from the cold trap at the release concentration, into the sampling flow of an analyzer.

27. The method of claim 26 , further comprising heating, to temperatures above ambient, detection system components including the thermal desorber, a valve coupling output of the thermal desorber to the cold trap, the analyzer, and a drift tube of the analyzer, to prevent system cold spots and increase transfer of the sample.

28. The method of claim 27 , further comprising heating the detection system components to 180 degrees F. or above.

29. The method of claim 27 , further comprising heating the detection system components to 600 degrees F. to remove background signatures.

30. The method of claim 26 , further comprising maintaining the sampling flow at 250 mL/min.

Assignees

• The Government Of The Us Secretary Of Homeland Security

Inventors

• Smith Barry T
• Brady John
• Barber Jeffrey

Classifications

• G01N27/623 Primary

  combined with mass spectrometry · CPC title

• H01J49/0031

  Step by step routines describing the use of the apparatus (H01J49/0081 takes precedence) · CPC title

• G01N1/4022 Primary

  by thermal techniques; Phase changes · CPC title

• H01J49/26

  Mass spectrometers or separator tubes · CPC title

• G01N2001/4033

  sample concentrated on a cold spot, e.g. condensation or distillation · CPC title