Process and system for rapid sample analysis
Components resolved in time by a separator accumulate in a sample cell and are analyzed by electromagnetic radiation-based spectroscopic techniques. The sample cell can be configured for multiple path absorption and can be heated. The separator can be a gas chromatograph or another suitable device, for example a distillation-based separator. The method and system described herein can include other mechanical elements, controls, procedures for handling background and sample data, protocols for species identification and/or quantification, automation, computer interfaces, algorithms, software or other features.
1. A sample analysis system, comprising:
a gas chromatography system from which components of a sample elute over time;
a sample cell, which has been partially or fully evacuated, in which the components are collected;
a Fourier transform infrared spectrometry system for obtaining current infrared spectra of the components in the sample cell; and
a computer system that receives the current infrared spectra detected by the Fourier transform infrared spectrometry system and maintains background infrared spectra that include infrared spectra from previously eluted components and analyzes currently eluting components with reference to the background infrared spectra.
2. A system as claimed in claim 1 , wherein the Fourier transform infrared spectrometry system measures absorption spectra.
3. A system as claimed in claim 1 , wherein a path length in the sample cell is increased by a multiple path optical arrangement.
4. A system as claimed in claim 1 , wherein the sample cell includes a White cell or modified White cell type optical arrangement.
5. A system as claimed in claim 1 , further comprising a vacuum device for fully evacuating or partially evacuating the sample cell.
6. A system as claimed in claim 1 , further comprising a valve for isolating the sample cell from a pumping device, a valve for diverting output from the separator away from the sample cell, a sample cell pressure control, or any combination thereof.
7. A system as claimed in claim 1 , further comprising a sample concentrating device for collecting the sample before the gas chromatography system.
8. A system as claimed in claim 7 , wherein the sample concentrating device is a TDT, purge and trap or a solvent concentrating device.
9. A system as claimed in claim 1 , further comprising automated instrument controls.
10. A system as claimed in claim 9 , wherein the instrument controls execute procedures for accessing information on known compounds, integration procedures, correction procedures, compound information libraries, calibrations, internal standards, or any combinations thereof.
11. A sample analysis method, comprising:
providing components of a sample over time with a gas chromatography system;
partially or fully evacuating a sample cell;
collecting the components in the sample cell; and
obtaining current infrared spectra of the components in the sample cell with a Fourier transform infrared spectrometry system; and
maintaining background infrared spectra that include infrared spectra from previously eluted components and analyzing currently eluting components with reference to the background infrared spectra.
12. A method as claimed in claim 11 , wherein obtaining the current infrared spectra comprises obtaining absorption spectra.
13. A method as claimed in claim 11 , further comprising directing electromagnetic radiation in the sample cell along multiple paths.
14. A method as claimed in claim 11 , further comprising drawing at least a partial vacuum on the sample cell and sealing the sample cell to accumulate the components.