Augmented Raman analysis of a gas mixture
The present disclosure includes discloses a method for analyzing a multi-component gas sample using spectroscopy in combination with the measurement of extrinsic or intrinsic properties of the gas sample. The results of the spectroscopic analysis and the measurement are combined to quantify a gas component unseen by the spectroscopic analysis.
1. A method for analyzing the composition of a multi-component matter sample comprising:
determining a first composition of a multi-component matter sample using a spectroscopic device;
calculating a relative composition matrix containing a normalized molar amount of each component of the matter sample, based on the first composition;
calculating a value of a first secondary property of the matter sample using the relative composition matrix;
measuring a value of the first secondary property of the matter sample with a sensor embodied to measure the value of the first secondary property; and
determining whether a first difference between the calculated value of the first secondary property and the measured value of the first secondary property exceeds a first threshold,
wherein upon determining that the first difference exceeds the first threshold:
attributing the first difference to a component invisible to the spectroscopic device;
calculating a first amount of the spectroscopic-invisible component using the first difference;
adding the first amount of the spectroscopic-invisible component to the relative composition matrix; and
adjusting the normalized molar amount of each component in the relative composition matrix to account for the first amount of the spectroscopic-invisible component.
2. The method of claim 1 , wherein the spectroscopic device is a Raman spectroscopic device and spectroscopic-invisible is defined as invisible to Raman spectroscopy.
3. The method of claim 1 , wherein the spectroscopic device is a near infrared absorption spectroscopic device and spectroscopic-invisible is defined as invisible to near infrared absorption spectroscopy.
4. The method of claim 1 , wherein the spectroscopic device is an infrared absorption spectroscopic device and spectroscopic-invisible is defined as invisible to infrared absorption spectroscopy.
5. The method of claim 1 , wherein the matter is in a gaseous phase.
6. The method of claim 1 , wherein the matter is in a condensed phase.
7. The method of claim 1 , wherein the first secondary property is one of the following:
thermal conductivity, electrical conductivity, viscosity, pH, density, turbidity, and a color-changing chemical reaction.
8. The method of claim 1 , the method further comprising:
calculating a value of a second secondary property of the matter sample using the relative composition matrix, the second secondary property being different from the first secondary property;
measuring a value of the second secondary property of the matter sample with a sensor embodied to measure the value of the second secondary property; and
determining whether a second difference between the calculated value of the second secondary property and the measured value of the second secondary property exceeds a second threshold, wherein upon determining that the second difference exceeds the second threshold:
attributing the second difference to the spectroscopic-invisible component present in the sample;
calculating a second amount of the spectroscopic-invisible component using the second difference;
calculating a third amount of the spectroscopic-invisible component using the weighted average of the first amount of the spectroscopic-invisible component and the second amount of the spectroscopic-invisible component;
replacing the first amount of the spectroscopic-invisible component in the relative composition matrix with the third amount of the spectroscopic-invisible component; and
adjusting the normalized molar amounts of each component in the relative composition matrix to account for the third amount of the spectroscopic-invisible component.