METHODS FOR CLASSIFICATION OF HYDROCARBON MIXTURES

• US 20200132640A1
• Filed: 12/26/2019
• Published: 04/30/2020
• Est. Priority Date: 10/26/2018
• Status: Active Grant

• Current Assignee: Purdue Research Foundation (The Trustees of Purdue University (d/b/a Purdue University))
• Original Assignee: Purdue Research Foundation (The Trustees of Purdue University (d/b/a Purdue University))
• Inventors: Kilaz, Gozdem, Vozka, Petr
• Granted Patent: US 11,513,104 B2
• Time in Patent Office: Days
• CPC Class Codes: G01N 2030/025 Gas chromatography
• CPC Class Codes: G01N 2030/8854 involving hydrocarbons
• CPC Class Codes: G01N 30/463 for multidimensional chromatography
• CPC Class Codes: G01N 30/68 Flame ionisation detectors
• CPC Class Codes: G01N 30/8606 Integration
• CPC Class Codes: G01N 30/8682 Group type analysis, e.g. of components having structural properties in common
• CPC Class Codes: G01N 30/8696 Details of Software
• CPC Class Codes: G01N 33/28 Oils , i.e. hydrocarbon liquidsgaseous fuels G01N33/225; edible oils or edible fats G01N33/03

Abstract

Methods for classification of hydrocarbon mixtures that include performing two-dimensional gas chromatography on a hydrocarbon mixture to obtain a chromatogram using a two-dimensional gas chromatograph equipped with a flame ionization detector, a reversed phase column configuration with a primary mid-polar or polar column and a secondary non-polar column, and a standard mixture. Classification is performed in which groups of hydrocarbons are identified and labeled based on peaks associated with the standard mixture, after which a quantification process is performed.

Claims

1. A method of classification of a hydrocarbon mixture, the method comprising:

performing two-dimensional gas chromatography on the hydrocarbon mixture to obtain a chromatogram displaying peaks associated with hydrocarbons within the hydrocarbon mixture using a two-dimensional gas chromatograph (GC×

GC) system comprising a flame ionization detector (FID), a reversed phase column configuration with a primary mid-polar or polar column and a secondary non-polar column, and a standard mixture of hydrocarbon compounds;

using gas chromatography imaging and data processing software, performing a classification process to group the hydrocarbons displayed in the chromatogram into groups with the same carbon number from the same hydrocarbon class, wherein the groups are identified and labeled based on hydrocarbon peaks associated with the standard mixture; and

performing a quantification process that includes summing the peak areas of the hydrocarbons in each group classified in the chromatogram to determine a total peak area of each group and then calculating the weight percent of each group by dividing the total peak area of the group by the total peak area of the hydrocarbon mixture;

wherein the classification process is performed without using mass spectrometry.

2. The method of claim 1, wherein the standard mixture consists of a plurality of the following twenty-four hydrocarbon compounds:

n-octane, n-dodecane, n-hexadecane, perhydrophenalene, tetradecahydroanthracene, toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, n-hexylbenzene, indan, 4,7-dimethylindan, 1,1-dimethyltetralin, 1,1,6-trimethyltetralin, naphthalene, 2-methylnaphthalene, 1,8-dimethylnaphthalene, biphenyl, 4-methylbiphenyl, 4,4-dimethylbiphenyl, phenanthrene, 1-methylanthracene, pyrene, and 1-methylpyrene.

3. The method of claim 1, wherein the standard mixture consists of the following hydrocarbon compounds:

n-octane, n-dodecane, n-hexadecane, perhydrophenalene, tetradecahydroanthracene, toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, n-hexylbenzene, indan, 4,7-dimethylindan, 1,1-dimethyltetralin, 1,1,6-trimethyltetralin, naphthalene, 2-methylnaphthalene, 1,8-dimethylnaphthalene, biphenyl, 4-methylbiphenyl, 4,4-dimethylbiphenyl, phenanthrene, 1-methylanthracene, pyrene, and 1-methylpyrene.

4. The method of claim 1, wherein the classification process includes grouping n-paraffins by:

viewing a first chromatogram of the standard mixture in the gas chromatography imaging and data processing software, wherein hydrocarbons are displayed with increasing carbon number from left to right across the first chromatogram;

identifying n-paraffins in the first chromatogram to establish peak locations for use as n-paraffin standards;

overlaying borders on the first chromatogram corresponding to the n-paraffin standards;

viewing a second chromatogram of the hydrocarbon mixture in the gas chromatography imaging and data processing software wherein hydrocarbons are displayed with increasing carbon number from left to right across the second chromatogram and the borders corresponding to the n-paraffin standards are overlaid thereon;

adjusting the colors of the second chromatogram to isolate n-paraffins displayed thereon; and

identifying and labeling groups of the n-paraffins displayed in the second chromatogram based on the borders drawn corresponding to the n-paraffin standards.

5. The method of claim 3, wherein the classification process includes grouping isoparaffins by:

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the n-paraffins overlaid thereon;

adjusting the colors of the second chromatogram to isolate isoparaffins; and

overlaying borders on the second chromatogram corresponding to groups of the isoparaffins, wherein the borders are determined based on peak locations of the isoparaffins which elute between and/or above the n-paraffins and directly to the left of a corresponding one of the n-paraffins having the same carbon number as the carbon number of the respective one of the groups of the isoparaffins.

6. The method of claim 5, wherein the classification process includes grouping monocycloparaffins by:

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins and isoparaffins overlaid thereon;

adjusting the colors of the second chromatogram to isolate monocycloparaffins; and

overlaying borders on the second chromatogram corresponding to groups of the monocycloparaffins, wherein the borders are determined based on peak locations of the monocycloparaffins which elute between and/or below the n-paraffins and directly to the right of a corresponding one of the n-paraffins having the same carbon number as the carbon number of the respective one of the groups of monocycloparaffins, wherein the borders of the n-paraffins and the groups of the monocycloparaffins of the same carbon number intercept.

7. The method of claim 6, wherein the classification process includes grouping dicycloparaffins by:

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins, isoparaffins, and monocycloparaffins overlaid thereon;

adjusting the colors of the second chromatogram to isolate dicycloparaffins;

overlaying borders on the second chromatogram corresponding to groups of the dicycloparaffins, wherein the borders are determined based on peak locations of the dicycloparaffins which elute directly to the right of a corresponding one of the groups of monocycloparaffins having a carbon number one less than the carbon number of the respective one of the groups of the dicycloparaffins.

8. The method of claim 7, wherein the classification process includes grouping tricycloparaffins by:

viewing the first chromatogram in the gas chromatography imaging and data processing software;

identifying and labeling peaks associated with perhydrophenalene and tetradecahydroanthracene;

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the n-paraffins, isoparaffins, monocycloparaffins, and dicycloparaffins and the peaks associated with perhydrophenalene and tetradecahydroanthracene overlaid thereon; and

overlaying borders on the second chromatogram corresponding to groups of the tricycloparaffins, wherein the borders are determined based on peak locations of the tricycloparaffins which elute directly to the right of a corresponding one of the groups of the dicycloparaffins having a carbon number one less than the carbon number of the respective one of the groups of the tricycloparaffins and by using the peaks associated with perhydrophenalene and tetradecahydroanthracene as visual aids.

9. The method of claim 8, wherein the classification process includes grouping alkylbenzenes by:

viewing the first chromatogram in the gas chromatography imaging and data processing software;

identifying and labeling peaks associated with toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, and n-hexylbenzene;

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins, isoparaffins, monocycloparaffins, dicycloparaffins, and tricycloparaffins and the peaks associated with toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, and n-hexylbenzene overlaid thereon; and

overlaying borders on the second chromatogram corresponding to groups of the alkylbenzenes, wherein the peaks associated with toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, and n-hexylbenzene are used as visual aids for overlaying the borders of the groups of the alkylbenzenes.

10. The method of claim 9, wherein the classification process includes grouping cycloaromatics by:

viewing the first chromatogram in the gas chromatography imaging and data processing software;

identifying and labeling peaks associated with indan, 4,7-dimethylindan, 1,1-dimethyltetralin, and 1,1,6-trimethyltetralin;

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins, isoparaffins, monocycloparaffins, dicycloparaffins, tricycloparaffins, and alkylbenzenes and the peaks associated with indan, 4,7-dimethylindan, 1,1-dimethyltetralin, and 1,1,6-trimethyltetralin overlaid thereon; and

overlaying borders on the second chromatogram corresponding to groups of the cycloaromatics, wherein the borders are determined based on peak locations of the cycloaromatics which elute directly to the right of a corresponding one of the groups of the alkylbenzenes having the same carbon number as the carbon number of the respective one of the groups of the cycloaromatics and by using the peaks associated with indan, 4,7-dimethylindan, 1,1-dimethyltetralin, and 1,1,6-trimethyltetralin as visual aids.

11. The method of claim 10, wherein the classification process includes grouping alkynaphthalenes by:

viewing the first chromatogram in the gas chromatography imaging and data processing software;

identifying and labeling peaks associated with naphthalene, 2-methylnaphthalene, and 1,8-dimethylnaphthalene;

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins, isoparaffins, monocycloparaffins, dicycloparaffins, tricycloparaffins, alkylbenzenes, and cycloaromatics and the peaks associated with naphthalene, 2-methylnaphthalene, and 1,8-dimethylnaphthalene overlaid thereon; and

overlaying borders on the second chromatogram corresponding to groups of the alkynaphthalenes, wherein the borders are determined based on peak locations of the alkynaphthalenes which elute directly to the right of a corresponding one of the groups of the cycloaromatics having the same carbon number as the carbon number of the respective one of the groups of the alkynaphthalenes and by using the peaks associated with naphthalene, 2-methylnaphthalene, and 1,8-dimethylnaphthalene as visual aids.

12. The method of claim 11, wherein the classification process includes grouping biphenyls by:

viewing the first chromatogram in the gas chromatography imaging and data processing software;

identifying and labeling peaks associated with biphenyl, 4-methylbiphenyl, and 4,4-dimethylbiphenyl;

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins, isoparaffins, monocycloparaffins, dicycloparaffins, tricycloparaffins, alkylbenzenes, cycloaromatics, and alkynaphthalenes and the peaks associated with biphenyl, 4-methylbiphenyl, and 4,4-dimethylbiphenyl overlaid thereon; and

overlaying borders on the second chromatogram corresponding to groups of the biphenyls, wherein the borders are determined based on peak locations of the biphenyls which elute directly to the right of a corresponding one of the groups of the alkynaphthalenes having a carbon number one less than the carbon number of the respective one of the groups of the biphenyls and by using the peaks associated with biphenyl, 4-methylbiphenyl, and 4,4-dimethylbiphenyl as visual aids.

13. The method of claim 12, wherein the classification process includes grouping anthracenes and phenanthrenes by:

viewing the first chromatogram in the gas chromatography imaging and data processing software;

identifying and labeling peaks associated with phenanthrene and 1-methylanthracene;

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins, isoparaffins, monocycloparaffins, dicycloparaffins, tricycloparaffins, alkylbenzenes, cycloaromatics, alkynaphthalenes, and biphenyls and the peaks associated with phenanthrene and 1-methylanthracene overlaid thereon; and

overlaying borders on the second chromatogram corresponding to groups of the anthracenes and phenanthrenes, wherein the borders are determined based on peak locations of the anthracenes and phenanthrenes which elute directly to the right of a corresponding one of the groups of the biphenyls having a carbon number one less than the carbon number of the respective one of the groups of the anthracenes and phenanthrenes and by using the peaks associated with phenanthrene and 1-methylanthracene as visual aids.

14. The method of claim 13, wherein the classification process includes grouping pyrenes by:

viewing the first chromatogram in the gas chromatography imaging and data processing software;

identifying and labeling peaks associated with phenanthrene and 1-methylanthracene;

viewing the second chromatogram in the gas chromatography imaging and data processing software with the borders corresponding to the groups of the n-paraffins, isoparaffins, monocycloparaffins, dicycloparaffins, tricycloparaffins, alkylbenzenes, cycloaromatics, alkynaphthalenes, biphenyls, anthracenes, and phenanthrenes and the peaks associated with phenanthrene and 1-methylanthracene overlaid thereon; and

overlaying borders on the second chromatogram corresponding to groups of the pyrenes, wherein the borders are determined based on peak locations of the pyrenes which elute directly to the right of a corresponding one of the groups of the anthracenes and phenanthrenes having the same carbon number as the carbon number of the respective one of the groups of the pyrenes and by using the peaks associated with phenanthrene and 1-methylanthracene as visual aids.

15. The method of claim 1, wherein the hydrocarbon mixture has a carbon number in a range of C6 through C33.

16. The method of claim 1, wherein the hydrocarbon mixture is an aviation fuel.

17. The method of claim 1, wherein the hydrocarbon mixture is a diesel fuel.

18. The method of claim 1, wherein the GC×

GC system does not comprise a mass spectrometer.