Fuel markers and methods of producing and using same
A method of forming a composition comprising contacting a fuel and at least one compound of Formula I: wherein X is carbon, oxygen, or sulfur; R 1 and R 2 each independently are hydrogen, a C 1 to C 20 alkyl, or a C 6 to C 10 aryl; R 3 and R 3′ each independently are hydrogen or a C 1 to C 4 alkyl; R 4 and R 4′ each independently are hydrogen, a C 1 to C 4 alkyl, a C 4 to C 10 cycloalkyl, or a C 6 to C 10 aryl; R 5 and R 5′ each independently are a C 4 to C 10 alkyl; R 6 and R 6′ each independently are hydrogen or a C 1 to C 6 alkyl; and R 7 and R 7′ each independently are hydrogen or C 1 to C 4 alkyl; and wherein the compound of Formula I when subjected to GC-MS using electron ionization at greater than 70 eV produces at least one ion having a mass-to-charge ratio of 300 to 600.
1. A method of forming a composition comprising contacting (a) a fuel and (b) at least one compound characterized by Formula I:
wherein X can be carbon (C), oxygen (O), or sulfur (S); wherein, when X is C, R 1 and R 2 can each independently be hydrogen, a C 1 to C 20 alkyl group, or a C 6 to C 10 aryl group, and wherein the C 6 to C 10 aryl group is a hydrocarbon; wherein, when X is O or S, R 1 and R 2 are lone non-bonding electron pairs; R 3 and R 3′ can each independently be hydrogen or a C 1 to C 4 alkyl group; R 4 and R 4′ can each independently be hydrogen, a C 1 to C 4 alkyl group, a C 4 to C 10 cycloalkyl group, or a C 6 to C 10 aryl group; R 5 and R 5′ can each independently be a C 4 to C 10 alkyl group; R 6 and R 6′ can each independently be hydrogen or a C 1 to C 6 alkyl group; and R 7 and R 7′ can each independently be hydrogen or a C 1 to C 4 alkyl group;
and wherein the compound characterized by Formula I when subjected to gas chromatography—mass spectrometry (GC-MS) using electron ionization produces at least one ion having a mass-to-charge ratio of from about 300 to about 600 at an ionization energy of equal to or greater than about 70 eV.
2. The method of claim 1 wherein X is O and wherein the compound characterized by Formula I has Structure A:
3. The method of claim 1 wherein X is S and wherein the compound characterized by Formula I has any of Structures B-F:
4. The method of claim 1 wherein X is C and R 1 and R 2 each independently are selected from the group consisting of a methyl group, an ethyl group, a n-propyl group, an iso-propyl group, a n-butyl group, an iso-butyl group, a sec-butyl group, a tort-butyl group, a pentyl group, a n-pentyl group, an iso-pentyl group, a sec-pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group and a nonadecyl group.
5. The method of claim 1 wherein the compound characterized by Formula I has any of Structures G-O:
6. The method of claim 1 wherein X is C and R 1 and R 2 can each independently be hydrogen, a C 1 to C 10 alkyl group, or a C 6 to C 10 aryl group.
7. The method of claim 6 wherein the C 6 to C 10 aryl group is phenyl, a substituted phenyl, tolyl, a substituted tolyl, xylyl or a substituted xylyl.
8. The method of claim 6 wherein the compound characterized by Formula I has Structure P:
9. The method of claim 1 wherein X is C and R 3 and R 3′ can each independently be a methyl group or hydrogen.
10. The method of claim 1 wherein X is C and R 4 , and R 4′ can each independently be a C 1 to C 10 alkyl group, a C 4 to C 10 cycloalkyl group, or a C 6 to C 10 aryl group.
11. The method of claim 10 wherein R 5 and R 5′ are both a pentyl group or a heptyl group.
12. The method of claim 10 wherein the C 4 to C 10 cycloalkyl group is a cyclobutyl group, a substituted cyclobutyl group, a cyclopentyl group, a substituted cyclopentyl group, a cyclohexyl group, a substituted cyclohexyl group, a cycloheptyl group, a substituted cycloheptyl group, a cyclooctyl group, or a substituted cyclooctyl group.
13. The method of claim 1 wherein X is C, R 1 and R 2 are a methyl group, and R 5 and R 5′ are both a C 4 to C 10 alkyl group.
14. The method of claim 1 wherein the fuel comprises gasoline, diesel, jet fuel, kerosene, non-petroleum derived fuels, alcohol fuels, ethanol, methanol, propanol, butanol, biodiesel, maritime fuels, or combinations thereof.
15. The method of claim 1 wherein the compound characterized by Formula I is present in the composition in an amount of from about 1 ppb to about 50 ppm, based on the total weight of the composition.
16. The method of claim 1 wherein the composition comprises at least 2 compounds characterized by Formula I.
17. The method of claim 16 further comprising (i) acquiring a fuel sample; (ii) subjecting the fuel sample to GC-MS to yield GC-MS data; and (iii) comparing the GC-MS data of the fuel sample with the GC-MS data of the composition.
18. The method of claim 17 further comprising determining an amount of the compound characterized by Formula I present in the composition and the fuel sample based on the GC-MS data.
19. The method of claim 1 further comprising subjecting the composition to surface enhanced Raman scattering spectroscopy.
20. The method of claim 1 further comprising subjecting the composition to nuclear magnetic resonance spectroscopy.
21. The method of claim 1 wherein R 3 and R 3′ are hydrogen.