Characterization of crude oil by time of flight mass spectrometry
A system and computer program product are provided for calculating one or more indicative properties, e.g., one or more of the cetane number, octane number, pour point, cloud point, octane number, and aniline point of oil fractions, from the density and time of flight mass spectrometry (TOF-MS) of a sample of an oil sample.
1. A system for assigning an indicative property to a gas oil fraction or a naphtha fraction of an oil sample, wherein the oil sample is selected from the group consisting of crude oils, bitumens, heavy oils and shale oils, the system comprising:
a time of flight mass spectrometer (TOF-MS) that outputs TOF-MS data;
a non-volatile memory device that stores software program modules and data, the data including TOF-MS data representative of cumulative mass fraction data;
a processor coupled to the memory device;
a first software program module, executed by the processor, that processes TOF-MS data derived by the time of flight mass spectrometer from the crude oil sample, wherein the processing includes the calculation of an TOF-MS index (TOFMSI) as a weighted average of the TOF-MS data; and
a second software program module that derives the indicative property of the gas oil fraction or the naphtha fraction, as a function of the TOFMSI and a density of the oil sample.
2. A method for operating a computer to assign an indicative property to a gas oil fraction or a naphtha fraction of an oil sample, wherein the oil sample is selected from the group consisting of crude oils, bitumens, heavy oils and shale oils, the method comprising:
deriving from the oil sample time of flight mass spectrometry (TOF-MS) data from a time of flight mass spectrometer (TOF-MS), the TOF-MS data representative of cumulative mass fraction data;
obtaining a density of the oil sample;
entering into the computer the density of the oil sample and the TOF-MS data;
calculating an TOF-MS index (TOFMSI) as a weighted average of the TOF-MS data; and
deriving the indicative property gas oil fraction or the naphtha fraction as a function of the TOFMSI and the density of the oil sample.
3. A method for operating a computer to assign an indicative property to a gas oil fraction or a naphtha fraction of an oil sample, wherein the oil sample is selected from the group consisting of crude oils, bitumens, heavy oils and shale oils, the method comprising:
deriving from the oil sample time of flight mass spectrometry (TOF-MS) data from a time of flight mass spectrometer (TOF-MS), the TOF-MS data representative of cumulative mass fraction data;
obtaining a density of the oil sample;
entering into the computer the density of the oil sample and the TOF-MS data;
calculating an TOF-MS index (TOFMSI) as a weighted average of the TOF-MS data; and
deriving the indicative property of the gas oil fraction, the naphtha fraction, or the oil sample as a function of the TOFMSI and the density of the oil sample.
4. The method as in claim 2 , wherein the weighted average of the TOF-MS data is according to the equation
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where M=mass, and W=cumulative mass fraction.
5. The method of claim 2 , wherein the oil sample is crude oil.
6. The method of claim 2 , wherein the oil sample is obtained from an oil well, stabilizer, extractor, or distillation tower.
7. The method of claim 2 , wherein the indicative property is a cetane number.
8. The method of claim 2 , wherein the indicative property is a pour point.
9. The method of claim 2 , wherein the indicative property is a cloud point.
10. The method of claim 2 , wherein the indicative property is an aniline point.
11. The method of claim 2 , wherein the indicative property is an octane number.
12. The method of claim 2 , wherein plural indicative properties are calculated including at least two indicative properties selected from the group consisting of cetane number, pour point, cloud point, aniline point and octane number.
13. The method of claim 2 , wherein the indicative property is of a gas oil fraction.
14. The method of claim 2 , wherein the indicative property is of a naphtha fraction.
15. The method of claim 2 , wherein the TOF-MS data is over a mass-to-charge ratio range of 90-3000 m/z.
16. The method as in claim 3 , wherein the weighted average of the TOF-MS data is according to the equation
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where M=mass, and W=cumulative mass fraction.
17. The method of claim 3 , wherein the oil sample is crude oil.
18. The method of claim 3 , wherein the indicative property is a cetane number, a pour point, a cloud point, or an aniline point of a gas oil fraction.
19. The method of claim 3 , wherein the indicative property is an octane number of a naphtha fraction.
20. The method of claim 3 , wherein the TOF-MS data is over a mass-to-charge ratio range of 90-3000 m/z.