# Patent

## Title
Quantitative method for hydrocarbon analysis

## Abstract

A method for quantitative determination of hydrocarbon species in a hydrocarbon sample is disclosed. The method uses Townsend Discharge Nitric Oxide Chemical Ionization Gas Chromatography/Mass Spectrometry.

## Background
This application claims the benefit of U.S. Provisional Application No. 60/334,208 filed Nov. 29, 2001 the entire disclosure of which is hereby incorporated by reference.


FIELD OF THE INVENTION 
The invention relates to the quantitative determination of hydrocarbon species in hydrocarbon samples through the use of Townsend Discharge Nitric Oxide Chemical Ionization (TDNOCI) gas chromatography/mass spectrometry (GC/MS).
BACKGROUND OF THE INVENTION 
Traditional methods for the analysis of hydrocarbon samples require lengthy, complicated techniques that often do not provide sufficient information about the samples. Some involve a series of traps and multiple valves or columns (Paraffins, Iso-paraffins, Olefins, Naphthenes and Aromatics or PIONA), lengthy chromatographic programs (Detailed Hydrocarbon Analysis or DHA), and some only give boiling range information (Simulated Distillation or SIMDIST). The PIONA analysis does not accurately speciate some of the heavier components in gasolines (especially in the C9–C12 range), due to chromatographic overlapping of compounds and the lack of absolute standards for these species. Detailed Hydrocarbon Analysis (DHA) suffers from some of the same lack of specificity problems, and involves relatively lengthy analyses (up to 2 hours each). While SIMDIST provides accurate information on quantities of hydrocarbons within specific boiling ranges, it does not provide any speciation information on these hydrocarbons. A method is needed to provide quantitative information about complex hydrocarbon mixtures that includes speciation within various boiling point ranges. Such information would be particularly useful in the gasoline range.
Additionally, when using the available analytical techniques as described above, the hydrocarbon sample must first be distilled into a number of cuts. The cuts are then analyzed. This procedure requires:

    
    
        1) A large quantity of the sample for distillation, that may not be available.
        2) Distillation of the sample into multiple cuts
        3) Determination of the composition of each cut.

None of the typical compositional methods can provide accurate quantification for the high boiling range cuts (e.g., 204° C.+). It would be useful to provide a method that does not require separate cuts of the sample and one that can provide data for high boiling ranges.

    
    


The Townsend Discharge Nitric Oxide Chemical Ionization (TDNOCI) method has been developed and applied to kerosene and diesel range hydrocarbon samples as discussed in “Townsend Discharge Nitric Oxide Chemical Ionization Gas Chromatography/Mass Spectrometry for Hydrocarbon Analysis of the Middle Distillates”, I. Dzidic, H. A. Petersen, P. A. Wadsworth, and H. V. Hart, Analytical Chemistry, 1992, 64, pp. 2227–2232, which is hereby incorporated by reference.
Previously, this method was not applicable to gasoline range samples, as it did not provide for quantification or identification of olefinic hydrocarbons, which are commonly present (5–45 wt %) in catalytically or thermally cracked gasoline samples. Additionally, as mentioned above, PIONA and DHA analyses are not as specific as is desired for accurate quantification of heavier components in the gasoline samples. SMIDIST analysis alone does not provide specific hydrocarbon type data.
It would be advantageous to adopt the TDNOCI method for use with gasoline range samples including those with olefin constituents.
SUMMARY OF THE INVENTION 
The instant invention relates to a method of operating a calibrated gas chromatograph/mass spectrometer system for analysis of the chemical and physical properties of a complex mixture of hydrocarbons comprising:

    
    
        introducing a sample of the complex mixture of hydrocarbons into the gas chromatograph to partially separate the mixture into its constituent components;
        ionizing the resulting components via Townsend discharge nitric oxide chemical ionization;
        introducing the resulting ionized components into the mass spectrometer to produce corresponding mass spectra; and,
        measuring, from the resulting mass spectra, concentrations of individual hydrocarbon species and structural types within certain boiling ranges.
    
    




DETAILED DESCRIPTION OF THE INVENTION 
The instant invention provides quantitative information about complex hydrocarbon mixtures that includes hydrocarbon speciation in the boiling range between about 23° C. and about 260° C. by analyzing complex hydrocarbon samples (e.g., gasoline) with a boiling range between about 10° C. and about 705° C.
This method provides the concentrations of hydrocarbon species in a complex hydrocarbon mixture without prior separation by distillation into cuts as well as the distribution of the hydrocarbon species as a function of boiling point. The invention utilizes Townsend Discharge Nitric Oxide Chemical Ionization (TDNOCI) gas chromatography/mass spectrometry (GC/MS). This method has been used in the past for hydrocarbon analysis, but had been unable to determine olefin concentration or structural types. In this type of ionization, unique molecular ions are produced for each of the various hydrocarbon species. Complete chromatographic separation is not attained, but chromatographic separation along with mass separation allow for quantification of the individual species' homologues. Formulas I–III show characteristic ion molecule reactions for the various hydrocarbon types (species).

NO++M→(M−H)++HNO  (I)

NO++M→M++NO  (II)

NO++M→(MNO)+  (III)

Since little fragmentation occurs, quantification of molecular ions results in higher sensitivity along with higher specificity. Formula I is most characteristic for saturated hydrocarbons. Formula III predominates for aromatics with some of Formula I and II observed. Olefins show a mixed reaction of I, II and III.
An analysis software and analytical techniques are developed to determine the concentrations of individual hydrocarbon species, which are characterized by carbon number (C5–C15) as well as structural type (species). The species include, but are not limited to: n-Paraffins, iso-Paraffins, Cyclics, Branched mono Olefins, Linear mono Olefins, Diolefins, Cyclic Olefins, Cyclic Diolefins, Mono Aromatics, Indane/Indenes, Diaromatics, Dicyclics, and Benzothiophenes/Dibenzothiophenes. In addition, this method further quantifies the above species/carbon # groups within various boiling ranges (e.g., 45–65.5° C., 65.5–98.9° C., 98.9–154° C., 154–182° C., 182–204° C., 204–232° C., and 232+° C.). All of this quantitative information is obtained from a single injection of sample, either distillation cuts, or total liquid product (e.g., overhead samples from catalytic crackers, liquid products from hydrocrackers, or thermal conversion units, etc.).
The instant method is capable of quantifying all of the diverse hydrocarbon species within a typical gasoline range sample within a 30 minute chromatographic analysis, and with the same analysis, provides necessary “SIMDIST type” information. All of this is done with a single injection of sample. This analysis can be done on gasoline range samples, distillation cuts, or total liquid products (44.4–704° C.).
With the invention method, a hydrocarbon sample with a boiling range between about 44.4° C. to about 704° C. can be analyzed and the following information can be obtained:

    
    
        1) Hydrocarbon species by carbon number for the boiling range between about 44.4° C. to about 260° C. of the hydrocarbon sample;
        2) Hydrocarbon species as a function of boiling point for the boiling range between about 44.4° C. to about 260° C. of the hydrocarbon sample;
        3) Hydrocarbon species by carbon number in a number of narrow fractions (e.g., 45–65.5° C., 65.5–98.9° C., 98.9–154° C., 154–182° C., 182–204° C., 204–232° C., and 232+° C.)
    
    


This method can be routinely applied to the analysis of gasoline (full range) samples, gasoline fractions, and total liquid product samples. In addition, it can be applied to similar hydrocarbon samples (paraffins, olefins, naphtha, etc.) where characterization and quantification by hydrocarbon type is needed.
The new method described here accurately quantifies all hydrocarbon (carbon-hydrogen and some sulfur) species, including olefinic species, contained within gasoline range samples. In addition, it also yields quantitative “simdist” type data for the sample, without the additional cost of a separate SIMDIST analysis. And the need for distillation of the sample into a gasoline range fraction or fractions is eliminated by the ability of this method to analyze total liquid products without prior distillation.
The instant invention will be demonstrated by the following illustrative embodiments which are provided for illustration only and are not to be construed as limiting the invention.
EXAMPLE 1 
Initially, the method is calibrated using the standard procedure of the gas chromatograph/mass spectrometer (GC/MS) used for the analysis. A suitable GC/MS instrument is the Varian 1200 system from Varian Analytical Instruments. Table 1 gives a list of standard reference materials and their respective total concentrations used.







TABLE 1







Boiling Ranges wt % (a)















Boiling Range in deg. C.
46–65.5
65.5–98.9
98.9–154
154–182
182–204
204–232
232+
Total


















QA Gasoline
7.1
18.2
36.3
16.5
10
8.4
3.5
100.0


MWK Gasoline A
17.5
29.5
49.2
3.8
0.0
0.0
0.0
100.0


MWK Gasoline B
11.5
30.5
54.3
3.7
0.0
0.0
0.0
100.0


MWK Gasoline C
13.3
27.2
53.6
5.9
0.0
0.0
0.0
100.0


MWK Gasoline D
16.5
30.5
48.5
4.5
0.0
0.0
0.0
100.0










Combined Species Concentrations in wt % (b)
















Air
Air
Air

MWK A
MWK
MWK
MWK

















Liquide
Liquide
Liquide
QA GAS
AC REF
A
B
C
D
















Standard:
#9913
#9914
#9915
113–450
Lot#
113–310
113–310
113–310
113–310





Species
14.35
21.11
32.52
16.70
32.94
35.34
15.84
20.96
26.56


Paraffin ISO
0.76
1.96
3.10
3.06
8.25
3.31
1.87
1.99
2.67


Paraffin Normal
25.30
21.14
14.53
10.92
5.65
17.49
15.04
20.54
14.40


Mono Cyclic
0.95
2.60
3.66
15.13
5.28
13.86
23.92
11.17
18.42


Mono Olefin Branch
7.20
19.75
27.78
5.18
1.86
6.56
14.56
4.70
7.40


Mono Olefin Linear
0.18
0.49
0.68
2.05
0.65
0.00
0.00
0.00
0.00


Diolefin
0.00
0.00
0.00
6.57
1.60
4.11
13.62
6.79
5.37


Cyclic Olefin
0.00
0.00
0.00
0.27
0.29
0.00
0.00
0.00
0.00


Cyclic Diolefin
50.86
31.82
16.13
31.12
38.66
19.31
15.77
33.87
25.17


Mono


Aromatic Indans
0.00
0.00
0.00
7.08
3.03
0.00
0.00
0.00
0.00


Diaromatic
0.00
0.00
0.00
1.93
1.11
0.00
0.00
0.00
0.00


Dicyclic
0.00
0.00
0.00
0.28
0.08
0.00
0.00
0.00
0.00


Total
99.60
98.87
98.40
100.29
99.40
99.98
100.62
100.02
99.99





(a) From Simdist data


(b) From PIANO, DHAX, Air Liquide Certified wt %, and AC data






Each standard is analyzed repeatedly, under the standard operating conditions as listed in Table 2.







TABLE 2





Standard Operating Conditions


















CTC AS200SE Auto Sampler




Pull-up count = 10



Rinse Volume
= 8 ul



Injection Volume
= 1.5 ul



Pull-up speed
= 2.0 ul/sec



Air volume
= 1.0 ul



Post Injection Delay
= 2.0 sec



Solvent Cleaning Cycles
= 12




= Methylene Chloride



HP 6890 GC



Injector



Temp
= 280 deg. C Column



Head Pressure
= 14 psig Helium Split



Mode



Split Ratio
= 85



Gas Saver on at 1.0 minute



Oven



Initial temp
= 40 deg. C



Initial isothermal hold
= 3.1 minutes



Sequence 2 temp
= 82 deg. C



Rate
= 7.9 deg C/minute



Final temp.
= 240



Rate
= 9.9 deg C/minute



Final Isothermal hold
= 1.0 minute



Transfer Line



Temp
= 300 deg. C



Varian 1200 Mass Spectrometer



Scan range
= 66 Daltons to 266 Daltons



Scan time
= 0.3 seconds per scan



Mode
= Centroid Positive Chemical



Ionization



Source Temp
= 120 deg. C



Manifold Temp
= 40 deg. C



Discharge Ionization
= 1200 volts



Electron Multiplier
= 1100 volts



Nitric Oxide Source Pressure
= >5.3 torr










The averaged area percent (normalized to 100%) values for each individual standard along with their respective weight percent values was used to determine slope, intercept, and R2 values for each individual homologue of each individual species (for instance, C5 isoparaffins, C7 branched olefins, C7 linear olefins, etc). The slope and intercept values for these individual homologues of each individual species are then used to calculate concentrations from measured area percent values, according to Formula IV:

[(If (Y-intercept)>0, (Y-intercept),0))/slope]=X  (IV)

where Y is the area percent and X is the weight percent of a specific species homologue with respective slope and intercept. The selected slope and intercept values for each species homologue are stored within the species program, along with select ions, which are a representative of that particular species homologue. The hydrocarbon sample is then analyzed using the GC/MS as set up for chemical ionization using the TIDNOCI technique. The sample can be injected as a single cut taken from a crude oil or a gasoline sample. The total time per sample is about 30 minutes.

After analysis is complete, the data is further processed. First, the spectra are isotope corrected for the naturally occurring carbon-13 contribution from the lower mass ion. Next, sample calculations are performed and species information calculated.
Sample calculations are performed by determining the areas for each of the individual species homologue retention windows, by plotting the selected ions and integrating the areas under the ion chromatogram. This raw area information is then used to calculate combined area percentage values for all species homologues. Individual species homologues for specified boiling ranges are given in Tables 3–9.







TABLE 3







Individual Species Homologues for Boiling Range 45–65.5° C.










Ret Time



















Carbon

Window
Mass
Mass
Mass
Mass
Mass
Mass
Mass



















Species
Number
Slope
Intercept
Low
High
1
2
3
4
5
6
7






















Paraffin ISO
C5
1.09
0.016
3.15
3.35
71
0
0
0
0
0
0


Paraffin ISO
C6
0.94
0.389
4
4.45
85
0
0
0
0
0
0


Paraffin Normal
C5
0.00
0.005
3.4
3.5
71
0
0
0
0
0
0


Mono Cyclic
C5
1.00
0.038
4.05
4.15
69
0
0
0
0
0
0


Mono Olefin Branch
C5
1.30
0.557
3.05
3.2
69
70
100
0
0
0
0


Mono Olefin Branch
C5
1.30
0.557
3.37
3.44
69
70
100
0
0
0
0


Mono Olefin Branch
C5
1.30
0.557
3.9
3.63
69
83
100
0
0
0
0


Mono Olefin Branch
C6
0.84
0.000
3.3
4.36
69
70
84
114
0
0
0


Mono Olefin Linear
C5
2.88
0.000
3.44
3.37
69
70
100
0
0
0
0


Mono Olefin Linear
C5
2.88
0.000
4.36
3.57
69
83
100
0
0
0
0


Mono Olefin Linear
C6
2.29
0.269
4.36
4.5
69
83
84
86
114
0
0


Diolefin
C5
2.40
0.137
3.35
3.75
68
98
0
0
0
0
0


Cyclic Olefin
C5
1.99
0.008
3.9
4.1
67
0
0
0
0
0
0


Cyclic Diolefin
C5
1.00
0.005
3.7
3.85
66
0
0
0
0
0
0
















TABLE 4







Individual Species Homologues for Boiling Range 65.5–98.9° C.










Ret Time



















Carbon

Window
Mass
Mass
Mass
Mass
Mass
Mass
Mass



















Species
Number
Slope
Intercept
Low
High
1
2
3
4
5
6
7






















Paraffin ISO
C7
0.74
0.362
4.9
6.6
99
0
0
0
0
0
0


Paraffin Normal
C6
0.01
0.003
4.5
4.65
85
0
0
0
0
0
0


Paraffin Normal
C7
0.04
0.014
6.6
6.9
99
0
0
0
0
0
0


Mono Cyclic
C6
1.15
−0.360
5
5.9
83
0
0
0
0
0
0


Mono Cyclic
C7
1.02
1.114
6
6.55
97
0
0
0
0
0
0


Mono Olefin Branch
C6
0.84
0.557
4.45
4.59
69
83
84
86
114
0
0


Mono Olefin Branch
C6
0.84
0.557
4.68
4.8
69
83
84
86
114
0
0


Mono Olefin Branch
C6
0.84
0.557
4.9
5
69
83
84
86
114
0
0


Mono Olefin Branch
C7
0.23
0.442
4.9
6.41
86
98
100
128
0
0
0


Mono Olefin Branch
C7
0.23
0.442
6.5
6.62
86
98
100
128
0
0
0


Mono Olefin Branch
C7
0.23
0.442
6.87
7.01
86
98
100
128
0
0
0


Mono Olefin Branch
C7
0.23
0.442
7.1
7.35
86
98
100
128
0
0
0


Mono Olefin Linear
C6
2.29
0.269
4.59
4.68
69
83
84
86
114
0
0


Mono Olefin Linear
C6
2.29
0.269
4.8
4.9
69
83
84
86
114
0
0


Mono Olefin Linear
C7
0.44
0.259
6.41
6.5
86
98
100
128
0
0
0


Mono Olefin Linear
C7
0.44
0.259
6.62
6.87
86
98
100
128
0
0
0


Mono Olefin Linear
C7
0.44
0.259
7.01
7.1
86
98
100
128
0
0
0


Diolefin
C6
1.02
0.016
4.55
5.5
82
112
0
0
0
0
0


Cyclic Olefin
C6
1.10
0.029
5.5
5.9
81
82
0
0
0
0
0


Cyclic Olefin
C7
1.19
0.109
6.68
7.2
95
0
0
0
0
0
0


Cyclic Diolefin
C6
1.08
0.009
5
6
80
0
0
0
0
0
0


Mono Aromatic
C6
1.23
0.139
5.5
5.7
78
108
0
0
0
0
0


Thiophenes +
C4
5.00
0.020
5.6
5.72
84
114
0
0
0
0
0


Benzthio
















TABLE 5







Individual Species Homologues for Boiling Range 98.9–154° C.










Ret Time



















Carbon

Window
Mass
Mass
Mass
Mass
Mass
Mass
Mass



















Species
Number
Slope
Intercept
Low
High
1
2
3
4
5
6
7






















Paraffin ISO
C8
0.49
0.592
7.2
8.8
113
0
0
0
0
0
0


Paraffin ISO
C9
0.77
−0.170
9.8
11.6
127
0
0
0
0
0
0


Paraffin Normal
C8
0.10
0.015
9.35
9.6
113
0
0
0
0
0
0


Paraffin Normal
C9
0.32
0.000
11.95
12.2
127
0
0
0
0
0
0


Mono Cyclic
C7
1.02
1.114
7.2
7.7
97
0
0
0
0
0
0


Mono Cyclic
C8
1.08
0.623
7.2
9
111
0
0
0
0
0
0


Mono Cyclic
C8
1.08
0.623
9
10.5
111
0
0
0
0
0
0


Mono Cyclic
C9
1.57
−0.110
8.7
12.45
125
0
0
0
0
0
0


Mono Olefin
C8
0.27
0.135
7.3
9.07
86
100
112
142
0
0
0


Branch


Mono Olefin
C8
0.27
0.135
9.14
9.2
86
100
112
142
0
0
0


Branch


Mono Olefin
C9
0.18
0.107
10
11.6
86
100
114
126
156
0
0


Branch


Mono Olefin
C8
0.90
−0.048
9.07
9.14
69
83
86
100
112
114
142


Linear


Mono Olefin
C8
0.90
0.048
9.2
10
69
83
86
100
112
114
142


Linear


Mono Olefin
C9
0.68
0.023
11.6
12.45
86
100
114
1262
156
0
0


Linear


Diolefin
C7
1.13
0.011
7.2
9
96
0
0
0
0
0
0


Diolefin
C8
2.14
0.091
7.2
9.19
110
0
0
0
0
0
0


Diolefin
C8
2.14
0.091
9.2
11.5
110
0
0
0
0
0
0


Diolefin
C9
1.13
0.012
9
11
124
154
0
0
0
0
0


Diolefin
C9
1.13
0.012
11.01
12.45
124
154
0
0
0
0
0


Cyclic Olefin
C7
1.19
0.109
7.2
8.9
95
0
0
0
0
0
0


Cyclic Olefin
C8
2.20
0.022
7.2
9.7
109
0
0
0
0
0
0


Cyclic Olefin
C8
2.20
0.022
9.7
11.5
109
0
0
0
0
0
0


Cyclic Olefin
C9
0.60
0.197
10.3
12.45
123
0
0
0
0
0
0


Cyclic Olefin
C7
1.17
0.001
7.4
8
94
0
0
0
0
0
0


Cyclic Olefin
C8
1.27
−0.012
8
12.3
108
0
0
0
0
0
0


Mono Aromatic
C7
1.25
0.796
8.15
8.3
9.1
92
122
0
0
0
0


Mono Aromatic
C8
1.13
1.054
10.7
11.7
105
106
136
0
0
0
0


Mono Aromatic
C9
1.02
0.459
11.5
12.47
119
120
150
0
0
0
0






















Carbon

Ret Time
Mass
Mass
Mass
Mass
Mass
Mass
Mass




















Species
Number
Slope
Intercept
Window
1
2
3
4
5
6
7
0






















Thiophenes +
C5
1.50
0.000
8
+
98
128
0
0
0
0
0


Benzthio


Thiophenes +
C6
4.26
0.065
10
12
112
142
0
0
0
0
0


Benzthio
















TABLE 6







Individual Species Homologues for Boiling Range 154–182° C.










Ret Time



















Carbon

Window
Mass
Mass
Mass
Mass
Mass
Mass
Mass



















Species
Number
Slope
Intercept
Low
High
1
2
3
4
5
6
7






















Paraffin ISO
C10
0.51
0.074
11.4
14.1
141
0
0
0
0
0
0


Paraffin ISO
C11
0.61
0.014
13
15.05
155
0
0
0
0
0
0


Paraffin Normal
C10
0.39
0.012
14.2
14.5
141
0
0
0
0
0
0


Mono Cyclic
C9
1.57
−0.0110
12.45
13
125
0
0
0
0
0
0


Mono Cyclic
C10
0.93
0.074
12
15.05
139
0
0
0
0
0
0


Mono Olefin Branch
C10
0.13
0.100
12.4
13.8
86
114
128
140
170
0
0


Mono Olefin Branch
C10
0.13
0.100
14.2
14.7
86
114
128
140
170
0
0


Mono Olefin Branch
C11
0.14
0.062
13.5
15.05
154
184
0
0
0
0
0


Mono Olefin Linear
C10
0.81
0.002
13.8
14.2
86
114
128
140
170
0
0


Diolefin
C9
1.13
0.012
12.45
13.5
124
0
0
0
0
0
0


Diolefin
C10
1.11
0.006
12.45
15.05
138
0
0
0
0
0
0


Diolefin
C11
1.06
0.004
14.7
15.05
152
0
0
0
0
0
0


Cyclic Olefin
C9
0.60
0.197
12.45
13
123
0
0
0
0
0
0


Cyclic Olefin
C10
0.89
0.041
12.45
15.05
137
0
0
0
0
0
0


Mono Aromatic
C9
1.02
0.459
12.47
13
119
120
150
0
0
0
0


Mono Aromatic
C10
0.86
0.214
13.8
15.05
133
134
164
0
0
0
0


Indans
C9
1.10
0.092
13.9
14.05
116
117
118
148
0
0
0


Dicyclic
C9
0.96
0.039
13
14.43
123
0
0
0
0
0
0


Thiophenes +
C7
5.00
0.100
12.7
14.5
126
156
0
0
0
0
0


Benzthio
















TABLE 7







Individual Species Homologues for Boiling Range 182–204° C.










Ret Time



















Carbon

Window
Mass
Mass
Mass
Mass
Mass
Mass
Mass



















Species
Number
Slope
Intercept
Low
High
1
2
3
4
5
6
7






















Paraffin ISO
C11
0.61
0.014
15.05
16
155
0
0
0
0
0
0


Paraffin ISO
C12
0.45
−0.005
15.5
17.2
169
0
0
0
0
0
0


Paraffin Normal
C11
0.34
0.001
16.2
16.5
155
0
0
0
0
0
0


Mono Cyclic
C10
0.93
0.074
15.05
15.2
139
0
0
0
0
0
0


Mono Cyclic
C11
1.54
−0.002
15.44
17.2
153
0
0
0
0
0
0


Mono Olefin Branch
C11
0.14
0.062
15.05
16.7
154
184
0
0
0
0
0


Mono Olefin Branch
C12
0.05
0.028
15.76
17.2
168
198
0
0
0
0
0


Diolefin
C10
1.11
0.006
15.05
16.7
138
0
0
0
0
0
0


Diolefin
C11
1.06
0.004
15.05
17.2
152
0
0
0
0
0
0


Cyclic Olefin
C10
0.89
0.041
15.05
15.95
137
0
0
0
0
0
0


Cyclic Olefin
C11
0.47
0.002
15.5
17.2
151
0
0
0
0
0
0


Cyclic Olefin
C12
0.80
0.009
16.7
17.2
165
0
0
0
0
0
0


Mono Aromatic
C10
0.86
0.214
15.1
17.1
133
134
164
0
0
0
0


Mono Aromatic
C11
0.65
0.167
15
17.1
147
148
178
0
0
0
0


Indans
C9
1.10
0.092
14.8
15.6
116
117
118
146
148
0
0


Indans
C10
1.14
0.089
15.05
17.15
130
131
132
162
0
0
0


Indans
C11
1.11
0.120
15.44
17.2
145
146
176
0
0
0
0


Dicyclic
C10
0.55
0.005
15.95
16.8
137
0
0
0
0
0
0
















TABLE 8







Individual Species Homologues for Boiling Range 204–232° C.










Ret Time



















Carbon

Window
Mass
Mass
Mass
Mass
Mass
Mass
Mass



















Species
Number
Slope
Intercept
Low
High
1
2
3
4
5
6
7






















Paraffin ISO
C12
0.45
−0.005
17.2
17.9
169
0
0
0
0
0
0


Paraffin ISO
C13
0.56
0.020
17.2
19.5
183
0
0
0
0
0
0


Paraffin ISO
C14
0.51
0.017
19.1
19.7
197
0
0
0
0
0
0


Paraffin Normal
C12
0.22
0.005
18
18.4
169
0
0
0
0
0
0


Mono Cyclic
C12
0.31
0.038
17.2
19
167
0
0
0
0
0
0


Mono Cyclic
C13
1.07
0.017
18.6
19.7
181
0
0
0
0
0
0


Mono Olefin Branch
C13
0.20
0.028
17.2
18.6
182
212
0
0
0
0
0


Diolefin
C11
1.06
0.004
17.2
18.6
152
0
0
0
0
0
0


Cyclic Olefin
C12
0.80
0.009
17.2
17.7
165
0
0
0
0
0
0


Mono Aromatic
C10
0.86
0.214
17.1
17.6
133
134
164
0
0
0
0


Mono Aromatic
C11
0.65
0.167
17.1
19
147
148
178
0
0
0
0


Mono Aromatic
C12
0.51
0.044
17.5
19.8
161
162
192
0
0
0
0


Mono Aromatic
C13
0.85
0.035
24.9
25
175
176
206
0
0
0
0


Indans
C10
1.14
0.089
17.15
17.5
130
131
132
162
0
0
0


Indans
C11
1.11
0.120
17.2
19.8
144
145
146
176
0
0
0


Indans
C12
1.01
0.114
17.2
19.7
159
160
190
0
0
0
0


Indans
C13
1.10
0.011
17.9
19.7
173
174
204
0
0
0
0


Diaromatic
C10
2.40
0.005
17.7
18
128
0
0
0
0
0
0


Diaromatic
C11
2.36
0.009
19.5
20.2
142
0
0
0
0
0
0


Dicyclic
C11
0.64
0.010
17.2
18.6
151
0
0
0
0
0
0


Dicyclic
C12
0.88
0.007
17.7
18.6
165
0
0
0
0
0
0


Thiophenes +
C8
6.57
0.153
17.7
18.1
134
0
0
0
0
0
0


Benzthio
















TABLE 9







Individual Species Homologues for Boiling Range 232+ ° C.










Ret Time



















Carbon

Window
Mass
Mass
Mass
Mass
Mass
Mass
Mass



















Species
Number
Slope
Intercept
Low
High
1
2
3
4
5
6
7






















Paraffin ISO
C14
0.51
0.017
19.7
21.2
197
0
0
0
0
0
0


Paraffin ISO
C15
0.36
0.016
20.5
22.6
211
0
0
0
0
0
0


Paraffin Normal
C13
0.23
0.004
19.65
20
183
0
0
0
0
0
0


Paraffin Normal
C14
0.20
0.003
21.2
21.5
197
0
0
0
0
0
0


Paraffin Normal
C15
0.18
0.004
22.6
23.05
211
0
0
0
0
0
0


Mono Cyclic
C13
1.07
0.017
19.7
20.7
181
0
0
0
0
0
0


Mono Cyclic
C14
1.04
0.022
19.7
22.5
195
0
0
0
0
0
0


Mono Aromatic
C13
0.85
0.035
19.63
21.2
175
176
206
0
0
0
0


Indans
C12
1.01
0.114
19.7
21.9
159
160
190
0
0
0
0


Indans
C13
1.10
0.011
19.7
22
173
174
204
0
0
0
0


Diaromatic
C12
2.31
0.009
21
22.3
156
0
0
0
0
0
0


Thiophenes +
C9
5.90
0.241
19.35
20.5
148
0
0
0
0
0
0


Benzthio


Thiophenes +
C10
1.72
0.002
20.4
22
162
0
0
0
0
0
0


Benzthio









Precision is determined by analysis of a QA gasoline on a daily basis using the instant method. A table of average values, standard deviation, and relative standard deviation for species and boiling range totals as determined by the analyses of this QA gasoline is presented in Table 10.










TABLE 10







Standard
Percent Relative


Species
Average
Deviation
Standard Deviation


















Paraffin ISO
15.80
0.57
3.59


Paraffin Normal
2.22
0.18
8.27


Mono Cyclic
12.41
0.58
4.68


Mono Olefin Branch
14.37
0.50
3.48


Mono Olefin Linear
8.92
1.52
17.00


Diolefin
1.00
0.10
9.84


Cyclic Olefin
7.61
0.37
4.83


Cyclic Diolefin
0.21
0.06
25.92


Mono Aromatic
28.57
1.50
5.25


Indans
6.73
0.55
8.20


Diaromatic
1.74
0.19
10.91


Dicyclic
0.26
0.02
8.59


Thiophenes
0.15
0.02
14.53


Boiling Ranges (° C.)


45–65.5
7.84
2.01
25.67


65.5–98.9
22.29
1.56
6.99


98.9–154
30.95
1.26
4.08


154–182
15.96
0.86
5.39


182–204
10.53
0.92
8.72


204–232
8.40
0.67
7.95


232+
4.03
0.85
21.12









Precision calculations are made for repetitive analyses of a QA gasoline sample. These results indicate that precision for components in the 5–45% concentration range generally have approximately 3–7% relative standard deviation. This QA sample is also used as a QC sample. If any of the values monitored fall out of the two sigma range, routine maintenance is undertaken to bring subsequent analyses of the QA sample into the two sigma range.
Tables 11 and 12 show a comparison of the analysis of select standard reference samples by this method, and by PIANO, DHAX, and ASTM Aromatics analyses. Table 11 shows totals by species and Table 12 shows totals by carbon number.







TABLE 11







A Comparison of Analyses Results for 4 MWK Gasolines















ASTM


Totals by Species
TDNOCI


AROMATICS


wt %
GC/MS
PIANO
DHAX
Analyses














MWK A






n-Paraffins
3.86
3.30
3.93


l-paraffins
36.59
35.36
39.54


Olefins
22.53
24.54
19.12


Naphthenes
17.69
17.49
18.70


Aromatics
19.33
19.31
18.71
17.93


Total:
100.00
100.00
100.00


MWK B


n-Paraffins
3.09
1.87
4.31


l-paraffins
11.85
15.85
23.06


Olefins
55.63
51.46
40.83


Naphthenes
13.89
15.05
16.38


Aromatics
15.54
15.88
15.42
13.53


Total:
100.00
100.11
100.00


MWK C


n-Paraffins
2.29
1.98
2.85


l-paraffins
20.20
20.95
26.66


Olefins
22.07
22.66
18.27


Naphthenes
19.61
20.53
20.05


Aromatics
35.84
33.87
32.17
31.82


Total:
100.00
99.99
100.00


MWK D


n-Paraffins
2.37
2.67
3.68


l-paraffins
28.25
26.46


Olefins
30.93
31.19
25.52


Naphthenes
13.82
14.40
15.21


Aromatics
24.63
25.17
24.35
23.99


Total:
100.00
99.89%
100.00%
















TABLE 12







Totals by Carbon #












Wt %
TDNOCI GC/MS
PIANO
DHAX
















MWK A






C5
5.07
5.98
6.02



C6
25.62
26.36
24.24



C7
30.97
30.61
31.57



C8
27.07
25.99
27.05



C9
8.60
9.54
8.83



 C10
1.06
1.21
2.11



 C11
0.63
0.22
0.18



 C12
0.64
0.07
0.00



 C13
0.27
0
0.00



MWK B



C5
4.91
3.72
5.13



C6
24.72
27.07
22.42



C7
30.66
29.14
30.45



C8
24.18
26.26
27.40



C9
12.04
11.08
12.02



 C10
1.35
1.71
2.28



 C11
0.79
0.21
0.26



 C12
0.87
0.30
0.03



 C13
0.34
0.48
0.00



MWK C



C5
3.86
4.75
4.87



C6
24.25
24.57
22.53



C7
29.75
30.67
31.65



C8
28.92
28.89
30.63



C9
9.45
9.26
5.89



 C10
1.76
1.25
4.07



 C11
0.83
0.21
0.34



 C12
0.76
0.16
0.03



 C13
0.33
0.25
0.00



MWK D
*



C5
5.61
5.50
6.06



C6
30.27
29.33
26.10



C7
31.61
30.70
32.33



C8
24.12
24.93
26.24



C9
7.26
8.04
6.35



 C10
0.77
1.06
2.61



 C11
0.17
0.19
0.28



 C12
0.10
0.12
0.02



 C13
0.09
0.11
0.00










Table 13 shows an example of a typical final report format for the instant method.








TABLE 13







Boiling range











(° C.)
45–65.5 wt % total = 5.8
65–98.9 wt % total = 18.5
98.9–154 wt % total = 33.2






















Species
C4
C5
C6
Total
C4
C6
C7
Total
C4
C5
C6
C7
C8
C9
Total

























PARAFFIN ISO
0.0
8.5
45.2
53.7
0.0
0.0
17.1
17.1
0.0
0.0
0.0
0.0
9.2
7.6
16.9


PARAFFIN NORMAL
0.0
0.0
0.0
0.0
0.0
1.9
2.1
4.0
0.0
0.0
0.0
0.0
1.3
1.2
2.6


MONO CYCLIC
0.0
0.0
0.0
0.0
0.0
8.3
4.5
12.9
0.0
0.0
0.0
3.1
9.0
4.7
16.8


MONO OLEFIN BRANCH
0.0
18.2
12.0
30.2
0.0
16.7
20.2
37.0
0.0
0.0
0.0
0.0
5.2
3.3
8.5


MONO OLEFIN LINEAR
0.0
8.1
5.3
13.4
0.0
4.8
7.2
12.0
0.0
0.0
0.0
0.0
1.7
0.6
2.4


DIOLEFIN
0.0
0.0
0.0
0.0
0.0
0.7
0.0
0.7
0.0
0.0
0.0
0.8
0.2
0.3
1.2


CYCLIC OLEFIN
0.0
2.7
0.0
2.7
0.0
7.7
4.8
12.5
0.0
0.0
0.0
3.6
1.9
0.9
6.5


CYCLIC DIOLEFIN
0.0
0.0
0.0
0.0
0.0
0.2
0.0
0.2
0.0
0.0
0.0
0.1
0.3
0.0
0.4


MONO AROMATIC
0.0
0.0
0.0
0.0
0.0
3.7
0.0
3.7
0.0
0.0
0.0
14.1
30.1
0.3
44.5


INDANS
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0


DIAROMATIC
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0


DICYCLIC
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0


Thiophenes
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.3
0.0
0.0
0.0
0.0
0.3


Total
0.0
37.5
62.5
100.0
0.0
44.1
55.9
100.0
0.0
0.3
0.0
21.7
58.9
19.1
100.0













Boiling range
Summed and Renormalized



(° C.)
45–154
















Species
C4
C5
C6
C7
C8
C9
Total




















PARAFFIN ISO
0.0
0.9
4.5
5.5
5.3
4.4
20.6



PARAFFIN NORMAL
0.0
0.0
0.6
0.7
0.8
0.7
2.8



MONO CYCLIC
0.0
0.0
2.7
3.3
5.2
2.7
13.9



MONO OLEFIN BRANCH
0.0
1.8
6.6
6.5
3.0
1.9
19.8



MONO OLEFIN LINEAR
0.0
0.8
2.1
2.3
1.0
0.4
6.6



DIOLEFIN
0.0
0.0
0.2
0.4
0.1
0.2
0.9



CYCLIC OLEFIN
0.0
0.3
2.5
3.6
1.1
0.5
8.1



CYCLIC DIOLEFIN
0.0
0.0
0.1
0.0
0.2
0.0
0.3



MONO AROMATIC
0.0
0.0
1.2
8.1
17.4
0.2
26.9



INDANS
0.0
0.0
0.0
0.0
0.0
0.0
0.0



DIAROMATIC
0.0
0.0
0.0
0.0
0.0
0.0
0.0



DICYCLIC
0.0
0.0
0.0
0.0
0.0
0.0
0.0



Thiophenes
0.0
0.2
0.0
0.0
0.0
0.0
0.2



Total
0.0
3.9
20.5
30.5
34.1
11.0
100.0














Boiling range
154–182 wt % total = 17.6
182–204 wt % total = 11.6
204–232 wt % total = 11.4
























Species
C7
C9
C10
C11
Total
C9
C10
C11
C12
Total
C8S
C10
C11
C12
C13
C14
Total



























PARAFFIN ISO
0.0
0.0
10.9
2.2
13.1
0.0
0.0
5.2
2.4
7.6
0.0
0.0
0.0
3.3
3.5
0.2
7.1


PARAFFIN NORMAL
0.0
0.0
2.5
0.0
2.5
0.0
0.0
3.0
0.0
3.0
0.0
0.0
0.0
3.8
0.0
0.0
3.8


MONO CYCLIC
0.0
0.8
5.0
0.0
5.8
0.0
0.2
1.3
0.0
1.5
0.0
0.0
0.0
2.5
0.4
0.0
2.9


MONO OLEFIN BRANCH
0.0
0.0
2.4
0.3
2.8
0.0
0.0
0.8
0.0
0.8
0.0
0.0
0.0
0.0
0.0
0.0
0.0


MONO OLEFIN LINEAR
0.0
0.0
0.3
0.0
0.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0


DIOLEFIN
0.0
0.2
0.1
0.0
0.3
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.0


CYCLIC OLEFIN
0.0
0.9
0.9
0.0
1.8
0.0
0.4
1.3
0.1
1.8
0.0
0.0
0.0
0.1
0.0
0.0
0.1


CYCLIC DIOLEFIN
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0


MONO AROMATIC
0.0
71.3
1.4
0.0
72.7
0.0
49.9
8.7
0.0
58.6
0.0
2.8
20.4
12.3
0.0
0.0
35.4


INDANS
0.0
0.1
0.0
0.0
0.1
9.5
15.5
1.5
0.0
26.5
0.0
9.8
19.4
3.9
0.2
0.0
33.3


DIAROMATIC
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
8.7
8.0
0.0
0.0
0.0
16.7


DICYCLIC
0.0
0.6
0.0
0.0
0.6
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.2
0.0
0.0
0.3


Thiophenes
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.4
0.0
0.0
0.0
0.0
0.0
0.4


Total
0.0
73.9
23.5
2.5
100.0
9.5
66.1
21.9
2.5
100.0
0.4
21.2
48.0
26.1
4.0
0.2
100.0















Boiling range
232+ wt % total = 2.0
Boiling
%


















Species
C9S
C10S
C12
C13
C14
C15
Total
Ranges
wt






















PARAFFIN ISO
0.0
0.0
0.0
0.0
11.4
0.0
11.4
 45–65.5
5.8



PARAFFIN NORMAL
0.0
0.0
0.0
47.8
0.0
0.0
47.8
65.5–98.9
18.5



MONO CYCLIC
0.0
0.0
0.0
2.5
0.6
0.0
3.0
98.9–154 
33.2



MONO OLEFIN BRANCH
0.0
0.0
0.0
0.0
0.0
0.0
0.0
154–182
17.6



MONO OLEFIN LINEAR
0.0
0.0
0.0
0.0
0.0
0.0
0.0
182–204
11.6



DIOLEFIN
0.0
0.0
0.0
0.0
0.0
0.0
0.0
204–232
11.4



CYCLIC OLEFIN
0.0
0.0
0.0
0.0
0.0
0.0
0.0
232+
2.0



CYCLIC DIOLEFIN
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Total
100.0



MONO AROMATIC
0.0
0.0
0.0
7.0
0.0
0.0
7.0



INDANS
0.0
0.0
19.4
2.9
0.0
0.0
22.4



DIAROMATIC
0.0
0.0
0.0
0.0
0.0
0.0
0.0



DICYCLIC
0.0
0.0
0.0
0.0
0.0
0.0
0.0



Thiophenes
8.3
0.1
0.0
0.0
0.0
0.0
8.3



Total
8.3
0.1
19.4
60.3
12.0
0.0
100.0













Thiophenes and











Totals

benzthiophenes













By Species
wt %
By Carbon #
wt %
Totals


















PARAFFIN ISO
15.9
C4
0.0
C4
0.0



PARAFFIN NORMAL
3.3
C5
2.2
C5
0.1



MONO CYCLIC
9.4
C6
12.5
C6
0.0



MONO OLEFIN BRANCH
12.4
C7
18.1
C7
0.0



MONO OLEFIN LINEAR
4.0
C8
18.6
C8
0.1



DIOLEFIN
0.6
C9
18.8
C9
0.1



CYCLIC OLEFIN
5.3
C10
15.2
C10
0.0



CYCLIC DIOLEFIN
0.2
C11
9.5
Total
0.2



MONO AROMATIC
38.4
C12
3.9



INDANS
8.1
C13
1.1



DIAROMATIC
2.1
C14
0.1



DICYCLIC
0.1
C15
0.0



Thiophenes
0.2
Total
100.0



Total
100.0


















TABLE 14







A Comparison of TDNOCI GC/MS, SIMDIST, and Distillation


Data for Boiling Range wt %


TDNOCI GC/MS DATA










Sample:














Boiling Ranges (° C.)
A
B
C
D
E
F
















 45–65.5
5.8
8.9
10.8
10.3
5.6
4.6


65.5–98.9
18.5
19.1
20.3
19.2
19.7
22.9


98.9–154 
33.2
31.1
30.9
30.8
35.7
29.2


154–182
17.6
17.0
17.0
18.2
16.2
15.7


182–204
11.6
10.9
10.5
10.6
8.9
11.6


204–232
13.4
13.0
10.5
10.9
14.0
16.0


Total:
100.0
100.0
100.0
100.0
100.0
100.0










Measured SYMDIST Data










Sample:














Boiling Ranges (° C.)


C

E
F
















 45–65.5


8.6

4.7
3.5


65.5–98.9


18.5

15.7
18.2


98.9–154 


34

35.4
31.5


154–182


17.8

16.7
16.8


182–204


11.2

11.3
13.5


204–232


9.9

16.2
16.5


Total:


100.0

100.0
100.0










Distillation Cut Data










Sample:














Boiling Ranges (° C.)
A
B
C
D
E
F
















 45–65.5
6.5
9.2
18.9
11.8
8.4
7.8


65.5–98.9
18.6
22.3
14.7
16.9
17.4
19.3


98.9–154 
32.7
30.7
31.4
34.0
33.2
29.7


154–182
17.3
16.0
16.8
15.9
15.7
15.8


182–204
11.7
10.0
9.5
10.6
10.0
11.9


204–232
13.3
11.8
8.7
10.8
15.3
15.5


Total:
100.0
100.0
100.0
100.0
100.0
100.0

## Claims

1. A method of operating a calibrated gas chromatograph/mass spectrometer system for analysis of the chemical and physical properties of a complex mixture of hydrocarbons with a boiling range between about 10° C. and about 705° C., said complex mixture of hydrocarbons comprising gasoline and olefins, which method includes hydrocarbon speciation in the boiling range between about 23° C. and about 260° C., said method comprising:
introducing a sample of the complex mixture of hydrocarbons into the gas chromatograph to (partially) separate the mixture into its constituent components;
ionizing the resulting components via Townsend discharge nitric oxide chemical ionization;
introducing the resulting ionized components into the mass spectrometer to produce corresponding mass spectra; and,
measuring, from the resulting mass spectra, the concentrations of individual hydrocarbon species and structural types comprising n-paraffins, iso-paraffins, cyclics, branched mono olefins, linear mono olefins, diolefins, cyclic olefins, cyclic diolefins, mono aromatics, indane/indenes, diaromatics, dicyclics, and benzothiophenes/dibenzothiophenes with in certain boiling ranges.

2. The method of claim 1 in which the mass spectrometer is a quadrupole mass spectrometer.

3. The method of claim 1 in which the sample of the complex mixture of hydrocarbons is selected from the group consisting of full range gasoline, gasoline fractions, distillation cuts and total liquid products.

4. The method of claim 1 in which the boiling ranges measured comprise: about 45° C. to about 65° C., about 65° C. to about 99° C., about 99° C. to about 154° C., about 154° C. to about 182° C., about 182° C. to about 204° C., about 204° C. to about 232° C., and about 232° C. to about 260° C.

5. The method of claim 1 in which the concentrations of the specified individual hydrocarbon species and structural types are measured by the following method comprising:
calibrating the GC/MS according to the standard procedure of the GC/MS; analyzing each standard repeatedly;
calculating a slope and a y-intercept for each homologue of each individual species from an averaged area percent value along with a weight percent value;
calculating concentrations from measured area percent values, according to Formula IV


[(If (Y-intercept)>0, (Y-intercept),0))/slope]=X  (IV)


 where Y is the area percent and X is the weight percent of a specific species homologue with respective slope and intercept;
analyzing the hydrocarbon sample using the GC/MS to produce a spectrum;
correcting the spectrum for the naturally occurring carbon-13 contribution from the lower mass ion; and,
performing sample calculations using the method comprising:
determining the areas for each of the individual species homologue retention windows by integrating the areas under the ion chromatogram and comparing to the standards.

6. The method of claim 5 in which the mass spectrometer is a quadrupole mass spectrometer.

7. The method of claim 5 in which the sample of the complex mixture of hydrocarbons is selected from the group consisting of full range gasoline, gasoline fractions, distillation cuts and total liquid products.

8. The method of claim 5 in which the boiling ranges measured comprise: about 45° C. to about 65° C., about 65° C. to about 99° C., about 99° C. to about 154° C., about 154° C. to about 182° C., about 182° C. to about 204° C., about 204° C. to about 232° C., and about 232° C. to about 260° C.

9. The method of claim 5 further comprising:
measuring precision;
measuring accuracy; and,
checking quality control.