AVIATION GASOLINE COMPOSITIONS

Abstract

The present disclosure provides base aviation gasoline formulations. In addition, the present disclosure provides formulations in which one or more additives can optionally be added to the base aviation gasoline formulation to produce a finished aviation gasoline formulation.

Claims

1. A base aviation gasoline formulation comprising: i) dimethylbutane at a concentration between about 10% to about 40%; ii) trimethyl pentane at a concentration between about 50% to about 90%; and iii) isobutane at a concentration between about 1% to about 5%.

2. A formulation comprising the base aviation gasoline formulation of claim 1 and further comprising one or more additives.

3. The formulation of claim 2, wherein the additive is selected from the group consisting of m-toluidine, methylcyclopentadienyl manganese tricarbonyl (MMT), aniline, ethyl tert-butyl ether (ETBE), a corrosion inhibitor, a lubricity additive, one or more alcohols, and any combination thereof.

4. The formulation of claim 2, wherein the additive comprises m-toluidine.

5. The formulation of claim 2, wherein the additive comprises one or more alcohols.

6. The formulation of claim 5, wherein the one or more alcohols are selected from the group consisting of ethanol, propanol, isopropanol, n-butanol, isobutanol, and any combination thereof.

7. The formulation of claim 5, wherein the alcohol is isobutanol.

8. The formulation of claim 2, wherein the additives comprises m-toluidine and isobutanol.

9. The formulation of claim 2, wherein addition of the one or more additives provides a MON rating to a desired MON level, wherein the desired MON level is about 99.6.

10. The base aviation gasoline formulation of claim 1, wherein the formulation is substantially free of hydrocarbon-based aromatics.

11. A finished aviation gasoline formulation comprising: i) dimethylbutane at a concentration between about 10% to about 40%; ii) trimethyl pentane at a concentration between about 50% to about 90%; iii) isobutane at a concentration between about 1% to about 5%, and iv) two additives, wherein the two additives comprise a first additive and a second additive.

12. The finished aviation gasoline formulation of claim 11, wherein the first additive is selected from the group consisting of m-toluidine, methylcyclopentadienyl manganese tricarbonyl (MMT), aniline, ethyl tert-butyl ether (ETBE), a corrosion inhibitor, a lubricity additive, one or more alcohols, and any combination thereof.

13. The finished aviation gasoline formulation of claim 11, wherein the first additive is m-toluidine.

14. The finished aviation gasoline formulation of claim 11, wherein the second additive comprises one or more alcohols.

15. The finished aviation gasoline formulation of claim 11, wherein the second additive is selected from the group consisting of ethanol, propanol, isopropanol, n-butanol, isobutanol, and any combination thereof.

16. The finished aviation gasoline formulation of claim 11, wherein the second additive is isobutanol.

17. The finished aviation gasoline formulation of claim 11, wherein the first additive is m-toluidine and the second additive is isobutanol.

18. The finished aviation gasoline formulation of claim 11, wherein addition of the additives provides a MON rating to a desired MON level, wherein the desired MON level is about 99.6.

19. The finished aviation gasoline formulation of claim 11, wherein addition of the additives provides a MON rating to a desired MON level, wherein the desired MON level is less than 99.6 but in compliance with an ASTM D910-like specification (i.e. Specification Relief).

20. The finished aviation gasoline formulation of claim 11, wherein the formulation is substantially free of hydrocarbon-based aromatics.

Description

EXAMPLE 1

Preparation of Formulations

[0097] In one exemplary embodiment, the base aviation gasoline formulation comprises the following: dimethylbutane at 25%; trimethyl pentane at 71.5%; and isobutane at 3.5%. All percentages listed refer to volume percentages, unless otherwise noted.

[0098] The base aviation gasoline formulation can be combined with one or more additives to produce a finished aviation gasoline formulation that meet current ASTM D910 specifications. For example, a finished aviation gasoline formulation can comprise i) the base aviation gasoline formulation comprising dimethylbutane at 25%; trimethyl pentane at 71.5%; and isobutane at 3.5% and ii) m-toluidine at 2.0%. The percentage of components for this exemplary finished aviation gasoline formulation is thus as shown in Table 1:

[0099] In another example, a finished aviation gasoline formulation can comprise i) the base aviation gasoline formulation comprising dimethylbutane at 25%; trimethyl pentane at 71.5%; and isobutane at 3.5%, ii) m-toluidine at 2.0%, and iii) isobutanol at 3.0%. The percentage of components for this exemplary finished aviation gasoline product is as shown in Table 2:

EXAMPLE 2

Evaluation of Exemplary Formulations

[0100] In this example, various formulations were evaluated for distillation characteristics and other properties according to known ASTM evaluation methods. Five different formulations were evaluated and the results are presented in Table 3 and Table 4 below. All percentages listed refer to volume percentages, unless otherwise noted.

TABLE-US-00001 TABLE 3 GD170738 Second Lab GD170738 GD170738 60- Blend First Lab Blend GD161554 GD170738 40 2,2- 15 Dimethylbutane 2,3- 25.0 25.0 25.0 25.0 10 Dimethylbutane Isopentane 71.5 71.5 71.5 71.5 71.5 Toluene Trimethyl Pentane Isobutane 3.5 3.5 3.5 3.5 3.5 Base fuel 100.0 100.0 100.0 100.0 100.0 m-Toluidine 2.00% 2.00% 0% 2.00% 2.00%

TABLE-US-00002 TABLE 4 GD170738 GD170738 GD170738 GD170738 60-40 Second Lab First Lab ChemCAD ChemCAD Blend Blend GD161554 Simulation Simulation Specifications 2% m- 2% m- 0% m- 2% m- 2% m- Test Method Unit MIN MAX Toluidine Toluidine Toluidine Toluidine Toluidine Distillation, % ASTM D86 C. 41.4 41.7 39.5 59.7 56.9 Evap-IBP 5% C. 67.8 66.8 69.0 65.8 10% C. 75 75.2 75.6 74.8 75.6 72.4 20% C. 82.2 81.6 82.8 80.5 30% C. 86.0 84.9 86.6 85.3 40% C. 75 88.5 89.1 87.9 89.7 89.4 50% C. 105 91.5 92.4 90.9 92.8 93.2 60% C. 95.3 93.7 95.8 96.5 70% C. 97.6 95.9 98.5 99.2 80% C. 99.6 97.2 100.7 101.1 90% C. 135 100.3 101.4 97.7 102.5 102.6 95% C. 102.8 97.8 103.7 103.7 Distillation-EP C. 170 178.2 132.2 103.0 109.4 109.4 Recovery vol % 97.0 97.1 96.7 97.8 Residue vol % 1.5 1.1 2.1 0.9 Loss vol % 1.5 1 1.2 1.3 T10 + T50 ASTM D86 C. 135.0 166.7 168.0 168.4 Reid Vapor ASTM D5191 kPa 38 49 45.4 43.55 43.55 Pressure, E, (ASTM) Freeze Point ASTM D2386 C. 58.0 (Dixie) Freeze Point ASTM D2386 C. 58 (Haltermann) Motor Octane ASTM D2700 100.4 100.4 97.4 Number Supercharge ASTM D910 132.5

EXAMPLE 3

Analysis of Exemplary Formulations

[0101] In this example, an exemplary gasoline formulations was analyzed for compliance with the requirements for Grade 100LL detailed in Table 1 of ASTM D910-17a, entitled Standard Specification for Leaded Aviation Gasolines. The results of the analysis are presented in Table 5 and Table 6. All percentages listed refer to volume percentages, unless otherwise noted.

TABLE-US-00003 TABLE 5 Subject Test Property Sample Grade 100LL D3338 Net heat of combustion, 44.460 43.5 MIN MJ/kg D2700 Knock value, lean mixture Motor Octane Number 100.4 99.6 MIN Aviation Lean Rating 102.1 100.0 MIN D909 Knock value, rich mixture Performance number 135.2 130.0 MIN D2622 Sulfur, mass percent <0.0001 0.05 MAX D5059(c) Tetraethyl lead, g Pb/L <0.005 0.28 MIN, 0.56 MAX D2392 Color Any Blue

TABLE-US-00004 TABLE 6 Test Property Subject Sample All Grades D5191 Vapor pressure, 38 C., kPa 45.4 38.0 MIN, 49.0 MAX D4052 Density at 15 C., kg/m.sup.3 691.0 REPORT D86 Distillation, C. Initial boiling point 41.4 REPORT Fuel Evaporated 10 volume percent at C. 75.2 75 MAX 40 volume percent at C. 88.5 75 MIN 50 volume percent at C. 91.5 105 MAX 90 volume percent at C. 100.3 135 MAX Final boiling point 178.2 170 MAX Sum of 10% + 50% 166.7 135 MIN evaporated temperatures Recovery volume percent 97.9 97 MIN Residue volume percent 1.1 1.5 MAX Loss volume percent 1.0 1.5 MAX D2386 Freezing point, C. nd 58 MAX D130 Copper strip, 2 h at 100 C. 3a No. 1 MAX D873 Oxidation stability, mg/100 mL (5 h aging) Potential gum 3 6 MAX Lead precipitate <0.1 3 MAX D1094 Water reaction Volume change, mL 0.0 +/2 MAX D2624 Electrical conductivity, pSm 3 450 MAX

[0102] Regarding test D2386, behavior of the sample was atypical compared to normal hydrocarbon fuels. Analyst observations of the subject sample are summarized below. The temperature when the particles disappear is recorded as the observed freezing point.

[0103] On cooling:

TABLE-US-00005 Haze consistent throughout the sample 19 Sample removed from cooling bath 19

[0104] On warming:

TABLE-US-00006 Haze disappears 17

EXAMPLE 4

Analysis of Co-Solvent Additives

[0105] In various embodiments, a co-solvent additive can be included in the finished aviation gasoline formulation in order to address cold flow properties of the formulation. For example, a co-solvent additive such as an alcohol can be added in this regard.

[0106] This example provides a protocol for evaluation of various alcohols as co-solvents. In particular, alcohols can be added to the base aviation gasoline formulation (e.g., at 3% vol) and evaluated for i) MON, ii) T10, and iii) freezing point. The resultant analysis can provide the best alcohol or alcohols for achieving desirable cold flow properties of the formulation.