High octane unleaded aviation gasoline

1. An unleaded aviation fuel composition having a MON of at least 99.6, sulfur content of less than 0.05 wt %, CHN content of at least 97.8 wt %, less than 2.2 wt % of oxygen content, a T10 of at most 75° C., T40 of at least 75° C., a T50 of at most 105° C., a T90 of at most 135° C., a final boiling point of less than 190° C., an adjusted heat of combustion of at least 43.5 MJ/kg, a vapor pressure in the range of 38 to 49 kPa, a freezing point of less than −58° C. comprising a blend comprising:

(a) from about 35 vol.% to about 55 vol.% of toluene having a MON of at least 107;

(b) from about 2 vol.% to about 10 vol.% of aniline;

(c) from about 15 vol.% to about 30 vol.% of at least one alkylate or alkyate blend having an initial boiling range of from about 32° C. to about 60° C. and a final boiling range of from about 105° C. to about 140° C., having T40 of less than 99° C., T50 of less than 100° C., T90 of less than 110° C. the alkylate or alkylate blend comprising isoparaffins from 4 to 9 carbon atoms, about 3-20 vol.% of C5 isoparaffins, about 3-15 vol.% of C7 isoparaffins, and about 60-90 vol.% of C8 isoparaffins, based on the alkylate or alkylate blend, and less than 1 vol % of C10+, based on the alkylate or alkylate blend;

(d) from about 4 vol.% to about 10 vol.% of an alcohol having a boiling point in the range of 80° C. to 140° C. and having 4 to 5 carbon numbers; and

(e) at least 8 vol.% of isopentane in an amount sufficient to reach a vapor pressure in the range of 38 to 49 kPa;

wherein the fuel composition contains less than 1 vol.% of C8 aromatics.

2. The unleaded aviation fuel composition of claim 1 wherein the total isopentane content in the blend of 10% to 26 vol %.

3. The unleaded aviation fuel composition of claim 1 having a potential gum of less than 6 mg/100 mL.

4. The unleaded aviation fuel composition of claim 1 wherein less than 0.2 vol % of ethers are present.

5. The unleaded aviation fuel composition of claim 2 further comprising an aviation fuel additive.

6. The unleaded aviation fuel composition of claim 1 wherein no alcohol having a boiling point of less than 80° C. is present.

7. The unleaded aviation fuel composition of claim 1 wherein the final boiling point is at most 180° C.

8. The unleaded aviation fuel composition of claim 1 wherein the alkylate or alkylate blend have a C10+ content of less than 0.1 vol % based on the alkylate or alkylate blend.

9. The unleaded aviation fuel composition of claim 1 wherein the alcohol is selected from the group consisting of iso-butanol, n-butanol, t-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol and mixtures thereof.

10. The unleaded aviation fuel composition of claim 1 wherein the alcohol have a boiling point in the range of 80° C. to 120° C.

11. The unleaded aviation fuel composition of claim 10 wherein the alcohol have a boiling point in the range of 90° C. to 120° C.

12. The unleaded aviation fuel composition of claim 10 wherein the alcohol is a C4 alcohol or a mixture thereof.

13. The unleaded aviation fuel composition of claim 10 wherein the alcohol is isobutanol.

14. The unleaded aviation fuel composition of claim 1 having water reaction within +/−2 mL as defined in ASTM D1094.

15. The unleaded aviation fuel composition of claim 9 wherein the alcohol is selected from the group consisting of iso-butanol, n-butanol, t-butanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol and mixtures thereof.

16. The unleaded aviation fuel composition of claim 10 wherein the alcohol is selected from the group consisting of iso-butanol, n-butanol, t-butanol, 2-pentanol, 3-pentanol, and mixtures thereof.