Fuel and lubricant compositions are provided that contain a primary low-speed pre-ignition (LSPI)-reducing additive comprising (i) an amino additive, (ii) an amine additive, (iii) a triazole additive, (iv) a benzamidinium additive, (v) a benzoxazole additive, or (vi) a NCX motif additive. Methods for preventing or reducing low speed pre-ignition events in spark-ignited engines using these compositions are also provided.

A compound represented by the formula: ##STR00001## wherein R is selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; (ii) substituted or unsubstituted aryl; and (iii) substituted and unsubstituted alkylaryl; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen and R.sup.2 and R.sup.3 may optionally be bridged by a polymethylene group; wherein when C=0 in R, the combined group R.sup.1 R.sup.2 is the same as the combined group R.sup.3 R.sup.4; and wherein when C=1 in R, each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are hydrogen.

A compound represented by the formula: ##STR00001## wherein R is selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; (ii) substituted or unsubstituted aryl; and (iii) substituted and unsubstituted alkylaryl; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen and R.sup.2 and R.sup.3 may optionally be bridged by a polymethylene group; wherein when C=0 in R, the combined group R.sup.1 R.sup.2 is the same as the combined group R.sup.3 R.sup.4; and wherein when C=1 in R, each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are hydrogen.

Unleaded aviation gasoline. An aviation gasoline fuel blend includes an unleaded aviation gasoline base fuel, with an effective amount of selected alkyl benzenes to improve the functional engine performance to avoid harmful detonation sufficient to meet or exceed selected standards for detonation performance requirements in full scale aircraft piston spark ignition engines designed for use with Grade 100LL avgas. Selected alkyl benzenes such as 1,3-dimethylbenzene, and/or 1,3,5-trimethylbenzene, or other mixtures thereof, may be used. Suitable alkylated benzenes may include a mixture of xylene isomers. Aromatic amines, such as m-toluidine, may also be added to increase MON. Base fuels may be a high quality aviation alkylate, or may be a commercial iso-octane, or a mixture of high quality aviation alkylate enhanced by commercial iso-octane, and may include iso-pentane or butane or both iso-pentane and butane in sufficient quantity to provide appropriate vapor pressure for the final fuel blend.

Unleaded aviation gasoline. An aviation gasoline fuel blend includes an unleaded aviation gasoline base fuel, with an effective amount of selected alkyl benzenes to improve the functional engine performance to avoid harmful detonation sufficient to meet or exceed selected standards for detonation performance requirements in full scale aircraft piston spark ignition engines designed for use with Grade 100LL avgas. Selected alkyl benzenes such as 1,3-dimethylbenzene, and/or 1,3,5-trimethylbenzene, or other mixtures thereof, may be used. Suitable alkylated benzenes may include a mixture of xylene isomers. Aromatic amines, such as m-toluidine, may also be added to increase MON. Base fuels may be a high quality aviation alkylate, or may be a commercial iso-octane, or a mixture of high quality aviation alkylate enhanced by commercial iso-octane, and may include iso-pentane or butane or both iso-pentane and butane in sufficient quantity to provide appropriate vapor pressure for the final fuel blend.

A fuel composition including a middle distillate fuel oil obtained from the distillation of a pyrolysis oil and, as an additive, one or more of: (a) an antioxidant; and (b) a stabilising additive selected from (x) alkoxylated amine compounds; (y) aldehyde-alkylphenol copolymers; (z) acylated nitrogen compounds; and mixtures thereof. Also disclosed are a method and use for improving the stability of a fuel composition comprising a middle distillate fuel oil obtained from the distillation of a pyrolysis oil, which involve adding to the composition one or more additives selected from (a) and (b).

A fuel composition including a middle distillate fuel oil obtained from the distillation of a pyrolysis oil and, as an additive, one or more of: (a) an antioxidant; and (b) a stabilising additive selected from (x) alkoxylated amine compounds; (y) aldehyde-alkylphenol copolymers; (z) acylated nitrogen compounds; and mixtures thereof. Also disclosed are a method and use for improving the stability of a fuel composition comprising a middle distillate fuel oil obtained from the distillation of a pyrolysis oil, which involve adding to the composition one or more additives selected from (a) and (b).

Compositions including a vegetable- or animal-derived oil, such as fatty acid alkyl esters, are stabilized against oxidation using an oxygenated aminophenol antioxidant. The aminophenol includes one or two carbon-containing group(s) including a hydroxyl group and/or ether group separated from the N atom by one or more carbon atoms. The oxygenated aminophenol antioxidants effective at controlling oxidation at moderate and even low amounts, useful in a variety of different oil and methyl ester fatty acid preparations, and were effective at elevated temperatures, and performed significantly better than convention antioxidants.

A compound represented by the formula: ##STR00001## wherein R is selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; (ii) substituted or unsubstituted aryl; and (iii) substituted and unsubstituted alkylaryl; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen and R.sup.2 and R.sup.3 may optionally be bridged by a polymethylene group; wherein when C=0 in R, the combined group R.sup.1 R.sup.2 is the same as the combined group R.sup.3 R.sup.4; and wherein when C=1 in R, each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are hydrogen.

A compound represented by the formula: ##STR00001## wherein R is selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; (ii) substituted or unsubstituted aryl; and (iii) substituted and unsubstituted alkylaryl; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen and R.sup.2 and R.sup.3 may optionally be bridged by a polymethylene group; wherein when C=0 in R, the combined group R.sup.1 R.sup.2 is the same as the combined group R.sup.3 R.sup.4; and wherein when C=1 in R, each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are hydrogen.