Method of improving the oxidative stability of a lubricating composition which is used to lubricate a spark ignition internal combustion engine, the spark-ignition engine being comprised within the powertrain of a hybrid electric vehicle, wherein the method comprises the step of introducing into the combustion chamber of the spark-ignition engine a gasoline composition wherein the gasoline composition comprises a hydrocarbon base fuel containing 10 to 20% v olefins, not greater than 5% v olefins of at least 10 carbon atoms, and not greater than 5% v aromatics of at least 10 carbon atoms, based on the base fuel, initial boiling point in the range 30 to 40 C., T10 in the range 45 to 57 C., T50 in the range 82 to 104 C., T90 in the range 140 to 150 C. and final boiling point not greater than 220 C.

A fuel composition including a fuel oil obtained from the distillation of a pyrolysis oil having a boiling point distribution within the gasoline range 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 including a fuel oil obtained from the distillation of a pyrolysis oil, having a boiling point distribution within the gasoline range, which involve adding to the composition one or more additives selected from (a) and (b).

The disclosed technology relates to a concentrated multi-functional additive that can be continuously dosed in internal combustion engines.

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.

The use of tetrahydrobenzoxazines I ##STR00001##
where R.sup.1 is a hydrocarbyl radical and R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are each independently hydrogen atoms, hydroxyl groups or hydrocarbyl radicals, and where R.sup.2 to R.sup.5 may also form a second and a third tetrahydrooxazine ring, with the proviso that at least one of the substituents has from 4 to 3000 carbon atoms and the remaining substituents, when they are hydrocarbyl radicals, each have from 1 to 20 carbon atoms, as stabilizers for stabilizing inanimate organic material, especially turbine fuels, against the action of light, oxygen and heat.

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 each R is independently selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each independently 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 independently selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; and wherein one of R.sup.1 and R.sup.2 and one of R.sup.3 and R.sup.4 may optionally be bridged by a polymethylene group to form a cycloalkyl; 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.

New compositions and certain corresponding components are useful for reducing crystallization of paraffin crystals in fuels.

Antidegradant compounds are disclosed, and methods of making them, that are represented by the formula I: ##STR00001## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen. Also disclosed are diimine intermediates corresponding to formula III: ##STR00002## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen. These intermediates themselves exhibit antidegradant activity.

A quaternary ammonium salt detergent made from the reaction product of the reaction of: (a) polyalkene-substituted amine having at least one tertiary amino group; and (b) a quaternizing agent suitable for converting the tertiary amino group to a quaternary nitrogen and the use of such quaternary ammonium salt detergents in a fuel composition to reduce intake valve deposits.