Disclosed herein is a method for preparing a blended gasoline composition comprising: a) providing an automotive gasoline; and b) blending the automotive gasoline with an octane enhancer and with a pressurant, thereby making the blended gasoline composition; wherein the blended gasoline composition comprises an oxygen content, contributed by ethanol, in an amount that ranges from 0% by weight to 0.75% by weight, based on the total weight of the blended gasoline composition and the total oxygen content weight contribution of ethanol present in the blended gasoline composition; wherein the blended gasoline composition comprises an oxygen content, contributed by methanol, in an amount that ranges from 0% by weight to 0.1% by weight, based on the total weight of the blended gasoline composition and the total oxygen content weight contribution of methanol present in the blended gasoline composition; and wherein the blended gasoline composition comprises lead in an amount that ranges from 0 grams per gallon to 0.05 grams per gallon of the blended fuel composition. Also disclosed herein is the blended gasoline composition.

Disclosed herein is a method for preparing a blended gasoline composition comprising: a) providing an automotive gasoline; and b) blending the automotive gasoline with an octane enhancer and with a pressurant, thereby making the blended gasoline composition; wherein the blended gasoline composition comprises an oxygen content, contributed by ethanol, in an amount that ranges from 0% by weight to 0.75% by weight, based on the total weight of the blended gasoline composition and the total oxygen content weight contribution of ethanol present in the blended gasoline composition; wherein the blended gasoline composition comprises an oxygen content, contributed by methanol, in an amount that ranges from 0% by weight to 0.1% by weight, based on the total weight of the blended gasoline composition and the total oxygen content weight contribution of methanol present in the blended gasoline composition; and wherein the blended gasoline composition comprises lead in an amount that ranges from 0 grams per gallon to 0.05 grams per gallon of the blended fuel composition. Also disclosed herein is the blended gasoline composition.

A method for preparing a substituted fuel additive d is provided. The method comprises carrying out the following reaction: (a) (b) (d), The fuel additive d may be used as an octane-boosting additive in a fuel for a spark-ignition internal combustion engine. ##STR00001##

A method for preparing a substituted fuel additive d is provided. The method comprises carrying out the following reaction: (a) (b) (d), The fuel additive d may be used as an octane-boosting additive in a fuel for a spark-ignition internal combustion engine. ##STR00001##

An unleaded gasoline composition comprises, based on the total volume of the unleaded gasoline composition, 50 to 96 vol. % of an unleaded gasoline; 2 to 20 vol. % of a mixed butanol; and 2 to 30 vol. % of a distillate oil fraction comprising a paraffin, an olefin, a naphthene, and an aromatic at an initial boiling point cut of 180° C., wherein the unleaded gasoline, the mixed butanol, and the distillate oil fraction are selected to provide the unleaded gasoline composition with a Research Octane Number of 90 to 101, determined in accordance with ASTM D 2699; and a Motor Octane Number of 81.4 to 90, determined in accordance with ASTM D 2700.

An unleaded gasoline composition comprises, based on the total volume of the unleaded gasoline composition, 50 to 96 vol. % of an unleaded gasoline; 2 to 20 vol. % of a mixed butanol; and 2 to 30 vol. % of a distillate oil fraction comprising a paraffin, an olefin, a naphthene, and an aromatic at an initial boiling point cut of 180° C., wherein the unleaded gasoline, the mixed butanol, and the distillate oil fraction are selected to provide the unleaded gasoline composition with a Research Octane Number of 90 to 101, determined in accordance with ASTM D 2699; and a Motor Octane Number of 81.4 to 90, determined in accordance with ASTM D 2700.

A method for preparing a refinery fuel composition having a target octane number, comprises: (i) blending fuel components in proportions which are designed to give a refinery fuel composition with an octane number which is greater than the target octane number by a margin of less than 1; and (ii) testing the octane number of the refinery fuel composition and, if the octane number falls below the target octane number, blending the refinery fuel composition with a non-metallic octane-boosting additive. A further method comprises: (a) passing a first refinery fuel composition comprising a non-metallic octane-boosting additive to a fuel handing system, and discharging the first refinery fuel composition from the fuel handing system; and (b) passing a second refinery fuel composition to the fuel handing system.

A method for preparing a refinery fuel composition having a target octane number, comprises: (i) blending fuel components in proportions which are designed to give a refinery fuel composition with an octane number which is greater than the target octane number by a margin of less than 1; and (ii) testing the octane number of the refinery fuel composition and, if the octane number falls below the target octane number, blending the refinery fuel composition with a non-metallic octane-boosting additive. A further method comprises: (a) passing a first refinery fuel composition comprising a non-metallic octane-boosting additive to a fuel handing system, and discharging the first refinery fuel composition from the fuel handing system; and (b) passing a second refinery fuel composition to the fuel handing system.

A method for reducing the tendency of a hydrocarbon fluid to oxidise comprises combining an additive having a chemical structure comprising a 6-membered aromatic ring sharing two adjacent aromatic carbon atoms with a 6- or 7-membered saturated heterocyclic ring, the 6- or 7-membered saturated heterocyclic ring comprising a nitrogen atom directly bonded to one of the shared carbon atoms to form a secondary amine and an atom selected from oxygen or nitrogen directly bonded to the other shared carbon atom, the remaining atoms in the 6- or 7-membered heterocyclic ring being carbon with the hydrocarbon fluid. The additive may also be used for protecting a system in which a hydrocarbon fluid is used from the effects of oxidation.

A method for reducing the tendency of a hydrocarbon fluid to oxidise comprises combining an additive having a chemical structure comprising a 6-membered aromatic ring sharing two adjacent aromatic carbon atoms with a 6- or 7-membered saturated heterocyclic ring, the 6- or 7-membered saturated heterocyclic ring comprising a nitrogen atom directly bonded to one of the shared carbon atoms to form a secondary amine and an atom selected from oxygen or nitrogen directly bonded to the other shared carbon atom, the remaining atoms in the 6- or 7-membered heterocyclic ring being carbon with the hydrocarbon fluid. The additive may also be used for protecting a system in which a hydrocarbon fluid is used from the effects of oxidation.