Patent ID: 7862628

Claim:
A hydrocarbonaceous fuel additive for a fuel composition comprising: a manganese-containing organometallic compound wherein the manganese-containing compound is selected from the following group: cyclopentadienyl manganese tricarbonyl, methylcyclopentadienyl manganese tricarbonyl, dimethylcyclopentadienyl manganese tricarbonyl, trimethylcyclopentadienyl manganese tricarbonyl, tetramethykyclopentadienyl manganese tricarbonyl, pentamethylcyclopentadienyl manganese tricarbonyl, ethylcyclopentadienyl manganese tricarbonyl, diethylcyclopentadienyl manganese tricarbonyl, propylcyclopentadienyl manganese tricarbonyl, isopropylcyclopentadienyl manganese tricarbonyl, tert-butylcyclopentadienyl manganese tricarbonyl, octylcyclopentadienyl manganese tricarbonyl, dodecylcyclopentadienyl manganese tricarbonyl, ethylmethylcyclopentadienyl manganese tricarbonyl, indenyl manganese tricarbonyl, and mixtures of two or more such compounds; an alkali metal compound; and a magnesium-containing compound, wherein the magnesium-containing compound is supplied in an amount sufficient to supply about 60 to 600 ppm of magnesium metal to the fuel composition.