An aviation fuel is formulated with manganese-containing compounds. The composition may include relatively high amounts of manganese up to about 500 mg Mn/l. A manganese-containing additive may reduce the smoke created during the combustion of the aviation fuel. Additionally, the aviation fuel composition may include manganese to improve octane and include a phosphorus-containing scavenger to reduce manganese oxide engine deposits. Further, isooctane is added in order to, with the manganese-containing compound, improve the octane number of the fuel.

An aviation fuel is formulated with manganese-containing compounds. The composition may include relatively high amounts of manganese up to about 500 mg Mn/l. A manganese-containing additive may reduce the smoke created during the combustion of the aviation fuel. Additionally, the aviation fuel composition may include manganese to improve octane and include a phosphorus-containing scavenger to reduce manganese oxide engine deposits.

Additive composition mixtures and methods for synergistically maintaining low surface voltages of distillate fuels that include a synergistic conductivity improver additive composition for a distillate fuel. The additive composition includes: A) a mixture of (i) alkenyl polysulfone polymer, (ii) C16-C24 substituted maleic/polyamine copolymer, (iii) sulfonic acid, and (iv) aromatic solvent; and B) a mixture of (i) alkenyl polysulfone polymer, (v) polymeric reaction product of a C8-C18 aliphatic amine or diamine with epichlorohydrin; (iii) sulfonic acid, (iv) aromatic solvent; and optionally (vi) a quaternary ammonium compound. The additive composition contains from 30 to 60 wt. % component (A) and from 30 to 60 wt. % component (B) based on a total weight of the additive composition.