High density cyclic fuels derived from linear sesquiterpenes

A method for making a blended fuel comprising a hydrogenated Diels-Alder cycloaddition adduct, comprising

• providing a feedstock comprising a linear sesquiterpene;
• producing a first mixture by metathesizing said feedstock from about 1 hour to about 24 hours using a metathesis catalyst at a temperature of from about 0° C. to about 150° C. under an inert-gas atmosphere, wherein said metathesizing yields methylcyclopentadiene (MCPD) and at least one branched-chain hydrocarbon;
• producing a second mixture by reacting said first mixture from about 0.3 hours to about 24 hours using a first acidic catalyst at a temperature of from about 15° C. to about 350° C., wherein said reacting yields at least one Diels-Alder cyclo-addition adduct;
• producing a third mixture by removing from said second mixture said first acidic catalyst;
• producing a fourth mixture by hydrogenating said third mixture from about 1 hour to about 24 hours with hydrogen gas at pressures ranging from about 1 atm to about 100 atm using a hydrogenation catalyst at a temperature of from about 0° C. to about 250° C. yielding a hydrogenated C9 hydrocarbon and at least one hydrogenated Diels-Alder cyclo-addition adduct, and distilling the hydrogenated C9 hydrocarbon and the at least one hydrogenated Diels-Alder cyclo-addition adduct to isolate the at least one hydrogenated Diels-Alder cycloaddition adduct, wherein said fourth mixture comprises the hydrogenated C9 hydrocarbon
• producing a fifth mixture by isomerizing said fourth mixture from about 0.3 hours to about 48 hours using a second acidic catalyst at temperatures ranging from about 15° C. to about 350° C. under an inert-gas atmosphere, wherein said isomerizing yields at least one alkyl-adamantane;
• and
• blending the at least one hydrogenated Diels-Alder cycloaddition adduct with a petroleum-based fuel to produce said blended fuel comprising a hydrogenated Diels-Alder cycloaddition adduct.