A multipurpose fuel composition is disclosed which contains a petroleum derived jet fuel component and a renewable jet fuel component, wherein the multipurpose fuel composition has a freezing point of −40° C. or below, and an exemplary cetane number more than 40, preferably more than 45, more preferably more than 50.

A diamondoid fuel comprising a cage structure including 10, 14, 18, or 22 carbons. The diamondoid fuel also includes one of one to four cyclopropyl groups bonded to the cage structure or two to four functional groups bonded to the cage structure where the functional groups are an alkyl group, an allyl group, a cyclopropyl group, or combinations thereof. Additionally, at least one functional group is an allyl group and at least one functional group is a cyclopropyl group.

A diamondoid fuel comprising a cage structure including 10, 14, 18, or 22 carbons. The diamondoid fuel also includes one of one to four cyclopropyl groups bonded to the cage structure or two to four functional groups bonded to the cage structure where the functional groups are an alkyl group, an allyl group, a cyclopropyl group, or combinations thereof. Additionally, at least one functional group is an allyl group and at least one functional group is a cyclopropyl group.

A fuel composition for use in internal-combustion engines has a fuel component, an alcohol component, a water component, a microemulsion blend, and a cetane-enhancer component. The microemulsion blend includes at least one of lower grade fatty acid derivatives being present in an amount effective for the fuel, alcohol, and water components to form a microemulsion blend. The emulsifier is present in an amount effective for the biodiesel fuel, alcohol, water, and emulsifier to form an emulsion.

A fuel composition for use in internal-combustion engines has a fuel component, an alcohol component, a water component, a microemulsion blend, and a cetane-enhancer component. The microemulsion blend includes at least one of lower grade fatty acid derivatives being present in an amount effective for the fuel, alcohol, and water components to form a microemulsion blend. The emulsifier is present in an amount effective for the biodiesel fuel, alcohol, water, and emulsifier to form an emulsion.

A fuel for an internal combustion engine includes a fatty alkyl ether having a formula corresponding to formula (II): ##STR00001##
wherein x is 1-8, and y is 0 to 3; and the alkyl is an alkyl group having a number of carbon atoms that is less than the number of carbon atoms in the alkyl chain on the opposite side of the oxygen atom. The fatty alky ether can be used as a neat fuel or blend with biodiesel, diesel, ethanol or other fuels. The fatty alkyl ethers are improved in cetane number and cold flow properties over a biodiesel with fatty acid methyl acid methyl ester compounds. This is particularly valuable for compression ignition engines. A method of combustion in several types of engines is also disclosed.

A fuel for an internal combustion engine includes a fatty alkyl ether having a formula corresponding to formula (II): ##STR00001##
wherein x is 1-8, and y is 0 to 3; and the alkyl is an alkyl group having a number of carbon atoms that is less than the number of carbon atoms in the alkyl chain on the opposite side of the oxygen atom. The fatty alky ether can be used as a neat fuel or blend with biodiesel, diesel, ethanol or other fuels. The fatty alkyl ethers are improved in cetane number and cold flow properties over a biodiesel with fatty acid methyl acid methyl ester compounds. This is particularly valuable for compression ignition engines. A method of combustion in several types of engines is also disclosed.

The invention discloses novel diesel fuel compositions including a renewable paraffinic diesel component, a fossil diesel component and an oxygenate component, as well as methods for manufacture and use of a combination of a renewable paraffinic diesel component, and an oxygenate component for reducing NOx emissions.

The invention discloses novel diesel fuel compositions including a renewable paraffinic diesel component, a fossil diesel component and an oxygenate component, as well as methods for manufacture and use of a combination of a renewable paraffinic diesel component, and an oxygenate component for reducing NOx emissions.

The present disclosure relates to a composition that includes a compound having the structure R.sub.1O—(CH.sub.2O).sub.n—R.sub.2 and a cetane number between about 65 and about 100, where n is between 1 and 10, inclusively, R.sub.1 includes a first alkyl group, and R.sub.2 includes a second alkyl group.