Patent ID: 8057558

Claim:
A method for improving low-temperature properties of a biodiesel fuel, said method comprising the steps of: a) providing a biodiesel fuel comprising unsaturated ester molecules; b) treating the biodiesel fuel so as to react at least some of the unsaturated ester molecules contained therein with an oxidizing species to convert at least some of the unsaturated ester molecules to epoxy-ester species and provide for an epoxy-ester-containing biodiesel fuel; and c) reacting at least some of the epoxy-ester species in the epoxy-ester-containing biodiesel fuel with one or more reactants to produce an enhanced biodiesel fuel composition comprising functionalized ester species, wherein such enhancement of the biodiesel fuel at least partially results from an improvement in the low-temperature properties of said enhanced biodiesel fuel relative to those of the biodiesel fuel from which it was derived, wherein the unsaturated ester molecules are selected from species having the general formula: wherein R 1 , is selected from the group consisting of C1 to C3 alkyl moieties; and wherein R 2 and R 3 are independently selected from the group consisting of C1 to C10 alkyl moieties, C1 to C10 alkenyl moieties, and combinations thereof, and wherein the step of reacting the epoxy-ester species comprises a direct esterification of at least some of the epoxy-ester species.