▎ 摘　　要

NOVELTY - Biodiesel is formed by adding 5-25 vol.% pour point depressant to 75-95 vol.% mixed diesel formed by mixing 10-50% gutter oil biodiesel and 50-90% mineral diesel, and mixing. The gutter oil biodiesel is produced by transesterifying gutter oil and methanol in presence of graphene oxide at 70 degrees C for 2 hours, aging reaction solution for stratification, evaporating supernatant at 70 degrees C, washing residue with water to remove water-soluble substance, adding anhydrous calcium chloride to washed residue, stirring, aging for 30 minutes, and filtering to remove calcium chloride. USE - Biodiesel is used for bus. ADVANTAGE - The biodiesel has favorable cold filter plugging point, pour point, cloud point, flash point, kinematic viscosity, oxidation stability, calorific value, density and acid value. DETAILED DESCRIPTION - Biodiesel is formed by adding 5-25 vol.% pour point depressant to 75-95 vol.% mixed diesel formed by mixing 10-50% gutter oil biodiesel and 50-90% mineral 0# diesel, and mixing. The gutter oil biodiesel is produced by transesterifying gutter oil and methanol in presence of graphene oxide at 70 degrees C for 2 hours, aging reaction solution for stratification, evaporating supernatant at 70 degrees C in a rotary evaporator, washing residue with water to remove water-soluble substance, adding anhydrous calcium chloride to washed residue, stirring, aging for 30 minutes, and filtering to remove calcium chloride. The molar ratio of methanol and gutter oil is 6-8:1. The mass ratio of graphene oxide and gutter oil is 1.5-3:100. The pour point depressant is prepared by ultrasonically mixing isodecyl methacrylate and isooctyl methacrylate in volume ratio of 1:0.25-0.5, or ultrasonically mixing isodecyl methacrylate and ethyl acetoacetate in volume ratio of 1:0.25-4. An INDEPENDENT CLAIM is included for preparation of biodiesel.