TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The weight ratio of the component (b) to the component (a) is 0.01-100:1, preferably 0.05-10:1.The aromatic amine type antioxidant is substituted naphthylamine, substituted diphenylamine, substituted p-phenylene diamine or substituted quinoline, preferably chosen from 22 compounds e.g. N-phenylN'-cyclohexyl-p-phenylene diamine, N,N-(1,3-dimethyl butyl)N'-phenyl-p-phenylene diamine, N,N'-bis-(1,4-dimethyl pentyl)-p-phenylene diamine, N-p-tolylN'-(1,3-dimethyl butyl)-p-phenylene diamine and N,N'-diheptyl-p-phenylene diamine.The naphthylamine is phenyl alpha -naphthylamine, phenyl alpha -naphthylamine and/or N-para-methoxy phenyl alpha -naphthylamine. The substituted diphenylamine is 4-10C alkylated diphenylamine. The substituted quinoline is 6-ethoxy-2,2,4-trimethyl-1,2-dihydro quinoline, 6-phenyl-2,2,4-trimethyl-1,2-dihydro quinoline, 6-dodecyl-2,2,4-trimethyl-1,2-dihydro quinoline and/or 2,2,4-trimethyl-1,2-dihydro quinoline polymer.The polyamine is organic amine of formula: HN(R1)(R2) (I), H2NR3-NHR4 (II) or (R12)(R13)-N((CH2)x7-N(R14))y3((CH2)x8N(R15))y4R16 (III), polyether diamine of formula: H2N-CH(R5)-CH2(-OCH2-CH(R5))x1-NHR4 (IV), imidazoline type polyamine of formula (V), polyolefin polyamine of formula: H2N((CH2)x2NH)y1R6 (VI) and/or condensation compound of polyolefin polyamine and/or propylene oxide, piperazine type polyamine of formula (VII), piperidine type polyamine, polyamine containing t-amine of formula: (R9)(R10)-N(CH2)x4-NH2 (VIII), N((CH2)x5-NH2)3 (IX) or R11-N((CH2)x6-NH2)2 (X).R1, R2 = H, OH, 1-30C group optionally substituted by carbonyl, OH, carboxy, ester, acyl, alkoxy, nitro, cyano, halo or amino;R3 = 1-30C alkylene or polyether;R4 = 1-30C alkyl or polyether;R5 = H or methylR12 , R16, R6 = H or 1-30C alkyl;x7, x8 = 0-10;y3, y4 = 0-5;or R12 or R13+R14 or R15 = ring;x1 = 1-10;x2 = 2-4;y1 = 1-8;R7 = 1-24C alkyl;y2 = 0-5;R8 = H, 1-24C alkyl or (CH2)x3NH2;x3 = 0-5;R9, R10 = H or 1-24C alkyl;x4 = 0-10;x5 = 1-10;R11 = 1-24C alkyl; andx6 = 1-10, preferably 2-6.The amine of formula (II) is hexane diamine, N-coco-1,3-propylene diamine, N-oleyl-1,3-propylene diamine or N-tallow-1,3-propylene diamine.The polyolefin polyamine (VI) is ethylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pentamine, pentaethylene hexamine, hexaethylene heptamine, heptaethylene octoamine, propylene diamine, dipropylene triamine, tripropylene tetramine, tetrapropylene pentamine, pentapropylene hexamine, hexapropylene heptamine, heptapropylene octoamine or N,N'-bis(3-amino propyl)-ethylene diamine.The piperazine polyamine is N-(2-amino ethyl)piperazine or N,N'-bis(amino ethyl)piperazine.The piperidine type polyamine is 4-amino-2,2,6,6-tetramethyl piperidine or 1-(2-amino ethyl)piperidine.The polyamine containing t-amine is N,N-dimethyl-1,3-propylene diamine, N,N-diethyl-1,3-propylene diamine, N,N-dibutyl-1,3-propylene diamine, N,N-dimethyl-1,3-butyl diamine, N,N-diethyl-1,3-butane diamine, N,N-dimethyl-1,6-hexane diamine, tris(2-amino ethyl)amine or N,N-bis(3-amino propyl)methylamine.The polyamine derivatives are products of aminolysis reaction of 6-40C organic acid, 6-40C acyl halide or 6-40C organic acid alkyl ester and polyamine, or products of aminolysis reaction of 6-40C fatty acid, 6-40C aliphatic acyl halide or 6-40C fatty acid alkyl ester and polyamine.The fatty acid is caproic acid, hexane diacid, octanoic acid, isooctanoic acid, decanoic acid, dodecoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, oleic acid, linoleic acid, linolenic acid, ricinolic acid, eicosenoic acid, eicosanoic acid, erucic acid, docosenoic acid, dimer of oleic acid and/or linoleic acid, oleic acid, linoleic acid, linolenic acid, industrial dimer acid, soybean oil acid, peanut oil acid, colza oil acid, ricinoleic acid and tall oil acid.The aliphatic acyl halide is acyl halides of the above fatty acids.The fatty acid alkyl ester is 1-5C alkyl esters of the above fatty acids. The polyamine derivatives are the products of condensation reaction of polyamine and 1-6C aldehyde. The molar ratio of total amount of polyamine to 1-6C aldehyde is 1:(0.1-10) and the reaction temperature is 80-150 degrees C. The 1-6C aldehyde is formaldehyde, acetaldehyde, propionic aldehyde, cyclohexanal or their aqueous solutions.Alternately, the polyamine derivatives are products of aminolysis reaction between acylating agent containing two acyl groups and the above polyamine in the molar ratio of 1:(0.5-2). The acylating agent is organic binary carboxylic acid, anhydride and semi-ester substituted by 6-30C alkyl, preferably maleic acid, succinic acid, fumaric acid, itaconic acid, citraconic acid, isatoic acid, phthalic acid, maleic anhydride, succinic anhydride, itaconic anhydride, citraconic anhydride, isatoic anhydride and phthalic anhydride substituted by 6-30C alkyl, preferably chosen from 30 compounds e.g. nonyl succinic acid, decyl succinic acid, dodecyl succinic acid, tridecyl succinic acid and tetradecyl succinic acid.The composition further contains metal deactivator which can react with metal surfaces and/or metal chelating agent which can react or combine with metal or metal ions, preferably chosen from benzotriazole, ammonium salts formed by benzotriazole and aliphatic amine, products obtained from benzotriazole, formaldehyde and aliphatic amine through Mannich reaction, Schiff's base and organic polybasic carboxylic acid. The Schiff's base is N,N'-bis(salicylidene)-1,2-propylene diamine and the organic polybasic carboxylic acid is tartaric acid.The content of the additive composition with respect to the base diesel oil is 50-10000 ppm.The base diesel also contains other diesels chosen from petroleum diesel, Fischer-Tropsch synthesis diesel, hydrocracking diesel and oxygen- containing diesel blends. The volume ratio of the biodiesel to other diesel is 1:0-99.