Synthesis And Evaluation Of Fuel Anti-Static Additives

Hydrocarbon fuels are normally very poor conductors of electricity. Electrical charges, therefore, tend to accumulate in preservation and transportation. Dangerous accumulation of electrostatic charge can be preventing by raising the electrical conductivity of the fuel and this can be achieved by using anti-static additives. Two kinds of ashless anti-static additives were synthesized and their performance were also been evaluated.Polysulfone was prepared withα-alkenes and SO₂, and the effects of reaction conditions including sorts of initiating agent, the ratio ofα-alkenes to SO₂,α-alkenes to solvent, reaction temperature and time on the yield and the performance of product were investigated. The results showed that paraldehyde and hydrogen peroxide is an effective initiating agent to the reaction, using benzene and toluene as solvent, dodecyl mercaptan as molecular weight regulator. The alkene could be totally reacted to polysulfone when the mol ratio ofα-alkenes to paraldehyde, the paraldehyde to hydrogen peroxide, the amount of dodecyl mercaptan to the alkene, the mol ratio ofα-alkenes to SO₂ and reaction time were 20:9, 20:1, 1:400, 1:4, 9～15hrs at room temperature, respectively. The polysulfone were characterized by infrared spectroscopy and elemental analysis, and the result showed that the absorption peak of functional group of sulphone was obviously and elementary composition of the polysulfone was coincident with the calculated value.Polyamine was synthesized with epichlorohydrin and aliphatic primary amine as anti-static additive for fuel. Non-aqueous titration with perchloric acid was used to determine the value of tertiary amine in the polyamine. The results showed that the conversion ratio of octadecylamine was achieved 97%, while the mol ratio of epichlorohydrin to octadecylamine was 2:1 and half of the octadecylamine was added to the epichlorohydrin and reacted for 4h at 55-60℃, and the other half was added and reacted for 4hr at 80℃, and then the temperature of the mixtures was raised to 90℃, sodium hydroxide was added twice, the reaction time were 12h respectively. The tertiary amine and ammonium salt in the intermediate compounds were titrated by acid and the mechanism was discussed.The composite of polysulfone and polyamine was studied and was highly effective in improving the conductivity of fuels. The results showed that the conductivity of diesel fuel was increased by 239 ps·m^-1 when the mass ratio of polysulfone to polyamine and the dosage were 1:1 and 2mg·L^-1, respectively. The conductivity of diesel fuel was incremental with storage time, and increased by 664ps.m^-1 after 7 days.