Study On The Synthesis And Properties Of A Series Of Heptadecyl-Dimethylpheny-Sulfonates

The object of the dissertation were to synthesize a series of high purified mono-isomeric heptadecyl-dimethylphenyl-sulfonates, and find out the basic rule of relationship between molecular structure and performance of this kind of surfactants by investigating their properties, the optimal values which can produce ultra-low interfacial tension between oil and water were observed .According to the experimental datas, a series of flooding agent systems that having more potential applied value were determined .Twelve kinds of isomers of heptadecyl-dimethylpheny-sulfonates were synthesized from acyl chloride, xylene and halogenated hydrocarbons by means of molecular designing in this paper. The synthesized process concluded Friedel-Crafts reaction, Grignard reaction,catalyzed hydrogenation, sulfonation and neutralization. The structures of products and intermediates were identified by FT-IR, 1HNMR, 13C NMR.Surface properties of these heptadecyl-dimethylpheny-sulfonates solution were measured by the drop volume method, and the surface tension-concentration logarithmic curve was depicted, the parameters (cmc,γcmc) of these sulfonates were measured. The results show that, for the sulfonate isomers, accorrding to the aromatic ring shifted from the edge to the middle of the long carbonic chain, the cmc increased,⊿G0ad decreased,γcmc decreased,Γmax decreased, Amin increasedand pC20 increased. For the heptadecyl-dimethylpheny-sulfonates of single structure, as the temperature increased, cmc increased,⊿G0ad decreased,γcmc decreased,Γmax decreased, Amin increased, pC20 increased; As the concentration of electrolyte increased, cmc decreased,⊿G0addecreased,γcmc decreased,Γmax increased, Amin decreased, pC20 increased. The interfacial behavior between heptadecyl-dimethylpheny-sulfonates and n-alkaline or crude oil was measured by the Model 500 spinning drop interfacial tensionmeter. The influencial factors such as the heptadecyl-dimethylpheny-sulfonates, salt, alcohol and alkali on interfacial tension of the complex system were researched, the optimal values of different complex systerms which can produce ultra-low interfacial tension between oil and water were obtained, as well as the nmin values of different sulfonate isomers. According to the experimental datas, the different efficiency of the alkylbenzene sulfonate isomers of the odd carbon number reducing interfacial tension between oil and water under the same conditions were illustrated theoretically, and the role that the other components of the compounds play in reducing the interfacial tension between oil and water was also indicated.The foaming properties of heptadecyl-dimethylpheny-sulfonates were studied by improved Ross-Miles method. The results showed that, for the sulfonate isomers, as the aromatic ring shifted from the edge to the middle of the long carbonic chain, the foaming properties of these surfactants became increasing, and the foam stability increased. For the heptadecyl-dimethylpheny-sulfonates of single structure, as the temperature increased, the foaming power increased, but the foam stability.decreased. As the concentration of electrolyte increased in the sulfonates solution, the foaming power got worse.The adsorption properties of heptadecyl-dimethylpheny-sulfonates in the Daqing oil sands were measured by two-phase titration method, and the study showed that at 45℃, the liquid-solid ratio was 10:1, for 24 hours, adsorption of heptadecyl- dimethylpheny-sulfonates in the oil sands could reach equilibrium. Heptadecyl-dimethylpheny-sulfonates structures and concentration, the temperature, electrolyte and alkaline, alcohol would have direct impact on static equilibrium adsorption capacity of heptadecyl-dimethylpheny-sulfonates in the oil sands .