INTERFACIAL PROPERTIES OF THE PRODUCTS OF OZONOLYSIS OF HAMACA CRUDE OIL

Abstract

A sample of extra-heavy Hamaca crude oil, dissolved in carbon tetrachloride, was oxidated with ozone for a few minutes. The reaction mixture was washed with a concentrated solution of HCl, neutralized with sodium carbonate, and the products were extracted from the aqueous phase. The products were characterized by using gel permeation chromatography (GPC), elemental analysis, 1H nuclear magnetic resonance (NMR), and Fourier transformed infrared (FTIR) techniques. The results of the analyses show that the products have lower molecular weights, lower aromatic character, and higher oxygen content than the original sample. They also indicated that these products were mainly carboxylic acids, aldehydes, and/or ketones, with a higher affinity for water than for carbon tetrachloride, the organic solvent that was used. Interfacial tension γ measurements (water–toluene) performed with these products showed a linear dependence with concentration, where γ dropped from 32 to about 7.7 dinas/cm at the apparent critical Micelle concentration (cmc) (2 g/L). Larger quantities of a commercial sample of nonylphenol ethoxylated were needed for an equivalent γ drop. In another experiment the above oxidated product was mixed with Furrial asphaltene in toluene, and γ measurements were performed as above and compared with the values obtained for the same experiment using the ethoxylated surfactant. In this case, the γ values for the oxidated product were higher, suggesting a better adsorption on the asphaltene colloids. These preliminary results suggest that these oxidated products could be employed as general surfactants in the oil industry.