Asphaltene, the cheapest fraction of petroleum, was modified into a novel additive in order to facilitate a deasphalting process, such as paraffinic froth treatment. Asphaltene powder was oxidized by ozone, which is more powerful and less harmful to the environment than other oxidants. The ozonized asphaltene was characterized, and the reaction kinetics of ozonation was interpreted by the shrinking core model. Ozonized asphaltene was added to a water/n-pentane/bitumen emulsion to enhance the precipitation of asphaltene. Control of the properties of the precipitate was allowed by adjusting the ozonation degree and dosage of ozonized asphaltene. The removal of asphaltene was enhanced from 40% to a maximum of 70% by adding ozonized asphaltene under the same conditions. The boiling point distribution of deasphaltened oil indicates that a large amount of residue was removed using ozonized asphaltene. The dispersion behavior was checked by measuring the aggregate size in toluene and alkane solution. It was confirmed that asphaltene and ozonized asphaltene can interact with each other with high affinity.

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Heavy oil/bitumen with asphaltene requires high energy consumption for transportation, because of its high viscosity. This often causes serious pipeline problems; therefore, it is necessary to reduce the viscosity to resolve these issues. In this paper, we propose a new simple method to reduce the viscosity of diluted bitumen using partially oxidized asphaltene without removing asphaltene. This partially oxidized asphaltene, modified by exposing asphaltene to ozone, has a strong affinity to nonoxidized asphaltene via π−π stacking, hydrogen bonding, and acid−base interaction. The added oxidized asphaltene thus facilitated the agglomeration of asphaltene, so that the hydrophilic part can be hidden, and a small amount (1250 ppm) decreased the viscosity of diluted bitumen by up to 45%. We investigated the change in rheological properties of the diluted bitumen for various oxidized fractions of asphaltene and for various fractions of oxidized asphaltene to asphaltene. We showed that the decreased shear viscosity is likely to originate with the increased particle size of the asphaltene, that is, not the change in interactions between the asphaltene particles, but rather from their nonuniform distribution in size.

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