Effects of Styrene Ionomers on the Dispersion of Asphaltenes in Crude Heavy Oil

Abstract

The purpose of this work was to investigate the effects of polystyrene-based acidic copolymers and ionomers on the dispersion of asphaltenes in heavy oil. In the first part of the work, we studied the effect of the addition of sulfonated polystyrene acidic copolymers (SSA) and Na-neutralized ionomers (SSNa) on asphaltene dispersion. It was found that the SSA copolymers and the low ion content SSNa ionomers did not show asphaltene dispersion enhancement. However, high ion content SSNa ionomers improved asphaltene dispersion. In the second part of the work, styrene–methacrylate ionomers (SMANa) were used as dispersants. It was observed that the SMANa ionomers improved asphaltene dispersion significantly as the ion content increased and the molecular weight of the SMANa ionomer decreased. Finally, it was found that asphaltene dispersion was more effective when SMANa ionomers were used as asphaltene dispersants, compared to SSNa ionomers. Therefore, it can be concluded that to improve asphaltene dispersion, the acidic copolymers must first be converted to ionomers by neutralization. In addition, when using the ionomer as an asphaltene dispersant, it should be noted that the type of ionic group of the ionomer was more important to control asphaltene dispersion than the MW of the ionomer.

Review on Applications of Ionic Liquids (ILs) for Bitumen Recovery: Mechanisms, Challenges, and Perspectives

“…30 The presence of the heteroatoms as well as the organometallic constituents (Ni, V, and Fe) is known to be responsible for association and aggregation of asphaltene molecules in crude oil. 66,68,69 The viscosity of heavy oil can be efficiently reduced through dissolution or dispersion of asphaltene, 10,23,30,37,68,74,93,94 which consequently improves oil recovery. 7,30,34,65,66 Although the concept has been researched using flowable heavy oils, 96 with the exception of very few ones on the extra-heavy oil (bitumen), 37 the ability of certain imidazolium ILs to disperse asphaltene and/or solubilize the highly viscous oils have been widely reported.…”

“…66,68,69 The viscosity of heavy oil can be efficiently reduced through dissolution or dispersion of asphaltene, 10,23,30,37,68,74,93,94 which consequently improves oil recovery. 7,30,34,65,66 Although the concept has been researched using flowable heavy oils, 96 with the exception of very few ones on the extra-heavy oil (bitumen), 37 the ability of certain imidazolium ILs to disperse asphaltene and/or solubilize the highly viscous oils have been widely reported. 30,37,72,93,94,10,23,30,37,74,93,94 Aside from the IL−clay interactions, electrostatic interactions may possibly occur between the ILs and oil components such as asphaltene, depending on the properties of the ILs.…”

“…Essentially, the acidic ILs due to their charge and polarity have the tendency to form hydrogen bonds and π−π interactions with asphaltene aggregates, which subsequently enhance asphaltene dispersion. 66,71 Accordingly, as shown in Figure 15, Sakthivel et al 72 presented a mechanism representing the interaction of the ionic liquids with the asphaltene and other components such as resin and aromatics. The authors 72 attributed the IL action to mechanistic fortification of "force of interaction" with the asphaltene and resin components.…”

Inhibition of Asphaltene Precipitation by Ionic Liquid Polymers Containing Imidazole Pendants and Alkyl Branches

“…However, for asphaltene with high polarity, the effect of existing polymers will be reduced, so the polar groups of polymers need to be modified to enhance the interactions with asphaltene accordingly. Polymers containing ions were also applied as asphaltene inhibitors . The styrene ionomers (SSNa) and styrene-methacrylic acid ionomers (SMANa) were synthesized as asphaltene dispersants.…”

“…Polymers containing ions were also applied as asphaltene inhibitors. 26 The styrene ionomers (SSNa) and styrene-methacrylic acid ionomers (SMANa) were synthesized as asphaltene dispersants. It is found that the SMANa ionomer is more effective than the SSNa ionomer.…”