저분자량 PS 공중합체를 이용한 중유 속 아스팔텐의 분산성 향상

Abstract

ABSTRACT

Enhancenment of the dispersion of asphaltenes in heavy oil using low MW PS copolymers

Jo, Myong Guen Advisor: Prof. Kim, Joon-Seop, Ph.D. Department of Energy Convergence, Graduate School of Chosun University

In this work, the dispersion degrees of asphaltenes in heavy oil were containing polystyrene based acidic copolymers and their ionomers were investigated. As the first part of the study, we studied the effects of the addition of sulfonated polystyrene copolymers and their ionomer forms on the dispersion of the asphaltenes in a oil. It was found that the acid forms of sulfonated polystyrene interacted with the asphaltene and, thus, enhanced the precipitation of the asphaltenes in the oil. On the other hand, in the case of the sulfonated ionomers, neutralized with Na, they increased the precipitation and dispersion abilities of the asphaltenes when the ion content was low and high, respectively. At low ion content, the distance between ion pairs on the same polymer chain was relatively too long to form ionic aggregates with next ions on the chain. In this case, the ion pair mainly interacted with asphaltenes, which enhanced the asphaltenes precipitation. At high ion content, however, the ion pairs of the ionomer on the same polymer chain could form loose ionic aggregates, which acted as particles that existed between asphaltenes. Then, the asphaltenes could not interact with each other, and, thus, could not form aggregates. In the case of amine-neutralized ionomers, they did not affected the dispersion behavior of the asphaltenes strongly because the strength of ion interactions was too weak for the ionomers to act as effective ionomers. As the second part of the study, we used styrene-methacrylate ionomers as dispersants. It was observed that acid form copolymers of low-MW increased the dispersion property of asphaltenes with increasing acid contents. However, the high-MW copolymers did not change the property significantly. For the ionomers, it was found that the addition of the ionomers enhanced the asphaltene dispersion; the higher the ion content was, the stronger the effects was. Lastly, it was concluded that the methacrylate ionomers were better for the asphaltene dispersion that the sulfonate ionomers because the strength of the interactions between ion pairs was weaker for the methacrylate ionomers than the sulfonate ionomers.