Producing Hexane-Insoluble Asphaltene Films from Coal Pitch

Abstract

The possibility of producing hexane-insoluble asphaltenes from a toluene solution of mid-temperature coal pitch is demonstrated. The topography, morphology, and structure of films consisting of asphaltene associates are studied by scanning and transmission electron microscopy. The thermal decomposition of hexane-insoluble asphaltenes is investigated in the range 20–800°C. Structuring of the film is observed at 495°C, regardless of the method employed: X-ray phase analysis or differential calorimetry. According to IR spectroscopic data, films heat-treated at 500°C contain graphene-like structures. X-ray diffraction shows the formation of graphene-like structures on heating the films to 800°C.