Isolating pitch oligomers by continuous, countercurrent, dense-gas extraction-Part II. Mesophase pitches of narrow molecular weight

摘要

Petroleum pitches are carbonaceous materials that can serve as precursors for high performance/high thermal conductivity carbon fibers. They are complex mixtures of alkylated polycyclic aromatic hydrocarbons (PAHs) with molecular weight ranging from 200 to over 1000 Da and are obtained by the thermal polymerization of aromatic decant oil, a byproduct of the fluid catalytic cracking (FCC) of the heavy gas oil fraction of crude oil. Mesophase pitch-based carbon fibers, i.e., those processed from anisotropic liquid-crystalline pitches, present attractive properties such as high thermal conductivity (up to four times that of copper), low density and low coefficient of thermal expansion , for thermal management applications where thermal stresses must be minimized and excess heat needs to be efficiently removed: examples include microelectronic packaging, semiconductor modules and hybrid cars. In this work, our dense-gas extraction (DGE) process is investigated for producing mesophase pitches for advanced carbon application from a petroleum pitch (M-50, from Marathon Petroleum Company LLC).