Gamma radiolysis of a heavy petroleum fraction

A relatively heavy petroleum fraction called distillate arom. ext. (DAE) which has been proposed to be the carrier of the emission bands of certain astronomical objects like proto-planetary nebulae (PPNe) and the so-called unidentified IR bands (UIBs), has been radiolyzed with g-radiation to a total dose of 1 MGy. The stability of DAE toward radiation was assessed by FT-IR and electronic spectroscopy. The gases produced during radiolysis have been identified by GC. They were essentially H2 and CH4. A certain degree of crosslinking has been verified on the radiation-processed material by measuring the hexane insol. fraction of DAE, which increased dramatically after the radiation treatment. Further analyses were conducted using high performance liq. chromatog. (HPLC) on the radiation processed sample in comparison to the pristine sample.