Oxidation of several liquid, long chain hydrocarbons (alkanes, alkenes, are
nes, and a light gas oil, LCGO, product of a coking process) has been studi
ed by using a low-pressure high-voltage oxygen plasma. Olefins were readily
oxidized to epoxides and carbonyl compounds, O(P-3) being the active speci
es in the plasma. At long treatment times the saturated chains of the olefi
ns also reacted to produce secondary alcohols and ketones. These compounds
and tertiary alcohols, only when tertiary carbons were present, were obtain
ed with alkanes. At 5 min 4-phenyl-1-butene showed reaction mostly on the o
lefinic C=C, followed by oxidation of the aromatic ring. At 120 min the ole
finic fraction oft;he compound was eliminated and the reaction of the satur
ated -CH2-groups represented only 0.6% of the total conversion. LCGO, with
a composition of 65.1% alkanes, 34.8% aromatics, and 3.1% olefins, was trea
ted under similar conditions used for the model compounds. At 120 min the o
lefinic fraction of the mixture was eliminated and the cetane number, a par
ameter indicating the quality of fuel oils, was improved by 66% without any
additional treatment.