The naphtha fraction of the pyrolytic oil was objected to gc analysis . the above - middle fraction underwent gc analysis too after chemical class separation . the chemical composition of the pyrolytic oil was clearly known this way 对轻质石脑油馏分做了气相色谱分析，对中质以上馏分在族分分析的基础上也对饱和烃和芳烃族分进行了气相色谱分析。
