超临界流体分级萃取正构烷烃和多环芳烃

Study on Supercritical Fluid Fractional Extraction of n Alkanes and Polycyclic Aromatic Hydrocarbons in Environmental Spiked Samples

本工作用超临界ＣＯ２对环境模拟样品中的正构烷烃和多环芳烃的超临界分级萃取方法及超临界ＣＯ２的压力，温度和用量对分级效率的影响进行了详细的研究。结果表明，在低压、低温下（８０ＭＰａ，５０℃）能成功地分级萃取正构烷烃和多环芳烃，其Ｃ１０～Ｃ１８的萃取率为９９．９４％～５９．２８％，而多环芳烃基本未被萃取。当压力升至２６．０ＭＰａ、温度升至８０℃时，可有效地萃取多环芳烃。

Fluid fractional extraction of n alkanes and polycyclic aromatic hydrocarbons(PAHs) in environmental spiked samples were carefully and systemaicatlly studied using CO 2 as supercritical fluid.The effects of pressure,temperature and volume of CO 2 on the fractional efficicy were investigated.Results indicated that n alkanes and PAHs can be extracted successfully under condition of lower pressure and temperature (8 0 MPa,50℃) with a recovery range of 99 94% to 59 28% for n C 10 to C 18 ,and almost no PAHs are extracted.Under pressure of 26 0 MPa and temperature of 80℃ PAHs can be effectively extracted.