固相萃取采样和气相色谱-质谱检测液化石油气中的芳烃杂质（英文）

Investigation of aromatic impurities in liquefied petroleum gas by solid-phase extraction sampling coupled with gas chromatography-mass spectrometry

建立石墨化碳(GCB)为吸附剂的动态采样系统,可实现液化石油气(LPG)中芳烃杂质的采样和同步萃取富集。LPG中的芳烃杂质(苯、甲苯、二甲苯、苯乙烯和萘)被快速捕集后,进行气相色谱-质谱(GC-MS)定性定量分析。与C18和苯乙烯二乙烯苯吸附剂(PS-DVB)相比,GCB填充柱对芳烃杂质的萃取效率最高。评价了基于GCB填充柱采样的吸附效率、重现性和贮存稳定性。采样和分析方法对氮气模拟气流中8种芳烃的定量分析线性范围为15~1 000μg/m^3。所开发的方法具有回收率高(92.9%~109.0%)、检出限低(1.0~6.2μg/m^3)、准确性好(相对标准偏差为0.6%~5.8%)和准确度高(标准偏差为0.8%~8.2%)等优点。

A dynamic solid-phase extraction system for sampling and synchronous preconcentration of aromatic impurities from liquefied petroleum gas（LPG）with graphitized carbon black（GCB）sorbents was constructed.The target aromatics（benzene,toluene,xylenes,styrene and naphthalene）were rapidly collected from LPG flow and analyzed with gas chromatography-mass spectrometry. Compared with C18 and poly（styrene-divinylbenzene）copolymer sorbents,the tandem packed GCB cartridges presented the highest extraction efficiency for capturing aromatics from LPG. The sampling efficiency,reproducibility and storage stability of aromatics on the adsorption GCB cartridge were evaluated. The quantification curves of eight aromatics in nitrogen simulative gas flow were linear in the range of 15-1 000 μg / m^3. The developed sampling method presented good advantages of high recoveries（92. 9%-109. 0%）,low method detection limits（1. 0- 6. 2 μg / m^3）,together with excellent precision（relative standard deviations：0. 6%- 5. 8%） and accuracy（relative errors：0. 8%- 8. 2%）,respectively.