采用1,2,3-三-(2-氰基乙氧基)丙烷(简称TCEP)微填充柱(56 cm×1.6 mm)和HP-1石英毛细管柱(30 m×0.53 mm,0.5 μm)及带有十通阀系统的气相色谱仪,自动进样器进样,外标法定量.样品在TCEP微填充柱中得到初步分离后,并用火焰离子化检测器(FID B)检测,放空先于甲醇和苯流出的组分,然后切换十通阀,将还未从TCEP微填充柱中流出的组分反吹到HP-1毛细管柱中分离并用FID A检测 .汽油样品无需预处理直接一次进样同时测定车用汽油中甲醇和苯含量.甲醇及苯的峰面积与相应的浓度之间在50.0 g·L-1及100.0 g·L-1以内呈线性关系,甲醇的检出限为0.5 g·L-1,回收率为93.3%;苯的检出限为0.02 g·L-1,回收率为97.0%.

In the GC determination of methanol and benzene in car-gasoline,a micro column (56 cm×1.6 mm) packed with 1,2,3-tris-(2-cyanoethoxy)-propane (abbreviated as TCEP),and a HP-1 capillary column (30 m×0.53 mm,0.5 μm) were used in combination for the separation of various components in the gasoline sample.One μL of sample was introduced by the automatic sample injector.A preliminary separation was done in the TCEP microcolumn,and detections were made by FID B.Components coming out before methanol and benzene were let out to air.Components remaining in the TCEP microcolumn were blown to the capillary column by changing the 10-way valve,to be separated further and detected by FID A.Methanol and benzene of the sample were determined simultaneously by using the external standard method.Linear relationship between values of peak area and concentration of methanol and of benzene were obtained in the ranges within 50.0 g·L-1 and 100.0 g·L-1 respectively.Detection limits (3S/N) found were 0.5 g·L-1 for methanol and 0.02 g·L-1 for benzene.Recovery of the method was tested and values found were 93.3% for methanol and 97.0% for benzene.