The specialized gas chromatograph for analyzing benzene and toluene in refined automotive and aviation gasoline is suitable for determining the content of benzene and toluene in automotive and aviation gasoline. The range of benzene content determination is 0.1%~5% (volume fraction), and the toluene content is 2%~20% (volume fraction).
The ether compounds such as methyl tert butyl ether added to finished gasoline do not interfere with the determination of benzene and toluene. When using 1,2,3-tris (2-cyanoethoxy) propane (TCEP) packed column as the analytical column, it is not suitable for gasoline containing ethanol, and methanol may also cause interference. When using a modified polyethylene glycol (FFAP) capillary analysis column, the interference of methanol and ethanol is not significant.
This instrument fully complies with the ASTM D3606 method standard, with a simple system, easy operation, low investment cost, and easy maintenance; However, it is not suitable for determining the total aromatic hydrocarbon content in gasoline, nor is it suitable for determining the benzene content in ethanol gasoline.





Standard sample chart:

working principle
The dedicated gas chromatography analysis system for benzene and toluene in refined automotive and aviation gasoline consists of a six way valve, a pre column, and an analysis column. Pre column is a chromatographic column filled with a non-polar stationary phase (methyl silicone), which utilizes its characteristic of separating sample components in boiling point order to achieve pre separation of benzene and toluene from heavy hydrocarbons; The analytical column is a chromatographic column filled with a strongly polar stationary phase of 1,2,3-tris (2-cyanoethoxy) propane (TCEP) or modified polyethylene glycol (FFAP), mainly used for separating aromatic hydrocarbons and non aromatic compounds smaller than octane. The method uses thermal conductivity detector or hydrogen flame ionization detector for measurement and internal standard method for quantification. During analysis, butanone (MEK) is first added to the sample as an internal standard, and then introduced into the pre column. After the octane in the sample flows out of the pre column and enters the analysis column, the six way valve is placed in the blowback state. On the analysis column, the octane and light components are completely separated and detected by the detector. The peak area is measured, and the concentration of each component is calculated based on the internal standard.

Instrument system configuration
1. Gas chromatograph (FID detection, automatic blowback switching of ten way valve or six way valve)
2. Chromatographic column:
Pre cut column: Column length 1.0m, outer diameter 3.2mm, inner diameter 2.2mm, 10% methyl silicone (mass fraction)/60-80 mesh white silane carrier
Analysis column: column length 4.6m, outer diameter 3.0mm, inner diameter 2.0mm, TCEP， 15% or 20% (mass fraction)/Chromosorb P 80-100 mesh [or elastic quartz capillary FFAP 50m × 0.25mm]
3. Computer Workstation
4. Chromatographic gas source (high-purity nitrogen, high-purity hydrogen, pure dry air)
5. Standard samples
System cutting standard sample
Qualitative standard samples of benzene and toluene
Calibration standards for benzene and toluene
Internal standard substance butanone (MEK)