The permitted alcohol content of bioethanol-blended gasoline (bio-gasoline) is set under the Act on the Quality Control of Gasoline and Other Fuels. This is required because methanol(CAS 67-56-1) can cause corrosion and deterioration of machine components, leading to fuel leaks and other problems. ASTM D4806 is the quality standard for bioethanol. It prescribes GC quantitation for the concentrations of ethanol and methanol (specified by ASTM D5501). However, the ASTM D5501 method uses a 100 m or 150 m column, resulting in long analysis times.
Fast analysis of bio-ethanol using a heart-cut system is demonstrated below.
Analysis according to ASTM D5501
Analysis using heart-cut (FID)
With a 150m column, this analysis takes over 40 minutes.
The heart-cut system separates ethanol (EtOH, CAS 64-17-5) and methanol (MeOH) from other hydrocarbons in the 1st column (Rtx-1), and then conducts more precise separation in the 2nd column (Rtx-Wax). The analysis time for the 2nd column is significantly shorter than the ASTM D5501 method. The quantitation performance is approximately equivalent to ASTM D5501. This shows that the heart-cut system can rapidly and accurately quantify the alcohol concentration in bio-ethanol.