Quantification of ethanol in petrol–ethanol blends: Use of Reichardtʹs ET(30) dye in introducing a petrol batch independent calibration procedure

Petroleum fuels are generally non-polar. The presence of ethanol in the petrol–ethanol fuel blends increases the polarity of the fuel blend. It was observed that absorption spectral shift of the Reichardtʹs ET(30) dye is sensitive to the petrol–ethanol blend polarity. It was also found that ET(30) dye has a characteristic λmax of absorption in petrol–ethanol blends irrespective of the petrol batch with which blends were prepared. In the present work, a sensitive analytical method for the petrol batch independent quantification of ethanol content in petrol–ethanol blends has been developed.