Application ADU 5: Ethanol Containing Gasoline

E50 is an important temperature point in gasoline specification. Gasoline oxygenate blends with higher ethanol content show an azeotropic effect which has significant influence on the temperature slope and have special requirements for heater control.


ASTM D86 is applicable to ethanol-fuel blends with greater than 10 % ethanol content. This was concluded after conducting an interlaboratory study with 15 different samples containing different percentage of ethanol.

Better Performance

By using the heater control mode for ethanol containing gasoline the performance of ADU 5 can be significantly improved for the distillation rate of ethanol containing gasolines with an ethanol content between 10 % and 20 %.
While there is a characteristic drop in distillation rate at about 50 % in fuel mode, this drop does not occur anymore when using the ethanol containing gasoline heater controlling mode.

Fig. 1: Distillation rate in heater mode “Fuel”

Fig. 2: Distillation rate in heater mode “Ethanol containing gasoline”

Program and Initial Heater Parameters to Be Applied:

Copy program ASTM D86 Group 1 or ISO 3405 Group 1

Quick settings:
Initial heating 1: 150 °C
Time for initial heating 1: 220 s
Initial heating 2: 430 °C
Final heat adjustment: 5 %

Fig. 3: Automatic Distillation Unit ADU 5


106358 Distillation flask, 125 mL
106619 Stopper for flask side arm
106612 Measuring cylinder, 100 mL
106310 Heater board, Ø 38 mm
106620 Drip plate
106219 Boiling stones (porous)

Do you have any questions?

Contact Anton Paar ProveTec directly: support.provetec[at]

Learn more about the ADU 5