Biodiesel Titration Using
Phenolphthalein or Turmeric



Search this site!

Once you get the hang of it, biodiesel titration is fast and easy. It should take between 10 and 15 minutes.

Supplies for biodiesel titration



What You Will Need:

Titration Solution

• 3 small disposable containers, plastic or glass that will hold about 1/4 cup

• Isopropyl alchohol 91% or better (Iso-HEET can be purchased from an automotive store)

• Waste vegetable oil, needs to be filtered and de-watered • Phenolphthalein (or tumeric - see bottom of page or instructions)

• 3 syringes with 1 ml increments that hold 10 ml

• safety goggles

• safety gloves





Instructions for Biodiesel Titration:

Containers Labeled for Biodiesel Titration

Label your small containers 'Titration,' 'Isopropyl,' and 'Titration Solution'.

Label the syringes with 'Titration solution,' 'Alchohol,' and 'Oil'.

making a biodiesel titration

Pour enough isopropyl alchohol, and oil into the corresponding cups to allow you to easily suck it up with a syringe.

Measuring 10 ml isopropyl alcohol for titration

With the syringe measure 10 ml of isopropyl alchohol and put it in the 'titration' container.

With the other syringe measure 1 ml of oil and add it to the 'titration' cup as well.

Use a swirling motion to mix the contents of the 'titration' cup.

Adding Phenolphthalein to Titration

Put 4 drops of Phenolphthalein into the 'titration' cup and give it a few more swirls. (if using Turmeric, see ** below).

Put 10 ml of titration solution in the appropriate syringe. (You will not use the entirety of this - it will slowly be added until the pH indicator indicates it is enough).

Adding Titration Solution to Titration

Add a drop at a time of the titration solution from the syringe into the 'titration' cup. Continue mixing it by swirling the cup and watch for it to change color. When the mixture turns pink and stays that way for 30 seconds, stop.

Finished Titration

When finished, it should look about like this.

Calculate how much titration solution was added by subtracting what is remaining from 10 ml that was previously in the syringe.

Now perform titration two more times and average the results!

Finish up with this Biodiesel Titration Formula>>>




** If Using Turmeric as Your pH Indicator:

• Add enough turmeric to the titration cup to give it a pale yellow, then while adding the titration solution, wait till it turns a dark red and holds that color for 20 seconds.


Back to 'Titration Introduction'

Back to Biodiesel Homepage