BioDiesel-Titrating

Titrating Oil To Make Biodiesel
INTRODUCTION
Why Do A Titration?  Titration is just a fancy word for the process used to find out how much catalyst will be needed to make biodiesel out of waste vegetable oil. The catalyst used is called Potassium Hydroxide (KOH), also known as Caustic Potash. You can also substitute Sodium Hydroxide (NaOH), also known as Lye, in place of the Potassium Hydroxide. You’ll want to titrate using the same catalyst that you’ll be using when you make your biodiesel.  KOH and NaOH can be used interchangeably for a number of applications, although in industry, NaOH is preferred because of its lower cost.Titration is nothing more than determining how much of a base it’s going to take to neutralize the free fatty acids in a sample of the oil to be used to make biodiesel.  A PH indicator called Phenol Red or Phenolphthalein. Both of these ‘indicators’ are typically available at laboratory stores, pool stores, or online.  Phenolphthalein is a chemical compound with the formula C20H14O4 and is often written as “HIn” or “phph” in shorthand notation. Often used in titrations, it turns colorless in acidic solutions and pink in basic solutions. If the concentration of indicator is particularly strong, it can appear purple. In strongly basic solutions, phenolphthalein’s pink color undergoes a rather slow fading reaction and becomes completely colorless above 13.0 pH.
Materials Needed
1- (3) small cups that can hold at least 50 ml of liquid
2- (3) small syringes that are metered in 1 ml increments up to 10 ml
3- 100ml of 91% Isopropyl Alcohol
4- 5l of distilled water
5- 1 gram of Potassium Hydroxide (KOH) or Sodium Hydroxide (NaOH)
6- Either Phenol Red or Phenolphthalein (both will work)
7- A seal-able container that can hold at least 1 liter of liquid
8- A scale that can measure down to .05 of a gramtitrationkitdeluxe-300x300Description:  The ultimate titration kit.  In addition to the items in the Basic Titration Kit, you can added a nice 50 ml Glass Flask, a 250 ml Glass Flask and a Porta Stirrer or make your own Magnetic Stirrer.  By using the glass flasks, you’ll get an extra clear picture of what’s going on.
TITRATION INSTRUCTIONS

Create A Stock Testing Solution
This will create a testing solution that can be used for each titration.
1- Add 1 Liter of Distilled Water to the 1 Liter container
2- Add 1 gram of KOH or NaOH to the 1 liter container
3- Shake the solution around until all of the KOH dissolves
4- Label the container TITRATION SOLUTION
NOTE: About every 90 days, remake this solution as it does “expire”.Label The Bowls
Cup 1- Titration Solution
Cup 2- Alcohol
Cup 3- Titration

Prepare The Bowls
1- Pour about 30 mL of Titration Solution into Cup #1
2- Pour about 20 mL of Isopropyl Alcohol into Cup #2

Prepare Titration Bowl
1- Add
1 mL of oil to Cup #3
2- Add 10 mL of Isopropyl Alcohol from Cup #2 to Cup #3
3- Mix the oil & alcohol together until it’s a consistent solution
(sometimes heating the bowl will help it mix together. Warning do not exceed 60°C)
4- Add 4 drops of Phenol Red or Phenolphthalein to Bowl #3

The Actual Titration Process
1- Suck up 10 mL of testing solution into a syringe from Cup #1
2- Drop a drop of testing solution into Cup #3, watching for a color change each time
3- Hold the bowl in your hand and swirl the solution around for 30 seconds
4- If the color change goes way, add another drop of solution from the syringe
5- Repeat steps 2-4 until the color change stay’s for at least 30 seconds
6- Record on a piece of paper how many ml of solution you put in Cup #3 to keep the color change.

The Titration Calculation (see Biodiesel Formula & Cost Calculator)
If you’re using KOH (Potassium Hydroxide) in the titration solution
-Add 7 to the result from step 1
If you’re using NaOH (Sodium Hydroxide) in the titration solution
-Add 5.5 to the result from step 1
The result will be how many grams of catalyst you’ll use per liter of oil

Example:
100 liters of oil to be converted to biodiesel
It titrated to 4
If KOH, add 7 + 4 = 11 grams/liter X 100 liters = 1100 Grams
If NaOH, add 5.5 + 4 = 9.5 grams/liter X 100 liters = 950 grams
Add 1100 grams of KOH or 950 grams of NaOH to the methanol to make biodiesel using this oil.

Accounting For Catalyst Purity
In most cases it will be difficult to find 100% pure KOH or NaOH. Here’s how to account for that. Simply divide the “BASE” by the purity.
If KOH is used and it’s 90% pure, then divide 7 by .90 (7/.90 = 7.8)
If NaOH is used and it’s 95% pure, then divide 5.5 by .95 (5.5/.95 = 5.8)
Now, instead of using 7 or 5.5, use the “corrected” numbers to calculate how much catalyst is needed.

ADDITIONAL COMMENTS
It’s recommended to do a titration 3 times and record the three results. If the results are close (+/- 1), then you’re set. If it’s way off, you’ll want to repeat the titration ensuring that you follow the steps exactly until your results are close.

Also, only use each syringe for one purpose. For example, use one syringe for oil only, use a separate syringe for the titration solution, and another separate syringe for the alcohol. If you mix them it can cause inaccurate titration.


Helpful Conversion Factors
1 Gallon = 3.785 Liters
1 Pound = 453.59 Grams

Free Fatty Acid Conversion Factor
For KOH Titration Solution: Titration Value / 1.8 = Approximate FFA%
For NaOH Titration Slution: Titration Value / 1.3 = Approximate FFA%