Biodiesel DIY


Materials Needed
Feedstock–SVO or WVO
Alcohol–Methanol or Ethanol
Catalyst–Sodium Hydroxide (Lye) or Potassium Hydroxide
Mixing Container–An old blender for mechanical mixing (you won’t be able to use it for food/drinks again) or a thick, clear soda/Gatorade bottle for hand mixing should each work for small batches
Safety Information BrochuresMethanol, Ethanol, Sodium Hydroxide, Potassium Hydroxide

The Process
Step 1: Determine how much you plan to make. The mixture quantities in the following steps will be discussed in terms of percent of volume of feedstock.

Feedstock Catalyst Alcohol
0.35% 0.90%
Methanol Ethanol
20% 30%
See Step 2
Methanol Ethanol
20% 30%

Step 2: Determine how much Catalyst you need. If you are using virgin Feedstock, skip to Step 3. If you are using waste Feedstock, such as used cooking oil, you must go through the titration process.
Step 3: Mix Catalyst and Alcohol. Since roughly 20% of the Feedstock is glycerine, this amount needs to be replaced with Alcohol. Measure 20% of the volume of the Feedstock as Alcohol and mix with the Catalyst, which is 0.35% of the volume of Feedstock. NOTE: This does not always mix easily. If the Catalyst does not mix properly the biodiesel reaction will not work properly. Mixing may take several minutes for small batches.
Step 4: Mix Reactants. Mix the Feedstock with the Catalyst/Alcohol mix. This could take over 15 minutes, depending on mix speed.
Step 5: Allow for Settling. You could see results within minutes, but full results will be best seen after settling for a few hours.

After settling, the container will contain two or three layers. The layer on top is biodiesel; this should be a clear color. The bottom layer is the glycerin, which is dark brown in color. A third layer in the middle represents the amount of materials that went unreacted. For future batches make sure all the Catalyst is dissolved into the Alcohol and ensure there was a long enough mix period.