Glycerol is a sugar alcohol used in soaps and moisturizing lotions because of its high hygroscopic content (it easily absorbs water from the air). Glycerol can also be used to preserve fruit and scientific specimens in biological research. Glycerol is also useful in the lubrication of molds, baking, candy and printing inks, as well as preventing hydraulic jacks from freezing. Although it can be made from vegetable oil, the most common method of making glycerol is from animal fats. Check out step 1 below to make your own glycerol.
Step
Step 1. Prepare animal fat to be used
While any type of animal fat can be used, beef fat is the most commonly used. Remove all the skin, muscles, ligaments, tendons, and flesh to get the fat only or commonly called tallow.
Step 2. Melt the fat
Cut the fat into small pieces and melt over low heat. Stir as needed.
Step 3. Prepare an alkaline solution
Slowly pour the lye into the water. Be careful handling the container as adding lye to the water will generate heat. Stir the solution slowly.
Step 4. Cool the fat
Once thawed, remove the pan of fat from the heat and stir.
Step 5. Make sure that the ingredients are ready to be mixed
To make proper mixing, the fat and lye must have a temperature of about 35 degrees Celsius.
Step 6. Mix fat and lye solution
Slowly pour the lye into the fat and stir constantly.
Step 7. Add salt
Pour the salt into the mixture and keep stirring. Add salt until a thick syrupy froth forms on the surface (with the liquid underneath). If froth is present, stop stirring.
Step 8. Remove the syrup
Once the mixture has cooled and has formed a texture that can be removed from the pan with a strainer spoon, remove the syrup layer. The remaining liquid in the pan is glycerol.
Determine what the syrup that has been removed will be made into. The syrup is actually soap. The syrup can be melted again and poured into molds to make bar soap. Or, you can also dispose of them in a safe way
Step 9. Strain the glycerol
Once the glycerol has cooled, pour the glycerol through a small sieve to filter out any impurities. This process will not remove all the dissolved salt. To remove it, the glycerol must be distilled. The result of the distillation is the final amount of glycerol.
Tips
Heating the fat will produce an unpleasant aroma. Heat the fat in a place with a smooth airflow
Warning
- Alkalis are caustic (capable of burning the skin), especially on soft membranes such as the mouth and tongue. Handle lye with care.
- A mixture of lye and water will produce heat that exceeds 93 degrees Celsius. Only use special containers made of tempered glass to store lye solutions.
