How to Make Lye Soap from Biodiesel By products

Step-by-Step Guide

1. 1

   Step 1: Place the glycerin in a stainless steel pot and heat it to 150 °F (66 °C) to remove any traces of methanol.

   Heat it to 175 °F (79 °C) if you made your biodiesel from ethanol.
2. 2

   Step 2: Strain the glycerin to remove any impurities and then return it to the pot.

   , of water for every gallon of glycerin and heat the water to 100 °F (38 °C).
   
   This works out to a 1-to-4 ratio of water to glycerin. , of lye (38.5 grams per liter) into the heated water until it is completely dissolved. ,,, You may see it start to foam. , A plastic storage bin with a lid works well.
   
   The size and number of containers needed depends on the amount of glycerin you are using and the desired thickness of the soap.
   
   For 1 ½ gallons of glycerin, use a 28-qt. container to make 1 ½-inch-thick soap. , Let it cool and solidify for 24 hours. ,,, During this additional drying time, the soap will turn from a dark brown to a lighter tan color. ,
3. 3

   Step 3: Measure 1 qt.

4. 4

   Step 4: Stir approximately 5.5 oz.

5. 5

   Step 5: Add the water and lye mixture to the glycerin.

6. 6

   Step 6: Continue to heat for another 10 minutes

7. 7

   Step 7: stirring occasionally.

8. 8

   Step 8: Remove the mixture from the heat and stir for another 10 minutes.

9. 9

   Step 9: Pour the mixture into a shallow container.

10. 10

    Step 10: Cover the liquid with a piece of plywood or cardboard to help hold the heat in so the soap cures properly.

11. 11

    Step 11: Run a knife around the edge of the soap to loosen it and then flip the container over to remove the soap.

12. 12

    Step 12: Cut the soap into 45 bars that measure 3-by-2 inches (5.1 cm).

13. 13

    Step 13: Wait at least 4 more days before using the soap.

14. 14

    Step 14: Store the soap in zipper plastic bags with wax paper between the bars so they don’t stick together.

Detailed Guide

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