How to Make Charcoal Soap

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Things You'll Need

  • Tools used only for making soap:

  • Well-ventilated room

  • Safety goggles

  • Long-sleeve shirt

  • Pants, not shorts

  • Shoes that cover the feet

  • Thick industrial rubber gloves

  • Kitchen scale with "tare" function

  • Instant digital-read food thermometer

  • Two heatproof 4-cup/32-oz. glass measuring cups

  • Plastic, ceramic or glass bowl

  • 3 stainless steel 2-quart bowls

  • Plastic or silicone spoon

  • Stick blender or metal whisk

  • Small cardboard box or small used plastic food containers

  • Plastic cellophane food wrap

  • Freezer paper

  • Butcher paper

  • Large kitchen knife

  • Assorted measuring spoons

  • 4-quart slow cooker with glass insert

  • Metal mesh bakery cooling racks

  • Warm water

  • Paper towels

  • Dish soap

  • White food-grade vinegar

  • Cold-lye method--2-Pound Yield:

  • (Measure by weight, not volume)

  • 6 oz. distilled water

  • 2.25 oz lye (sodium hydroxide)

  • 10 oz. olive oil

  • 6 oz. coconut oil

  • 1 tbsp (0.45 oz.) castor oil

  • Slow Cooker --Hot Process-- 3-Pound Yield:

  • (Measure by weight, not volume)

  • 11 oz. distilled water

  • 4.9 oz. lye (sodium hydroxide)

  • 18 oz. olive oil

  • 8 oz. coconut oil

  • 6 oz. palm oil shortening

  • 2 oz. shea butter

  • 1 oz. castor oil

  • Other Optional Ingredients

  • 2 to 4 ounces food grade activated charcoal (bamboo is best)

  • 1 tablespoon essential oil of choice

  • 5 to 6 tablespoons exfoliant (see tips and warnings)

Image Credit: bars of soap image by Jale Evsen Duran from <a href=''></a>

Charcoal soap is used in Asia to clear skin and smooth complexions. It is a mild exfoliant for delicate skin, absorbs excess oils from the skin and washes away clean. There are two basic methods of making soap at home, and they do not contain harsh chemicals or preservatives.


Properly made and cured lye soap does not actually contain lye when it is finished. The lye and fats trigger a chemical reaction that changes them into glycerin.

Cold-process lye soap does not require any cooking, and the process is quick and simple. However, it takes four to six weeks for the soap to cure before it is safe to use. It also takes more essential oils to scent the soap, as some of the oils are used up while curing.

Hot-process lye soap speeds up the chemical reaction with the lye. The soap is ready to use within a few hours, and less essential oils are needed because they are added after the lye is neutralized. Hot-process soap generally is softer and spongy. It also might have a marbled look ,and the ingredients will not settle to the bottom as they do the cold process.


Getting Set Up

Step 1

Wear long-sleeve shirt, pants and closed-in shoes to protect skin from accidental lye burns.

Step 2

Put on safety goggles and rubber gloves.

Step 3

Line the box with the freezer paper, unless using small plastic food containers for molds.

Cold-Lye Method

Step 1

Weigh the 6 ounces of distilled water, and place in large ceramic or metal bowl. Measure 2.25 ounces of lye, and add to this bowl. Stir gently, and stand back to avoid splashing or inhaling fumes. Never pour water into lye--always pour lye into water. This mixture will get very hot.


Step 2

Weigh the 10 ounces of olive oil, 6 ounces of coconut oil and 0.45 ounces of castor oil, add them to the glass measuring cup, and melt them in the microwave oven, 30 seconds at a time. Avoid over-heating the oils; measure their temperature with the food thermometer. When they are 90 to 110 degrees Fahrenheit, they are ready. Stir them until incorporated well.

Step 3

Measure the temperature of the lye. Add the oils to the lye when they are within 20 degrees Fahrenheit or less of each other. Pour carefully and slowly, stirring while pouring. It's best to work at the higher end of the temperatures, make sure both the oils and the lye water are within 90 to 110 degrees.


Step 4

Stir the mixture, using the stick blender or whisk. When it reaches pudding or gravy consistency--when a few drops of the mixture do not disappear into the mix when dripped back in--it has "traced."

Another way to check for this is when the temperature has risen a couple of degrees from when the mixing started. That is the time to add any ingredients; stir the soap thoroughly to incorporate them.

Step 5

Pour the mixture into the lined container or plastic molds, and cover with plastic wrap. Allow this to set for 48 hours. Then, while wearing the goggles and gloves, check the soap. If it has set, it will be solid, with a smooth surface. If it is not solid and smooth--that is, it looks like water has separated from the soap or the soap is crumbly or shiny--something went wrong, and the batch should be tossed out. Start over with a new batch.


Keep the gloves and goggles on while working since the lye is not fully neutralized. Do not wait more than 48 hours to remove the soap from the molds. Remove the soap from the molds carefully, avoiding dropping or breaking it. Gently cut the soap, if a large mold was used, into bar size slices. Arrange these on the bakery cooling racks, and put into a cool, dry place to cure for three to four weeks. Turn the soap daily to ensure even drying.

Hot-Lye Method -- Yields 3 Pounds

Step 1

Weigh the 10 ounces of olive oil and 1 ounce of castor oil, and pour them into the slow cooker. Weigh the 8 ounces of coconut oil, 6 ounces of palm oil and 2 ounces of shea butter in the other 32-oz glass measuring cup. Melt the solid fats in the microwave 30 seconds at a time, until 90 to 110 degrees Fahrenheit.


Weight the 11 ounces of distilled water in the other 32-ounce glass measuring cup. Weigh the 4.9 ounces of lye, and slowly add it to the water. Stand back to avoid being splashed or breathing in the fumes.

Step 2

Pour the melted solid fats in the slow cooker, and stir until well-mixed. Add the lye to the slow cooker until the oils and lye are within 20 degrees Fahrenheit of each other and between 90 and 120 degrees. Pour slowly and stir gently to avoid splashing.

Use the stick blender or the whisk to mix the solution until it a thin gravy or pudding consistency. When the blender or whisk is removed from the mixture and it drips back down, it should leave a pattern on the surface. Check the consistency every 5 to 10 seconds while mixing until this consistency is reached. This is called "trace" and also is measured by temperature if the temperature has risen a few degrees from the original temperature of the oils and lye.


Step 3

Set the slow-cooker temperature to low, and place the lid on it once "trace" is reached. Check the mixture after about 15 minutes to see any separation has occurred. Once it has, stir it with the spatula to mix it back together. Replace the lid.

Check the mixture again in 20 to 30 minutes. The outside edge of the mixture should start turning translucent. Continue checking the soap at regular intervals. When the mixture has turned translucent most of the way, stir it with a spatula. Let it cook for another 20 to 30 minutes. The next time it is checked, it should look like applesauce with oil on top. Simply mix it together again.


Step 4

Turn the slow cooker off after 1.5 hours to 2 hours of cooking time. The soap mixture should begin to resemble petroleum jelly. At this point, extra ingredients such as essential oils, activated carbon and exfoliants can be added. Stir the mixture well to incorporate them fully. The cold-process method uses about half the amount of essential oils as the hot-process method.

Scoop the soap out and put into the molds of your choice. Unlike the cold-lye method, the hot-lye soap will be thick and sticky. Be sure to bang the molds a few times on the counter to help remove air bubbles. Fill the containers to the brim, and pack them from corner to corner, filling in all spaces. Work quickly, as this soap "sets up" quickly, forming a skin on its surface that additional soap will not stick to.

Step 5

Remove the soap from the mold when it is cool to the touch. Place it on the wire mesh baking racks to cool. The cold-process soap can be used immediately, but it is best if left to mature for a couple of weeks before using.

Cleaning Up

Step 1

While still wearing the goggles and gloves, clean the area with paper towels, a little dish soap and warm water.

Step 2

Clean all the tools, and place them in a container. Use these tools again only when making soap.

Step 3

Clean the slow cooker by filling it with water and allowing the soap residue to dissolve.


Place the empty glass container on the scale, and press "tare" to remove its weight from the total. Then add the ingredient being measured in order to get an accurate weight measurement. If the ingredients are inaccurately measured, the soap will not work.

Store soap in a ventilated container in a cool, dark place. Do not allow stored soaps to set in direct light or sunshine. Improperly storing the soap will make it go bad quickly. Homemade soap does not contain preservatives and will go bad within a year in cool areas and six months in hot or humid areas. Use it or give it away before it goes bad.

Reduce heat produced by mixing the lye with water by dividing the water in half and freezing half the water into ice cubes. Mix the ice and room-temperature water before adding the lye. Or, place the bowl of water into a sink filled with cool water before adding the lye.

Different manufactures produce different grades of essential oils. Some essential oils are mixed into a base of other oils rather than pure essential oil by itself. For his reason adding essential oils is subjective. Test essential oils by themselves the day before by mixing a few drops of up to three different chosen essential oils and placing this bowl in a salad container. Experiment with several kinds of combinations until you find one you like.


Never pour water into the lye--the strong reaction could cause splashing and lead to injuries.

If soap mixture or lye water do splash onto the skin, rinse with white vinegar and call an emergency center.

Never use non-stick cookware, aluminum, cast iron, tin, tin cans, tin pans or metal utensils--the lye will react to them, and the soap and the tools will be ruined. Never use wood--it will be broken down by the lye.

Different exfoliants can be used, such as ground almond meal, ground fruit pit hulls, ground dried fruit skins, ground oatmeal, dried baby cereals, ground walnut hulls, courser ground activated carbon, ground loofa bits, mica, flour, baking soda, dried herbs, fine sand, loose dried tea, dried tea as found in tea bags, psyllium hulls, sugar, dried ground fruit, unused coffee grounds, cocoa powder or even carob powder.

Experiment with one or two, and test the combination the day before you make the soap. If using essential oils, test the exfoliant mixture with the essential oil mixture before adding it to the soap.


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