Making bar soap from glycerol
A quick guide to making bar soap (based on a recipe from Chug)
Contents
Ingredients
1 litre of demethed glycerol
Approx 80 ml of water
Approx 35 g of NaOH
You may have to play with these figures slightly to suit your glycerol,so test batches are recommended!
Method
Heat the water to 50 C and add the NaOH,stir until dissolved (do not breathe the fumes) Add this mix to the glyc and continue heating while stirring the mix will foam and froth then will start to thicken (now is the time to add any scents) Allow the mix to cool slightly Pour the mix into your chosen mould and leave for 7 days to harden enough to be cut into squares The soap will continue to harden over the next few weeks You can add essential oils such as lavender to the mix to give a nice fragrance and you can also add chopped herbs to impart a scent I have also found that adding silver sand to the mix makes a great exfoliating soap but you have to time the adding of the sand to perfection or it will sink to the bottom
Moulds
For moulds you can use anything that will take a small amount of heat such as margarine tubs and recycling box lids and if you dont get caught muffin trays with the individual compartments are ideal!
Colouring and PH values
This soap will be an uninspiring muddy brown colour but i have found you can use small amounts of food colouring to alter it slightly but dont overdo it or you will end up with a soap that stains your hands
Chug also uses the soaps from his settling tank to give a lighter coloured soap than that made from glyc.
The finished soap should have a PH of between 9.5 – 10.5,you can test the soap with PH indicator strips at my last testing my soap was PH 10 which was ideal The finished soap may sweat as it is hydroscopic just wipe the moisture away
Liquid soap
To make a liquid soap use KOH instead of NaOH but you must use the same catalyst that you used to make the glycerol This is a recipe for liquid soap made with KOH,but i hav,nt tried it out 1 litre of glycerin 500 - 800 ml water 40 g KOH Add any essential oils before adding the water/KOH to the glyc
Warning
Do not use an aluminium saucepan for making soap as the NaOH will react with it and if you intend demething your glycerol make sure you are aware of the dangers of methanol
See also
http://en.wikipedia.org/wiki/Soap#Purification_and_finishing
External links
http://www.pioneerthinking.com/glycerin.html
KH 22:22, 5 December 2010 (UTC)
