Saponification Triglyceride Lye Soap Glycerin

Triglycerides OilsFats (At ambient temperature) Liquid Solid

Any oils can be used to make soap… Linseed Oil Palm oil Coconut oil Fish oil

Oil/FatHardnessBubbling Additive ? Odor Odor Palm oil Coconut oil Linseed oil Sunflower oil Soya oil Walnut oil Tallow (beef) Characteristics of soap made from some oil :

Marseille soap = 72 % oil, with no colouring or artificial additives Marseille Soap is traditionally green or white : (Coprah oil ~ Coconut oil) Green Soap: At least 50% Olive Oil, 22% Coprah oil White Soap: At least 50% Palm Oil, 22% Coprah oil

Where does Potassium come from ? … ashes % (K 2 CO 3 ) Wood Corn residues Bean Banana peel Banana tree Orange peel Potatoe peel Lemon peel Wood ashes contain up to 10 % of K 2 CO 3

Where does Sodium come from ? The Glasswort grow on beaches, it’s a salt tolerant plant witch contain up to 40% of Na 2 CO 3 Glasswort ‘s foliage turns red in autumn

The lye making process First, place a layer of straw at the bottom of a bottomless barrel Then place ashes in the bottomless barrel Next, pour water above and wait for lye solution (2Na + +CO 3 2- )(2K + +CO 3 2- ) The lye solution obtained is : or

Production of NaOH and KOH by electrolysis… …of aqueous solution of NaCl or KCl Sea water : 0.6 mol.L -1 NaCl

Using K OH Using Na OH Soft soap Hard soap

Human’s fat Lye Tyler’s Soap

Oil/Fat mg KOH/ 1g Fat mg NaOH/ 1g Fat Palm oil Coconut oil Linseed oil Sunflower oil Soya oil Lard (pork) Tallow (beef) How many lye ? How many lye ? Saponification value: Lye needed (mg) to saponify 1 g of fat

First step: mix fat and lye At 120°F during 20 minutes 120°F = 50°C

Second step: salting out Mixture of Soap and Glycerin A salt (NaCl) was added Soap Glycerin, (Na + + Cl - ) Soap is less soluble in salt water than in fresh water

Glycerin or not ? Soap are more transparents Like Tyler’s or Marseille’s soap YesNo