In fact, those chemicals which concentrate at the surface of the solution or interfaces, reduce tension of the solution and help in removing dirt and dust by emulsifying grease are are known as surfactants. Soaps and detergents belong to this class.
`text(Soaps) :` Soaps are water-soluble sodium or potassium salts of higher fatty acids like stearic acid, oleic acid, palmitic acid etc. Soap are obtained by the alkaline hydrolysis of oils and fats. Only glycerides of fatty acid give soaps on alkaline hydrolysis.
`text(Raw Materials) :` The important raw material used for the manufacture of soaps are :
(i) Oil or Fat Mustard oil, mohwa oil, coconut oil, cotton seed oil, olive oil or animal fat.
(ii) Fillers : The substance added to increase the weight and volume of soaps e.g. sodium silicates , powdered pumice , starch , sodium carbonate.
(iii) Alkali Caustic soda for hard or washing soaps and caustic potash for soft soap is used for saponification .
(iv) Colouring Material
ZnO | White colour |
Methylene blue | Blue colour |
Uranium | Yellow |
Eosine | Red |
(v) Perfumes : Perfumes are used to make soap pleasant smelling e.g. lemon grass oil.