PRODUCTION OF BAR SOAP AND DETERGENT
Today in every market exists different types of soap and detergents. Some of them are not efficacious as advertised because the ingredients of such soaps are not always in right proportion and as such the efficacy of active ingredients is not rendered. Soaps are the sodium salts or potassium salts of stearic acids or any other fatty acids. They are prepared by the saponification process, which is, reacting the oil which contain triglycerides with caustic soda (NaOH) to give the soap. However different oils have different composition of fatty acids which are responsible for different properties of soaps made out of them. In the present work 5 different types of oils are taken. They are blended in various ratios to prepare 14 different samples of soap. Different properties of these samples were analyzed to see which soap is the best one. The cleansing and lathering properties of all samples were compared. The blend of coconut oil and castor oil at 3:1 ratio is found out to be the best with 76.8% of TFM and 89.46% of yield. The best blend is analyzed for various properties and they were compared with that given in the literature. The saponification values, iodine values of coconut oil and castor oil were found out and these values were also found for the blend. It was found that the blend was having SAP value of 230.4 and iodine value of 40 which are higher than the individual values. Thus soap prepared using blend of both these oils has better properties than the soaps prepared by individual oils.
Soap can be defined as the sodium or potassium salt of fatty acid, made by hydrolyzing fats and oils with caustic alkali (cook 1964). Soap acts as a good cleansing agent in soft water, at an interphase of greasy and water. In hard water soap reacts with the mague sum and calcium ions to form insoluble precipitate (scum), which lowers the cleansing effect of the soap. This abnormality in soap led to the introduction of synthetic detergent.
Detergents are sodium salts of an acid. They are substance that causes oil or grease to form emulsions in water so that soap acts as a cleansing agent.
A soap is also a salt of a compound, known as a fatty acid. A soap molecule has a long hydrocarbon chain with a carboxylic acid group on one end, which has ionic bond with metal ion, usually sodium or potassium. The hydrocarbon end is non polar which is highly soluble in non polar substances and the ionic end is soluble in water. The structure of the soap molecule is represented below:
The cleaning action of soaps because of their ability to emulsify or disperse water-insoluble materials and hold them in the suspension of water.