Saponification Process Of Soap

The saponification (a reaction in making soap) process is a base (usually NaOH or KOH) hydrolysis of triglycerides to make salt (soap) and glycerol. Alkalis such as Sodium carbonate and Sodium hydroxide are used to neutralize the fatty acid and convert it to a salt. The molecules crystallize differently depending on the base used. NaOH produces a harder bar while KOH is used more frequently for liquid soaps. In some cases, Lithium soaps are formed and produce much harder soaps. There are four methods of soap production presently in use; the melt and pour method, cold process method, hot process method, and the rebatching method. OR Figure 2.1. The equation for the saponification process of soap production

For centuries,

It can also be defined as a water-soluble cleansing substance which combines with impurities to make them more soluble. It differs from soap by not forming a scum with the salts in hard water.

When a soap or detergent is added to water, the molecules form clusters, known as micelles, in which the polar ends of the molecules are on the outside of the cluster and the non-polar ends are in the middle. The cleansing action of both soaps and detergents results from their ability to emulsify or disperse water-insoluble materials (dirt, oil, and grease) and hold them in suspension in

These ions form precipitates with soap molecules, and this precipitate is often seen as a grey line on a bathtub or sink and is often called soap scum. Since soap forms a precipitate with these ions, it means that many of the soap molecules are no longer present in the solution. Therefore, soap will form fewer bubbles in hard water. Soft water is water that contains very few or no ions that precipitate with soap. Soap will therefore be much more effective in soft water than in hard water.

The steps for the saponification soap making method can therefore be simplified into four:

• Saponification: The fat and oil is mixed with the alkali and heated. The soap produced is the salt of a long chain carboxylic acid.

• Glycerine removal: Saturated salt solution is added to dissolve the glycerine in the wet soap. A greater part of the glycerine is removed and separated from the soap whiles the other part remains to smoothen and soften the soap.

• Soap purification: Any remaining alkali is neutralized by adding a suitable acid and the remaining water is removed.

• Finishing: Additives such as preservatives, colour or perfume are added and then the soap is shaped as