Project Topics

Engineering Projects


Preparation of Toilet Soaps.


Soaps are water soluble sodium or potassium salt of higher fatty acids.Soaps are made from fats,arid oils,their acide by treating them chemically with a strong alkali.The fats and oils used in soap ,aking come from animal or plant sources.Each fat or oil is made up of a distinctive mixture of several different triglyceride molecule,three fatty acid molecules are attached to one molecule of glycerin.

There are many types of triglycerides,each type consists of its own particular combination of fatty acids.Fatty acids are the components of fats and oils that are used in making soap .they are weak acids and are composed of two parts.aA carboxylic acid group consisting of one hydrogen(H)atom,two oxygen atoms and one carbon atom,plus a hydrocarbon chain attached to the carboxylic acid group.The alkali used in soap making was obtained from ashes of plants,but they are now made commercially.

Today the term alkali describes a substance that chemically is a base and that reacts with and neutralizes an acid.The common alkalis used in soap making are sodium hydroxide,also called caustic soda and potassium hydroxide,also called caustic potash.when soap is shaken,it produces foam which is responsible for removal of dirt.a soap which produces more foam is more effective in cleaning.So a best soap among a group of much soap can be identified by comparing their foaming capacities.more the time taken for the disappearance of foam more is its foaming capacity and more efficient it is,in its cleansing action.

Cleansing Action of Soap

Soap is sodium or potassium salt of higher fatty acid and may be represented as RCOO¯Na+.when dissolved in water,it dissociates into as RCOO¯ and Na+ ions.The RCOO¯ ions however consist of two parts a long hydrocarbon chainR (also called non polar tail)which is hydrophobic (water loving).The RCOO¯ions are therefore,present on the surface with their COO¯ group in water and the hydrocarbon chains are staying away from it and remains at the surface.But at critical micelle concentration,the anions are pulled into the bulk of the solution and aggregate to form a spherical shape with their hydrocarbon chains pointing towards the center of the spheres with COO¯ part remaining outward on the surphase of the sphere.An aggregate thus formed is known as ‘ionic micelle’

Soap is an excellent cleanser because of its ability to act as emulsifying agent.An emulsifier is capable of dispersing one liquid into another immiscible liquid.This means that while oil does not naturally mix with water,soap can suspend oil/dirt in such a way that it can be removed.The cleansing action of soap is due to the fact that soap molecules form micelle around the oil droplet in such a way that hydrophobic parts of RCOO¯ions is in the oil droplet and hydrophilic part projects out of grease droplet like the bristles.since the polar groups can interact with water.the oil droplet surrounded by RCOO¯ ions is now pulled in water and removed from the dirty surface.thus soaps helps in emulsification and washing away of oils and fats.The negatively charged sheath around the globules prevent them from coming together and forming aggregates


• COCONUT OIL – 1200mL
• Water -600Ml
• COLOUR -200g


1. First of all , NaOH is added to 600mL of water and kept aside for 5 hours.

2. To another container containing 200 mL oil,colour is added and stireed well.

3. To this oil- colour mixture, then added soap stone powder and stirred well till no precipitate or solid component exists.

4. Then add 1L of oil and mixed well.

5. Now add the dilute NaOH solution prepared at the initial step to the oil-colour mixture

6. Then the solution is stirred in the clockwise direction for 35-45 minutes in a medium speed.

7. To this perfume is added and stirred well for 1 minute.

8. It is then transferred into the mould.

9. Next day,the mould is removed and the soap is covered with wrapper.


Toilet soaps of 30 numbers oval in shape 150g each is prepared

• By preparing the soaps,it is possible to find the contents of it
• The soap thus obtained will contain less impurities as it is made under our presence
• In short,this project is the humble contribution in the quest for knowledge exploration


1. World bibliography of sapnification,volume1,volume2,kofan
2. The blue book,holzner,evangles;New Delhi