30.4 Technical Questions

1.  Discuss about raw material of soap ?

Ans:

• •  Fatty constituents from refined tallow, coconut and palm oil, refined grease, byproducts of vegetable oil refining etc.

•  In India, for the source of fatty acids mostly depends on imported tallow and palm oil.

•  Coconut oil is the primary vegetable oil used for the manufacture of soaps.

 

2.  Discuss economy in soap manufacturing process ?

Ans:

• •  The vacuum still uses the steam from triple effect evaporator thus reducing the make up steam in the still.

•  Good amount of glycerin is produced as a byproduct which is sold in market.

•  Fatty acid is also taken out as a marketable product. These fatty acids find use in manufacturing cosmetics, beauty products etc.

 

3.  Why is ion exchanger used ?

Ans: 15 – 20% glycerin (sweet water) along with impurities from the hydrolyser is put to the successive beds of anion and cation exchange resin. The glycerin reacts with salts. Ion exchange removs the colour and dissolved salts.

4.  What is the difference between soft soaps and hard soaps ?

Ans:

• •  Sodium salts are called hard soap where as potassium salts are soft soaps.

•  A hard soap is moderately soluble in water and doesnot lather easily whereas soft soap dissolve faster and lather readily.

•  Soft soap performs better than hard soaps in cleansing action.

•  Tallow, animal fats and coconut oils are the main sources of hard soaps, while linseed oil, castor oil etc produces soft soaps. Mahua and ground nut oil produce intermediate consistency soaps.

 

References:

1. Dryden C. E., Outlines of Chemical Technology, East-West Press, 2008

2. Shreve R. N. ,   Austin G. T., Shreve's Chemical process industries, McGraw – Hill, 1984