Definition of Saponification and Reaction

Saponification is the process in which the fat, oil or lipid get converted into soap or triglyceride. While reacting with potassium hydroxide or sodium hydroxide; fatty acids formed up as soap. Which is also known as glycerol and fatty acid salt too. Most of the existing triglycerides are either vegetable oil or animal fat. Many of us must have studied that in this process of saponification; if the sodium hydroxide is used then the hard soap will be produced and potassium hydroxide will produce the soft one. In One or two easy steps triglycerides are reacted with a strong base in which the ester bond is tear out and produces glycerol and fatty acid salts (soap). Grave wax is a term often used in this process where adipocere is converted from fat in a corpse.

What is Saponification value?

Saponification value is the total amount of base required to process a fat sample or a lipid sample. Some industries that makes various soaps; introduce their procedure of making soaps with a small deficit of lye for being reasonable for the unknown dislodgement of saponification value between laboratory average and oil batch.

Methods of Saponification

There are several methods available for saponification. Lipids that includes ester linkages can be incurred by hydrolysis. And this particular reaction is performed by a strong base or acid. Alkaline hydrolysis of fatty acid esters is well known as saponification. The mechanism of the saponification includes:

  • nucleophilic attack of the hydroxide ion
  • removal of the leaving group
  • deprotonation

It has been already mentioned that the chemical reaction between fatty acid and and sodium or potassium hydroxide is called as saponification reaction.

equ: fats + sodium or potassium hydroxide ——> glycerol + soap

There is also a lead method of saponification; which is the saponification of fatty acids.

Reaction between Several fatty Acids and base becomes the essential method of saponification. This procedure includes neutralisation of carboxylic acid. Most of the time this process of neutralisation is used to produce various soaps derived from some transition metals, aluminium and magnesium. Soaps that are formed from one particular fatty acid and stands with a predictable physical property are getting produced by this method of saponification which is the quite ideal method, as required by engineering applications.

Two step process of Saponification

You guys must have known the fact from the above explanation that the most frequent and convenient way of saponification is the reaction between any of the triglyceride and lye, Which is the single step easy reaction. But there is a two step process available; in which triglycerides get steam hydrolysed and out-turn glycerol and carboxylic acid. In the next step Fatty acid get neutralised by alkali to produce soap.

Yes, one question might appear here that, why do anyone need to apply the two step process instead of one step process? Well this process of saponification is a slow process but this mode of saponification allows the purification of the fatty acids and can produce high quality soaps.

Key points of Saponification

  • Saponification is the mode of reaction in which various soaps get produced.
  • This process includes the conversion of vegetable oil or animal fat into soap. Solution of alkali and heat is the most important requirement for this reaction
  • This mode of reaction is used to produce fire extinguishers, soaps and lubricants commercially.

uses of Saponification

It is kind of clear that the saponification is very much needed for our daily lives. Several other important works can also be done throughout this process

Lithium Soaps

Lubricating greases includes little lithium quantities of 12-hydroxistearate and other fatty acids. Lithium carboxylates in lithium based greases are often  used as thickeners. Complex soaps does the same job; being the combinations of acetic or azelaic acid.

Fire Extinguishers

Fire is often made up of cooking fats and oils that can be burnt out way hotter than any other flammable liquids; leaving any kind of standard extinguisher ineffective. Some wet chemical extinguishers can be effective to extinguish such fire. And this kind of fire extinguishers can only be produced through the process of saponification.

Effects on oil Paintings

Saponification can take part in oil paintings too. Within a long duration of time saponification can harm old oil paintings. Oil paintings are often made by pigment molecules which are composed by heavy metal salts such as red lead and zinc white. If these metal salts comes in contact with the fatty Acids of the oil medium of the painting and reacts with it then metal soaps can be formed as a dense soap layer on the outer surface of the painting.
The fact that saponification happens in oil paintings was unveiled in 1912 for the very first time. Then some observers felt that this thing is needed to be widespread as saponification was being observed in so many antique paintings from the twentieth centuries. Some different geographical paintings and works were also found from those peices. Long time after it was scientifically tested that proper chemical analysis of old paintings may unveil that saponification can be ensued in the deeper layer of the the painting until it is appeared on the outer surface.

Final Words

So this is all i wanted to elaborate about the chemical process called saponification. This thing actually holding a great industrial value right now. As you guys have already know that the production of needy essentials like soaps and fire extinguishers can be executed by the process of saponification. So i hope what i have written above about saponification will help you.
So if you really like what you have read then please don’t forget to let me know through the comment section below and also if i have missed out something important. Thank you very much for going through my informative.

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