Acid, Base & Salt

Sodium Hydroxide

Sodium hydroxide is also known as caustic soda or Iye. Sodium hydroxide comes in the form of pellets, flakes, granules, and solution in market. Sodium hydroxide is a strong base and caustic in nature.

Production of sodium hydroxide from sodium chloride

CHLOR-ALKALI PROCESS:

Sodium hydroxide is obtained by the Chlor-Alkali Process. In this Chlor stands for chlorine and alkali stands for sodium hydroxide, that’s why this is called chlor-alkali process.

In chlor-alkali process electric current is passed through the brine (aqueous solution of sodium chloride). After passing the electric current through brine, sodium hydroxide solution is formed near cathode. In this process chlorine gas is deposited at anode and hydrogen gas is deposited at cathode.

Chlor-alkali process – fig¹

Ref: https://en.wikipedia.org/wiki/File:Membrane_cell.jpg#filelinks

Uses of products obtained in CHLOR-ALKALI PROCESS:

Sodium hydroxide:

In making of soaps

In making of detergents

In making of paper

In making of artificial fibres

In de-greasing of metals, etc.

Chlorine:

In water treatement

Mixed with swimining pool water

In making of PVC

In making of disinfectants

In making of CFCs

In making of pesticides

Hydrogen:

In making of fuels

Margarine

In making of ammonia for fertilizers

Chlorine + Hydrogen:

Chlorine and hydrogen together is used in making of hydrochloric acid. Hydrochloric acid is also known as Muriatic Acid and spirits of salt.

Hydrochloric acid is used in cleaning of steel, making of ammonium chloride, in making of medicines and cosmetics, etc.

Chlorine + Sodium hydroxide:

Chlorine and sodium hydroxide together is used in making of bleach for household bleaches and bleaching of fabrics, etc.