Chlor-Alkali Electrolysis

2NaCl + 2H2O → Cl2 + 2NaOH + H2

Aperçu

Electrolysis of concentrated brine (NaCl solution) produces three essential industrial chemicals simultaneously: chlorine gas at the anode, sodium hydroxide solution at the cathode, and hydrogen gas as a byproduct. Modern membrane cells use ion-exchange membranes to separate products and achieve 95%+ current efficiency.

Participants

Rôle Substance Coefficient État
Réactif Sodium Chloride NaCl 2 (aq)
Réactif Water H₂O 2 (l)
Produit Sodium Hydroxide NaOH 2 (aq)

Exemple du quotidien

The chlorine in your tap water and the lye in drain cleaner both come from this single electrochemical process.

Importance industrielle

The chlor-alkali industry produces about 75 million tonnes of NaOH and 65 million tonnes of Cl₂ annually, consuming about 1% of global electricity.

Propriétés

Type
Electrochemical
Réversible
Non
Énergie
Endothermique
ΔH
422,0 kJ/mol

Réactions associées

Electrolysis of Water Electrolytic Production of Chlorate Electrorefining of Copper Alkaline Battery Discharge Anodizing of Aluminum Cathodic Protection (Zinc Sacrificial Anode) Chrome Electroplating Nickel-Metal Hydride Battery Sodium-Sulfur Battery Electrochemical CO₂ Reduction to CO

Frequently Asked Questions

What is the equation for Chlor-Alkali Electrolysis?
The balanced equation is: 2NaCl + 2H₂O → Cl₂ + 2NaOH + H₂.
What type of reaction is Chlor-Alkali Electrolysis?
Chlor-Alkali Electrolysis is a electrochemical reaction.
Is Chlor-Alkali Electrolysis exothermic or endothermic?
Chlor-Alkali Electrolysis is endothermic (absorbs energy). The enthalpy change (ΔH) is 422.0 kJ/mol.