Commercially is now prepared by –
(A) Action of on barium peroxide
(B) Action of on sodium peroxide
(C) Electrolysis of
(D) By burning hydrogen in excess of oxygen
(C). Commercially is prepared by electrolysis of sulphuric acid.
Hydrogen peroxide is prepared by the electrolysis of 30% to 50% ice-cold H2SO4. When acidified sulfate solution is electrolyzed at high current density, peroxodisulphate is obtained. Peroxodisulphate is then hydrolyzed to get hydrogen peroxide.
2HSO–4(aq) [Electrolysis] → HO3SOOSO3H(aq) [Hydrolysis] → 2HSO–4(aq)+2H+(aq)+H2O2(aq)