OVERVIEW

OVERVIEW

Hydrogen peroxide with formula H2O2 is the cleanest oxidizing agent on decomposition gives oxygen and hydrogen.It is oxidizing and reducing agent but its reducing power is low so mainly used as oxidizing and Bleaching agent in industries bleaching action is due to oxidizing properties. Hydrogen peroxide is the simplest member of the peroxides.It is very unstable when used in high concentrations and deteriorates over time so some external agent has to be used to stabilize hydrogen peroxide which is mainly an organic compound. Contact to hydrogen peroxide severely effect mucus membrane, skin, eyes and other parts of the body.

Properties of Hydrogen Peroxide:
The physical and chemical properties of hydrogen peroxide are as follows:
  • It is a colourless liquid
  • It is slightly more viscous than water
  • It is a strong oxidiser
Production of Hydrogen Peroxide:
Electrolysis of Ammonium bisulphate and sulphuric acid: Here in this process a large amount of electrolysis of ammonium bisulphate in sulphuric acid is done to produce sulphuric acid solution of ammonium persulphate which is then treated under distillation with subsequent cooling which then reaction with water forms hydrogen peroxide. In this process the residual is again send to for electrolysis and cycle is repeated. The overall reaction for the process is given below.
(NH4)2S2O8 + 2H2O → H2O2 + 2(NH4)HSO4

Autoxidation Process: These days, it is manufactured by the anthraquinone process also known as AO i.e. Autoxidation process. Hydrogen peroxide is produces using hydrogen and oxygen from air and the reaction is done over anthraquinone which acts as a reaction carrier here. Steps of the reaction are as follows-
  1. Anthraquinone with steam containing Hydrogen based carrier solvent (work solution) is fed into the hydrogenator reactor where hydrogenation reaction occurs over Ni and Pd catalyst gives Anthraquinol.
  2. Before sending the product from 1st reactor to 2nd reactor referred as oxidizer are filtered and cooled. The oxygen enriched air or oxygen with Anthraquinol is fed to second reactor where oxidation reaction occurs gives anthraquinone and hydrogen peroxide.
  3. Hydrogen peroxide is separated from work solution containing 40% hydrogen peroxide after cooling using liquid-liquid extraction where water is used as a medium.
  4. Hydrogen peroxide is sent vacuum column and Anthraquinone is then sent to purifier it is reactivated before send to recycling unit.
  5. Product from vacuum is preheated using steam and sends to the extractor to remove water-hydrogen peroxide mixture there may be multiple extractors depending upon the desired purity required. Distillation is used to get purity up to 70%. Inhibitors are added to hydrogen peroxide to avoid its reaction with metals.
The final reaction is as follows-
H2 + O2 → H2O2