Today, hydrogen peroxide is manufactured almost exclusively by the Riedl-Pfleiderer or anthraquinone process (developed by BASF, the largest chemical company in the world) which was formalized in 1936 and patented in 1939, and involves the autoxidation of a 2-alkyl anthrahydroquinone (or 2-alkyl-9,10-dihydroxyanthracene) to the corresponding 2-alkyl anthraquinone. Major producers commonly use either the 2-ethyl or the 2-amyl derivative.
Common additives and impurities found in H2O2:
Additives
Purpose
Tin (Stannate) Stabilizes product against decomposition caused by heavy metals.
Phosphate Stabilizes product against decomposition caused by chlorine or heavy metals.
Nitrate Acts as an inhibitor against the corrosion of aluminum.
Impurities
Source
Carbon Organic contamination from the “working solution” or anthraquinone.
Aluminum From contact with metallic process equipment and piping.
Chloride From plant water supply.
Sulfate From plant water supply.
Ammonium From plant water supply or degradation of organic amines.
35% USP food grade H2O2 is readily available.
It is also present in rain water at an effective level.