Anthraquinone as a catalyst in the production of hydrogen peroxide

Hydrogen peroxide, which is produced worldwide in quantities of 800,000 tpa is manufactured by wet-chemical processes based on barium peroxide, electrochemical processes and organic autoxidation processes. Hydrogen peroxide production by autoxidation was developed to industrial viability by BASF in the 1930 s, in the form of the hydrazobenzene process. The hydrazobenzene process, however, was characterized by the disadvantage that sodium amalgam had to be used to reduce azobenzene to hydrazobenzene. Georg Pfleiderer and Hans-Joachim Riedl then used alkylated anthraquinones in place of azobenzene. The first plant to use this process to produce H2O2 was started in Memphis, Tenn. by Du Pont in 1953. 

In the anthraquinone process, an alkylanthraquinone is catalytically reduced to the corresponding hydroquinone with hydrogen the hydroquinone reacts with oxygen (air), becoming re-oxidized to the anthraquinone derivative, with the formation of hydrogen peroxide. 

Reaction conditions in hydroquinone production are selected to ensure the most selective hydrogenation possible of the oxygen of quinone to the hydroquinone. 

1 Hydrogenation reactors 2 Gas separator 3 Storage vessel 4 Backwash pump 5 Backwash circuit 

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