Hydrogen Peroxide Synthesis: An Outlook beyond the Anthraquinone Process

• Published in: Angewandte Chemie International Edition Vol. 45; no. 42; pp. 6962 - 6984
• Main Authors: Campos-Martin, Jose M., Blanco-Brieva, Gema, Fierro, Jose L. G.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 27-10-2006; WILEY‐VCH Verlag
• Subjects: direct synthesis; green chemistry; hydrogen peroxide; liquid-phase reactions; oxidation
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.200503779

Hydrogen peroxide (H2O2) is widely used in almost all industrial areas, particularly in the chemical industry and environmental protection. The only degradation product of its use is water, and thus it has played a large role in environmentally friendly methods in the chemical industry. Hydrogen peroxide is produced on an industrial scale by the anthraquinone oxidation (AO) process. However, this process can hardly be considered a green method. It involves the sequential hydrogenation and oxidation of an alkylanthraquinone precursor dissolved in a mixture of organic solvents followed by liquid–liquid extraction to recover H2O2. The AO process is a multistep method that requires significant energy input and generates waste, which has a negative effect on its sustainability and production costs. The transport, storage, and handling of bulk H2O2 involve hazards and escalating expenses. Thus, novel, cleaner methods for the production of H2O2 are being explored. The direct synthesis of H2O2 from O2 and H2 using a variety of catalysts, and the factors influencing the formation and decomposition of H2O2 are examined in detail in this Review.
The industrial synthesis of hydrogen peroxide by the anthraquinone process requires multiple unit operations and bears several disadvantages, such as the generation of by‐products and significant energy requirements. Thus, the direct synthesis of hydrogen peroxide from H2 and O2 (for example, with the aid of a Pd catalyst, see scheme) is a chemically and technologically significant alternative.